Khushboo Gupta

Process Optimization for Formulating Trigonella foenum-graecum and Gymnema sylvestre Added Vegetable Cereal Mix Using Response Surface Methodology

Trigonella foenum-graecum seeds and Gymnema sylvestre leaves are health promoting food ingredients which are particularly beneficial for individuals suffering from diabetes mellitus. In order to promote their incorporation in diet, vegetable cereal mix was formulated as a dried food product with extended shelf life, which could be easily reconstituted for consumption. Response surface methodology and central composite design were used in optimization of vegetable cereal mix. The objective was to devise the best combination of process variables and obtain optimal recipe having minimum fat, maximum fiber, in-range carbohydrate and maximum overall acceptability. Three quantitative controllable factors were selected for the experimental design: amount of Trigonella foenum-graecum, soaking time of Trigonella foenum-graecum and amount of Gymnema sylvestre as process parameters. Response variables were fat, fiber, carbohydrate and overall acceptability. Regression models and response surface plots were generated and adequacy was tested with regression coefficients and the lack of fit tests. Sensory, physico-chemical and microbiological analysis were undertaken for optimized recipe. The optimum recipe had 8.0 g Trigonella foenum-graecum with 8.0 hours soaking time and 5.0 g Gymnema sylvestre with 0.48 g fat, 3.01 g crude fiber, 29.84 g carbohydrate and 89.17 overall acceptability score. Results indicated that optimized product obtained good scores for all sensory attributes and had good shelf life. This vegetable cereal mix was nutritionally adequate and had desirable sensory quality.

Impact of Incorporation of Soyfibre and Processed Soyflour on the Sensory Quality, Nutrient Content and Glycemic Index of Rawa Idli

Glycemic index (GI) has proven to be a useful nutritional concept, providing insight into the relationship between foods and chronic diseases. Objective of present work was to study the impact of addition of soyfibre and processed soyflour on the sensory quality, nutrient content and GI of rawa idli. Idli was prepared using semolina and curd. Its three variants incorporating soyfibre, roasted soyflour and defatted soyflour (15%), respectively, having 50g available carbohydrate, were developed and subjected to sensory analysis. Estimation of moisture, ash, crude fibre, protein and fat was done. GI of test meals was calculated. All the rawa idlis had good acceptability. Soyfibre added idli was like plain idli in sensory attributes. Roasted soyflour added product had highest fat and protein. There was a significant difference between nutrient content of idlis (p<0.05). Plain idli had highest GI (66.50%). Soyfibre added rawa idli had lowest GI (37.22). Addition of soy in rawa idli significantly reduces the GI. Food Science Introduction A major risk factor of increasing prevalence of diseases, i.e., obesity, resulting hyper insulinemia and insulin resistance is the on-going nutrition transition with progressive shifts to a westernized diet high in saturated fat and sugars (Popkin 2002) and a high glycemic index (GI) diet. High GI diet may increase insulin secretion which in turn, may induce insulin resistance and predispose individuals to type 2 diabetes mellitus (Ludwig 2002) and associated chronic diseases. Diet and nutrition are the major environmental factors that may play pivotal role in onset of chronic diseases. Poor food intake consequently results in lower nutritional status (Jain et al. 2013a). Nutrition and health knowledge may influence dietary behavior that further becomes dietary patterns and influences individual’s nutrient intake (Jain et al. 2013b). Dietary modification is a primary preventive strategy for chronic illnesses. A diet having high fibre, low fat and low GI has been a corner stone of managing non communicable diseases. GI is a method of classifying foods based on the blood glucose response after food consumption. On a glycemic scale of 0 to 100, the GI compare carbohydrate weight for weight in individual foods providing a physiologic rather than structural basis for ranking glycemic potential (Onwulata et al. 2010). Rawa idli is a common snack frequently consumed by Indian population. Due to its general likeability and lack of information on its GI value directed the selection of this product for GI estimation. Soybean is an excellent source of dietary fibre, vegetable protein, complex carbohydrates, polyunsaturated fat, soluble fibres and phytoestrogens (isoflavons) that may be beneficial in prevention of hyperglycemia (Jenkins et al. 2003). It appears from several studies that soy based diets may provide benefits in conditions associated with impaired glucose tolerance, hyperlipidemia and reduce insulin sensitivity (Kang et al. 2006). Thus in present study an attempt was made to investigate the impact of addition of soyfibre, roasted soyflour and defatted soyflour on the sensory quality, nutrient content and glycemic index of rawa idli. Materials and Methods Formulation and standardization of rawa idli The various ideas and techniques of rawa idli preparation were recorded and screened. This stage led to taking up of various trials to prepare rawa idli keeping available carbohydrates as 50g. In preliminary trials wheat semolina and curd in different proportions were incorporated to standardize the products. Out of them, rawa idli was prepared from combination of 65g wheat semolina, 100g curd, 2g chemical leavener and 3.5g soybean oil was most acceptable. This product formed the foundation of remaining test products. The standardized recipes were (i) plain rawa idli [T1], (ii) rawa idli with Soyfibre [T2], (iii) rawa idli with roasted Soyflour [T3] and (iv) rawa idli with defatted Soyflour [T4] (table 1). Sensory evaluation A semi trained panel of 15 judges was selected using triangle difference test to conduct sensory evaluation. Nine point hedonic test and 5 point composite scoring test (Jellinek 1985) were used to study the organoleptic quality of standardized rawa idlis. Nutrition analysis Moisture, ash and crude fibre were determined (Raghuramula et al. 1983). Protein estimation was carried out by Biuret method and fat content was analysed by Bloor method. Determination of GI Study subjects Twelve healthy, non smoking, non alcohol consuming, female subjects were recruited. Informed consent from subjects was taken. Subjects were in the age group of 20 – 23 years had body mass index in the range of 18.5 – 25.0 kg/m2. Experimental procedures In first session, study subjects consumed reference food (R) (glucose dissolved in 200 ml of water). Than four test meals were given. Each test session was completed on a separate morning with at least 4 days interval between subsequent sessions. The test or reference meals were served at fixed