Funding: Partial support from National Science Foundation's ADVANCE IT Program under Award HRD-1007978. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.Partial support from Branch Banking and Trust Company’s CRA / Community Development Donation Fund.Partial support from Northeast SARE Professional Development Grant# ENE12-125Acknowledgements: Susan Slider, Brett Kenney, West Virginia University.

DRYING SURPLUS FRUIT – ADDING VALUE TO INCREASE FOOD SAFETY, YIELD, EFFICIENCY AND SUSTAINABILITY FOR WEST VIRGINIA FRUIT

OPERATIONSLitha Sivanandan1, Alexandra Smith2, Kaushlendra Singh2, Winifred W. McGee3, Brett Kenney2, Jacek Jaczynski2, Judy Matlick1, Brenda Porter1

1. Extension Service; West Virginia University, 2. Davis College of Agriculture, Natural Resources, and Design; West Virginia University, 3. Penn State Extension; Pennsylvania State University.

INTRODUCTION

EQUIPMENT/MATERIALS

METHODS

RESULTS/OUTCOMES

ABSTRACTWest Virginia fruit producers regularly face production and marketing risk, in that they are frequently unable to sell all the fruit grown. Since the cost of production remains the same, whether fruit is sold, left un-harvested, or harvested then discarded, it is important to convert the surplus into a valuable commodity, such as shelf-stable dried fruit. Fruit may then be sold direct to consumers, or whole-sale to value-added producers, generating revenues. WVU research indicates that pre-treatments such as fruit firming and/or osmotic dehydration (OD) drying are affordable options for small-scale producers. OD results in moisture loss and sugar solids gain, thus improving the overall quality and food safety of the dried fruit products. Spent osmotic solutions (SOS) can be converted into value-added bio-products using hydrothermal treatment, thereby eliminating regulatory treatment requirements for waste disposal.

Osmotic dehydration (OD): Fruit is placed in a hypertonic solution (juice concentrate/sugar) resulting in diffusion of water from the fruit with concurrent diffusion of the solutes from the solution. Vacuum impregnation (VI): Fruit is placed in a hypertonic solution with a decrease in external pressure for a certain amount of time; after which external pressure is raised back up to atmospheric pressure.Pulsed vacuum osmotic dehydration (PVOD): Fruit is placed in a hypertonic solution with a decrease in external pressure for a short time, followed by a relatively longer OD interval at atmospheric pressure.Fruit firming: Some fruits are susceptible to textural quality changes during ripening. Pectin methyl esterase (PME) removes methyl ester groups from the cell wall pectin constituents, which are accessible to depolymerization by polygalacturonase, reducing intercellular adhesiveness and tissue rigidity, and fruit firmness, making fruit-firming a necessary pretreatment. Research has shown that fruits treated with PME and calcium compound improves its firmness.Value-added bio-products using hydrothermal treatment: Hydrothermal carbonization (HTC) is defined as a mild form of pyrolysis using an aqueous feedstock. During HTC, biomass is treated in hot compressed water yielding three product forms: solid hydrochar, aqueous compounds, and gases. The hydrochar isolates carbon and serves as chemical adsorbate media for other environmental applications.

Materials:o 1500g of Sugar Solution (or juice concentrate) 675 grams Sugar+ 825 ml Distilled Water (45°Brix) 975 grams Sugar+ 525 ml Distilled Water (65°Brix)o 500grams of frozen, scarified berries

Equipment:o Vacuum Chambero Compressed Air/Vacuum Pumpo Refractometer @$1,400(to measure

sugar in °Brix)o Steam jacketed mixing with agitator

($200)o Conventional food dehydrator ($100)o Water activity meter @$2,400 (to

measure water activity)

Fruit drying research and its industrial applications were disseminated through a series of Extension hands-on workshops (2011-2014) for educators, agricultural service providers, entrepreneurs, and prospective entrepreneurs. The resulting 6-hour intensive hands-on training workshops focused on various processes and equipment needed for increased fruit food safety, overall quality, yield, process efficiency, risks management, target market identification, and utilization of waste for bio-product applications. OD: Scarified, frozen blueberries were placed in sugar syrup concentrations of 65°Brix with a fruit to syrup ratio of 1:3 g/g. Fruit and syrup were heated at 50°C for 4 hours with occasional stirring. Weight of fruit was taken before and after processing for calculating yield. Conventional dehydration was used after osmotic dehydration at 135°F for 6.5 hours. Sunflower oil was applied to prevent stickiness and to provide a glossy appearance. Fruit-Firming: PME and calcium chloride was dissolved in water at 105°F. One pound of frozen strawberries was heated at 105°F in the above solution for two hours. The solution was drained and fruit was processed as stated above in OD section; drying time might be longer than blueberries. SOS: Fruit leather preparation, re-concentrating and re-using the syrup etc. are food product development options trained during the Extension workshops.

Conventional Dehydration-

135°F, 6.5 hours

Osmotic Dehydration Chamber

1:3g/g Fruitto SolutionShake

r Plate

Incubator

Schematic of osmotic dehydration apparatus.

Air Tank

Vacuum PumpVacuum

Chamber

Osmotic Dehydration Chamber1:3g/g

Fruit to Solution

Schematic of the Pulsed Vacuum Osmotic Dehydration

Apparatus.

36.0

38.0

40.0

42.0

44.0

46.0

48.0

50.0

41.1

49.0

Effect of Solution Concentration on Percent Yield Af-ter Conventional Drying

45 65Solution Concentration in °Brix

Perc

ent Y

ield

41

42

43

44

45

46

47

43.3

46.5

Effect of OD Temperature on Percent Yield After Conventional Drying

25 50Temperature in °C

Perc

ent Y

ield

40.0

42.0

44.0

46.0

48.0

50.0

42.7

44.1

48.0

Effect of OD Time on Percent Yield After Conven-tional Drying

180 240 300OD Time in Minutes

Perc

ent Y

ield

0.62

0.64

0.66

0.68

0.7

0.72

0.74

0.76

0.7398

0.7003

0.6602

0.7171

Effect of Solution Concentration and Temperature on Final Water Activity

45°Brix/25°C 45°Brix/50°C 65°Brix/25°C 65°Brix/50°CSolution Concentration*Temperature

Wat

er A

ctiv

ity

Workshops: Hands-on training combined with risk management education, food safety measures, and sustainability has been an attractive package for participants. Decreased waste, inexpensive costs, high yields (=$$), and shelf-stable products were appealing for entrepreneurs. 100% of the participants wanted to learn more about application of these techniques and were willing to attend another workshop however limited resources restrict us from providing these workshops and workshops for specific product (fruit) for each region.

HTC: Direct benefits for producing high functionality hydrochar were discussed. Additionally, indirect benefit for saving millions of gallons of fresh water needed to reduce biochemical oxygen demand, pH, and total soluble solids to meet regulatory standards, and capturing SOS-carbon, reducing green house gas emission in light of current federal and state regulations.