Effect of yeast on functional and rheological characteristics of whole wheat flour and its effect on quality of chapati.

Chapati is unleavened flat bread originated from Indian sub-continent and is considered as staple product in everyday meals. Its quality attributes are dependent on number of factors including the wheat used, ingredients added and processing parameters. The study was aimed to observe the effect of yeast addition on functional, rheological, and sensory characteristics on whole wheat flour and chapati at varying percentage (0.25-1.0). All the experiments conducted were compared with a control flour/chapati without yeast addition. The results showed that all the attributes were favourably affected with yeast addition when compared with control samples. It was noticed that the peak viscosity, setback, breakdown and final viscosity decreased with yeast addition and the paste obtained had higher gel strength. Alveogragh results also depict the increase in tensile strength and decrease in extensibility of dough on yeast incorporation. Textural and sensory studies revealed that yeast concentration upto 0.75% w/w in whole wheat flour resulted in chapati with good overall acceptability.

Ranking based formula optimization, quality investigation, and real-time shelf-life prediction of ready-to-eat ricebean (Vigna umbellata) curry.

Ricebean (Vigna umbellata) is an underutilized bean of South and South-East Asia, was exploited to formulate the ready-to-eat curry by using thermal processing technology. Eleven types of RTE ricebean curries (RBCs) namely RBC1, RBC2, RBC3, RBC4, RBC5, RBC6, RBC7, RBC8, RBC9, RBC10, RBC11 were developed by varying the proportion of tomato paste, onion paste, and coriander powder after thermal processing at 121 °C (15 psi) for 20 min. Out of these, the best quality curry was selected based on the total product ranking score (TPRS) which was calculated from the curry quality parameters such as consistency, pH, loss due to sorption onto the inner surface of the retort pouch (LOSS), and sensory (overall acceptability-OAA). Among the curries, RBC2 secured the highest value of TPRS, named it as RTE-RBC and was used to study the physico-chemical, textural, nutritional, microbial, sensory parameters and storage stability. The DPPH-antioxidant activity of RTE-RBC was 2.47 µM BHA/g which was due to the presence of bioactive phytochemicals such as polyphenol, flavonoids, lycopene, gingerol, É£-Oryzanol, and capsaicin. It was observed that the in-vitro protein/carbohydrate digestibility, in-vitro calcium bioavailability and real-time shelf-life (predicted) of RTE-RBC were 85%, 54%, and one year, respectively.

Effect of vacuum and atmospheric frying and heating on physico-chemical properties of rice bran oil.

The study highlights the impact of vacuum (13.33 kPa) and atmospheric (101.325 kPa) pressure on the Physico-chemical stability of rice bran oil (RBO) during continuous frying and heating at equivalent thermal driving force (∆T = 45 °C). Reduced operating pressure played a major role in retaining the Physico-chemical quality of RBO. Results show that the PV, FFA, p-An value, IV, TOTOX value, total polar compound (TPC), saturated fatty acids, CIE color values, and viscosity of RBO increased significantly (p < 0.05) at a higher rate during frying and heating (22.24 h) under atmospheric pressure as compared to vacuum pressure. TPC and total saturated fatty acids were formed 34.37% and 32.76%, and 7.33% and 2.23% more, respectively, whereas, total unsaturated fatty acids were found to be 3.34% and 1.04% less during frying and heating at atmospheric pressure as compared to vacuum pressure condition. In general, vacuum frying technology is suitable for making papaya chips with extended reuse of RBO.

Optimization of instant foxtail millet based khichdi by using response surface methodology and evaluation of its shelf stability.

Instant foods are a great convenience in today's fast moving world, aiding to reduce the time spent on the cooking process, along with the added advantage of long shelf life and ease to carry. Ingredient composition was finalized by optimizing the design variables (instantised foxtail millet, instantised green gram dal and oat flakes) using Central Composite Rotatable Design besides suitable fat and spices for the development of instant foxtail millet khichdi. Over all acceptability and water holding capacity were considered as the responses for the experimental design. The developed quick cooking (jiffy) product possessed calorific value of 525.11 kcal/100 g with good rehydration/ reconstitution properties within 4 min. Shelf stability of the khichdi packed in polypropylene (75µ) and metallised polyester (90µ) pouches was evaluated in terms of chemical, microbiological and sensorial changes. The product was found to be shelf stable for 6 months of storage in metallised polyester.

Influence of cooking methods on antinutritional factors, oligosaccharides and protein quality of underutilized legume Macrotyloma uniflorum.

