不同加工精度对面粉中脂肪酸含量影响的分析

INVESTIGATION ON THE EFFECT OF PROCESSING ACCURACY ON FATTY ACID CONTENT IN FLOURS

目的测定全麦粉、特一粉和麦芯粉中脂肪酸的含量,比较不同加工精度对其影响,为居民的合理膳食提供指导。方法选取13个具有代表性的小麦品种分别加工成全麦粉、特一粉和麦芯粉,经气相色谱仪分析,内标法定量,以峰面积计算脂肪酸含量。结果全麦粉、特一粉和麦芯粉中都检出棕榈酸、硬脂酸、油酸、亚油酸、二十碳烯酸和α-亚麻酸六种脂肪酸,这三类面粉脂肪酸含量总和分别为1871.9、1157.7和1173.5 mg/100g,不饱和脂肪酸含量均大于75%,其中亚油酸在三类面粉中含量均最高。经显著性检验,全麦粉中各个脂肪酸含量均显著高于同品种的特一粉和麦芯粉(P<0.05);而特一粉和麦芯粉中脂肪酸含量无显著差异(P>0.05)。结论小麦粉经加工剥皮处理,各种脂肪酸含量显著降低,结合其他营养物质含量变化,在保证营养和口感的前提下,建议居民选择全麦粉。

Objective To determine the fatty acid content in three kinds of flours and investigate the effect of food processing on the fatty acid content,and finally provide the residents with guidance for reasonable dietary intake.Methods A total of 13 representative wheat cultivars were selected and processed into whole wheat flour,high grade flour and wheat core flour,respectively.The fatty acids in all the samples were determined by using gas chromatography based on the internal standard method.Results Six fatty acids,including palmitic acid,stearic acid,oleic acid,linoleic acid,cis-11-eicosaenoic acid andα-linolenic acid were all detected in three kinds of flours.The total contents of 6 fatty acids in wheat flour,high grade powder and wheat core powder were 1871.9 and 1157.7 and 1173.5 mg/100 g,respectively.The unsaturated fatty acids accounted for more than 75%,with linoleic acid coming out on the top.According to the test,the content of various fatty acids in whole wheat flour was significantly higher than that in the homologous high grade flour and wheat core flour;No significant difference was observed between the high grade flour and wheat core flour.Conclusion The fatty acid contents decrease in high grade flour and wheat core flour after food processing.Considering the changes of other nutrients,it is recommended to increase dietary intake of whole wheat flour on the premise of ensuring nutrition and taste.