BIOFUEL CO-PRODUCTS AS LIVESTOCK FEED

Opportunities and challenges

FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONSRome, 2012

BIOFUEL CO-PRODUCTS AS LIVESTOCK FEED

Opportunities and challenges

Editor Harinder P.S. Makkar

Recommended citationFAO. 2012. Biofuel co-products as livestock feed - Opportunities and challenges, edited by Harinder P.S. Makkar. Rome.

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© FAO 2012

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Contents

Preface ixAcknowledgements xAbbreviations used in the text xi

CHAPTER 1An outlook on world biofuel production and its implications for the animal feed

industry 1Geoff Cooper and J. Alan Weber

Introduction: the case for expanding biofuel production – Common biofuels, feedstocks and co-products – Generally accepted uses of feed co-products in animal diets – Historical volumes of feed from biofuel co-products – Biofuels and co-product outlook to 2020 – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 2An outlook on EU biofuel production and its implications for the animal

feed industry 13Warwick Lywood and John Pinkney

Introduction – The need for biofuels to tackle climate change – EU biofuel production – Biofuel processes – Biofuel crops – EU animal feed supply – Biorefining of crops for biofuel and animal feed – Sustainability of biofuels and animal feed – Biofuel and animal feed scenarios for 2020 – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 3Impact of United States biofuels co-products on the feed industry 35

G.C. Shurson, H. Tilstra and B.J. Kerr

Introduction – Evolution of DG production and use in the United States feed industry – Future impact of United States ethanol production on the feed industry – Nutrient composition, digestibility and feeding value of new maize co-products for livestock and poultry – Other emerging or potential processing and maize co-product production technologies – Feed and food safety questions – Expanded uses of co-products – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 4Utilization of wet distillers grains in high-energy beef cattle diets based

on processed grain 61M.L. Galyean, N.A. Cole, M.S. Brown, J.C. MacDonald, C.H. Ponce and J.S. Schutz

Introduction – Concentration and source of distillers grains – Effects of specific nutrients and feed ingredients – Potential interactions with grain processing and feed additives – Environmental effects of feeding wet distillers grains in high-energy, processed grain diets – Knowledge gaps and future research needs – Conclusions – Bibliography

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CHAPTER 5Utilization of feed co-products from wet or dry milling for beef cattle 77

G.E. Erickson, T.J. Klopfenstein and A.K. Watson

Introduction – Beef finishing – Protein supplementation – Energy replacement – High inclusions – Roughages – Grain processing – Sulphur – Forage-fed cattle – Energy supplementation – Protein supplementation – Replacement heifers – Environmental issues – Greenhouse gas and life-cycle analysis – New developments – Future research areas – Conclusions – Bibliography

CHAPTER 6Hydrogen sulphide: synthesis, physiological roles and pathology associated with

feeding cattle maize co-products of the ethanol industry 101Jon P. Schoonmaker and Donald C. Beitz

Introduction – Dietary sources of sulphur – Mechanism of action of excess dietary sulphur– Sources of hydrogen sulphide – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 7Feeding biofuel co-products to dairy cattle 115

Kenneth F. Kalscheur, Alvaro D. Garcia, David J. Schingoethe, Fernando Diaz Royón and Arnold R. Hippen

Introduction – Nutrient composition of biofuel co-products – Degradability of distillers grain from different cereal grains – Feeding DGS to dairy calves – Feeding DGS to dairy heifers – Feeding DGS to dry cows – Feeding DGS to lactating dairy cows – Wet versus dried distillers grain with solubles – Feeding different cereal types of distillers grain with solubles – Feeding other ethanol co-products to dairy cattle  – Feeding glycerol to dairy cattle – Storage of biofuel co-products – Future biofuel co-products (next generation) – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 8Utilization of crude glycerin in beef cattle 155

J.S. Drouillard

Introduction – Fermentation by ruminal microbes – Impact of glycerin on in vivo digestion  – Performance of cattle supplemented crude glycerin – Conclusions – Bibliography

CHAPTER 9Nutritional value and utilization of wheat dried distillers grain with solubles

in pigs and poultry 163J. Noblet, P. Cozannet and F. Skiba

Introduction – Composition and chemical characteristics of wheat DDGS – Energy value of wheat DDGS – Protein value of wheat DDGS – Minerals and phosphorus value of wheat DDGS – Performance in poultry and pigs fed wheat DDGS – Feed additives potential for wheat DDGS – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 10Feeding biofuels co-products to pigs 175

G.C. Shurson, R.T. Zijlstra, B.J. Kerr and H.H. Stein

Introduction – Biofuels co-products used in swine diets – Wet-milling co-products – Nutrient and energy composition and digestibility in distillers grain co-products – Improving nutrient digestibility of DDGS – In vitro energy digestibilty in DDGS – Energy prediction equations for DDGS – Nutrient and energy composition and digestibility in maize co-products from wet-milling – Crude glycerin – Special considerations for co-products from the ethanol industry – Special considerations for crude glycerin – Feeding distillers

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co-products to swine – Feeding crude glycerin to swine – Effects of DDGS on pig health – Effects of DDGS on nutrient concentration and gas and odour emissions of swine manure – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 11Co-products from biofuel production for farm animals – an EU perspective 209

Friederike Hippenstiel, Karl-Heinz Südekum, Ulrich Meyer and Gerhard Flachowsky

Introduction – Co-products from bio-ethanol production – Co-products from biodiesel production – Energy utilization efficiency and sustainability of co-products from biofuel production in animal nutrition – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 12Utilizing co-products of the sweet sorghum-based biofuel industry as livestock

feed in decentralized systems 229P. Srinivasa Rao, Belum V.S. Reddy, Ch. Ravinder Reddy, M. Blümmel, A. Ashok Kumar, P. Parthasarathy Rao and G. Basavaraj

Introduction to the sweet sorghum value chain – Sweet sorghum as bio-ethanol feedstock  – Co-products – Grain utilization – Animal studies with sweet sorghum bagasse – Utilization of foam, vinasse and steam – Economic importance of bagasse for the sweet sorghum value chain in the decentralized system – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 13Utilization of oil palm co-products as feeds for livestock in Malaysia 243

M. Wan Zahari, A.R. Alimon and H.K. Wong

Introduction – Co-products from oil palm plantations (field residues) – Co-products from oil palm milling – Maximizing livestock production in an oil palm environment – Conclusions – Bibiliography

CHAPTER 14Use of palm kernel cakes (Elaeis guineensis and Orbignya phalerata),

co-products of the biofuel industry, in collared peccary (Pecari tajacu) feeds 263Natália Inagaki de Albuquerque, Diva Anélie de Araujo Guimarães, Hilma Lúcia Tavares Dias, Paulo César Teixeira and José Aparecido Moreira

Introduction – Use of babassu (Orbignya phalerata) in the feed of collared peccaries raised in captivity – Palm kernel cake (Elaeis guineensis) use in the feed of collared peccaries raised in captivity – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 15Sustainable and competitive use as livestock feed of some co-products,

by-products and effluents generated in the bio-ethanol industry 275Harold Patino, Bernardo Ospina Patiño, Jorge Luis Gil and Sonia Gallego Castillo

Introduction – Bio-ethanol production trials with the RUSBI approach – Transformation of co-products, by-products and effluents into nutritional supplements for animal feeding – Bio-economic animal feeding trials with the nutritional supplements – Economic viability of the use of nutritional supplements in animal feeding – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 16Scope for utilizing sugar cane bagasse as livestock feed – an Asian perspective 291

S. Anandan and K.T. Sampath

Introduction – Sugar cane production and co-products – Knowledge gaps and future research needs – Conclusions – Bibliography

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CHAPTER 17Camelina sativa in poultry diets: opportunities and challenges 303

Gita Cherian

Introduction – Camelina sativa meal: chemical composition and nutritional value – Feeding camelina meal to poultry – Developing Camelina sativa as a functional feed: challenges – Conclusions – Acknowledgments – Bibliography

CHAPTER 18Utilization of lipid co-products of the biofuel industry in livestock feed 311

Z. Wiesman, O. Segman and L. Yarmolinsky

Introduction to biofuels – Soapstock – Composition – Phytonutrients – Effect on ruminants – Potential risks from fractions containing such phytochemicals – Conclusions – Bibliography

CHAPTER 19Potential and constraints in utilizing co-products of the non-edible oils-based

biodiesel industry – an overview 325Souheila Abbeddou and Harinder P.S. Makkar

Introduction  – Promising non-edible oil plant species  – Chemical composition of co-products of the non-edible oil-based biodiesel industry – Toxicity of non-edible cakes and meals – Possibility of feeding some untreated non-edible cakes and meals from seeds that give non-edible oils – Possibility of feeding some treated non-edible cakes and meals from seeds that give edible oils – Detoxification methods – Effects of feeding treated non-edible cakes or meals on animal response and performance – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 20Status of biofuels in India and scope of utilizing castor (Ricinus communis) cake –

a biofuel co-product – as livestock feed 339S. Anandan, N.K.S. Gowda and K.T. Sampath

