| Agaricus bisporus, China’s major export edible fungus which is not only delicious, but also has a high nutritional value and health-care function, loved by consumers. However, Because of its easy browning and weak storage that make the development of Agaricus bisporus industry has been greatly adversely affected. In this paper, calcium lactate, kojic acid and its complexes were used as main effectors, combined with strengthening mass transfer vacuum infiltration technology to explore the membrane stabilizer, enzyme inhibitor and its complex of Agaricus bisporus quality and physiological regulation mechanism. In order to provide theoretical and technical support to delay the Agaricus bisporus postharvest browning, and prolong the shelf life. The results were as follows:1. In vitro conditions, the inhibitory rate of calcium chloride, spermine and spermidine on Agaricus bisporus browning was negative; the maximum inhibition concentration of calcium ascorbate and calcium lactate were 11.75mmol/L and 16.22mmol/L, respectively, their maximum inhibitory rate werell.08% and 5.78%. Indicated that the membrane lipid stabilizer was not the way by control inhibition of enzyme activity to delay the browning.2. In vitro conditions, the maximum inhibitory concentration of kojic acid, histidine, glycine, EDTA and proline were 2.8mmol/L,5.16mmol/L,4.5mmol/L,2.04mmol/L, and 10.64mmol/L, in which the maximum concentration of the inhibitory rate reached 69.17%,23.58%,7%,6.84% and 4.67%. The rate of kojic acid was the best effect among them.3. In vitro conditions, the inhibitory rate of complex calcium chloride-kojic acid, calcium ascorbate-kojic acid, calcium lactate-kojic acid, spermine-kojic acid and spermidine-kojic acid were performanced as a superposition of composite system, showed that the enzyme inhibitors played a major effect on enzymatic browning.4. Whiteness value is a choice of the reference index, optimized the vacuum infiltration condition and the concentration of calcium treatment of Agaricus bisporus. The results showed that the biggest factor of whiteness was vacuum, followed by the concentration of calcium and the time of vacuum. The optimum conditions were:the vacuum was 0.05Mpa, the time of processing was 1.5min, and the optimal concentration were:calcium chloride 4.55mmol/L, calcium ascorbic 14.1mmol/L, calcium lactate 48.66 mmol/L.5. Investigated the influence of calcium chloride, calcium ascorbic, and calcium lactate treatment by vacuum infiltration on postharvest quality of Agaricus bisporus. The results indicated that the minimum loss of weight was calcium ascorbic treatment; All of the percentage cap opening, the browning degree, the respiration rate, the polyphenol oxidase (PPO) activity, the malondialdehyde content and the cell membrane permeability of calcium lactate treatment were the minimum of the three treatments. Thus calcium lactate was a better membrane stabilizer.6. Study on the influence of calcium lactate, kojic acid, calcium lactate-kojic acid complex treatments by vacuum infiltration on postharvest quality of Agaricus bisporus stored at 2±1℃ for 15days. The results indicated that the complex group was more effective both on balance of enzyme system and the stability of membrane than the other treatments. As a result, the complex had significant synergistic effect on postharvest quality and physiology of Agaricus bisporus.7. Electron microscope scanning was carried out on the late storage of Agaricus bisporus. The results showed that the cell membrane of calcium lactate-kojic acid treatment damaged slightly and produced less fragments compared with the calcium lactate and kojic acid which treated separately. |
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