ComiceComice Bosc d’Anjou

ForelleStarkrimson Bartlett

European PearsEuropean Pears

European Pears are Harvested Unripe, but Mature

Firmness (lbs.-force) Soluble Solids (%)Bartlett 19-20 < 10

20-21 1020.5-21.5 11

21-22 12D’Anjou 10-15Comice 9-13Bosc 11-16

Harvest by handinto large soft-sidedpicking bags.

Empty into field bins.

Harvest by handinto large soft-sidedpicking bags.

Empty into field bins.

Dumping fruit from field bin to packingline

• Combination wet/drydump

• Dry dump

Dumping fruit from field bin to packingline

• Combination wet/drydump

• Dry dump

Immersion dump from field bin to packingline

• bin pulled under water and fruit float out• need floatation salts• gentle

Immersion dump from field bin to packingline

• bin pulled under water and fruit float out• need floatation salts• gentle

Sorting Pears into Two GradesCenter Lane for Canning and Juice

Sorting Pears into Two GradesCenter Lane for Canning and Juice

Weight Sizer and Place Pack OperationWeight Sizer and Place Pack Operation

Place Pack OperationEach fruit wrapped in tissue and

placed in box in a pattern

Place Pack OperationEach fruit wrapped in tissue and

placed in box in a pattern

Volume Fill Volume Fill

Tray-Pack BoxCan Also Display in Box

Tray-Pack BoxCan Also Display in Box

13

Consumer Bags

Clamshell Container for Pears

Packaging that Senses Pear Ripeness

Hammock Pack

Factors Affecting Pear QualityFactors Affecting Pear Quality

• Harvest maturity• Delays before cold storage• Speed of cooling• Storage temperature• Relative humidity in storage• Length of storage• Storage atmosphere - O2, CO2, ethylene

• Harvest maturity• Delays before cold storage• Speed of cooling• Storage temperature• Relative humidity in storage• Length of storage• Storage atmosphere - O2, CO2, ethylene

Cold Storage at 1°C (33 °F)

DAYS DELAY

0 1 2

3 4 5

Effect of Delays in Cold Storageon Pear Quality

Effect of Delays in Cold Storageon Pear Quality

Lake County 8/2310 weeks Storage

-1 -0.5 0.5 1 2°C

Effect of Storage Temperature on Pear Quality

Effect of Storage Temperature on Pear Quality

Harvested 8/2/2001Stored 3 months

Harvested 8/2/2001Stored 3 months2°C (36 F) -1°C (30 F)

0 ppm 0 ppm

1 ppm

Effects of Temperature and Ethylene on Bartlett Pears

Effects of Temperature and Ethylene on Bartlett Pears

1 ppm

Storage ScaldStorage Scald

Methods of Control• Ethoxyquin• CA Storage

Methods of Control• Ethoxyquin• CA Storage

Botrytis Rot

Benefits of CA StorageBenefits of CA Storage

• Delays fruit ripening and senescence¨ softening¨ yellowing¨ scald development

• Extends storage life

• Delays fruit ripening and senescence¨ softening¨ yellowing¨ scald development

• Extends storage life

Benefits of Controlled Atmosphere Storage

Benefits of Controlled Atmosphere Storage

6 months in Air 6 months in 2% O2

Ripening Pears are Preferred 3 to 1 over Un-Ripe Pears

Bartlett PearsHarvested and Immediately Ripened

8d air 20°C (68°F)

1d C2H4

7d air 20°C (68°F)

Firm

ness

(lb

s)

0

4

8

12

16

20

Firm

ness

(N

)

0

20

40

60

80

days vs at harv days vs S harv+100ppm

Col 16 vs Col 17

Days @ 68°F (20°C)

0 1 2 3 4 5 6 7

Eth

ylen

e pr

oduc

tion

(µl•

kg-1

h-1)

0

20

40

Air

100 ppm ethylene 24 hr

Why do Pears Need Conditioning?

Why do Pears Need Conditioning?

