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  • Trevor SuslowQuality &

    Microbial Safety

    Michael ReidCut Flowers & Potted Plants

    Elizabeth MitchamMA & IPM Research

    Adel KaderFruit & Nut

    Quality

    Linda HarrisFood Safety

    POSTHARVEST SPECIALISTSPOSTHARVEST SPECIALISTS

    http://http://postharvest.ucdavis.edupostharvest.ucdavis.edu

    Jim Thompson, Faculty Director

    Cooling, Transport, Fumigation

    Carlos Crisosto

    Stone Fruits

    Roberta CookMarketing & Economics

    Marita Cantwell

    Vegetables & Fresh-Cut

    Christine Bruhn

    Consumer Issues

    Diane BarrettProcessing &

    Quality

    Mary Lu ArpaiaSubtropical

    Fruits

    Jim GornyExecutive DirectorFresh-cut, Food

    Safety, Regulatory

  • http://postharvest.ucdavis.edu

    WebinarsMinimal costsTimeCurrent topics

  • Fresh Produce Executive ForumFresh Produce Executive Forum WebinarWebinar SeriesSeries

    Jim Gorny, Trevor Suslow, initiated a Microbial Food Safety Series Nov 20, 2008: Fresh Produce Microbial Pathogen Testing:

    Program Components & Considerations Jan 12, 2009: Update on Irradiation

    Fresh-cut Products Series Target retailers and food service operators Critically examine shelf-life and quality Convince the buyers

    http://postharvest.ucdavis.edu/Announce/executive-series.html

  • http://postharvest.ucdavis.edu

    Produce Facts Harvest indices Quality indices Temperature and RH Freezing point/damage Respiration rates Ethylene production Effects of ethylene Effects of modified

    atmospheres Physiological disorders Postharvest diseases Mechanical injury PHOTOS

    140140FruitsFruitsVegetablesVegetablesFlowersFlowers

  • Postharvest Handling Challenges: Fresh-cut Veggie Tray

    Marita Cantwell, UC Davismicantwell@ucdavis.edu

    http://postharvest.ucdavis.edu

    Broccoli florets, Sugar snap peas, Celery sticks, Baby carrots, and Grape tomatoes

  • "Fresh-cut produce" is defined as any fresh fruit or vegetable or any combination thereof that has been physically altered from its original form, but remains in a fresh state. Regardless of commodity, it has been trimmed, peeled, washed and cut into 100% usable product that is subsequently bagged or prepackaged to offer consumers high nutrition, convenience and value while still maintaining freshness.

    Fresh-cut Produce

    Minimally Processed Lightly Processed Partially Processed Pre-prepared Fresh Processed Pre-cut Value-added

  • ProductsPotential post-

    cutting storage life at 2-5C (36-41F)

    VEGETABLESVEGETABLES DaysBaby carrots, peeled onions, peeled garlic >21Lettuce salads, lettuce separated leaves, lettuce mixes, spinach leaves, peeled potatoes

    14-18

    Broccoli & cauliflower florets, shredded cabbage, lettuce and broccoli, celery & carrot sticks

    10-14

    Pepper and tomato dices, cucumber slices, squash slices, mushroom slices, jicama sticks

    4-9

    FRUITSFRUITSApple wedges, pineapple chunks, pomegranate arils, kiwi slices

    10-14

    Strawberry slices, melon & mango cubes, citrus segments, peach & pear wedges, grape berries

    2-9

  • Vegetable trays- want 18 day shelf-life

    Products in tray and compatibility issues- raw material sourcing and handling before prepare - shelf-life of individual products in tray varies- temperature; 5C too low for grape tomatoes- modified atmospheresnot good for all products in tray

    Postharvest compatibilityTemperatureRelative humidityEthyleneOdors

    Postharvest compatibility Fresh-cutTemperatureModified Atmospheres

  • A. Quality EvaluationsDAYS 0, 6, 9, 12, 15, 18, 21DAYS 0, 6, 9, 12, 15, 18, 21 Overall Visual Quality ( 9-1) Discoloration (scored 1-5) Decay/Mold (Scored 1-5) Aroma typical (5 to 1) Off Odor (Scored 1-5) Off Flavor (Scored 1-5)