Introduction – Status of biofuels in India – Biofuels feedstock and co-products  – Castor cake production and utilization  – Toxic principles – Detoxification and de-allergenation of castor cake  – Feeding studies using castor cake  – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 21Use of detoxified jatropha kernel meal and protein isolate in diets of

farm animals 351Harinder P.S. Makkar, Vikas Kumar and Klaus Becker

Introduction – Jatropha – Detoxified Jatropha curcas kernel meal as a protein source in aqua feed – Use of detoxified jatropha kernel meal as a protein source in white leg shrimp feed – Use of Jatropha curcas kernel meal of a non-toxic jatropha genotype in aqua feed – Use of Jatropha platyphylla kernel meal as a protein source in aqua feed – Use of detoxified Jatropha curcas protein isolate in common carp feed  – Conclusions regarding use of detoxified kernel meal and detoxified protein isolate from Jatropha curcas as aqua feed – Use of detoxified Jatropha curcas kernel meal in poultry feed – Use of detoxified Jatropha curcas kernel meal in pig feed – Challenges and opportunities in using as livestock feed by-products obtained during the production of biodiesel from jatropha oil – Guidelines for using detoxified kernel meal and detoxified protein isolate from Jatropha curcas as a protein source in animal feed – Potential challenges in using detoxified kernel meal and detoxified protein isolate from Jatropha curcas in feeds – Environmental considerations – Future studies – Final comments – Bibliography

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CHAPTER 22Use of Pongamia glabra (karanj) and Azadirachta indica (neem) seed cakes

for feeding livestock 379Narayan Dutta, A.K. Panda and D.N. Kamra

Introduction – Karanj (Pongamia glabra) cake – Neem seed cake – Recommendations – Knowledge gaps and future research needs – Bibliography

CHAPTER 23Co-products of the United States biofuels industry as alternative feed

ingredients for aquaculture 403Kamal Mjoun and Kurt Rosentrater

Introduction – Properties of distillers grain – Distillers grain: issues, challenges, knowledge gaps and research needs – Properties of crude glycerine – Crude glycerine issues, challenges, knowledge gaps and research needs – Conclusions – Bibliography

CHAPTER 24Cultivation of micro-algae for lipids and hydrocarbons, and utilization of spent

biomass for livestock feed and for bio-active constituents 423G.A. Ravishankar, R. Sarada, S. Vidyashankar, K.S. VenuGopal and A. Kumudha

Introduction – Algal biodiversity for the production of lipids and hydrocarbons – Green algal lipids and hydrocarbons – Diatoms as sources of lipids – Large-scale cultivation of micro-algae – Downstream processing and conversion to biofuels – Conversion of algal lipids and biomass to bio-energy – Ethanol from algal feedstock – Use of micro-algae for food, feed and bio-actives – Micro-algae as sources of feed – Micro-algae as sources of bio-active molecules – Techno-economic analysis of micro-algal biomass production for biofuels, and co-products – Biorefinery approach in micro-algal utilization – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 25Land use in Australia for biofuels and bio-energy: opportunities and challenges

for livestock industries 447Andrew L. Braid

Introduction  – Current biofuel production in Australia  – New production systems for biofuels and bio-energy in Australia – Lignocellulosic-based biofuels – Expanding land use for bio-energy and biofuel: the effect on livestock industries – Knowledge gaps and future research needs – Conclusions – Acknowledgements – Bibliography

CHAPTER 26An assessment of the potential demand for DDGS in Western Canada:

institutional and market considerations 467Colleen Christensen, Stuart Smyth, Albert Boaitey and William Brown

Introduction  – Changes and trends in Western Canadian agriculture  – DDGS use in rations  – Opportunities for development of the DDGS market in Western Canada  – Challenges of creating new markets – Emerging DDGS market – Knowledge gaps and future research needs – Conclusions – Bibliography

CHAPTER 27Biofuels: their co-products and water impacts in the context of life-cycle analysis 483

Michael Wang and Jennifer Dunn

Introduction – Biofuel production technologies – Market potential of biofuel co-products – Animal feed by-products of maize starch ethanol manufacturing – LCA of biofuels  – Co-products – Biofuel LCA results – Co-product allocation methodologies and impacts on LCA results  – Water consumption allocation between ethanol and co-products  – Knowledge gaps and future research needs  – Conclusions  – Acknowledgements  – Bibliography

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CHAPTER 28Utilization of co-products of the biofuel industry as livestock feeds – a synthesis 501

Tim Smith and Harinder Makka

Introduction – Background – Ethanol – Biodiesel – Micro-algae – Economics – Knowledge gaps and future research needs – Acknowledgements

Contributing authors 523

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Preface

Humans are faced with major environmental challenges as a result of climate change and a predicted shortage of fossil fuels for transport. The underlying causes of climate change are not fully understood, but it is accepted that greenhouse gas (GHG) emissions, especially methane, are a contributory fac-tor over which we can exert some control. The shortage of fossil fuels can be mitigated by blending them with biofuels, either ethanol with petrol, or biodiesel with diesel, both of which also result in a reduction in carbon emissions and for which minimum inclusion rates have been agreed. However, biofuel production is currently from agricultural crops, usually starch-containing cereals for ethanol and oilseeds for biodiesel. To be successful this approach must be economically sustainable and must not generate conflict with the traditional use of agricultural land in producing food and feed for humans and livestock. Both criteria can only be met if the residues of biofuel production, referred to as co-products, are fully utilized.

One of the objectives of producing this publication was to collate, discuss and summarize state-of-the-art knowledge on current and future availability of co-products from the feedstocks most used for the production of biofuels, and use of the co-products as livestock feed. The original feedstocks tended to be major agricultural crops, cereals, especially maize and wheat, and sugar cane for ethanol production, and soybean meal and rapeseed meal for biodiesel. An underlying feature has been the spread worldwide of an industry originally based in North America and Europe.

With an increasing need for biofuels and expanding markets for co-products, another objective was to summarize information on alternative feedstocks, with an emphasis on cellulosic materials and non-conventional sources. Many of these are grown on sub-prime land and have minimum requirements for irrigation and other inputs. Detoxification of some seed meals and cakes is necessary before they can be considered as feeds. With other crops, such as oil palm, promoting use of the residues and co-products available both from the field and processing is required. The potential contribution from micro-algae presents a new concept in that their production is not land-based and processing can be achieved through the use of coastal waters. Other developments include broadening of the use of co-products from ruminant, especially cattle, and pigs, to poultry and fish (aquaculture), enhancement of the availability of existing co-products, and the introduction of new ones.

The third objective of this publication was to identify gaps in knowledge and define research topics to fill them. Subjects predominating include standardization of product quality, needed to aid ration formulation; testing of new products; development of detoxification procedures; research on micro-algae; and life cycle analysis linked to traditional nutritional appraisal.

This publication covers a wide array of co-products and is a timely contribution as people’s aspira-tions are rising, evident from an increasing demand for livestock products and an ever greater reliance on transport, whether by air, road or sea, coupled with the challenge of maintaining agricultural production when faced with global warming. We hope that this publication will be useful to policy-makers, researchers, the feed industry, science managers and NGOs, and will contribute to making information-based decisions on issues related to food-feed-fuel competition and emerging challenges of global warming, in addition to making the efficient use of a wide range of co-products from the biofuel industry as livestock feed.

Berhe G. TekolaDirector

Animal Production and Health Division

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Acknowledgements

We would like to thank all those who contributed so diligently and excellently to the content of this document. In particular, thanks go to the many reviewers, who spent many hours in critically reviewing the contributions. We also thank Samuel Jutzi, Simon Mack and Philippe Ankers for their support for this work. The contributions of Thorgeir Lawrence, Claudia Ciarlantini, Chrissi Smith Redfern, Simona Capocaccia, Suzanne Lapstun and Myrto Arvaniti towards editing and layout setting processes are gratefully acknowledged.