• Pears have insufficient capacity to produce ethylene at harvest– lack of precursor, ACC

• ACC accumulates during cold storage• Ethylene treatment stimulates

production of ACC and ethylene

• Pears have insufficient capacity to produce ethylene at harvest– lack of precursor, ACC

• ACC accumulates during cold storage• Ethylene treatment stimulates

production of ACC and ethylene

Ethylene Production during RipeningEthylene Production during Ripening

• More uniform softening• Enhanced production of flavor and

aroma volatiles• Improved texture of fruit

– buttery, not gritty– juicy

• More uniform softening• Enhanced production of flavor and

aroma volatiles• Improved texture of fruit

– buttery, not gritty– juicy

Conditioning Pears for Ripening

Comice Bartlett Bosc Anjou

Cold Storage @ 30-32°F 4 2-3 2 8 wks

Cold Storage @ 40-50°F 2-3 1 1 3-6wks

100ppm Ethylene @ 68°F 3 1-2 1 3 days

100ppm Ethylene @ 45-50º ? 2-3 ? ? days

Cold storage requirements may be longer when fruit are stored in CA

APPLES

Goal

Maximize• Storage life• Blush• Sensory quality

– Crispness– Flavor– Sweetness

• Size

Minimize• Softening and mealiness• Disorders

– Bitter pit– Scald– Internal browning– Checking

Indicators of Harvest Maturity

• # Days from full bloom• Time/temp (heat units) from anthesis• Days from harvest to onset of ethylene

production• Ground color• Soluble solids content• Flesh firmness and SSC• Starch disappearance pattern• Internal ethylene concentration• Changes in firmness or starch content

Starch Content is a Common Indicator of Harvest Maturity

Hand Harvest into Small Padded Picking BagsHighly Susceptible to Bruising

Carefully transferto field bin!!

Avoid bruising!

Apple Bruising Incidence during Harvest and Postharvest Handling

Bruises/Fruit

% Bruised Fruit

Picking/dumping 2.6 18.8

Hauling 2.2 15.9

Packing Line 5.5 61.6

Transportation 0.5 3.7

Total 13.8 100

Drenching bins ofapples prior tostorage

• Diphenylamine -antioxidant to control scald• Fungicide• Calcium to control bitter pit

Immersion of bins

Apples naturally float

• Very gentle!!

Optical Sorting for Color, Size and DefectsOptical Sorting for Color, Size and Defects

Washing of Apples with Brushes and DetergentWashing of Apples with Brushes and Detergent

Wax ApplicationWax Application

Hand Sorting Remains NecessaryEven with Electronic Sorting

Hand Sorting Remains NecessaryEven with Electronic Sorting

Tray Packing after Sizing

Controlled Atmosphere StorageControlled Atmosphere Storage

• Store 1.5 to 12+ months• 0.7 to 3% oxygen• 0.5 to 4% carbon dioxide• Maintains firmness, ground color and

acidity by reducing respiration and the effects of ethylene

• Reduces storage scald and bitter pit• May induce disorders such as internal

browning

• Store 1.5 to 12+ months• 0.7 to 3% oxygen• 0.5 to 4% carbon dioxide• Maintains firmness, ground color and

acidity by reducing respiration and the effects of ethylene

• Reduces storage scald and bitter pit• May induce disorders such as internal

browning

Effect of Carbon Dioxide Concentration on Internal Browning

0.4% CO2

2% O2

1.5% CO2

2% O2

3% CO2

2% O2

Air

Fuji ApplesHarvest 10/17/92

4 months @ 0.5ºC

Penicillium expansum on Apple• Wound pathogen• Controlled by Low-Temperature Storage

Botrytis Rot on Apple

Side, stem or blossom infectionsGrowth is reduced at 0°C (32°F)

Storage Scald on Granny Smith Apples• Oxidative damage to upper cell layers• Cultivars vary in susceptibility• Hot and dry climates increase susceptibility• Diphenylamine used for control• SmartFresh (1-MCP) also reduces scald

• Low calcium/high N2

• High vigor trees• Young trees

• Large fruit• Develops on the tree or during first 4 - 6 weeksof storage

An accumulation of sorbitol in the intercellular spaces

Mealiness

• Soft texture causing a dry feeling in the mouth during chewing– Low adhesion between cells– Retain strong cell walls

• Cells pull apart instead of breaking when you bite – no juicy sensation

• Cultivars vary in their susceptibility• Develops after extended cold storage

Use of SmartFresh on Apples1-methylcyclopropane

Use of SmartFresh on Apples1-methylcyclopropane

• Applied at harvest in storage room• Prevents/reduces the action of ethylene

on the apples• Use alone or together with CA• Maintains firmness and titratable acidity• No effect on starch conversion to sugars• Reduces storage scald and mealiness

• Applied at harvest in storage room• Prevents/reduces the action of ethylene

on the apples• Use alone or together with CA• Maintains firmness and titratable acidity• No effect on starch conversion to sugars• Reduces storage scald and mealiness

Initial Fruit Quality

Determines the Ripened Quality!!

Questions?