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Effects of Ozone Treatment on Storage Quality of Qiushui Pear

Author: ZhaoZheng
Tutor: LiDaPeng
School: Shandong Agricultural University
Course: Agricultural Products Processing and Storage
Keywords: Autumn pear Ozone Hypothermia RT-PCR Physiological quality Antioxidant activity
CLC: TS255.3
Type: Master's thesis
Year: 2010
Downloads: 76
Quote: 0
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Abstract

The Chinese pear producing countries, the country pear production in 2008, according to FAO statistics of 13676Kt, ranking first in the world. Pear fruit has a sweet taste, the smell and taste of the spirit of joy, loved by consumers. Pear belongs to the respiratory climacteric fruit, highly vulnerable to the impact of the storage environment leading to quality deterioration. Therefore, the study pome indeed stored for the physiological changes in the process characteristics and the applicable storage technique has important significance. Ozone is an unstable compound, with strong oxidation and disinfection effect. In many countries, the ozone is widely used in the food industry. Certain concentration of ozone can be effectively reduced and the elimination of harmful substances in the gas in the storage environment, such as ethylene, acetaldehyde, etc., instead interested in environmental pollution caused by the ozone, so called \Autumn pear, the test for the test materials, take normothermic and hypothermic two storage temperature, storage physiology of ozone treatment Autumn pear quality and its anti-oxidative activity; technical analysis by RT-PCR room temperature storage conditions, the ozone treatment Autumn pear fruit ethylene synthesis and signal transduction gene expression. The study found that: 1. Room temperature storage conditions, the ozone treatment can effectively maintain youthful pear fruit storage physiology quality, delaying senescence. High concentrations of ozone treatment (21.4mg / m ~ 3) in the Autumn pear early storage play a good effect, but prolonged treatment led to a rapid decline in fruit quality. The optimal concentration of ozone treatment (2.14mg / m ~ 3,6.42 mg / m ~ 3) play better storage 6.42mg / m ~ 3 concentration of ozone treatment preservation effect is most significant (p lt; 0.05). Room temperature storage conditions, the ozone treatment can significantly improve Autumn pear fruit antioxidant enzyme activities, maintaining a high fruit content of total phenolic and total flavonoids, effective suppression pear fruit PPO activity, maintaining a good fruit quality, delayed fruit browning occurs. Able to maintain high concentrations of ozone treatment (21.4mg / m ~ 3) in the early storage fruit higher antioxidant enzyme activity, and the late storage, the antioxidant activity decreased rapidly, leading to rapid quality decline. Appropriate low concentrations of ozone treatment (2.14mg / m ~ 3,6.42 mg / m ~ 3) can effectively keep Autumn Pear Fruit higher antioxidant enzyme activity, 6.42mg / m ~ 3 concentration of ozone treatment effect was more significant (p lt; 0.05). Ozone treatment of ethylene synthesis and signal feelings related genes may exist indirect role postharvest ethylene biosynthesis by inhibiting P-ACS1 gene expression and regulation; lowered P-ERS1 P-ETR1 in and the P-CTR1 gene reduced expression of the sensitivity of the fruit to ethylene. Temperature ozone treatment better maintain youthful pear fruit storage quality extend fruit storage periods, the difference was not statistically significant (p gt between different concentrations of ozone treatment of early storage; 0.05), while 21.4mg / m ~ 3 ozone better handling in the the late storage effect of the Autumn pear. In addition, the low temperature ozone treatment can effectively improve the fruit antioxidant enzyme activity, inhibition of PPO activity, slow down the aging of the fruit. Concentration of 21.4 mg / m ~~ the fresh ozone treatment better. In short, the appropriate ozone treatment can systematically improve Autumn pear fruit antioxidant capacity to maintain storage quality, extend shelf life. In this study, results-Autumn pear ozone storage technology provides a theoretical basis and technical support.

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CLC: > Industrial Technology > Light industry,handicrafts > Food Industry > Fruits, vegetables,nuts processing industry > Fruit and vegetable processing and preservation
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