    B. CompositionDAYS 0, 6, 12, 18DAYS 0, 6, 12, 18 Sugar (mg/g FW; spectrophotometry; all vegetables) Vitamin C (mg/100g FW; HPLC tomato, broccoli, carrot) Ammonia (g/g FW; HPLC broccoli, snap peas) Acetaldehyde (nL/g FW; GC, all vegetables) Ethanol (nL/g FW; GC, all vegetables)

    C. Color data (Test 2)DAYS 0, 6, 12, 18DAYS 0, 6, 12, 18 L*a*b* color values, chroma, hue

    D. Respiration rates

    Atmospheres at 5CA = 3%O2 + 7%CO2B= 3%O2 + 12%CO2C= 3%O2 + 18%CO2D= 10%O2 +12%CO2E = Air (21% O2)

    Vegetable Party Trays

  • Grape tomatoes & postharvest handing

    High flavor quality, high market demand Common component of vegetable trays Susceptible to water loss Temperature recommendations?

    Produce Facts: Not below 10C Reality 5C for 3 weeks

  • 18 days at 5C (41F)

    A B C D E 3+7 3+12 3+18 10+12 Air

    Good quality, near ripe grape tomatoes will tolerate 5C for about 18 days

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    A. Visual Quality B. Weight Loss

    C. Firmness D. Red color

    LSD.05

    Grape Tomatoes (cv Amsterdam) stored in consumer packaging and evaluated at 4 storage temperatures. Cantwell, unpublished, 2004.

  • Initial + 5d 20C

    20d 5C + 5d 20C

    Grape tomatoes show typical chilling symptoms when transferredGrape tomatoes show typical chilling symptoms when transferred

    Cantwell and Ara, 2006

  • Grape Tomato Quality Changes Test#1 and #2

    Considerable variability in ripeness and quality Main defects are increased dehydration

    (sunken areas, shrivel) and decay Not much difference in quality changes among

    the 5 atmospheres By 15 days, slight changes in aroma, off-odor

    and off-flavors

    Raw material quality is key

    Variations inripeness andcondition whenreceived

  • A. Quality EvaluationsDAYS 0, 6, 9, 12, 15, 18, 21DAYS 0, 6, 9, 12, 15, 18, 21 Overall Visual Quality ( 9-1) Discoloration (scored 1-5) Decay/Mold (Scored 1-5) Aroma typical (5 to 1) Off Odor (Scored 1-5) Off Flavor (Scored 1-5)

    B. CompositionDAYS 0, 6, 12, 18DAYS 0, 6, 12, 18 Sugar (mg/g FW; spectrophotometry; all vegetables) Vitamin C (mg/100g FW; HPLC tomato, broccoli, carrot) Ammonia (g/g FW; HPLC broccoli, snap peas) Acetaldehyde (nL/g FW; GC, all vegetables) Ethanol (nL/g FW; GC, all vegetables)

    C. Color data (Test 2)DAYS 0, 6, 12, 18DAYS 0, 6, 12, 18 L*a*b* color values, chroma, hue

    D. Respiration rates

    Atmospheres at 5CA = 3%O2 + 7%CO2B= 3%O2 + 12%CO2C= 3%O2 + 18%CO2D= 10%O2 +12%CO2E = Air (21% O2)

    Vegetable Party Trays

  • 18 days at 5C (41F)

    A B C D E 3+7 3+12 3+18 10+12 Air

    BENEFICIALBENEFICIAL

  • 18 days at 5C (41F)

    A B C D E 3+7 3+12 3+18 10+12 Air

    DAMAGINGDAMAGING

  • Reduce shelf-life expectations Products incompatible 18D too long; 12D maximum

    Raw material quality critical Sourcing tomatoes and peas most problematic Grape tomatoes too variable in maturity and quality Sugar snap peas too variable in quality and condition Minimize storage before preparing vegetable tray

    Compromise atmosphere-tolerable atmospheres 3%O2 +7%CO2 or 10%O2 +12%CO2 Broccoli and celery benefited Grape tomatoes and carrots tolerant Sugar peas slightly damaged

    Conclusions

    Slide Number 1Slide Number 2Fresh Produce Executive Forum Webinar Series Slide Number 4Postharvest Handling Challenges:Fresh-cut Veggie TraySlide Number 6Slide Number 7Slide Number 8Slide Number 9Grape tomatoes & postharvest handingSlide Number 11Slide Number 12Slide Number 13Grape Tomato Quality ChangesTest#1 and #2Slide Number 15Slide Number 16Slide Number 17Slide Number 18