摘要
The effect of vacuum cooling on shelf life of organic chayote was investigated. Vacuum cooling processes of organic chayote shoot packed in perforated polyethylene package using different vacuum pressure reserving operation modes were experimented. The holding final pressures for vacuum-cooled organic cilantro packed in holed polyethylene bags were set at two different levels, namely at 10 and 11 millibar. The pressures were experimented with 3 levels of reserving time of 3, 4 and 5 minutes. The weight loss percentage of chayote shoot during precooling to the temperature of 8 ~ 1 ~C using reserving pressure of 10 milibars for 3, 4, and 5 minutes were 0.5, 0.7, and 0.9, respectively. For the weight loss percentage during precooling using reserving pressure of 11 milibars for 3, 4, and 5 minutes were 0.4, 0.5, and 0.5, respectively. The optimum parameter for vacuum cooling process of organic chayote shoot at the initial temperature of 19-23 ℃to 8 ±1 ℃was the reserving pressure of 11 mbar with reserving time of 5 minutes. The precooled organic chayote shoot was then stored at 8 ℃ for quality analysis. The results showed that vacuum cooling had no effect on the change of color, chlorophyll a, b and total chlorophyll. However, precooled organic chayote shoots showed better appearance than non-precooled vegetables. Vacuum cooling can reduce weight loss percentage. The amount of total soluble solids in organic chayote shoots increased with storage time. Precooled organic chayote shoot had longer shelf life of 8 days compared to normal storage life of 5 days.