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Abbreviations used in the text

A:P Acetate-to-propionate ratio

AA Amino acid

AAFCO American Association of Feed Control Officials

ABARE Australian Bureau of Agricultural and Resource Economics

ACC Australian Commercial Cross

ADF Acid-detergent fibre

ADFI Average daily feed intake

ADG Average daily gain

ADICP Acid-detergent-insoluble crude protein

ADIN Acid-detergent insoluble N

ADL Acid-detergent lignin

AFEX Ammonia fibre expansion

AFIA American Feed Industry Association

AI Artificial insemination

ALA Alpha-linolenic acid

Ala Alanine

ALP Alkaline phosphatase

AME Apparent metabolizable energy

AMEn Apparent metabolizable energy corrected for zero nitrogen deposition

AMTS Agriculture Modeling and Training Systems

APHIS Animal and Plant Health Inspection Service [USDA]

Arg Arginine

Asp Asparagine

AST Aspartate transaminase

ATNSKC Alkali-treated NSC

ATP Adenosine tri-phosphate

ATTD Apparent total tract digestibility

AUD Australian dollars

BLR Bagasse leaf residue

BN Binder treated

BOD Biological oxygen demand

BP Beet pulp

BRSL Bagasse residue and stripped leaves

BRSLB Bagasse plus stripped leaves-based feed block

BUN Blood urea nitrogen

BW Bodyweight

C/N Carbon:Nitrogen ratio

Ca Calcium

Ca(OH)2 Calcium hydroxide

CABI Commonwealth Agricultural Bureaux International

CB-1A Castor bean 1 allergen

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CBM Castor bean meal

CBS Cystathionine β-synthase

CCDS Maize [corn] condensed distillers solubles

CCK Cholecystokinin

CDO Cysteine dioxygenase

CDS Condensed distillers solubles

CF Crude fibre

CFB Commercial feed block

CFR Code of Federal Regulations

CGE Computable General Equilibrium

CIAT International Center for Tropical Agriculture

CLA Conjugated linoleic acid

CLAYUCA Latin American and Caribbean Consortium to Support Research and Development of Cassava

CO Carbon monoxide

CO2 Carbon dioxide

CP Crude protein

CPO Crude palm oil

CSE Cystathionine γ-ligase

CSIRO Commonwealth Scientific and Industrial Research Organisation

CSM Cotton seed meal

Cu Copper

Cys Cysteine

DCGF Dry maize [corn] gluten feed

DCP Digestible crude protein

DCU Decentralized crushing unit

DDG Dried distillers grain

DDGS Dried distillers grain with solubles

DE Digestible energy

DG Distillers grain

DGNC De-oiled groundnut cake

DGS Distillers grain with solubles

DHA Docosahexaenoic acid

DIM Days in milk

DIP Degradable intake protein

DJKM Detoxified jatropha kernel meal

DJPI Detoxified jatropha protein isolates

DJSM Detoxified jatropha seed meal

DKC De-oiled karanj cake

DM Dry matter

DMD Dry matter digestibility

DMI Dry matter intake

DNSC De-oiled neem seed cake

DNSM De-oiled neem seed meal

DRC Dry-rolled corn

EAA Essential amino acid

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EC European Commission

ED Effective protein degradability

EE Ether extract

EFB Empty fruit bunches

EIA United States Energy Information Administration

EJ Exajoule [1018 joules]

EKC Expeller-pressed karanj cake

Embrapa Empresa Brasileira de Pesquisa Agropecuária

EMS Ear-maize silage

EPA United States Environmental Protection Agency

EPA Eicosapentaenoic acid

ePURE European Renewable Ethanol Association

ERD Effective ruminal degradability

ERS Economic Research Service

ESR Erythrocyte sedimentation rate

ETOH Ethanol

EU European Union

FAO Food and Agriculture Organization of the United Nations

FAPRI Food and Agricultural Policy Research Institute

FASOM Forest and Agricultural Sector Optimization Model

FCE Feed conversion efficiency

FCM Fat-corrected milk

FCR Feed conversion ratio

FDA Food and Drug Administration [USA]

FEDNA Federación Española para el Desarrollo de la Nutrición Animal

FELCRA Federal Land Consolidated Authority

FELDA Federal Land Development Authority

FOBI Feed Opportunities from the Biofuels Industries

FQD Fuel Quality Directive [of the EU]

G:F Grain-to-feed ratio [feed efficiency]

GCAU Grain consuming animal unit

GE Gross energy

GHG Greenhouse gas

GHMC Ground high-moisture maize

GLA Gamma linolenic acid

Glu Glutamate

Gly Glycine

GNC Groundnut cake

GREET Greenhouse gases, regulated emissions, and energy use in transportation

GS Grass silage

GTAP Global Trade Analysis Project

H+ Hydrogen ion

H2S Hydrogen sulphide

H2S2O7 Thiosulphuric acid

H2SO3 Sulphurous acid

HC Hemicellulose

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HCHO Formaldehyde

HCl Hydrochloric acid

HCN Hydrogen cyanide

His Histidine

H-JPKM Heated Jatropha platyphylla kernel meal

HMC High moisture maize

HPDDG High-protein dried distillers grain

HPDDGS High-protein dried distillers grain with solubles

HRS Hard Red Spring [wheat]

HRW Hard Red Winter [wheat]

HS- Hydrosulphide ion

HS-SH Hydrogen persulphide

HUFA Highly unsaturated fatty acids

ICA Instituto Colombiano Agropecuario

ICAR Indian Council of Agricultural Research

ICOA International Castor Oil Association

ICRISAT International Crops Research Institute for the Semi-Arid Tropics

Ile Isoleucine

ILUC Indirect land use change

IMOD Inclusive market-oriented development

In vitro D In vitro digestibility

INRA Institut National de la Recherche Agronomique

IRR Internal Rate of Return

IU International Unit

IVOMD In vitro organic matter digestibility

JCM Jatropha curcas kernel meal

JPI Jatropha protein isolate

JPKM Jatropha platyphylla kernel meal

K+ Potassium ion

KK Kedah-Kelantan

KLPD Kilolitres per day

L Lightness or luminance

LANUR Laboratório de Nutrição de Ruminantes

LC50 Lethal concentration 50 percent

LCA Life-cycle Analysis

LD50 Lethal Dose 50 [dose lethal to 50% of recipients]

LDH Lactic dehydrogenase

LED Light-emitting diode

Leu Leucine

LM Lime treated

LPC Lupin protein concentrate

LSD Least Significance Difference

LSF Liquefaction, saccharification and conventional fermentation

LUC Land use change

LW Live weight

LWG Liveweight gain

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Lys Lysine

MARDI Malaysian Agricultural Research and Development Institute

masl Metres above [mean] sea level

MDA Malondialdehyde

MDGS Modified distillers grain with solubles

ME Metabolizable energy

Met Methionine

MJ Megajoule

MP Metabolizable protein

MPS Milk protein score

MS Maize silage

MST Mercaptopyruvate sulphurtransferase

MUFA Mono-unsaturated fatty acids

MUN Milk urea nitrogen

MWDGS Modified wet distillers grain with solubles

N Nitrogen

N2O Nitrous oxide

Na+ Sodium ion

NADPH Nicotinamide adenine dinucleotide phosphate (reduced)

NAIP National Agricultural Innovation Project

NaOH Sodium hydroxide

NBB National Biodiesel Board

NDF Neutral-detergent fibre

NDS Neutral-detergent solubles

NE Net energy

NEg Net energy for gain

NEL Net energy for lactation

NG Natural gas

NL Narrow-leaf

NNP Non-protein nitrogen

NO Nitrous oxide

NPV Net Present Value

NRC National Research Council [USA]

NRCS National Research Centre on Sorghum [India]

NREAP National Renewable Energy Action Plan

NSC Neem seed cake

NSKC Neem seed kernel cake

NSP Non-starch polysaccharide

NV Nutritive value

O2 Oxygen

OG Orchardgrass

OM Organic matter

OMD Organic matter digestibility

OPF Oil palm fronds

OPS Oil palm slurry

OPT Oil palm trunks

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P Phosphorus

Pb Plumbum [lead]

PCV Packed cell volume

PD Purine derivatives

PEM Polioencephalomalacia

PFAD Palm fatty acid distillates

Phe Phenylalanine

PJ Petajoule [1015 joules]

PKC Palm kernel cake

PKE Palm kernel expeller

PKM Palm kernel meal

PKO Palm kernel oil

POME Palm oil mill effluent

POS Palm oil sludge

PPC Potato protein concentrate

PPF Palm press fibre

Pro Proline

PUFA Polyunsaturated fatty acids

PV Peroxide value

RBC Red blood cell

RBD Refined Bleached De-odourized

RDP Rumen-degradable protein

RED Renewable Energy Directive [of the EU]

RFA Renewable Fuels Association

RFDGS Reduced-fat DDGS

RFS Renewable Fuel Standard

RHMC Rolled high-moisture maize

RIPs Ribosome-inactivating proteins

RISDA Rubber Industry Smallholders Development Authority

RSC Rapeseed cake

RSM Rapeseed meal

RUP Ruminally undegraded crude protein

RUSBI Rural Social Bio-refineries

S Sulphur

S= Sulphide ion

SBE Spent bleaching earth

SBM Soybean meal

SD Standard deviation

SDO Sulphur dioxygenase

SE Solvent-extracted

SEDC State Economic Development Corporation

Ser Serine

SFA Short-chain fatty acids

SFC Steam-flaked maize

SG Switchgrass

SGOT Serum glutamate-oxaloacetate transaminase

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SGPT Serum glutamate-pyruvate transaminase

