竹笋膳食纤维对冻藏过程中面团加工特性、水分分布及微观结构的影响

Effect of bamboo shoots dietary fiber on processing characteristics and water distribution during dough freeze storage

竹笋膳食纤维由于其具有独特的理化特性,可显著改善冷冻面制品的品质。采用流变仪、低场核磁和扫描电镜等手段,研究了竹笋膳食纤维对面团恒温冻藏过程中蒸煮特性、流变特性、水分分布和微观结构的影响。结果表明:随着冻藏时间的延长,竹笋膳食纤维的添加减少了面团的蒸煮损失率,且在21 d时蒸煮损失率的减少最大,为6.58%;竹笋膳食纤维的添加增加了面团的吸水率,且在14 d时吸水率的增加最大,为24.82%;竹笋膳食纤维的添加使得冷冻面团的弹性模量和黏性模量提高;竹笋膳食纤维改变了冷冻面团的水分分布,主要体现为强结合水的先上升后下降和弱结合水的下降。扫描电镜研究发现,竹笋膳食纤维改变了冷冻面团的微观结构,使其淀粉颗粒与面筋网络排列更加细腻。研究发现,在冻藏过程中,在面制品中添加膳食纤维可以通过改善面团的水分分布和微观结构,从而影响了面团的蒸煮特性及流变学特性。

Bamboo shoot dietary fiber can significantly improve the quality of frozen noodles because of its unique physical and chemical properties. In this paper, the effects of bamboo shoot dietary fiber on cooking characteristics, rheological characteristics, water distribution and microstructure of frozen dough during frozen storage were studied by means of rheometer, low field nuclear magnetic resonance andscanning electron microscopy. The results showed that with the prolongation of frozen storage time, the addition of dietary fiber of bamboo shoots reduced the cooking loss rate of dough, and the maximum reduction of cooking loss was 6.58% at 21 days. The addition of bamboo fiber increased the dough＇s water absorption, and the maximum increase of water absorption was 24.82% at 14 days. The addition of bamboo fiber increased the elastic modulus and viscous modulus of frozen dough. The bamboo fiber changed the moisture distribution of frozen dough, which was mainly reflected by strong binding water rise and the weak binding water decrease. Scanning electron microscopy study found that bamboo shoot dietary fiber changed the frozen dough microstructure, which made starch granules and gluten network arrangement more delicate. The study found that in the process of frozen storage, adding the dietary fiber to flour products affected the dough＇s cooking characteristics and rheological properties by improving the water distribution and microstructure of the dough.