POSTHARVEST HANDLING
OF BRAMBLES
PENELOPE PERKINS-VEAZIE
NCSU
KANNAPOLIS NC
penelope_perkins@ncsu.edu
DIFFERENCES FROM OTHER
CROPS
•
•
•
•
MUST BE FULLY RIPE
MUST PICK INTO FINAL CONTAINER
NO WASHING
RAPID COOLING AND COLD CHAIN
CRITICAL
• NO MECHANICAL SORTING
• CONSUMERS EAT WITHOUT
WASHING
SYSTEMS
1. ON FARM/FARMERS MARKET
-U Pick
-Pick into larger containers (quart)
-Softer varieties can be used
2. SHIPPING
-Pick into small containers (pint)
-Cold chain management is critical
-Use only firm varieties
STEPS FOR QUALITY
PREHARVEST
• VARIETY SELECTION
• CONTAINER
• HARVEST/HANDLING
SYSTEM
FIRST STEP IN POSTHARVEST LIFE:
VARIETY SELECTION
FIRMNESS: GET IT OFF THE PLANT WITHOUT
LEAKING
SHAPE AND SIZE: ROUND/LONG, LARGE /SMALL
(WHAT FITS YOUR PACKAGE AND MARKET?)
SHELF LIFE: DECAY RESISTANCE, TRANSPORT
RESISTANCE
OTHER DEFECTS: SUNBURN, RED DRUPE
FIRMNESS (COMPRESSION)
LBS FIRMNESS FOR EACH
COMMODITY
6
5
FIRM
4
3
SOFT
2
1
0
BLUEBERRY STRAWBERRY BLACKBERRY RASPBERRY
FIRMER IS MORE RESISTANT TO BRUISE AND LEAK
SELECTIONS
NATIONAL SHIPPING
NAVAHO
NATCHEZ
APACHE
ARAPAHO
OUCHITA
CHESTER THORNLESS
NUMBER OF BERRIES PER PINT
40 NAVAHO
40 ARAPAHO
35 CHESTER
30 OUACHITA
25 APACHE
25 NATCHEZ
CONTAINERS
• PLASTIC CLAMSHELL
• ½ PINT, PINT, 12 AND 18 OZ
(NO MORE THAN 3 LAYERS)
• VENTED ON TOP AND SIDES
• UPICK/FARMERS: QUART
AND LARGER
CONTAINER
STACKABLE
2 LB BASKET FOR LOCAL ONLY
CLAMSHELL
WITH ROUND
HOLES
CLAMSHELL
WITH SLITS
MASTER FLATS
OR CARTONS
REINFORCED CORNERS
SIDES STACK VERTICALLY
FORCED AIR VENTS
HOLD 12 CLAMSHELLS
MASTER
WITH AIR
VENTS
TOP FLAT
GUARD
PICK FULL BLACK, FIRM
BE GENTLE!
KEEP FRUIT
SHADED
WHILE
PICKING
70F
80F
SHADED SIDE
N-S PLANTING
DON’T OVERFILL
MOLDS/FUNGAL
PICK EVERY 2-3 DAYS
TO AVOID OVERRIPE
AND DECAYED FRUIT
PICK OFF
OVERRIPE/DECAYED
FRUIT AND DISCARD
BOTRYTIS-GRAY MOLD
OTHERS: ANTHRACNOSE, RUST,
CLADISPORIUM, FUSARIUM, YEASTS
RUST
PREHARVEST
INJURY
POSTHARVEST
AVOID
THESE
FRUIT
WHEN
PICKING
HEAT/BRUISE
SUNBURN
RAIN DAMAGE
RED DRUPE
PACKING
SYSTEM 1
PICK INTO CLAMSHELL
PLACE CLAMSHELLS IN
TOMATO BOX
TRANSPORT TO SHED
CHECK/REPACK FRUIT IN
CLAMSHELLS
PLACE IN MASTERS AND
PUT IN COLD ROOM
PACKING SYSTEM 2
FIELD ONLY
PICK INTO CLAMSHELLS
BRING TO FIELD PACKHOUSE
SORT FOR LEAK, DAMAGE
PLACE INTO REEFER
PACKING GUIDE CHART
SANITATION: CONSUMERS DON’T
ALWAYS WASH FRUIT!
PROVIDE WASH STATION AS WELL
AS TOILET FACILITIES
STEPS FOR QUALITY
POSTHARVEST
• COOLING
• CA/MA
• TRANSIT
COOLING BLACKBERRIES
• DELAYS DECAY
• REDUCES RESPIRATION/WEIGHT LOSS
• CAN CAUSE CONDENSATE IF CHANGES
IN TEMPERATURE OCCUR
COOLING IS THE MOST EFFECTIVE
PRETREATMENT FOR BLACKBERRY
SHELF LIFE !
