EFFECT OF DIFFERENT MODIFIED ATMOSPHERE PACKAGING TREATMENTS WITH LOW TEMPERATURE ON STORAGE QUALITY OF FRESH-CUT PINEAPPLE

In order to find a technique to keep storage quality of fresh-cut pineapple,the effect of different modified atmosphere packaging (MAP) treatments with low temperature on soluble solids,weight loss rate,browning degree,hardness,vitamin C,polyphenol oxidase activity and phenoloxidase activity of fresh-cut pineapple was investigated during storage by taking pineappale of bali variety as a test material.The results showed that modified atmosphere packaging treatments with low temperature could preserve storage quality of fresh-cut pineapple better than control group.The MAP treatment consisting of 4% O₂+5% CO₂+91% N₂was the best for keeping storage quality among the tested treatments,which could reduce the weight loss rate by 14.06 to 18.53 percent point,browning degree by 1.5 to 3 percent point,polyphenol oxidase activity by 14.11 to 60.04 U·min^-1·g^-1,phenoloxidase activity by 29.84 to 47.33 U·min^-1·g^-1and improve hardness by 3.87 to 12.59 N in contrast with the control group during storage.On the 20th day,vitamin C of treatment group was 12.22 mg/100 g higher than that of control group.Moreover,the MAP treatment consisting of 4% O₂+5% CO₂+91% N₂could lower enzyme activity,prevent the browning of fresh-cut pineapple and oxidation of vitamin C,extend the shelf life of fresh-cut pineapple from 4 to 15 days.