Sharma, P.D.Kumari, Babita2020-12-072020-12-072020MT/PFE/493/2018-2019https://krishikosh.egranth.ac.in/handle/1/5810156404Ready-to-eat expanded snacks are part of the human diet, which are produced by extrusion cooking process. Maize is a major raw material for the production of extruded snack, which gives good expansion characteristic to the extrudates. In this study, Soybean and pomegranate pomace powder were added to maize in different proportions to improve the nutritional quality of the prepared extrudates. Extrusion cooking was carried out using a Twin Screw Extruder. Extrusion cooking experiments were conducted employing CCRD for four independent variables with five level each (Feed proportion -75:23:2, 75:21:4, 75:19:6, 75:17:8, 75:15:10; Feed rate - 10,11,12,13,14 kg/h; Screw speed - 150, 175, 200, 225, 250 rpm; Barrel temperature - 95, 105, 115, 125, 135oC). A total of 30 combinations of these independent variables were formed to see the effect on different dependent variables like Expansion ratio, Bulk density, Water activity, Water absorption index, Colour score, and Overall acceptability. Optimization was carried out to select the best combination for maximizing Expansion ratio, Water absorption index, Colour score, and Overall acceptability and minimizing Water activity and Bulk density. During experiments, the best combination was generated on the basis of optimization by response surface methodology. Second order multiple regression equations were developed for all the dependent variables which were optimized using response surface methodology. The composite flour comprising of maize, soybean and pomegranate pomace powder in the ratio of 75:21:04 produced the most acceptable extrudates in terms of optimum values of Expansion ratio - 3.7, Water absorption index – 5.86, Color score – 7.78, Overall acceptability – 7.57, Bulk density -57.5 kg/m3, Water activity – 0.31. The experimental data for response were in close agreement with the optimized solution obtained from RSM as Feed proportion – 75:21:4, Feed rate -11 kg/h, Screw speed - 225 rpm, Barrel Temperature -125ºC. The prepared optimized extrudates also had well balanced acceptable range of the nutrition (total carbohydrate-78.50%, Protein- 10.40%, fat- 4.65%, fibre- 1.80%, moisture – 3.20% and ash- 1.50%).EnglishThesis