Study On Decay Control Technique Of Post-Harvest Grape During Logistics With Acetic Acid Alternative To Sulfur Dioxide

Grape, a very welcomed fruit for its good taste and abundant nutrition, is widely cultivated in China. But it is susceptible to infection by gray mold, resulting in decrease in nutrition and great economic losses. SO2 preservative is most widely used in anti-decay and fresh keeping of post-harvest grape for its ideal preservative effect. But its food safety is widely concerned, besides, SO2 is easy to blanch grape, so it is imperative to seek a successful preservation methods without sulfur dioxide at home and abroad. Acetic acid has no-pollution and no-harm to people's health, which has been experimented on a variety of fruits and vegetables. Based on former researches, the paper aimed to seek the optimal dose of AAC fumigation, study the effect on quality of post-harvest grape and determine its feasibility. The results showed that:1. Four independent variables including ACC concentration, time, frequency, and temperature of fumigation were investigated through the single factor experiments and the optimum fumigation condition were 8 ?L/L AAC concentration fumigation one time with 2 h at 20 o C were determined, which could inhibit grape decay significantly and the effect was as well as SO2 preservative. After 30 days, the decay rate of AAC treatment was 5% ~ 8%, the decay control effect of which was as good as SO2 preservative, which was significantly lower than that of control.2. The effects of SO2 preservative and 8 ?L/L ACC fumigation on preservative quality of Kyoho grape under 5 oC and 10 oC were further compared and the results showed that the decay and berry drop rate of sulfur dioxide and AAC treatments were lower than that of the control group in 30 days on shelf and the organoleptic evaluation, stem water content,antioxidant activity, total phenolics and flavonoids of the two treatments had no significant differences. Besides, the stem water content and solid acid ratio in grape of AAC treatment were both higher than that of other treatments.3. The effects of ACC fumigation on preservation of red globe grape, green globe grape and summer black grape were investigated and the results showed ACC fumigation(8 ?L/L)controlled the decay rate effectively, reaching the preservative effect of SO2, the quality of grapes was well maintained. These results indicate that AAC is a viable alternative to SO2 for preserving grapes during logistics.The research can provide a reference for the commercial application of AAC on grape preservation.