SH Soybean hulls

SHF Simultaneous hydrolysis and fermentation

SID Standardized ileal digestibility

SKC Solvent-extracted karanj cake

SNF Solids not fat

SO2 Sulphur dioxide

SOC Soil organic carbon

SPC Soybean protein concentrate;

SPI Soy protein isolate

SQR Sulphide:quinone oxidoreductase

SQR-SSH SQR persulphide

SRC Short-rotation coppicing

SSB Sweet sorghum bagasse

SSF Solid state fermentation

T1 Treatment 1

T2 Treatment 2

TAB Treated alkali bagasse

TBARS Thiobarbituric acid reactive substances

TDF Total dietary fibre

TDN Total digestible nutrients

Thr Threonine

TJ Terajoule [1012 joules]

TME True metabolizable energy

TMP Total milk protein

TMR Totally mixed ration

toe Tonne oil equivalent

Trp Tryptophane

TS Total solids

TSS Total suspended solids

TVFA Total volatile fatty acids

Tyr Tyrosine

uCP Utilizable crude protein at the duodenum

UFPA Universidade Federal do Pará

UFRGS Universidade Federal do Rio Grande do Sul

UIP Undegradable intake protein

UMK Universiti Malaysia Kelantan

UMMB Urea molasses mineral blocks

UNDESA United Nations Department of Economic and Social Affairs

UNIDO United Nations Industrial Development Organization

UNSKC Urea-ammoniated neem seed kernel cake

UPM Universiti Putra Malaysia

USDA United States Department of Agriculture

Val Valine

VCA Value Chain Analysis

VFA Volatile fatty acid

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WBP Wet beet pulp

WCGF Wet maize gluten feed

WDG Wet distillers grain

WDGS Wet distillers grain with solubles

WDGSH Wet distillers grain+soy hulls blend

WPC Whole-plant maize

WTW Well-to-wheels

WWNSKC Water-washed NSKC

1

INTRODUCTION – THE CASE FOR EXPANDING BIOFUEL PRODUCTIONThe confluence of several economic, geopolitical and envi-ronmental factors in recent years has stimulated increased global interest in advancing the production and consump-tion of liquid biofuels for transportation. Historically, interest in biofuels has been primarily driven by national desires to enhance energy security and reduce dependency on fossil fuels. Through stimulation of demand for agricultural com-modities, biofuels have also been promoted as a means of enhancing rural economic development and increasing farm income. More recently, however, biofuels have been endorsed as a key component of national and international strategies to reduce greenhouse gas (GHG) emissions and mitigate poten-tial climate change effects. As seen in Figure 1, these factors have contributed to a significant increase in global biofuels production in recent years, with world output growing nearly five-fold between 2001 and 2009 (U.S. EIA, 2010).

Government policyIn an effort to decrease fossil fuel use, stimulate economic development and reduce GHG emissions, many national

governments have enacted policies in recent years that support increased domestic production and use of biofu-els. For example, Brazil mandates the minimum level of ethanol that must be blended with petrol. Brazil previous-ly provided subsidies to ensure the price of ethanol was below the price of petrol and required the nation’s largest petroleum company to purchase increasing amounts of ethanol (Hofstrand, 2009). Both Brazil and Argentina also have established programmes requiring that biodiesel be blended into petroleum diesel at specified levels. In the United States, Congress established a Renewable Fuel Standard (RFS) in 2005 requiring that petroleum refiners blend increasing volumes of renewable fuels, including biofuels like ethanol and biodiesel. The RFS was modified and expanded in the Energy Independence and Security Act of 2007, requiring petroleum refiners to use 136 bil-lion litres (36 billion gallons) of renewable fuels annually by 2022. The United States also provides fuel excise tax credits, which were scheduled to expire on 31 December 2011, to petrol and diesel fuel blenders who blend etha-nol and biodiesel. In the European Union, various member states have established mandates and provided fuel excise

Chapter 1

An outlook on world biofuel production and its implications for the animal feed industryGeoff Cooper1 and J. Alan Weber21 Renewable Fuels Association, 16024 Manchester Road, Suite 223, Ellisville, Missouri 63011, United States of America2 Marc-IV Consulting, Inc., 3801 Bray Court, Columbia, Missouri 65203, United States of America

E-mail for correspondence: gcooper@ethanolrfa.org

ABSTRACT Many countries have adopted policies that support expanded production and use of liquid biofuels for transporta-

tion. These policies are intended to enhance domestic energy security, spur economic development and reduce

emissions of greenhouse gases (GHG) and other pollutants. Biofuel policies, along with changing energy market

fundamentals, have contributed to a significant increase in global biofuel production in recent years. While con-

siderable research and development is under way to commercialize new types of biofuel and feedstocks, the two

primary biofuels produced globally today – ethanol and biodiesel – are predominantly derived from agricultural

commodities, such as grain, sugar and oilseeds. The use of certain feedstocks for biofuels production also results in

the co-production of animal feed. Globally, these animal feed co-products are growing in volume and importance.

The increased use of agricultural commodities for biofuels is generally expected to contribute to marginally higher

costs for certain livestock and poultry feeds, though the impacts are shown by the literature to be modest in nature

and there are offsetting effects. Increased substitution of co-products for traditional feedstuffs in feed rations helps

mitigate potential input cost increases faced by livestock and poultry producers. Further, increased agricultural

productivity and output has ensured that the global supply of crops available for non-biofuels uses has continued

to grow in the long term. Growth in the use of agricultural commodities for biofuels is expected to continue in the

next 10 years, but with growth rates slowing in key producing countries as government-imposed limits on grain

use for biofuels are reached and new non-agricultural feedstocks are commercialized.

Biofuel co-products as livestock feed – Opportunities and challenges2

tax exemptions to encourage biofuels use. Additionally, a 2003 European Commission (EC) directive called for member states to ensure biofuels represented 2  per-cent of petrol and diesel fuel consumption by 2005 and 5.75  percent by 2010. A 2009 EC directive established that 10 percent of energy used for transportation in the European Community by 2020 must derive from renew-able sources, such as biofuels. Many other countries, including Canada, China, India, Japan and South Africa,

have in recent years enacted blending requirements or other policies supporting biofuels production and use (Nylund et al., 2008).

Energy market factorsWhile government policy has played an important role in stimulating growth in global biofuels production and con-sumption, demand for biofuels also has been accelerated by global economic and energy market forces. Declining

FIGURE 1 2001–2009 global biofuels production by nation or region

Source: U.S. EIA, 2010

• Biofuels policies, along with changing energy mar-

ket fundamentals, have contributed to a significant

increase in global biofuel production in recent years.

• The two primary biofuels produced globally today –

ethanol and biodiesel – are predominantly derived

from agricultural commodities, such as grain, sugar

and oilseeds.

• The increased use of agricultural commodities for bio-

fuel is generally expected to contribute to marginally

higher feed prices for livestock and poultry producers,

though the impacts are shown by the literature to be

modest in nature.

• Increased substitution of co-products for traditional

feedstuffs in feed rations helps mitigate potential

input cost increases faced by livestock and poultry

producers.

• Increased agricultural productivity and output has

ensured that the global supply of crops available for

non-biofuel uses has continued to grow over the long

term.

• Growth in the use of agricultural commodities for

biofuel production is expected to continue in the next

10 years, but growth rates are expected to slow in key

producing countries as government-imposed limits

on grain use for biofuels are reached and new non-

agricultural feedstocks are commercialized.

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An outlook on world biofuel production and its implications for the animal feed industry 3

global crude oil productive capacity coupled with growing demand, particularly in developing nations, has led to high-er crude oil prices in recent years. As such, biofuels from a variety of feedstocks have become more economically competitive with petroleum-based fuels. Long-term energy supply and demand forecasts generally indicate sustained increases in world crude oil prices (U.S. EIA, 2011), sug-gesting improved economic competitiveness for biofuels. If global crude oil prices remain at historically elevated levels, and if feedstock prices decline from the weather-related highs of 2010/2011, biofuel production in many countries could exceed the volumes specified by national policies and directives based purely on its economic competitiveness with petroleum-based fuels (Hayes, 2008).

COMMON BIOFUELS, FEEDSTOCKS AND CO-PRODUCTS Two biofuels – ethanol (ethyl alcohol) and biodiesel from fatty acid methyl esters – account for the vast majority of global biofuel production and use today. These biofuels are made today primarily from agricultural commodities, such as grain and sugar (ethanol) and vegetable oil (biodiesel). Significant research and development efforts are under way to commercialize new biofuels (e.g. butanol) and new feed-stocks (e.g. cellulosic agricultural residues, municipal solid waste, algae, etc.) (Solomon, Barnes and Halvorsen, 2007). However, these “next generation” feedstocks and biofuels are unlikely to be produced in quantity in the short term according to most projections (U.S. EIA, 2011). Further, the co-products from many of these new feedstocks are not likely to have applications in the animal feed market, at least initially. Thus, the primary focus of this paper is on cur-rent ethanol and biodiesel feedstocks and the co-products that result from common processing methods.

