Application Of Rye Arabinoxylan In The Baked Food

The analysis of "black pearl" rye flour major ingredients showed that protein content is 8.2%, total pentosans content is 6.1%, water-soluble arabinoxylan is 2.2%. Furthermore, the optimum extraction conditions by ethanol-precipitation were found that the ratio of material to water is 1:5, extraction temperature is 40℃ and extraction time is 2h. Gluten and rye arabinoxylan play an important role on the wheat flour farinograph properties and bread baking quality. The singal factor experimental results showed gluten and rye arabinoxylan improves the major wheat flour farinograph index, in different levels. The optimum addition levels of gluten and rye water are 2% and 3%.For this study, saturation D-optimum experimental design was used in which the dependent variable is loaf volume and the independent variables are gluten and rye arabinoxylan additional levels. The regression equation of the volume was: Y＝713.191+7.143X1+4.576X2-3.983X1X2The optimum combination of independent variables (X1, X2) were coded as 1, 0.3945, according to the regression equation of the volume. The optimum formulated scale of rye arabinoxylan to gluten is 3:1.4. A common rotatable second-order experiment was used to examine the loaf volume and loaf specific volume responses to independent variables (water absorption, mixing time). The regression equations of the loaf volume and specific loaf volume were:Y1=778.6+2.168 X1+15.826X2-11.612X12-34.119X22+38.25X1X2Y2＝5.18-0.00354X1-0.0103X2-0.0457X12-0.109X22+0.115X1X2。Maximum loaf volume can be obtained at the optimum combination ofwater absorption and mixing time (65%, 5min), according to the regression equation of the volume. Combining the equation with practical conditions, the optimum absorption level and mixing time were 64%, 5min.The loaf texture analysis showed that loaf hardness of formulated flour was lower than that of ordinary flour loaf, comparative to bread tailored flour loaf, and toughess and chewiness were higher than of ordinary flour loaf. Crumb structure is good. The good correlation between hardness, toughness and visual quality was found. The hardness and toughness could be good index to examine bread quality. The results of bread staling experiment showed in wheat bread supplemented with rye arabinoxylan and gluten, the decrease in moisture content, the increase in crumb hardness were lower than that in a control. The correlations between storage time and moisture content and hardness are significant. The correlation between storage time and toughness is not significant.