EFFECTS OF SPINACH (Spinacia oleracea) POWDER ON THE PHYSICAL, PHYSIOCHEMICAL AND SENSORY QUALITIES OF BISCUITS

Abstract

Low-calorie and high-fiber vegetable powder supplemented biscuits have a great demand among the biscuit consumers. Therefore, an attempt was undertaken to prepare composite biscuit supplementing wheat flour by spinach powder. A multistoried universal cabinet dryer, developed in the laboratory of Food Engineering and Technology department, was used to dry raw spinach at a temperature of 55-60 0C and powder was prepared by grinding and sieving through 300 MSI mesh. The powder was found to be rich in protein, fiber, fat and ash but low in carbohydrate and energy compared to wheat flour. Three biscuit samples were prepared by supplementing wheat flour at the rate of 3%, 5% and 7% those were coded as F1, F2, and F3, respectively. Further, one control sample was prepared to compare quality of the proposed samples. Physical, physiochemical and sensory quality of the samples were evaluated. Spinach powder incorporation increased weight, diameter and density of the biscuits and decreased thickness, spread ratio and energy value compared to sample C. Lower values of moisture content 3.26%, 3.15% and 3.12% and fat content 14.67%, 14.57% and 14.74% were obtained in case of F1, F2 and F3 sample than sample C (moisture content 3.85% and fat 20.12%). Spinach powder enhanced protein, fiber, ash, and carbohydrate content (from 6.53%, 1.16%, 1.54%, and 66.72% up to 10.18%, 1.93%, 3.7% and 69.75% respectively) in F1, F2 and F3 samples. The biscuits were found to be rich in essential minerals like calcium, iron and phosphorus ranged from 123.67 to 261.49 mg/ 100g, 1.20 to 5.19 mg/ 100g and 61.46 to 112.87mg/ 100g respectively. Furthermore, ANOVA analysis showed significant differences in sensory attributes (color, flavor, texture, taste and overall acceptability) of the biscuits samples. The preference values for all the attributes are higher for control sample. Among the composite biscuit samples F1 (supplemented with 3% spinach powder) obtained higher scores for color, flavor, texture, taste and overall acceptability (7.2, 7.13, 7.0, 7.2 and 7.73 respectively). The current study revealed higher amount of nutrition in all the composite biscuits with suitable formulae and biscuit with 3% spinach powder (F1) was mostly preferred by the consumers.