Ethanol feedstocks and processesEthanol is a petroleum petrol replacement produced today mainly from grains and sugar cane. Other less common feedstocks include sugar cane and beet molasses, sugar beets, cassava, whey, potato and food or beverage waste. In 2010, approximately 87 billion litres (23 billion gallons) of ethanol were produced, with the United States, Brazil, and the European Union accounting for 93% of this output (RFA, 2011a).

GrainsGrains such as maize, wheat, barley and sorghum are com-mon feedstocks for ethanol production, and to a lesser extent are also rye, triticale, sorghum [milo] and oats. The grain ethanol process is generally the same for all of these grain feedstocks, though there are some slight differences and the co-product characteristics vary somewhat depend-ing on the grain used.

Two processes are primarily used to make ethanol from grains: dry milling and wet milling. In the dry milling proc-ess, the entire grain kernel typically is ground into flour (or “meal”) and processed without separation of the various nutritional component parts of the grain. The meal is slur-ried with water to form a “mash”. Enzymes are added to the mash, which is then processed in a high-temperature cooker, cooled and transferred to fermenters where yeast is added and the conversion of sugar to ethanol begins. After fermentation, the resulting “beer” is transferred to distillation columns where the ethanol is separated from the residual “stillage”.

The stillage is sent through a centrifuge that separates the solids from the liquids. The liquids, or solubles, are then concentrated to a semi-solid state by evaporation, result-ing in condensed distillers solubles (CDS) or “syrup”. CDS is sometimes sold direct into the animal feed market, but more often the residual coarse grain solids and the CDS are mixed together and dried to produce distillers dried grain with solubles (DDGS). In the cases where the CDS is not re-added to the residual grains, the grain solids product is simply called distillers dried grain (DDG). If the distillers grain is being fed to livestock in close proximity to the etha-nol production facility, the drying step can be avoided and the product is called wet distillers grain (WDG). Because of various drying and syrup application practices, there are several variants of distillers grain (one of which is called modified wet distillers grain), but most product is marketed as DDGS, DDG or WDG.

Some dry-mill ethanol plants in the United States are now removing crude maize oil from the CDS or stillage at the back end of the process, using a centrifuge. The maize oil is typically marketed as an individual feed ingredient or sold as a feedstock for further processing (e.g. for biodiesel production). The co-product resulting from this process is colloquially known as “oil extracted” DDGS or “de-oiled” DDGS. These co-products typically have lower fat content than conventional DDGS, but slightly higher concentrations of protein and other nutrients.

A very small number of dry-mill plants also have the capacity to fractionate the grain kernel at the front end of the process, resulting in the production of germ, bran, “high-protein DDGS” and other products (RFA, 2011b). In some cases, ethanol producers are considering using the cellulosic portions of the maize bran as a feedstock for cellulosic ethanol. The majority of grain ethanol produced around the world today comes from the dry milling process.

In the wet milling process, shelled maize is cleaned to ensure it is free from dust and foreign matter. Next, the maize is soaked in water, called “steepwater”, for between 20 and 30 hours. As the maize swells and softens, the steepwater starts to loosen the gluten bonds with the maize, and begins to release the starch. The maize goes on

Biofuel co-products as livestock feed – Opportunities and challenges4

to be milled. The steepwater is concentrated in an evapora-tor to capture nutrients, which are used for animal feed and fermentation. After steeping, the maize is coarsely milled in cracking mills to separate the germ from the rest of the components (including starch, fibre and gluten). Now in a form of slurry, the maize flows to the germ separators to separate out the maize germ. The maize germ, which con-tains about 85 percent of the maize’s oil, is removed from the slurry and washed. It is then dried and sold for further processing to recover the oil. The remaining slurry then enters fine grinding. After the fine grinding, which releases the starch and gluten from the fibre, the slurry flows over fixed concave screens which catch the fiber but allow the starch and gluten to pass through. The starch-gluten sus-pension is sent to the starch separators. The collected fibre is dried for use in animal feed.

The starch-gluten suspension then passes through a centrifuge where the gluten is spun out. The gluten is dried and used in animal feed. The remaining starch can then be processed in one of three ways: fermented into ethanol, dried for modified maize starch, or processed into maize syrup. Wet milling procedures for wheat and maize are somewhat different. For wheat, the bran and germ are generally removed by dry processing in a flour mill (leaving wheat flour) before steeping in water.

In 2010, an estimated 142.5 million tonne of grain was used globally for ethanol (F.O. Licht, 2011), representing 6.3 percent of global grain use on a gross basis (Figure 2). Because roughly one-third of the volume of grain proc-essed for ethanol actually was used to produce animal feed, it is appropriate to suggest that the equivalent of 95 million tonne of grain were used to produce fuel and the remaining equivalent 47.5  million tonne entered the feed market as co-products. Thus, ethanol production rep-resented 4.2 percent of total global grain use in 2010/11 on a net basis. The United States was the global leader in grain ethanol production, accounting for 88  percent of total grain use for ethanol. The European Union accounted for 6 percent of grain use for ethanol, followed by China (3.4 percent) and Canada (2.3 percent). The vast majority of grain processed for ethanol by the United States was maize, though grain sorghum represented a small share (approximately 2 percent). Canada’s industry primarily used wheat and maize for ethanol, while European producers principally used wheat, but also processed some maize and other coarse grains. Maize also accounted for the majority of grain use for ethanol in China.

Sugar caneAside from grains, sugar cane is the other major ethanol feedstock in wide use today, particularly in tropical or sub-tropical regions. Sugar cane is typically processed by mills that are capable of producing both raw sugar and ethanol.

In the sugar cane ethanol process, mills normally wash incoming sugar cane stalks to remove soil and other debris. Washing is followed by a process known as “breaking,” in which cane stalks are crushed to expose sugar-rich fibres. These fibres are then mechanically pressed to extract sugars and form sugar “juice”. At most facilities, the juice typically is then divided into two streams: one stream for raw sugar production and the other stream for ethanol fermenta-tion. For the stream dedicated to ethanol production, sus-pended materials are strained out of the juice, followed by another refining step known as the “clarification” process. The clarified sugar juice typically is then concentrated via evaporation. Next, clarified and concentrated sugar juice is fermented and distilled into alcohol.

The fibrous residue remaining after sugars are extracted is known as “bagasse”. Whereas the co-products of grain ethanol are used primarily as animal feed, bagasse is used predominantly as a fuel source to generate steam and elec-tricity to operate the sugar mill. Some research has been con-ducted on using bagasse as a feed ingredient for cattle, but this is a rare application with limited commercial acceptance.

In 2010, more than 98 percent of the world’s sugar cane ethanol output came from Brazil, while Colombia provided 1 percent. A total of 292.3 million tonne of sugar cane was processed for ethanol in 2010 (F.O. Licht, 2011).

Sugar beetThough far less common than grains or sugar cane, sugar beet is occasionally used as an ethanol feedstock. The

FIGURE 22010 world feedstock usage for fuel ethanol

(thousand tonne)

Notes: *Grain use reported on gross basis. Approximately one-third of grain for fuel ethanol produces animal feed co-products.Source: F.O. Licht, 2011

292 300

142 500

18 400

6 900 1 280680

Sugar cane

Cane/beet molasses

Sugar beet

Fresh cassavaOther (whey, beverage waste, etc.)

Grains (gross)*

An outlook on world biofuel production and its implications for the animal feed industry 5

process and technology used to convert sugar beet into ethanol is quite similar to the sugar cane ethanol process. However, the fibrous component of the sugar beet that remains after sugars are extracted (known as “beet pulp”) is most often dried and marketed as an animal feed ingredient. Currently, the use of sugar beet for ethanol occurs mainly in the European Union. An estimated 6.9  million tonne of sugar beet was used for ethanol in 2010 ( F.O. Licht, 2011).

Sugar cane and beet molassesMolasses is a by-product of raw sugar production from sugar cane and beets. It contains minerals regarded as impurities in the raw sugar, but also retains some fer-mentable sugars. Molasses has generally been used as an animal feed ingredient, but is also used as a feedstock for ethanol production in facilities that have integrated sugar and ethanol production capabilities. Fermentation of the sugars found in molasses is conducted in a manner similar to fermenting sugars from other feedstocks. An estimated 18.4 million tonne of molasses was processed into fuel eth-anol in 2010, with Brazil representing 74 percent of total use, followed by Thailand (7 percent) and India (5 percent) (F.O. Licht, 2011).

