冻藏过程中全麦粉速冻油条品质及风味的变化

Changes of Quality and Flavor of Whole Wheat Flour Quick-Frozen Fried Bread Stick During Frozen Storage

对比研究全麦粉/小麦粉速冻油条冻藏过程中挥发性风味物质以及脂质氧化程度的变化。分别采用电子鼻和顶空固相微萃取气质联用(HS-SPME-GC-MS)对样品风味化合物进行检测分析。并通过样品过氧化值(POV)和硫代巴比妥酸值(TBARS)的测定,进一步分析样品冻藏过程中的劣变程度。研究发现,速冻油条冻藏期间原有风味物质会逐渐散失,其内部脂质将持续发生氧化反应产生新的风味物质。相较于小麦粉速冻油条,全麦粉速冻油条内的风味物质不仅种类全面留存时间长,而且含量还更高。同时,冻藏过程中油条的POV和TBARS逐渐升高,但小麦粉油条的升高速率明显快于全麦粉油条。也证明了全麦粉中富含多酚等天然抗氧化剂,减缓了油条冻藏期间的劣变,延长了冷冻储存期间油条特殊风味的保留期,并且抑制了油脂初级和次级氧化产物的形成,改善了高油脂油炸食品的冻藏品质及稳定性。

The changes of volatile flavor substances and lipid oxidation degree of quick-frozen fried bread stick made of whole wheat flour/wheat flour during frozen storage were studied.The flavor compounds of fried bread stick were detected and analyzed by electronic nose and headspace solid phase microextraction GC-MS(HS-SPME-GC-MS).Besides,the deterioration degree of fried bread stick during freezing storage was further analyzed by the determination of peroxide value(POV)and thiobarbituric acid reactive substance(TBARS)of these samples.The original flavor substances from fried bread stick would be gradually lost,and the internal lipids would continue to produce new flavor substances via oxidation reaction during the frozen storage.Compared with wheat flour quick-frozen fried bread stick,the flavor substances in whole wheat flour quick-frozen fried bread stick with higher content and abundant species could retain for a longer time.Besides,The POV and TBARS of fried bread stick gradually increased during frozen storage,but the rising rate of wheat flour fried bread stick was significantly faster than that of whole wheat flour fried bread stick.For whole wheat flour fried bread stick,the formation of primary and secondary oxidation products of lipids was inhibited because whole wheat flour was rich in natural antioxidants,such as polyphenols,which slowed down the deterioration of whole wheat flour fried bread stick,prolonged the retention period of special flavor of fried bread stick during frozen storage,and improved the frozen-storage quality and stability of high fat fried foods.