Effect of Replacement of Wheat Flour with Sweet Potato Flour on Quality Characteristics of Muffins

Abstract

Sweet potato mixed wheat composite flour could make a protein rich product with good bai: -: qualities, which would increase the economic value. Therefore, a research was carried ou: develop a low gluten muffin, supplemented with sweet potato flour and to assess its nutritii:, and sensory qualities. The fresh roots of sweet potato (var. Wariyapola Red) w€re per :: washed and cut into thin slices. The slices were washed and dried in the dehumidifier drte: ,- 60'C for 12 hrs, The chips were ground into flour using an electric grinder, sieved through - - nm sieve and packed in air tight glass containers. The sweet potato flour was added in diffe:=-- amounts as an ingredient during the preparation of muffins. Different composite blends of n':.=. ' flourandsweetpotatoflourweremixedintheratiosof 100:00,80:20,70:30,60:40, and5L'i The muffins were analyzed for nutritional qualities such as moisture, ash, protein, fat, t-l::- vitamin A, calcium, iron, phosphorus and antioxidants, physical properties of weight and volL.:.' . and sensory attributes like colour, texture, taste, flavour and overall acceptability. . -, nutritional analysis revealed that the moisture, ash, fiber, vitamin A and calcium content t', : -:, increased from 8.73 to 1L^950/o,1..L4 to 2.570/o,6.51 to 12.L6% 11.15 to 358.5 pg/100g and 2 - : 29.5 mg/L009, while fat, protein, iron, and phosphorus content decreased from 2.89 to 1.6!: 8.74 to 7.630/o,3.18 to 1.98 mg/100g and 278.9 to 1.67.5 mg/700g, respectively with :-, increasing of the sweet potato flour from 0 to 50%. However, the total antioxidant activir, : increased from 542.2 to 786.4 mg AA/100g with the increasing of the sweet potato flour fro:- to 50%. Volume of the muffins decreased from 105.25 cme to 91.85 cm3 mean while weigh: . the muffin increased from 87.1 gto 96.4 g with increasing of sweet potato flour substitution. l - . sensory assessment showed that there were significant differences [p<0.05) ?mong -.: : treatments in terms of colour, texture, taste, aroma and overall acceptability. The mean sens- *, scores showed that consumers preferred the muffins made from L00o/o wheat flour hor,r'e'.=' muffins from the composite flours of 30o/o sweet potato flour substitution was also well accep:=': by the panelists. The muffins made from 30% sweet potato flour and 70o/owheat flour had ::, comparable nutritional, physical and sensory attributes to the 100o/o wheat flour muffinS. T::, outcome of the present study could be be used as valuable information for the developmen: : ' high fiber-low gluten muffins which is beneficial for human health with low cost of production