DISEASES
• RHIZOPUS (LEAKY ROT)
>41 F
• BOTRYTIS (GRAY MOLD)
>32 F
• ANTHRACNOSE >41 F
TEMPERATURE INCREASE
RESPIRATION INCREASES
WEIGHT LOSS INCREASES
DECAY INCREASES
14
12
10
8
6
4
2
0
RESPIRATION RATE
DAYS LIFE
32
41
68
CONDENSATION
• WARM AIR HOLDS MORE MOISTURE
THAN COLD AIR
• AS AIR COOLS, WATER FALLS OUT
ONTO COLDEST SURFACE
• PLASTIC COOLS FASTER THAN FRUIT
COOLING
• ROOM/ REEFER COOLING
• FORCED AIR COOLING
http://www.storeitcold.com/
ROOM COOLING:
ALLOW AIR MOVEMENT BETWEEN
BOXES AND FLATS
VENTS IN MASTER FOR AIR
FLOW WITHIN CARTON
COLD ROOMS
• RAILWAY CARS + ELECTRIC MOTOR +
DIESEL GENERATOR
• SELF-CONSTRUCTED
• USED RESTAURANT COLD/FREEZER
ROOMS
• OFTEN FA IS INSIDE A LARGER COLD
ROOM
• CONVERT AC UNIT TO COOLING (COOLBOT)
http://www.storeitcold.com/
COOLING ROOM DIAGRAM
STEEL OR AL FRAME
SUPPORTS,
2 M CENTERS
10 CM
EVAPORATOR
UNIT
METAL
CLADDING,
CAULKED
POLY U
FOAM
DOOR
7.5 CM
REINFORCED CONCRETE FLOOR
5 CM
CONCRETE SUB FLOOR
AL CHANNEL,
SLIDING DOOR TRACK,
FOAM, RUBBER SEAL
SOLID
RUBBER
LOWER SEAL
FORCED-AIR COOLING
FORCES COLD AIR THROUGH
DIRECTED PATHS IN BOXED FRUIT
• CAN BE FIELD PORTABLE
• ROOM PORTABLE
• BUILT-IN
CURTAIN
FA FANS
STORAGE AFTER COOLING
• KEEP NEAR 32 F
• KEEP RELATIVE HUMIDITY >90%
• HOLD NO MORE THAN 2 DAYS
EXTRA LABELING FOR CORRECT
TEMPERATURE
AVOIDING WEAK LINKS IN THE
COLD CHAIN
1. COOL AS QUICKLY AS POSSIBLEMAKE SEVERAL SMALL TRIPS
TO COOLER
2. KEEP PRODUCT COOLER IN
FIELD-USE SHADE, ADD MIST
SYSTEM (WHERE LOW
HUMIDITY)
3. PAY ATTENTION TO AIR FLOW,
STACKING, BOX VENTS
COLD CHAIN (CONT)
• LOAD INTO REFRIGERATED
TRANSIT AS QUICKLY AS POSSIBLE
• UNLOAD INTO REFRIGERATED
STORAGE QUICKLY
• MEASURE/MONITOR
TEMPERATURE AT EACH STEP
USING RECORDERS
MA OR CA STORAGE
• MUST BE HELD AT 0-5 C (32-41 F) TO
BE EFFECTIVE
• BLACKBERRIES NEED 5-10% OXYGEN
AND CAN TOLERATE 10-20% CARBON
DIOXIDE
MA OR CA STORAGE
• USED DURING TRANSPORT (3-5
DAYS)
• EXCELLENT CONTROL OF GRAY
MOLD
• KEEPS FRUIT IN ‘SUSPENDED
ANIMATION’
PALETTE MA USING FILM OVERLAY WITH
INJECTED CO2
MA VERSUS TEMPERATURE
POSTHARVEST LIFE OF BLACKBERRIES
(DAYS)
STORAGE TEMPERATURE
68 F
41 F
32 F
AIR
1
3
7
MA
2
4
10
LOW TEMPERATURE IS MORE EFFECTIVE THAN MA
SUMMARY
• CONTROL HARVEST
OPERATION
• REDUCE FIELD HEAT LOAD
• KEEP FRUIT COOL DURING
STORAGE AND TRANSIT
• USE MA ONLY IF A PREMIUM
PRICE
SOURCES OF INFORMATION
• BRAMBLE PRODUCTION GUIDE
(CORNELL UNIVERSITY)
• SMALL SCALE POSTHARVEST
HANDLING PRACTICES (UC-DAVIS)
• POSTHARVEST TECHNOLOGY OF
HORTICULTURAL CROPS (UCDAVIS)
SOURCES-WEB SITES
• NORTH CAROLINE STATE
http://www.bae.ncsu.edu/programs/exte
nsion/publicat/postharv/
• UNIV CALIFORNIA-DAVIS AND UCKEARNEYSVILLE
http://postharvest.ucdavis.edu/
• USDA HANDBOOK 66
http://www.ba.ars.usda.gov/hb66/contents.
html