?????????????????? (Controlled Atmosphere, CA) ??? ??????????????????? (Modified Atmosphere, MA)

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?????????????????? (Controlled Atmosphere,
CA)??? ??????????????????? (Modified
Atmosphere, MA)
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• ???? supplement technology ?????????????????
  ???????????????????? (short-term storage)
  ??????????????????????? (long-term storage)
  ????????????????????
• Both CA/MA ??????????????????? ?
  ???????????????????????????????????????? ??????
  78.09 N, 20.95 O2, 0.93 argon, 0.03 CO2
• ????????? CA/MA ??? ?????????????? CO2 gt3 ?????
  O2 lt5
• CA ?????????????????????????????????????? O2 ???
  CO2 ?????????? ???? container ???? cargo
  ??????????????
• MA ?????????????????????????????????? O2 ??? CO2
  ?????????????????????????????????????????
  container ???? packaging ??????

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????????????????????????????????????????? CA
????????????????? ??????
gt12 ????? 6-12 ????? 3-6 ????? 1-3 ????? Nuts ?????????????????? Apples (?????????), pears ????????? ???? Asian pears ????? cherry ????? ?????? ????
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?????????????? CA ????????????????????????????????
????????
???????? CA ??????
???????????????????? chilling injury ????????????? ???????????????????? - ????? ?????? ???????? ?????? ????????? - ?????, strawberry, cherry, berry ????? - ????????????, broccoli, lettuce, minimally-processed products
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????? CA

• ????????????????
• ?????????? (ripening) ????????????????????
  (senescence) ???
• ???????????????
• ????????? ethylene
• ????????????? (softening) ????????????????????????
  ????????
• ??????????????? ethylene
• ????????????????? ????????????????
  ????????????????????
• ???????????????????????????

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????? CA (???)

• ???????????????
• ???????????????????? (irregular ripening)
• ???? off-odors ???? off-flavor ???????????????????
  ???????????? O2 (anaerobic respiration)
• ????????????????????? ??????????????????? ?
  ????????? ???? ??????? ??????? browning ???
  tissue
• ??????????????????????????????????????????
  periderm ???? root vegetables

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??????????????

• Low O2 effects
• ?????????????????????????????????? cytochrome
  oxidase ?? ETC
• ???????????????????????????? ethylene
  ??????????????
• ????????????????????? O2 (????????????????)
  ??????? O21-3 ???????
• High CO2 effects
• ????????????? ethylene (CO2 is a competitive
  inhibitor of ethylene.)
• ???????????????????????????? 20
  ????????????????????? O2

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Supplement gas ??????? ? ??????

• CO 1-5 ????????? browning ?? fresh-cut products
• CO 5-10 ??????????????????????????
• Superatmospheric O2 (gt20 - 80)

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????????????????? CA/MA ??????????????

• ?????????????????????????????????? CA/MA
  ??????????
• Fresh-cuts
• Fruit

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?????????????????????????????????

• 1. Atmosphere generators
• O2 control
• ??? purge system ??? generator ???????????????????
  ?????????????? O2 ??????????
• ??????? nitrogen ?????????? O2 ??????????
  ????????????
• CO2 control ??? CO2
• ?????????? ???? dry ice ???????????????
• ??? CO2 scrubber ???? sodium hydroxide, ???,
  activated charcoal, hydrated lime (12 kg
  ????????? 1 ???)
• CO (1-10)
• Ethylene removal
• Ethylene absorbers (potassium permanganate
  ??????? activated charcoal)
• Ozone, catalytic burner, ventilation

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• 2. Hypobaric or low-pressure system (LPS)
• ??????????????????????????????? (vacuum) ?????
  partial pressure ?????????????? ???????? volatile
  ?????? ethylene ???????????????????????????
• ?????????????????????? O2 ?????????????????
• ?????????? CO2 ???? CO ???
• 3. Commodity-generated modified atmosphere
• ????? CO2 ????? O2 ???????????????????????????????
  ? restricted air-exchange barriers (???????????)
• ?????????? scrubbers ???

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• ?????????????????????
• Plastic film wraps ???????
• ??? polyethylene liner ????????????
• Plastic cover
• ????????????????????????????????????????????
• ??? waxes ???? surface coatings
• Plastic cover with diffusion windows
• ???????????????????? ???...?????????????????????

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Gas diffusion ?????????
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Gas Diffusion betweenExternal vs. Internal
Atmosphere

• ??????????????????????????????????????????????????
  ???????????????????????????????????
• ??????????????????????????????????????????????????
  ??????????????????????????????????????? (dermal
  system)
• ??????????????? barrier (???? ?????????
  (waxing/coating) ?????????????????????????)
  ??????????????????????????????????????????????????
  ????????????????????? (equilibrium) ???? ???
  ??????????????????????????????????????????????????
  ?

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Gas Diffusion (cont.)

• ??????????????????????????????????????????????????
  ?????????????
• Surface to volume ratio
• ???????????????????????? (?????????????????
  (stomata), ???????? (lenticels), ????????????
  cuticle, ?????????????????????)
• ???????????????????? ? ?????????
• ?????????????????????

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• 4. Atmospheres during transit
• MA ?? containers ???? ???? Tectrol system
  ????????? TransFresh Corp. ????? container
  ??????? ???????? ??????????????? ???????????
  nitrogen ??????? O2 ?????????? CO2 ??? CO ??????
  scrubbers ?????? CO2 ??? ethylene
• MA ?????????????? polyethylene plastic ????
  pellet ???? stack ??????????????????????????
  ????????????????????????????? ?????? strawberry,
  cherry ??????? (?????)
• MA ??????????? unit ??? shipping container
  ??????????????????????????????????????? ????
  ?????? polyethylene liner ???????????? cherry
  ???? polyethylene bags ??????? (Bananavac system)

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CA ?? strawberry
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Controlled atmosphere (CA) in Strawberry
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• 5. Modified atmosphere packaging (MAP)
• Commodity-generated or passive MA
• ??? plastic film ?????????????????????????????????
  ???????????????? ???????????? O2 ?????? ??? CO2
  ??????????????????????????????????
• ?????????????????????????????????
• Active MA
• ????????????????????????????????????? vacuum
  ??????????????????????????????????????????????????
  
• ????????????????????????????????? CO2 O2 ????
  ethylene
• ??????????????????????????? ??????????????

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???? plastic films ?????????? ???? LDPE
(low-density polyethylene), PVC (polyvinyl
chloride) ??????????????????? Polyester ???
Saran ???????????????????????????????????
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