张继刚, 丁之恩, 梁进, 程江华, 杨松. 适宜微波处理保持山核桃贮藏品质[J]. 农业工程学报, 2016, 32(14): 284-292. DOI: 10.11975/j.issn.1002-6819.2016.14.038
    引用本文: 张继刚, 丁之恩, 梁进, 程江华, 杨松. 适宜微波处理保持山核桃贮藏品质[J]. 农业工程学报, 2016, 32(14): 284-292. DOI: 10.11975/j.issn.1002-6819.2016.14.038
    Zhang Jigang, Ding Zhien, Liang Jin, Cheng Jianghua, Yang Song. Suitable duration of microwave pre-treatment for maintaining postharvest qualities on pecan nuts during storage[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2016, 32(14): 284-292. DOI: 10.11975/j.issn.1002-6819.2016.14.038
    Citation: Zhang Jigang, Ding Zhien, Liang Jin, Cheng Jianghua, Yang Song. Suitable duration of microwave pre-treatment for maintaining postharvest qualities on pecan nuts during storage[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2016, 32(14): 284-292. DOI: 10.11975/j.issn.1002-6819.2016.14.038

    适宜微波处理保持山核桃贮藏品质

    Suitable duration of microwave pre-treatment for maintaining postharvest qualities on pecan nuts during storage

    • 摘要: 为了研究微波热处理对山核桃贮藏品质的影响,将新鲜山核桃(500 g)在微波(2 455 MHz,650 W)下分别进行1,2.5,3和5 min热处理,然后置于温度:(2±0.5)℃,相对湿度:70%~80%的环境中贮藏120 d。贮藏期间对山核桃营养成分,品质变化,感官指标进行监测。结果显示2.5 min的微波处理能够显著(P<0.05)延缓蛋白质、脂肪的降低,对脂肪酸和维生素E有较好的保存效果,此外,2.5 min微波处理能够减慢贮藏期间山核桃水分和可溶性糖的流失速度,维持较好的感官品质。同时2.5 min微波处理对脂肪酸败有很好的抑制效果,在贮藏120 d,山核桃保持了较好的品质。与2.5 min相比较,较短时间(1 min)和较长时间(3和5 min)微波处理没有提高山核桃贮藏期间的营养品质,1 min的微波处理对贮藏期间山核桃脂肪、蛋白、脂肪酸、过氧化值(peroxide value)、生育酚等营养几乎贮藏无影响(P>0.05),3和5 min处理显著(P<0.05)加剧了各项营养指标的衰败速度,因此2.5 min为适宜的微波处理条件。该研究为微波保鲜山核桃提供理论依据。

       

      Abstract: Abstract: Pecan (Carya illinoensis Koch), a kind of famous nutritious nuts in the world, and it is important to explore novel storage technology in protecting qualities against sharp losses of nutritional value and the decreased of sensory qualities. The objective of this study was to investigate the effect of microwave heat treatment on nutritional ingredients, quality variation, and sensory indexes. Fresh pecan nuts (500 g) were exposed to microwave heating for 1, 2.5, 3, and 5 min at a frequency of 2 455 MHz, power of 650 W and then stored at (2±0.5)℃ for up to 120 days. Change of contents in moisture, fat, crude protein, total soluble sugar (TSS) and tocopherol, fatty acid composition, peroxide value (PV), and the sensory quality were determined at regular interval during storage. The results showed that some constituents changed progressively with storage time, featuring decreases in contents of moisture, lipid and tocopherols and increases in TSS and PV. Microwave treatments indeed affected storage-induced chemical changes. This effect largely depended on duration of microwaving. Compared with the control (0 min ), microwave pre-treatment for 2.5 min significantly (P<0.05) delayed the degradation of crude protein and decrease of lipids, and thus preserved total unsaturated fatty acids and tocopherol content at the end of storage in comparison with untreated control. In addition, the above treatment also significantly (P<0.05) inhibited moisture loss, and increased total soluble sugar content, therefore, remained sensory qualities of fresh pecan during storage in comparison with untreated control. On the contrary, a shorter duration (1 min) of microwaving had little (P>0.05) effect, while longer duration (3 or 5 min) of microwaving accelerated (P<0.01) the storage induced changes. Only a medium duration (2.5 min) of microwave suppressed the chemical change. It is concluded that fresh pecan nuts exposed to 2.5 min duration of microwave treatment can be stored at (2±0.5) ℃ for up to 120 d without any adverse effect on PV, fatty acid composition, or tocopherol content. This study provided theoretical foundation for application of microwave treatment on maintaining the quality against decrease of fresh pecan during postharvest storage.

       

    /

    返回文章
    返回