บทคัดย่องานวิจัย

หมวดหมู่ : ฐานข้อมูลงานวิจัย

Pre-storage controlled atmosphere treatment of fruit and vegetables

Pitakserikul, Sumalee.

Ph.D., University of New South Wales (Australia), 1984.

1984

บทคัดย่อ

PRE-STORAGE CONTROLLED ATMOSPHERE TREATMENT OF FRUIT AND VEGETABLES.

This thesis reports on the effects of a short postharvest treatment of low oxygen and high carbon dioxide atmospheres on ripening and senescence of intact bananas, tomatoes, pears, apples, mangoes and potatoes.  The effects of low oxygen on s-adenosylmethionine (SAM) and 1-aminocyclo-propane-1-carboxylic acid (ACC) changes of bananas and tomatoes are also reported.  All produce were held in air at 20(DEGREES)C except for mangoes which were at 25(DEGREES)C.

 Exposure of preclimacteric bananas to low oxygen for several days followed by storage in air extended the time required for the fruit to ripen, as measured by the time to peak carbon dioxide and ethylene production, softening, loss of green skin colour and changes in soluble solids, titratable acid and pH.  Optimal conditions were < 1% oxygen for approximately 3-10 days.  The addition of carbon dioxide did not improve the effect of oxygen.  Treatment of the fruit with ethylene (at 10 (mu)l/l) before, during or after exposure to low oxygen reduced the time required for the fruit to ripen.

 Low oxygen treatment delayed the ripening time and the rise in ethylene production of Day Dream and Tropic tomatoes and Williams Bon Chretien, Buerre Bosc and Packham pears, however carbon dioxide production was not affected.  With postclimacteric Golden Delicious apples, low oxygen treatment had no effect on the ripening process during subsequent storage in air.  Storage of Kensington Pride mangoes in low oxygen for 5-7 days delayed softening by the end of the exposure period.  However, respiration and fruit softening then increased rapidly to be similar to control fruit.  Exposure of fresh and aged potato tubers to low oxygen for short periods had no marked beneficial effect on respiration or inhibition of sprout growth.

 Low oxygen had no effect on changes of SAM in preclimacteric bananas and tomatoes but caused an increase in ACC content by the end of the exposure period.  The increased amounts of endogenous ACC caused by low oxygen exceeded the amount of ethylene produced by the control fruit held continuously in air.  Low oxygen inhibited the conversion of ACC to ethylene.  .  .  .  (Author's abstract exceeds stipulated maximum length.  Discontinued here with permission of school.) UMI.