CassavaCassava, also known as tapioca, is an annual crop that is cultivated in tropical regions. The cassava root has rela-tively high starch content, making it a suitable feedstock for ethanol fermentation. It is typically available in two forms for ethanol production: fresh root (high moisture, available seasonally) and dried chips (low moisture content, avail-able throughout the year). When processing fresh root, the feedstock is washed to remove soil and debris, followed by peeling. The peeled root is then subjected to a process known as rasping, which breaks down cell walls to release starch granules. The starch is then steeped and separated from the fibrous residue and concentrated. Next, the starch is fed into the fermentation process, followed by distilla-tion and dehydration, similar to the process for grain-based ethanol. The co-product of the cassava-to-ethanol process is root fibre, which is used as a boiler fuel source, similar to bagasse in the sugar cane ethanol process. Root fibre is not currently used as animal feed.

In 2010, the equivalent of nearly 1.3 million dry tonne of fresh cassava root was processed into ethanol. Thailand was the leading producer (50 percent), followed by China (44 percent) (F.O. Licht, 2011).

Small amounts of other feedstocks, such as cheese whey, potato and beverage waste, were probably used in 2010, but they are not discussed here because of their insignificant volumes and hence impact on global feed markets.

Biodiesel feedstocks and processesBiodiesel is a petroleum diesel fuel replacement produced from renewable fats and oils sources such as vegetable oils, animal fats and recycled cooking oils. Chemically, biodiesel is a mono-alkyl ester of long chain fatty acids. It is produced from a diverse set of feedstocks, reflecting the natural fats or oils indigenous to specific geographical regions. Thus, European biodiesel producers rely upon rapeseed as a pri-mary feedstock for biodiesel production. In Southeast Asia, crude palm oil or its derivatives are the primary feedstocks utilized. Meanwhile, in the United States, soybean oil is the predominant feedstock, although a host of other feed-stocks, such as animal fats, yellow grease, and vegetable oil recovered from dry mill ethanol plants, contribute supplies as well.

It is estimated that global production of biodiesel in 2010 was 17.9  million tonnes (5.34  billion gallons) (Oil World, 2011). Production is expected to increase 17  per-cent in 2011 to 21 million tonne (6.3 billion gallons). The European Union was the global leader in biodiesel produc-tion in 2010, accounting for an estimated 52  percent of production. Almost 80 percent of the anticipated produc-tion in 2011 will be generated by the EU, United States, Argentina and Brazil.

OilseedsOilseeds such as rapeseed or canola and soybeans repre-sent the most common source of vegetable oil feedstocks for biodiesel production. The biodiesel production process utilized for these feedstocks is similar. In 2010, an estimated 5.8 million tonne of rapeseed or canola oil and 5.7 million tonne of soybean oil were used globally in the production of biodiesel, representing 69 percent of the total feedstocks used in global biodiesel production (Figure 3).

PalmGlobally, palm oil is an important vegetable oil source. A unique feature of the palm tree is that it produces two types of oil; crude palm oil from the flesh (mesocarp) of the fruit, and palm kernel oil from the seed or kernel. The crude palm oil may be further refined to get a wide range of palm products of specified quality. For example, palm oil may be fractionated to obtain solid (stearin) and liquid (olein) fractions with various melting characteristics. The different properties of the fractions make them suitable for a variety of food and non-food uses.

In 2010, an estimated 2.4  million tonne of palm oil were used globally in the production of biodiesel (F.O. Licht, 2011), representing 15 percent of the total feedstocks used in global biodiesel production. Indonesia, Thailand, the EU and Colombia were the top users of palm oil for biodiesel production in 2010. Together, they represented 78 percent of global use of palm oil for biodiesel.

Biofuel co-products as livestock feed – Opportunities and challenges6

Animal fats and yellow greaseAnimal fats are derived from the rendering process using animal tissues as the raw material. The raw material is a by-product of the processing of meat animals and poultry. The amount of fat produced is directly related to the species of animal processed and the degree of further processing that is associated with the marketing and distribution of the meat product. Current markets for rendered animal fats include use as feed ingredients for livestock, poultry, com-panion animals and aquaculture. In addition, products such as edible tallow are used for soap and fatty acid production. Industry analysts anticipate that roughly 25 to 30 percent of the rendered animal fat supplies could be diverted to biodiesel production given current uses (Weber, 2009).

In 2010, an estimated 2.2 million tonne of animal fats and yellow grease was used globally in the production of biodiesel (F.O. Licht, 2011), representing 14 percent of the total feedstocks used in global biodiesel production. EU producers used 54 percent of animal fats and yellow grease processed as biodiesel feedstock in 2010, followed by Brazil (16 percent) and the United States (12 percent).

Maize oil from ethanol production processesGrain ethanol production may offer the biodiesel industry its nearest-term opportunity for a significant additive sup-ply of plant oils for biodiesel production. Historically, maize oil has not been a viable biodiesel feedstock due to its relative high cost and high value as edible oil. However, as discussed earlier, some dry-mill ethanol plants in the United

States are now removing crude maize oil from the stillage at the back end of the process. The maize oil is typically marketed as an individual feed ingredient or sold as a feed-stock for further processing (e.g. for biodiesel production). Maize oil could help to meet feedstock market demand in two ways. First, edible maize oil could displace other edible oils that could then be diverted to biodiesel production. Second, non-edible maize oil could be used directly for biodiesel production.

Biodiesel production processRegardless of the feedstock, most biodiesel globally is pro-duced using one of three common manufacturing meth-ods: reaction of the triglycerides with an alcohol, using a base catalyst; reaction of the triglycerides with an alcohol, using a strong acid catalyst; or conversion of the triglycer-ides to fatty acids, and a subsequent reaction of the fatty acids with an alcohol using a strong acid catalyst.

In the United States and elsewhere, biodiesel is com-monly produced using the base-catalyzed reaction of the triglycerides with alcohol. Methanol is currently the main alcohol used commercially for the production of biodiesel due to its cost relative to other alcohols, shorter reaction times compared with other alcohols, and the difficulty and cost of recycling other alcohols.

Use of acid catalysis is typically limited to the conversion of the fatty acid fraction in high free fatty acid feedstocks, or to treat intermediate high fatty acid/ester streams that can form in the acidification of the crude glycerin bottoms produced as a co-product of the transesterification reaction.

Stoichiometrically, 100  kg of triglycerides are reacted with 10  kg of alcohol in the presence of a base catalyst to produce 10  kg of glycerin and 100  kg of mono-alkyl esters or biodiesel. In practice, an excess amount of alco-hol is used in the reaction to assist in quick and complete conversion of the triglycerides to the esters, and the excess alcohol is later recovered for re-use. All reactants must be essentially free from water. The catalyst is usually sodium methoxide, sodium hydroxide or potassium hydroxide that has already been mixed with the alcohol.

In some cases, the free fatty acid levels of the feed-stock utilized are elevated to the point that an esterifica-tion step, using an acid catalyst, is incorporated into the biodiesel processing sequence. This stage involves mixing the high fatty acid material with a solution of methanol that contains an acid catalyst, typically sulphuric acid. The contained fatty acids are then converted to methyl ester. An excess of methanol and H2SO4 is employed to ensure conversion, and after reaction completion this excess is separated from the ester phase. The conversion of the fatty acid to ester results in the formation of water, thus after the reaction there is water in the methanol+sulphuric acid mixture. Since this is an equilibrium reaction, the presence

FIGURE 32010 world feedstock usage for biodiesel

(thousand tonnes)

Source: F.O. Licht, 2011

Rapeseed oil

Soybean oil

Palm oil

Animal fats & yellow grease

Sunflower oil

Other

5 750

5 700

2 440

2 230211 161

An outlook on world biofuel production and its implications for the animal feed industry 7

of excessive amounts of water will adversely affect the con-version of the fatty acid to ester. Thus, a portion (or all) of the methanol+sulphuric acid mix is purged from the system and treated to recover the methanol and reject the water. A typical approach involves using this purge material as the acidifying agent for treating the glycerin material, followed by recovery of the methanol. In this case, the water fraction will end up in the glycerin phase.

Biodiesel co-productsThe main direct co-product of biodiesel production is glycerine, which is a commonly used commercial name for products whose principal component is glycerol. More precisely, however, glycerine applies to purified commercial products containing 95% or more of glycerol. Glycerine is a versatile and valuable chemical substance with many appli-cations. A clear, odourless, viscous liquid with a sweet taste, glycerine is derived from both natural and petrochemical feedstocks. It occurs in combined form (triglycerides) in all animal fats and vegetable oils and constitutes about 10 per-cent of these materials on average. Importantly, glycerine can also be utilized as a feed ingredient for livestock rations. Increased production of biodiesel has led to renewed evalu-ation of glycerine from biodiesel operations as a liquid feed ingredient for livestock.

In the conventional glycerine refining processes, the crude glycerine solution is initially treated with additional chemicals to remove any dissolved fatty acids or soaps, and to prepare the solution for the next stage of processing. The concentrated glycerine is then processed in a higher temperature, high vacuum distillation unit. The condensed glycerine solution is further treated to remove traces of residual fatty acids, esters or other organics that may impart colour, odour or taste to the glycerine. Typical methods for this “post-treatment” step may include activated clay addi-tion and filtration, similar to that used in the treatment of vegetable oils for edible uses; powdered activated carbon addition, followed by filtration; and/or treatment in acti-vated carbon columns, commonly used for trace organics removal from a range of industrial and food chemicals.

