ClO_2处理和包装方法对鲜核桃仁贮藏品质的影响

Effects of ClO_2 Treatment and Packing Methods on Storage Quality of Fresh Walnut Kernel

新疆核桃鲜果仁营养丰富,口感爽脆,然而极易褐变和腐烂,使其销售和贮藏存在瓶颈问题。为探讨安全、高效的核桃仁保鲜藏新方法,本文以新疆主产核桃品种"温185"薄皮核桃为研究对象,探究不同质量浓度(40 mg/L和80 mg/L)二氧化氯处理结合不同包装方法 (铝箔热封和铝箔真空包装)对新疆核桃仁保藏的效果,分析生理生化指标和脂肪抗氧化相关酶活的调控过程。结果表明:真空包装结合低浓度二氧化氯的处理方法可抑制鲜核桃仁的腐烂发生和呼吸强度,延缓褐变,有效保持贮藏期核桃仁的质量。通过营养物质的变化分析,蛋白质和糖分分解消耗显著降低,同时延缓酸价和过氧化值上升,显著降低核桃的主要有益成分——不饱和脂肪酸的氧化分解作用。其脂肪氧化相关的酶活(SOD酶和CAT酶)峰值被推迟10 d,有效降低了LOX酶活性,从而抑制自由基、过氧化物等有害物质产生,以此阐述鲜核桃仁品质保持的酶活调控途径。

Fresh walnut kernel was considered as delicious and nutritious, but hard to storage, it make an obstacles for selling and storage. The objective of this study was investigated a safe and highly efficient method for walnut preser-vation. The ＂WEN 185＂ thin-shell walnut which is the major production walnut varieties in Xinjiang province was used as test materials. Effects of different concentration （40 mg/L and 80 mg/L） chlorine dioxide （C102） treatment and different packing methods （Aluminum foil-heat sealing and aluminum foil-vacuum package） on storage quality and lipid oxidization enzyme activity of Fresh Walnut was explored. The results revealed that vacuum packing combined with low concentration of chlorine dioxide （40 mg/L） treatment could restrain decay rate, respiration intensity and browning of fresh walnut ker-nel effectively. The storage quality of walnut kernel was effectively preserved. The change of the nutrient in walnut kernel was analyzed, it was found the consumption of protein and sugar content was decreased significantly. Meanwhile the increase of acid value and peroxide value were delayed, it cause the oxidation decomposition of unsaturated fatty acid which is the main beneficial components of walnut kernel was significantly reduced. The peaks of fat oxidation related enzyme activity （SOD, CAT） was postponed 10 d, the activity of lipoxygenase was effectively reduced. It indicted that the production of harmful materials such as free radicals and superoxide were inhibited. The regulation pathway of fresh walnut kernel quality keep with enzyme activity was expounded.