小麦粉加工精度对挂面储藏期间脂质稳定性的影响

Effects of Wheat Flour Processing Degree on Lipid Stability of Dried Noodles During Storage

研究不同加工精度小麦粉对挂面储藏期间脂质稳定性影响。结果表明,挂面储藏过程中,总脂和结合脂含量总体呈现下降趋势,游离脂含量先下降后升高再下降,脂肪不断消耗;游离脂肪酸值显著升高(P<0.05),低加工精度小麦粉制得的挂面脂质水解程度较高且水解速率快,12周后脂肪酸值略有降低;低加工精度的挂面脂肪酶活显著下降(P<0.05);低加工精度挂面亚油酸含量在0~12周显著上升(P<0.05),随后显著降低(P<0.05);GC-MS测定结果表明挂面中挥发性物质乙酸、己酸和壬酸含量明显升高,加工精度越低的小麦粉制得的挂面中酸性物质含量增幅越大,氧化酸败速度越快。因此,低加工精度小麦粉制得的挂面在储藏过程中脂质水解和氧化程度较高,脂质稳定性较低。

The effects of wheat flour processing degree on lipid stability of dried noodles during storage were studied.Results indicated,that during storage,total lipid and bound lipid content decreased.The free lipid content decreased first,then increased,and finally decreased.The free fatty acid value increased significantly(P<0.05),and noodles made from lower processing degree wheat flour(LPDWF)had higher levels and rates of lipid hydrolysis.After 12 weeks,FFAs slightly decreased.Meanwhile,noodles made of LPDWF had a higher reduction of lipase activity(P<0.05).In addition,the content of linoleic acid of noodles made of LPDWF increased significantly from week 0 to week 12(P<0.05),and then significantly decreased after that(P<0.05).The results determined by GC-MS indicated that acetic acid,hexanoic acid and nonanoic acid increased,and the lower the processing degree was,the higher the content was,showing a rapid lipid oxidation rate.To conclude,noodles made by LPDWF had high levels of lipid hydrolysis and oxidation,and lower lipid stability.