Effects of microencapsulated high-fat powders on the empirical and fundamental rheological properties of wheat flour doughs

Microencapsulated high-fat powders are a healthy and convenient alternative to fats normally used in cereal-based products. In powder form they are ea sier to use than block fat. Microencapsulation involves dispersion of the f at using homogenization. The globules are then fixed by spray-drying. Empir ical and fundamental rheological tests were conducted on doughs containing commercial vegetable fat and four microencapsulated high-fat powders. The d oughs were compared with a standard dough containing no fat. The powders co ntained 70% vegetable fat or milk fat. The encapsulating agent used was eit her sodium caseinate or whey protein concentrate (5-10%). Sucrose or lactos e were also present in the powders (20-25%). The powders were manufactured at low- or high-pressure homogenization. Farinograph and extensigraph tests were performed on all doughs. Dynamic oscillation tests were conducted in the linear viscoelastic region of the dough. Addition of fat and microencap sulated high-fat powders produced using low-pressure homogenization reduced the complex modulus of the doughs. The results showed an increase in phase angle with incorporation of commercial fat and the microencapsulated high- fat powders. Scanning electron microscopy was conducted to examine the effe cts of the additives on dough structure. This study demonstrated that micro encapsulated high-fat powders, especially powders produced using low-pressu re homogenization, had some beneficial effects on dough rheology when compa red with doughs produced with commercial fat.