Wheat bran is one of the major dietary fibre sources widely used in food.The effects of particle size and addition level of wheat bran on the texture properties of dry white Chinese noodle(DWCN) were investigated in this study.Noodles were made of Shannong 2 wheat flour mixed with wheat bran at four different levels(5%,10%,15% and 20%) and of four different particle sizes(0.16-0.43 mm,0.43-1.0 mm,1.5-2.0 mm and 2.0-2.5mm).The results showed that the addition level and particle size of wheat bran had considerable influence on noodle texture properties.In general,the breaking strength,flexibility and area integrals of the strength curve decreased obviously as wheat bran particle size and addition level increased.The dry noodle breaking strength(DNBS) showed a downtrend with increasing addition level when the bran size was larger than 0.43 mm.At 5% addition level,there were no differences in DNBS,which was obvious when more than 10% wheat bran was added.For the fine bran(size 0.43 mm),there was only a slight decrease in dry noodle flexibility(DNF) when the addition level of wheat bran was less than 10%.But for coarse bran,there was obvious effect of addition level on DNF even though the addition was less than 5%.With increasing particle size and addition level of wheat bran,the hardness,gumminess and chewiness of cooked noodle decreased and adhesiveness increased.However,the changing trends of springiness and cohesiveness were not consistent.For fine bran,there was no significant decrease in hardness when the addition level was less than 10%,but for coarse bran,there was a remarkable decrease.For medium and coarse bran,addition of wheat bran had no effect on cohesiveness,springiness or resilience of noodles at 5%-15% addition levels.We suggest that 10% and less fine bran or 5% and less medium bran should be required to produce fibre-rich DWCN.

As one of the most effective enzymatic modification methods of protein, papain hydrolysis is applied widely in food production, accompanying starch pasting frequently in order to improve industrial quality. Effects of the papain hydrolysis on flour pasting properties were investigated in five papain/flour concentrations and five time-treatments. The structure of starch and protein networks in slurry was investigated under microscope before and after pasting. Results showed that papain hydrolysis influenced the pasting properties of wheat flour significantly through affecting structural characteristics, amylase activity and exothermic transition, especially during the early stage of hydrolysis. Peak viscosity, trough, final, integral area, and setback significantly decreased along with the increasing concentration of papain. Both hydrolysis time and concentration of papain had obviously effect on the breakdown. Pasting temperature and pasting time increased significantly with the enhancement of papain concentration. Hydrolysis time exerted minor effect on the pasting temperature and pasting time. The average peak time was slightly prolonged by lower concentration of papain, otherwise slightly shortened by higher concentration.