Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development...Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development of the walnut industry.This study was aimed to investigate the impacts of temperature and packaging methods on the storage quality and oxidative stability of walnuts.The Wen 185 walnut variety was selected,and the physical-chemical and nutritional indexes of walnuts stored for 42 weeks under different temperatures(18℃,4℃,and room temperature)and packaging methods(vacuum light-exposed,vacuum light-proof,vacuum-ra-diation light-exposed,vacuum-radiation light-proof,nitrogen-filled light-exposed,nitrogen-filled light-proof)were measured.The results showed that low temperatures,especially18℃,in combination with vacuum lightproof packaging,could effectively suppress the increase in oxidative stability indicators such as acid value(AV)and peroxide value(PV),and maintain high retention rates of nutritional indicators like tocopherol and phytosterol.This study has elucidated that low temperatures and appropriate packaging methods play the crucial roles in maintaining the quality and oxidative stability of walnuts during storage.It has provided comprehensive and valuable data support and theoretical basis for the scientific storage of walnuts,contributing to the devel-opment of the walnut industry and the guarantee of product quality.展开更多
In order to select an appropriate deacidification process and improve the quality of walnut oil,low-temperature cold-pressed crude walnut oil was used as raw material.Deacidified walnut oil was prepared using three de...In order to select an appropriate deacidification process and improve the quality of walnut oil,low-temperature cold-pressed crude walnut oil was used as raw material.Deacidified walnut oil was prepared using three deacidification processes:chemical deacidification(CD),adsorption deacidification(AD),and molecular distillation deacidification(MDD).The physicochemical properties,nutritional components,and in vitro antioxidant activities of the resulting deacidified walnut oils were comparatively analyzed.The results indicate that the fatty acid content in walnut oil exhibits fluctuating changes during the three different deacidification processes.The MDD shows a higher deacidification rate,reaching 94.06%,which is superior to the other two methods.Additionally,the AD retains more total phenols and tocopherols,with retention rates of 95.79%and 74.62%,respectively;whereas MDD is more effective at retaining phytosterols,achieving a retention rate of 98.09%.All these methods displayed positive impacts on the in vitro antioxidant capacity and oil stability of walnut oil,with ferric-reducing antioxidant power(FRAP)content and oxidative stability time were significantly reduced.-whencompared to the untreated crude oil Among them,AD had the greatest impact on oxidative stability index(OSI),with its decreasing from 2.06 h to 0.82 h.Overall,compared to CD or MDD,the AD has best application prospects in preserving nutritional components.展开更多
基金Key Technology Research and Development Program in Autonomous Region(2022A02009)Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2021-OCRI).
文摘Walnuts are rich in a variety of nutritional components.However,due to their high content of unsaturated fatty acids(UFAs),the quality of walnuts tends to decline during storage,which adversely affects the development of the walnut industry.This study was aimed to investigate the impacts of temperature and packaging methods on the storage quality and oxidative stability of walnuts.The Wen 185 walnut variety was selected,and the physical-chemical and nutritional indexes of walnuts stored for 42 weeks under different temperatures(18℃,4℃,and room temperature)and packaging methods(vacuum light-exposed,vacuum light-proof,vacuum-ra-diation light-exposed,vacuum-radiation light-proof,nitrogen-filled light-exposed,nitrogen-filled light-proof)were measured.The results showed that low temperatures,especially18℃,in combination with vacuum lightproof packaging,could effectively suppress the increase in oxidative stability indicators such as acid value(AV)and peroxide value(PV),and maintain high retention rates of nutritional indicators like tocopherol and phytosterol.This study has elucidated that low temperatures and appropriate packaging methods play the crucial roles in maintaining the quality and oxidative stability of walnuts during storage.It has provided comprehensive and valuable data support and theoretical basis for the scientific storage of walnuts,contributing to the devel-opment of the walnut industry and the guarantee of product quality.
基金Key Technology Research and Development Program in Autonomous Region(2022A02009)Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2022-OCRI).
文摘In order to select an appropriate deacidification process and improve the quality of walnut oil,low-temperature cold-pressed crude walnut oil was used as raw material.Deacidified walnut oil was prepared using three deacidification processes:chemical deacidification(CD),adsorption deacidification(AD),and molecular distillation deacidification(MDD).The physicochemical properties,nutritional components,and in vitro antioxidant activities of the resulting deacidified walnut oils were comparatively analyzed.The results indicate that the fatty acid content in walnut oil exhibits fluctuating changes during the three different deacidification processes.The MDD shows a higher deacidification rate,reaching 94.06%,which is superior to the other two methods.Additionally,the AD retains more total phenols and tocopherols,with retention rates of 95.79%and 74.62%,respectively;whereas MDD is more effective at retaining phytosterols,achieving a retention rate of 98.09%.All these methods displayed positive impacts on the in vitro antioxidant capacity and oil stability of walnut oil,with ferric-reducing antioxidant power(FRAP)content and oxidative stability time were significantly reduced.-whencompared to the untreated crude oil Among them,AD had the greatest impact on oxidative stability index(OSI),with its decreasing from 2.06 h to 0.82 h.Overall,compared to CD or MDD,the AD has best application prospects in preserving nutritional components.
