储藏条件对‘凤丹’籽粒酶活性及籽油品质的影响

Effects of storage conditions on the seed enzyme activity and seed oil quality of‘Fengdan’(Paeonia ostii)

【目的】探究油用‘凤丹’籽粒适宜的储藏条件以及各储藏条件下籽粒的保质期,为油用‘凤丹’籽粒的采后储藏加工提供参考。【方法】以当年采收的‘凤丹’籽粒为材料,分别以室温散装、室温真空包装、4℃散装、-20℃散装共4种储藏方法对籽粒进行为期1 a的储藏。储藏期间每隔30 d测定籽粒的酶活性(过氧化物酶POD、脂肪酶LPS和脂肪氧合酶LOX)、籽粒出油率以及所提取籽油的油脂品质(酸值、碘值、过氧化值)和脂肪酸含量(亚麻酸、亚油酸、油酸等)。【结果】在整个储藏期间,‘凤丹’籽粒的POD活性、出油率以及所提取籽油的碘值、亚麻酸含量、亚油酸含量、不饱和脂肪酸总含量呈不同程度的下降趋势;所提取籽油的酸值、过氧化值、油酸含量呈不同程度的上升趋势;‘凤丹’籽粒的LPS、LOX活性呈先上升、后下降的趋势。与室温散装储藏对比,室温真空包装储藏、4℃散装储藏和-20℃散装储藏均能有效抑制‘凤丹’籽粒和所提取籽油的劣变。综合各项指标可知,室温散装、室温真空包装、4℃散装、-20℃散装条件下储藏‘凤丹’籽粒分别不宜超过60、150、120、300 d。【结论】储藏环境的温度和氧含量对‘凤丹’籽粒的保质期有较大影响,结合生产实际,建议油用‘凤丹’籽粒的储藏环境应低温、少氧,且宜在半年内提取籽油。

【Objective】To provide references for the postharvest storage and processing of‘Fengdan’seeds,which were uesd for oil extraction,the suitable storage conditions and the shelf life of‘Fengdan’seeds under various storage conditions were investigated.【Method】In this study,‘Fengdan’seeds harvested that year were stored at room temperature in bulk,vacuum packaged at room temperature,bulk at 4℃,and bulk at-20℃for 1-year.Enzyme activity(POD,LPS,LOX)of the seeds,the seeds oil yield as well as oil quality(acid value,iodide value,peroxidation value)and fatty acid content(linolenic acid,linoleic acid,oleic acid,etc.)changes of the extracted seed oil were measured every 30 days during this period.【Result】During the whole storage period,the POD activity,extracted oil content,iodine value,linolenic acid content,linoleic acid content,and total unsaturated fatty acid content of‘Fengdan’seeds showed decreasing trends in different degrees.The acid value,peroxidation value,and oleic acid content of the extracted seeds showed increasing trends in different degrees.LPS activity and LOX activity in the‘Fengdan’seeds showed an initial increase followed by a decrease.The storage conditions,including room temperature vacuum packaged storage,4℃bulk storage,and-20℃bulk storage,could effectively inhibit the decay and the extracted seed oil of‘Fengdan’except for the room temperature bulk storage.Taking all the indicators together,seed stored in bulk at room temperature,in vacuum packaging at room temperature,in bulk at 4℃,and in bulk at-20℃should not exceed 60 days,150 days,120 days,and 300 days,respectively.【Conclusion】The temperature and oxygen content of the storage environment have a great influence on the shelf life of seed oil that is qualified for extraction from‘Fengdan’seeds,and combined with the practical production,it is suggested that the storage environment of oil using Paeonia ostii seeds should be low temperature and less oxygen,and the seed oil should be extracted within half a year.