In the processing of biodiesel crude glycerine, issues typically associated with conventional crude processes, e.g. char materials, crystallized salts, etc., can be magnified, due to the higher starting impurity content. Thus, for a refin-ery that would process biodiesel crude only, or as a high percentage of its input, a more sophisticated processing approach may be required.

Another co-product of the biodiesel production process is fatty acids, which are derived from a variety of fats and oils, and are used directly (unreacted) or for the manufac-ture of derivatives. Fatty acids are used directly in a number of products such as candles, cosmetics and toiletries, animal feeds, lubricants and asphalt.

Vegetable oil meal represents a very important indirect co-product of biodiesel production. Oilseed crops that are crushed, either in a mechanical expelling or solvent extrac-tion operation, will generate both crude vegetable oil and oilseed meal. Oilseed meals are an integral component of livestock rations as a source of protein and key amino acids. Although soybean oil is the most valuable part of the seed on a per weight basis, only 20 percent of the seed by weight is vegetable oil. The remaining 80  percent of the seed (the portion left after extracting the oil) is referred to as “meal”. The value of oilseed meal in the animal feed market has historically been the primary economic driver of oilseed crushing, rather than the value of the oil. In other words, oilseed meal for livestock feed is the primary co-product of oilseed crushing, while vegetable oil is the secondary co-product. Thus, oilseed meal would be pro-duced for feed regardless of the uses and demand for the oil. Accordingly, oilseed meal is not considered a direct co-product of biodiesel production.

GENERALLY ACCEPTED USES OF FEED CO-PRODUCTS IN ANIMAL DIETSBiofuel co-products are used broadly today as feed ingre-dients in the diets for livestock, poultry and fish. These co-products often substitute for higher priced feeds in animal rations. For example, in recent years, DDGS has sold at a significant discount to maize and soybean meal, which are the ingredients it primarily substitutes for in animal diets (Hoffman and Baker, 2010). Ruminant animals, such as beef cattle and dairy cows, have been the main consum-ers of ethanol and biodiesel co-product feeds historically. However, the use of feed co-products in rations for non-ruminant animals, such as hogs and broilers, has been growing in recent years.

Numerous studies have examined the use of bio-fuel co-products in animal feed rations and identified key considerations for different animal species (Shurson and Spiehs, 2002; Anderson et al., 2006; Whitney et al., 2006; Daley, 2007; Klopfenstein, Erickson and Bremer, 2008; Schingoethe, 2008; Stein, 2008; Bregendahl, 2008; Walker, Jenkins and Klopfenstein, 2011). The amount of co-products that can be introduced into animal feed rations depends on the nutritional characteristics of the individual ingredient and unique limiting factors for the various spe-cies being fed.

Other papers have examined the mass of traditional feedstuffs displaced from typical animal feed rations by a given mass of biofuel co-products, such as distillers grain. Some of these papers show that due to the concentration of certain nutritional components, a given mass of distill-ers grains can displace more than the equivalent mass of maize and soybean meal in some animal rations. Arora, Wu and Wang (2008), for example, found that 1kg of

Biofuel co-products as livestock feed – Opportunities and challenges8

distillers grain can displace 1.2  kg of maize in a typical beef ration. Hoffman and Baker (2011) found that “…in aggregate (including major types of livestock/poultry), a metric ton of DDGS can replace, on average, 1.22 metric tons of feed consisting of maize and soybean meal in the United States.”

In general, studies show that distillers grains can account for approximately 30 to 40 percent in beef cattle rations, although higher rates can be used (Vander Pol et al., 2006). Animal feeding studies generally indicate effec-tive distillers grain inclusion rates of 20 to 25 percent for dairy cows, 20  percent for farrow-to-finish hogs, and 10 to 15 percent for the grow-finish stages of poultry feeding. Gluten feed from wet mills is typically fed to beef cattle at an inclusion rate of 30 to 50 percent of the ration, while gluten meal is fed at much lower levels to both ruminant and non-ruminant animals. Gluten meal is also a common ingredient in pet food products. Pressed or shredded beet pulp is typically fed to ruminant animals at no more than 15 to 20 percent of the diet. Glycerine from the biodiesel proc-ess can be added to beef and dairy diets at low levels, typi-cally representing no more than 10 percent of the ration. Research is also under way to determine appropriate levels of glycerine inclusion in swine and poultry rations (Flores and Perry, 2009).

HISTORICAL VOLUMES OF FEED FROM BIOFUEL CO-PRODUCTS Currently, there are no regular or comprehensive efforts to collect and report data on biofuel feed co-product produc-

tion volumes. However, several studies have approximated co-product output volumes, based on generally accepted conversion factors per tonne of feedstock and government estimates of feedstock use for biofuel production (Hoffman and Baker, 2010). As a general rule of thumb, a tonne of grain processed by an ethanol biorefinery will generate approximately one-third of a tonne of feed co-products. Thus, global grain ethanol co-product production can be estimated (Figure 4) by applying this simple conversion to estimates of total feedstock use, as provided by F.O. Licht (2011).

As most of the world’s grain ethanol output comes from the United States, most of the world’s DDGS and other feed co-products also originate in the United States. In recent years, as much as 25 percent of U.S. feed co-product out-put has been exported.

The amount of crude glycerine generated by the biodie-sel industry is directly proportional to overall biodiesel pro-duction. Generally about 10 percent, by weight, of the lipid source will be glycerine. In reality, approximately 0.4 kg of glycerine are produced per litre of biodiesel production. An economic analysis prepared by IHS Global Insight suggests expected biodiesel feedstock supplies in the United States could support 9.5  billion litres of biodiesel by 2015 (IHS Global Insight, 2011).

With increased production of biodiesel and a result-ant increase in crude glycerine supplies, it is likely that expanded feed applications will continue to be pursued. A 2010 survey of National Biodiesel Board (NBB) member companies reported that 48 percent of NBB members sold

FIGURE 4 Global production of grain ethanol animal feed co-products

Source: RFA calculation based on F.O. Licht, 2011

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An outlook on world biofuel production and its implications for the animal feed industry 9

their glycerine output to refiners to be processed for high-value uses, 33 percent marketed glycerine to be used for livestock feed, 4 percent sold the co-product as fuel, and the remaining survey respondents either did not specify a use or listed a minor use.

Impacts on global livestock and poultry marketsNumerous studies have examined the potential impacts of increased biofuels production on animal feed supplies and prices, as well as the production levels and prices of meat, milk, eggs and other agricultural products (Taheripour, Hertel and Tyner, 2010a, b; Elobeid et al., 2006; Banse et al., 2007; Birur, Hertel and Tyner, 2007; Westcott, 2007; USDA, 2007). Many of these studies have employed computable general equilibrium (CGE) or partial equilibrium economic models to estimate the potential long-term impacts of biofuel policies. While most of these studies suggest that large-scale bio-fuel production results in higher long-term prices for certain agricultural commodities (thus increasing input costs for the livestock and poultry industries), the magnitude of the impacts is generally modest. For example, in its analysis of the impacts of the United States’ Renewable Fuel Standard (RFS), the U.S. Environmental Protection Agency (EPA, 2010) found that full implementation of the programme’s biofuel consumption mandates might result in price increases of just 0.8% for soybeans, 1.5% for soybean oil and 3.1% for maize by 2022 over a baseline scenario with no biofuels mandate. Similarly, one recent study indicated that, from 2005 to 2009, prices for rice, wheat, soybean and maize would have been only marginally lower (-0.2, -1.3, -1.7 and -3.3 percent on average, respectively) if U.S. ethanol policies had not existed (Babcock, 2011).

Most of these studies indicate that the production and consumption of meat, milk, eggs and other agricultural goods may be slightly reduced due to higher feed input costs induced by biofuels expansion, but again, the impacts are found to be small. For example, the U.S. Environmental Protection Agency found that full implementation of the RFS biofuel consumption mandates could be expected to result in just a 0.05% reduction in consumption of livestock products and 0.03% reduction in consumption of dairy products by 2022 (EPA, 2010). In an analysis of the agricul-ture market impacts of achieving the 2015 RFS mandate for conventional (maize starch) biofuels, the U.S. Department of Agriculture (USDA) found no change in U.S. chicken output, an average -0.2% reduction in milk output and an average -0.3% reduction in pork output over baseline values between 2007 and 2016 (USDA, 2007). Beef output actually increased an average of 0.1% in the USDA analy-sis, as beef cattle production was assumed to benefit from increased production of distillers grain.

