Postharvest quality issues and breeding

Wageningen UR - Food&Biobased Research Jan Verschoor

Intro Jan Verschoor

Background: Food Technologist by education (specialty Toxicology)

20 year research experience in PH-Technology at Wageningen UR

● Optimal storage conditions F&V

● Disorder studies: Pome and soft fruits, vegetables

● Fresh product physiology: Fruits, vegetables, ornamentals

● Development of Dynamic Controlled Atmosphere Systems

● Postharvest technology evaluation/development: (ethylene) sensors ,

CO2-and ethylene scrubbers, LED-lighting, 1-MCP, coatings etc.

● Non-chemical Postharvest insect control (CATT)

● Post-harvest training and consultancy

Wageningen UR Campus

Food & Biobased Research

Agrotechnology & Food Sciences

Agrotechnology & Food Sciences

Group

Food & Biobased Research

Agrotechnology & Food Sciences

Agrotechnology & Food Sciences

Group

Structure Wageningen UR

Wageningen International

IMARES

Wageningen Business School

RIKILT

Food & Biobased Research

Livestock Research

Central

Veterinary Institute

Alterra LEI Centre for

Development Innovation

Plant Research International

Applied Plant

Research

Agrotechnology & Food Sciences

Group

Agrotechnology & Food Science

Animal Sciences Environmental Sciences

Social Sciences Plant Sciences

Animal Sciences Group

Environmental Sciences Group

Social Sciences Group

Plant Sciences Group

Supervisory Board

Executive Board

Concern Staff Facilities & Services

Specialized Research Institutes (CRO’s)

Wageningen University

…To explore the potential of nature,

to improve the quality of life…

Presentation overview

• Introduction Postharvest quality

• Postharvest quality issues

• Postharvest quality issues control

Introduction Postharvest Quality

• Depends on (consumer) expectance

• Is cumulative effect of – Initial quality

• Genotype

• Growing conditions

– Postharvest conditions

• Never improves over time

Introduction Postharvest Quality

• ~1/3 of produced products is lost!

– Mechanical, physiological, microbiological reasons

– Overproduction, no buyers, loss of value (feed, processing)

• All inputs (energy, water, nutrients, land use) also lost

• From a nutritional point of view current postharvest crop losses can feed over 2 billion people

The postharvest chain is not optimal

Enormous effort is put into optimizing breeding and cultivation, to increase production, …

• Breeding (pest resistance, production, ..) • Education (agriculture, horticulture) • Advisory networks for growers • 5% production increase is an major challenge

But …. there is a lot to gain by optimizing postharvest handling and distribution

• 5% less postharvest spoilage is a relatively easy goal

• 5% more profit in postharvest is a relatively easy goal

Introduction Postharvest Quality

Qu

alit

y

Phenotype

Genotype

Growing conditions Postharvest

handling

Postharvest quality issues

• Physiological

• Caused by storage conditioning /duration

• Microbial (in fruits mainly fungal)

• Mechanical

• Other

Postharvest quality issue: Bitter pit

Postharvest quality issue: scald

Quality issues: Chilling injury

Postharvest quality issue: Soft scald

Quality issue: senescent breakdown

Postharvest quality issue: Water core

Postharvest quality issue: Water core

Quality issue: Skinspots (Elstar)

Postharvest quality issues: shrivelling

Quality issue: external CO2 injury

Quality issues: internal CO2-injury

Quality issue: Low oxygen injury

Quality issue: freezing injury

Postharvest quality issue: Lenticelspot

Postharvest quality issues control

Storage quality starts with quality at harvest

“Initial quality” • Cultivar!!!!!!

