| Grape is very easy to rot, threshing, stems dry, browning during the shelf life,which not only result in reduction in the nutritional value of the grape, but also cause great economic losses. This study was designed to explore the quality changes of red globe grapes and kyoho grape under different shelf temperatures, in order to find the suitable shelf temperatures and different temperatures corresponding to the shelf time. The main results were as follows:1. The effect of temperatures on the sensory quality including rot, the rate of threshing,the stems dry, and the nutritional quality such as soluble solids content, the content of stems moisture, solid acid ratio, titratable acid content, antioxidant activity, vitamin C, besides the functional components including the total phenol, the total flavonoids of the grape were: the lower the temperature, the better the quality; the longer shelf life, the temperature as low as possible.2. Stems dry was main limiting factors to affecting the shelf quality of red globe grape.From the decay rate and the stem water content analysis, rot and the stems dry of red globe grape at 15 °C and 20 °C, were obviously serious than those at 5 °C and 10 °C, the differences of nutrients and functional ingredients also showed the same rule at different temperatures.With bright green stems, good quality of fruit grain as assessment standards, shelf temperatures of red globe grape should be controlled ≤ 10 °C under shelf life 4 days, shelf temperatures should be controlled ≤ 5 °C.under shelf life 8 days, 12 days, shelf temperatures should be controlled < 5 °C under shelf life 16 days. And if not stems dry as limiting factors of the shelf life, with the quality of fruit grain as evaluation index, shelf temperatures were no more than 10 °C under 4-16 days of shelf life.3. Threshing, stems dry and rot were main limiting factors to affecting the shelf quality of kyoho grape. From threshing, weight loss and the content of stem water analysis, the rate of threshing at four temperatures had little difference under shelf life 4 days, the higher shelf temperatures, the higher the rate of threshing and weight loss, but which did not affect the value of the goods, threshing, weight loss and the stems dry of kyoho grape at 15 °C and20 °C, were obviously serious than those at 5 °C and 10 °C under shelf life 16 days, 12 days,which indicated that shelf temperatures of kyoho grape should be controlled ≤ 10 °C during shelf life. Considering all the quality indicators comprehensively, shelf temperatures of kyoho grape should be controlled ≤ 5 °C under shelf life 16 days and 12 days, shelf temperatures of kyoho grape should be controlled ≤ 10 °C under shelf life 8 days, shelf temperatures should be controlled ≤ 15 °C.under shelf life 4 days.4. Kyoho grape were sent in different treatments including 10 °C, 1-MCP treatment under shelf temperature 10 °C, in order to simulate shelf process, and the fruit qualities including rotting rate, off grain rate, soluble solids content, titratable acid, vitamin C,malondialdehyde, ethanol, antioxidant activity, etc were investigated. The results showed that soluble solids content, titratable acid content, vitamin C content, antioxidant activity, the stem water content of 1-MCP treatment under 10 °C on kyoho grape was significantly higher than10 °C treatment under the shelf life 0-8 days. Weight loss, the rotting rate, grain-dropping rate,malondialdehyde, and the ethanol content of kyoho grape without 1-MCP reatment were significantly higher than that of grape with 1-MCP treatment at 10 °C, which showed that1-MCP treatment can reduce the grain-dropping rate of kyoho grape and keep its good quality.Compared with control, 1-MCP treatment could better maintain the quality of the grapes and keep stems fresh. |
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