While the results of these economic analyses are instruc-tive, many of the studies have failed to properly incorporate

the recent economic impacts of increased consumption of biofuels co-products by the livestock and poultry sec-tor (Taheripour, Hertel and Tyner, 2010b). In recent years, prices for biofuel feed co-products have generally declined relative to competing feedstuffs, which is not accurately accounted for in most economic modelling studies exam-ining adjustments by the livestock and poultry sectors in response to increased biofuel production. Recent pricing patterns indicate that biofuel co-products can help the livestock and poultry industry offset minor cost increases for traditional feedstuffs that might result from expanded bio-fuel demand. Many of the economic modelling studies dis-cussed here were conducted prior to the establishment of sustained price discounts for key biofuel feed co-products relative to traditional feedstuffs.

Recognizing this shortcoming in previous modelling efforts, Taheripour, Hertel and Tyner (2010a) introduced an improved co-product substitution methodology to the Global Trade Analysis Project (GTAP) model, a popular CGE model used by government agencies and other entities in the U.S., EU, and Brazil. Based on the improved methodol-ogy and updated modelling results, Taheripour, Hertel and Tyner (2010b) concluded that “In general, the livestock industries of the US and EU do not suffer significantly from biofuel mandates, because they make use of the biofuel byproducts to eliminate the cost consequences of higher crop prices”. The study further found that “…while biofuel mandates have important consequences for the livestock industry, they do not harshly curtail these industries. This is largely due to the important role of by-products in substi-tuting for higher priced feedstuffs”.

While Taheripour, Hertel and Tyner (2010a) repre-sented an advancement in the analysis of the impact of expanded biofuels production on livestock, it did not take into account the ability of DDGS to displace more than an equivalent mass of maize and soybean meal, as document-ed by Arora, Wu and Wang (2008) and Hoffman and Baker (2011). Nor did the Taheripour study account for likely continued improvements in the feed conversion efficiency of livestock and poultry.

Specifically pertaining to biodiesel production, research has been conducted to evaluate the impact of increased biodiesel production from oilseeds on the livestock sector (Centrec, 2011). Utilizing a partial equilibrium model called the Value Chain Analysis (VCA) developed for the United Soybean Board, the impacts of single soybean oil supply or demand factors were examined in isolation from other factors. A decrease in soybean oil demand for biodiesel was isolated and analysed. The analysis found that reduced demand for soybean oil for United States biodiesel pro-duction would result in lower soybean oil prices, reduced soybean production and significantly higher soybean meal prices. Thus, the analysis showed that increased demand

Biofuel co-products as livestock feed – Opportunities and challenges10

for vegetable oil for biodiesel results in larger supplies of oilseed meal for livestock feed and, in turn, lower prices.

The results of the Centrec work were confirmed in 2011 in an economic analysis conducted by IHS Global Insight (2011) that analysed United States and international feedstock supplies, projected petroleum pricing, edible oil demand, and energy policy to estimate potential biodiesel industry growth in the United States. Potential acreage shifts, commodity price impacts, and global trade effects were also examined. The analysis demonstrated a sig-nificant decrease in soybean meal values due to increased oilseed production.

Aside from the effect of substituting relatively lower-cost feed co-products from biofuels production for tradi-tional feedstuffs, the modest impacts of expanded biofuels production on the livestock sector can be partially explained by steadily increasing supplies of food and feed crops. That is, the global grain and oilseed supply has grown sub-stantially in recent years, such that increased use of these commodities for biofuels production has not led to reduced availability for feed or feed use.

As an example, the global grain supply (wheat, rice, maize, sorghum, barley, oats, rye, millet and mixed grains) totalled 2  423  million tonne in 2005/06. Grain use for ethanol and co-product production was 54  million tonne on a gross basis in 2005/06 (F.O. Licht, 2011), meaning 2  369  million tonne of grain remained available for uses other than ethanol and feed co-products. By comparison, the global grain supply was a record 2 686 million tonne in 2009/10. Grain use for ethanol and co-products totalled 143 million tonne in 2009/10, meaning 2 543 million tonne of grain were available for non-ethanol uses. Thus, the supply of grain available for non-ethanol uses (i.e. grain remaining after accounting for grain use for ethanol) grew 7  percent between 2005/06 and 2009/10. Further, the supply of grain ethanol feed co-products grew 268  per-cent during this period. The combined supply of grain for non-ethanol use and ethanol feed co-products totalled 2 586 million tonne in 2009/10, compared with 2 386 mil-lion tonne in 2005/06. Figure 5 shows recent growth in the global grain supply relative to grain use for ethanol and feed co-product production.

The amount of grain available for uses other than etha-nol production is expected to grow more significantly in the long term, as grain use for ethanol moderates in accord-ance with slowing national mandates.

BIOFUELS AND CO-PRODUCT OUTLOOK TO 2020Market factors and government policies are expected to continue to support expanded biofuels production and use in the long term. Growth in grain and oilseed use for biofuels is expected to be maintained or accelerated

in some nations or blocs throughout the decade. In the EU, for instance, USDA (2011) projects biodiesel produc-tion will increase 22  percent and ethanol production will increase more than 40 percent by 2020 in response to bio-fuels blending mandates. Further, USDA projects Brazilian ethanol production will increase 45 percent by 2020, largely because of stronger expected export demand. Ethanol and biodiesel production increases from traditional feedstocks are also projected in Canada and Argentina.

However, growth in the use of certain agricultural com-modities as biofuels feedstocks is expected to moderate in the next 10 years in some other nations. For example, USDA projects maize use for ethanol in the United States will be 128  million tonne in 2011/12, but will grow only gradually (1  percent per year) to 140  million tonne by 2020/21 (USDA, 2011). There are two major reasons for the expected slower rate of growth in the use of agricultural feedstocks for biofuels in the United States and some other nations. First, government policies in several nations place restrictions on the amount of agricultural commodities that may be used for biofuels. For example, the United States’ RFS caps the amount of maize starch ethanol that can qualify for the mandate at a maximum of 57 billion litres (15  billion gallons) per year beginning in 2015. Similarly, China recently imposed regulations to limit grain ethanol production to current levels, effectively restricting any further growth in grain use for ethanol (USDA, 2011). The second reason for moderation in the growth in the use of agricultural commodities for biofuels is the expectation that future growth in biofuels production will primarily come from new feedstocks that currently have no or limited appli-cation in the animal feed market, such as perennial grasses (switch grass, miscanthus), agricultural residues (maize

FIGURE 5Global grain supply in relation to grain use for ethanol

and animal feed co-product production

Source: USDA data; F.O. Licht, 2011

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An outlook on world biofuel production and its implications for the animal feed industry 11

stalks, wheat straw), algae, jatropha, pennycress, municipal solid waste, forestry residues and other materials.

KNOWLEDGE GAPS AND FUTURE RESEARCH NEEDSWhile animal feed co-products from biofuels production have played an important role in the global livestock and poultry industries for many years, several critical knowl-edge and information gaps remain. First, as highlighted by Taheripour, Hertel and Tyner (2010b), many studies examin-ing the impact of biofuels demand on commodity prices and livestock and poultry markets do not properly account for the sustained price discount of co-product feeds versus traditional feedstuffs. There appears to be a general lack of understanding of how pricing trends and fluctuations affect co-product feeding decisions and dietary inclusion levels. The dynamic pricing relationship among animal feed co-products from biofuels processes and traditional feedstuffs, and the impacts of pricing relationships on substitution rates, is an area for further future research.

Additionally, understanding of the impact of biofuel feed co-products on livestock and poultry markets has been greatly hindered by a lack of public data and information on co-product production volumes by type and geography. Government agencies that track and publish public market data for traditional feedstuffs and commodities generally do not provide adequate coverage of co-product feed pro-duction volumes, types, etc. This is a significant information gap that, if filled, would enhance the collective understand-ing of co-product animal feed markets.

Finally, little is known about the effect of maize oil extraction on feeding and pricing of DDGS. This again is an area for future research.

CONCLUSIONSRecent years have seen a tremendous increase in the pro-duction of biofuels from agricultural commodities. Growth in biofuel production has been accompanied by increased output of animal feed co-products from common biofuel processes. Globally, these feed co-products are growing in volume and importance. While the increased use of agri-cultural commodities for biofuels is generally expected to contribute to slightly higher input costs for certain livestock and poultry feeds, the impacts are expected to be modest and can be mitigated in part by increased substitution of co-products for traditional feedstuffs. Increased agricultural productivity has allowed the global supply of crops available for non-biofuel uses to continue to grow over the long term. Growth in the use of agricultural commodities for biofuels is expected to continue through to 2020, but growth rates will slow in key producing countries as government-imposed limits on grain use for biofuels are reached and new non-agricultural feedstocks are commercialized.

ACKNOWLEDGEMENTSThe authors would to acknowledge Claus Keller, com-modity analyst at F.O. Licht, for providing data on global feedstock use for ethanol and biodiesel; and Ann Lewis, analyst for the Renewable Fuels Association, for assistance in researching and preparing this article.

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