• Harvest maturity

• Experiences of previous seasons

• Other – Soil type, altitude

– Crop load

– Fruit size

– Batch variation

Harvest date

Methods for apples/pears

– Days after full bloom

– Growing-degree hours (model)

– Starch index (lugol staining)

– Sugar content (total soluble solids (ºBrix, refractometer)

– Firmness (penetrometer)

– Streif index (= Firmness / (Suger content x starch index)

– NIR

– Genetic markers

Importance of harvest window

Harvest window

Greasiness Jonagold

Gre

asin

ess

(ra

nge

)

Number of days in 20 oC

relation fruit weight and weight loss

0.100

0.200

0.300

0.400

0.500

0.600

0.700

0 100 200 300 400 500 600

Fruit weight(g)

Weig

ht

los

s (

g/(

kg

*h)

Harvest 1

Harvest 2

Harvest 3

Effect harvest date on weight loss pears

Consequenses of harvesting later

+ more kg, increased fruit size (can also be negative)

+ higher sugar content/less acid/more aroma

+ more (red) blush colour

+ less sensitive for scald, bitter pit

+ less weight loss

- Less green ground colour, more yellowing

- Lower firmness

- Shorter storability, shelf life

- More sensitive for chilling injury,internal browning, core flush, fungal decay, greasiness

Optimal quality and storage conditions

T. laag T hoog

CO2 hoog CO2 laag

O2 laag O2 hoog

setpoint

Ripening, senescence disorder

Fruit storage and ethylene removal 33

Principle Dynamic CA (DCA):

Interactive Storage Conditioning

Relative respiration

0 % O2 21

ULO

Safety margin to account for biological variation

Fruit storage and ethylene removal 34

Principle Dynamic CA (DCA):

Interactive Storage Conditioning

Reduction of respiration compared to ULO

Relative respiration

0 % O2 21

DCA

• Ethanol (fermentation metabolite) • Respiratory Quotient (CO2 production/O2 consumption) • Fα (Chlorophyll fluorescence)

Used markers to find optimum:

DCA effect on scald

sensitive Italian Granny S. after 8 months + shelflife

Prevention of scald development – good alternative for chemical treatment DPA

DCA ULO

~0,4 % O2 1.2% O2

Postharvest quality issues control

0

0.1

0.2

0.3

0.4

0.5

0.6

2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8

Fra

cti

n o

f fr

uit

s

Firmness class (per 0.5 kg)

ULO, Smartfresh and DCA firmness distribution Elstar apples after 8 months

storage + 1 week shelflife

Postharvest quality issues control

0

0.1

0.2

0.3

0.4

0.5

0.6

2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8

Fra

cti

n o

f fr

uit

s

Firmness class (per 0.5 kg)

ULO, Smartfresh and DCA firmness distribution Elstar apples after 8 months

storage + 1 week shelflife

Postharvest quality issues control

0

0.1

0.2

0.3

0.4

0.5

0.6

2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8

Fra

cti

n o

f fr

uit

s

Firmness class (per 0.5 kg)

ULO, Smartfresh and DCA firmness distribution Elstar apples after 8 months

storage + 1 week shelflife

Postharvest quality issues control

Lenticelspot and water loss (Elstar apples)

Orchard

Ha

rves

t

Percentage lenticelspot:

Weight loss

normal

(2.6-3%)

Weight loss

low

(1.5-1.8%)

A 1e 0 13.2

A 2e 5.2 16.7

B 1e 0 37.1

B 2e 25.3 63.6

Influence waiting period on brown heart teler 1, 1997-1998

0

20

40

60

80

100

0 2 4 6 8 10 12 14 16 18 20 22dagen wachtperiode

ho

l e

n b

ruin

(%

)

teler 2, 1997-1998

0

20

40

60

80

100

0 2 4 6 8 10 12 14 16 18 20 22dagen wachtperiode

ho

l en

bru

in (

%)

Optimal storage conditions

Tools to prevent/limit disorders • Identify risk batches at harvest • Regular quality checks during storage • Monitoring water loss during storage • Optimize storage conditions (research based) Some interventions (depending on product & disorder) • Cooling down in steps • Waiting period before CA • Adjusting optimal T/CO2/O2/water loss • Ethylene control

• Cultivar selection

Breeding selection issues

• Production factors – many

• Consumer and market appeal –Do we know?

• Postharvest factors

Impossible????? Hopeless???

Moneymaker #1 USA apples

Breeding succes improvement

Improvement of prediction of postharvest behaviour will result in less very costly failures

More attention for development and standardization of Postharvest testing protocols is required

Breeding succes improvement

Improvement of prediction of postharvest behaviour will result in less very costly failures

More attention for development and standardization of Postharvest testing protocols is required

Thanks for your attention