Phytosanitary Irradiation Quality Studies

Anuradha Prakash

Chapman University

•Dose response studies to determine tolerance of fruit to irradiation

•Comparison to conventional treatments

• Effect of commercial treatment and distribution

Protocol

Irradiated at 0 and 0.4 kGy at FTSI

Shipped to Chapman by refrigerated truck

Weight loss

Internal

disorder

development

Percentage

decay

Texture

Analyzed

using a

penetrometer

Sensory

Consumer testing with

untrained panels using

9 point hedonic scales

Quality tests performed at 1, 7, and 14 days following irradiation

Peaches shipped from GA/SC to FTSI

Chemical

pH, Titratable

Acidity, Brix

Peaches

Consumers preferred Irradiated Peaches

4

a b b b ba a a a aa a a a aa a a a a0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

OverallAppearance

Overall Flavor Overall Texture Overall Juiciness Overall Liking

Day 7 Titan Control

Day 7 Titan Irradiated

Day 13 Titan Control

Day 13 Titan Irradiated

b aa a0%

10%

20%

30%

40%

50%

60%

70%

Day 7 Day 13

Titan Control

Titan Irradiated

9 Point Hedonics

Preference

n=57

n=47

Titan - Blaze Prince

Ground shipment study: blueberries• Fresh Vaccinium ashei, Rabbiteye “Premier” blueberries harvested in

Georgia, June 2014

5

Retail display, ambient temperature

MeBr

15.56 °C and 32g/m3 for 3.5 hours

Forced air cooled to 1°C

Ground shipment to Gateway America, Gulfport, MS

Ground shipment to Chapman Univ, Orange, CA

Irradiation

Forced air cooled to 1°C

Ground shipment to Gateway America, Gulfport, MS

Gamma irradiation at 150 and 400 Gy

Ground shipment to Chapman Univ, Orange, CA

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

MeBr 150 Gy 400 Gy MeBr 150 Gy 400 Gy MeBr 150 Gy 400 Gy

Day 1 Day 3 Day 5

% D

amag

e

Retail display

Good Berries Decay Softness Physical Defects

MeBr 150 Gy 400 Gy

Day 8

Day 10

Day 12

California Retail Conditions

Strawberry Air Shipment study

Transported to Chapman University

Stored overnight at 1°C

Insulated for air shipment

1 day

Unwrapped, retail display, ambient

temperature, 4 days

MeBr15.56 °C and

32g/m3 for 3.5 hours, Raymond

Express

Forced air cooled to 1°C

Irradiation Forced air cooled to 1°C

Transported to Sterigenics,

400 Gy

ControlForced air

cooled to 1°C

Freshly harvested strawberries ❖ Marquee:

June 2014, Santa Maria

❖ Amado: October and November 2014, Oxnard

Packaging with astrofoil

Chapman University

-5

0

5

10

15

20

25

9am

10

am

11

am

12

pm

1p

m

2p

m

3p

m

4p

m

5p

m

11

pm

5am

11

am

5p

m

11

pm

5am

11

am

5p

m

11

pm

5am

11

am

5p

m

11

pm

5am

11

am

5p

m

11

pm

0 1 2 3 4

Air freight Control Air freight MeBr

Air freight Irradiated Refrigerated Control

Texture

0

50

100

150

200

250

Day 2 Day 4

Forc

e (

N)

Refrigerated Control Air freight contriol Air freight irradiated Air freight MeBr

Sensory

5.6

5.8

6

6.2

6.4

6.6

6.8

7

7.2

7.4

Appearance Flavor Texture Overall Liking

9-P

t. H

ed

on

ic S

cale

Marquee (trial 2) strawberries

Trial 4 Refrigerated control Trial 4 Air freight irardiated

Trial 4 Air freight MeBr Trial 4 Air freight control

0

5

10

15

20

25

30

35

40

45

Air Freight Control Air FreightIrradiation

Air Freight MethylBromide

% o

f D

amag

e

Marquee Strawberries Trial 1

0

10

20

30

40

50

60

70

80

90

Air Freight Control Air FreightIrradiation

Air Freight MethylBromide

% o

f D

amag

e

Amado Strawberries Trial 1

0

10

20

30

40

50

60

Air Freight Control Air FreightIrradiation

Air Freight MethylBromide

% o

f D

amag

e

Marquee Strawberries Trial 2

wet leaky

dry bruise

mold/decay

0

10

20

30

40

50

60

70

80

90

Air Freight Control Air FreightIrradiation

Air Freight MethylBromide

% o

f D

mag

e

Amado Strawberries Trial 2

wet leaky

dry bruise

mold/decay

Control MeBr Irradiation

Amado

Marquee

Day 4 ambient temperature display

Control 150 Gy

1000 Gy400 Gy

Seedless Kishu Mandarins

Control

150 Gy

1000 Gy

Chandler Pummelos

Future Studies

19

Peaches

Harvest Immature

Irradiate immediately

Quality, Sensory and shelf life testing

Store at ideal temperatures

Store at commercial and/or home refrigeration temperatures

Irradiate after delay

Quality, Sensory and shelf life testing

Harvest at more mature stage

Irradiate immediately

Quality, Sensory and shelf life testing

Considerations

• Harvest times• How many varieties?• Maturity at harvest• Other qualifiers-size, color• How is the fruit packed?• Where is the product exported to?• How long does it take?

• Shipping conditions

• Storage conditions• Storage life• How is quality measured?

Acknowledgments

• Heather Mcdonald• Karina Rodriguez• Akanksha Jain• Tamar Serapian• Dr. Jose de Jesus Ornelas Paz•

• USDA-APHIS• Titan Farms• Lane Southern Orchards• Georgia and South Carolina Peach Council• FTSI • Naturipe• Gateway America• Sterigenics