Study On The Wheat Bran-based Fat Substitute

China is the big producer of wheat, and wheat bran,the major by-product in the wheat processing,which has a large yield of 30 million tons in 2008,but low utilized. In the study, wheat bran-based fat substitute(WBFS) was prepared by using a suitable enzyme and processing condition to hydrolyze the wheat bran starch to low DE value of 10 before sprying dry of supernatant.Then the properties of WBFS was studied compared with the regular fat replacer(DE3 maltodextrin).And finally,the application of WBFS in fat reduced ice cream was investigated.The preparation process of WBFS with low DE value was investigated.The wheat bran starch was pasted at 65℃for 10 min,and using medium temperature amylase to hydrolyze the starch.Under the condition of that:70℃,ratio of material to water 1:20,natural pH(6.5),hydrolyzing time 5min, when added enzyme is 0.3u/g, DE3.2 WBFS could be obtained, and when added enzyme is 0.9u/g, DE 8.9 WBFS could be obtained. In addition,the powder of WBFS can be obtain by sprying-dry at the following condition:inlet temperature 200℃, outlet temperature 80℃, the pump velocity 20mL/min.The analysis of WBSF composition show that theWFFS3.2 composed of 70.03% polysaccharide, the Mn and Mw molecular distibution of the maltodextrin is 19628,40766, theWFFS8.9 composed of 74.12% polysaccharide, the Mn and Mw molecular distibution of the maltodextrin is 19484,38688. Compared with the DE3 maltodextrin,DE3.2 WBFS and DE8.9 WBFS show the following properties:the moisture absorption , water bingding,oil bingding,foam capability,emulsion capability,foam stablity,emulsion stablity and viscosity of WBFS are better than those of DE3 maltodextrin,and less than 4 times of freezing and thawing cycle,the WBFS exibits good qulity as well as DE3 maltodextrin Finally,granularmetric analysis show more than 50% particals of WBFS are bellow 10μm, which is suitable for fat substitute.And in general, the DE8.9 exibits best properties of all.In view of the good properties of WBFS, the DE 8.9 WBFS was used in process of fat reduced ice cream, and the result demonstrated that:the ice cream, whose medium or full fat was substituted with WBFS, exibit good quality as well as the full fat ice cream, and what is more,it has reduced the fat content of ice cream.Therefore, the WBFS will have good prospects.