Macrotyloma uniflorum is a salubrious but underutilized legume mainly consumed in semi-arid zones of Africa, Australia and India. Various antinutritional factors- phytates, oxalates and oligosaccharides- has limited its consumption. Current work describes the influence of various thermal processing technologies - autoclaving, microwave, micronization and extrusion- on antinutritional profile, phenolic acid profile and protein digestibility of two selected varieties. Significant (p ≤ 0.05) reduction in antinutritional content was observed for horse gram grains processed using various thermal technologies. Among all processing technologies extrusion caused marked degradation in antinutritional components. The reduction in oxalic acid, trypsin inhibitor, phytates and tannins ranged from 33 to 87 %, 77-82%, 33-60% and 51-66% respectively. Further, the decline in content of various oligosaccharides viz. raffinose, stachyose and verbascose varied from 36 to 61 %, 25-49% and 30-74% respectively for both the varieties. Although extrusion caused significant (p ≤ 0.05) decrease in the essential amino acid index and protein efficiency ratio, simultaneous increased was observed in biological value. The processing had significant (p ≤ 0.05) impact on grain antinutritional content and also retained its substantial functional properties. This establishes the utility of grain and promote the introduction of these new grains and enlarge the market of novel healthy foods.

Influence of processing methodology on phenolic acid content, fatty acid profile and oxidative stability of Macrotyloma uniflorum.

Study was conducted to determine the influence of different cooking methods namely pressure, flaking, infra-red, microwave and extrusion processing on rate of oxidative stability, fatty acid profile and functional properties of horse gram. The rate of auto-oxidation was significantly (p < 0.05) affected during storage and found maximum at 0.00 aw and minimum at 0.33 aw for both varieties namely GPM-6 and PAIYUR-2. The extrusion processed grains were more susceptible to auto-oxidation. The iron content of grain increased significantly (p < 0.05) during extrusion (1.22 ± 0.50 to 1.65 ± 0.15 mg 100 g-1 for PAIYUR-2 and 1.19 ± 0.45 to 1.59 ± 0.12 mg 100 g-1 for GPM-6). Whereas, tocopherol content decreased during extrusion (8.05 ± 0.15 to 2.28 ± 0.23 mg 100 g-1 for PAIYUR-2 and 6.48 ± 0.46 to 1.68 ± 0.15 mg 100 g-1 for GPM-6). Ellagic (12.36 ± 0.35 and 10.71 ± 0.29 mg 100 g-1), vanillic (15.20 ± 0.23 and 12.48 ± 0.18 mg 100 g-1), and coumaric acid (14.68 ± 0.71 and 8.97 ± 0.66 mg 100 g-1) were the major phenolic acids whereas, linoleic (35.53 ± 0.30 and 35.46 ± 0.19%), palmitic (26.08 ± 0.26 and 25.97 ± 0.33%), and linolenic acid (13.44 ± 0.18 and 10.13 ± 0.21%) were the major fatty acids present in raw grain for PAIYUR-2 and GPM-6 respectively. Phenolic and fatty acids were significantly (p < 0.05) affected during processing. The oxidative stability of microwave processed grains was maximum whereas, extrusion processed grains showed minimum oxidative stability during storage. Study explicitly describes that native grains and the grains which did not undergo destruction of naturally present cellular structure, were less prone to oxidation. The oxidation rate of grains was found dependent on composition, processing and storage environment of grains. Hence, all these factors need to be considered to ensure the stability of processed food during storage.

Development of multigrain premixes-its effect on rheological, textural and micro-structural characteristics of dough and quality of biscuits.

Four different Multigrain Premixes (MGPs) namely MGP I, MGP II, MGP III, MGP IV were developed to select the best premix for preparation of biscuits based on nutritional value and biscuit quality. The MGPs were prepared using cereals (barley, sorghum, maize, oats), pulses (chickpea dhal, green gram, peas, soya flour), millets (pearl millet, finger millet) and wheat germ each at 20 % level. The MGPs developed had 22.91-27.84 % protein, 16.82-18.72 % dietary fiber and 3.11-3.46 % minerals. The wheat flour was replaced with MGPs separately at different levels of 10, 20, 30, 40 and 50 %. The incorporation of these MGPs significantly (p ≤ 0.05) decreased the water absorption (56.0-50.9 %), peak viscosity (273.67-154.92 RVU), biscuit spread ratio (10.28-8.15) and increased the pasting temperature (67.10-79.20 °C), dough hardness (311.66-460.26 N) and biscuit breaking strength (13.25-28.68 N). SEM studies showed that incorporation of MGP disrupted the protein matrix. Among the MGPs, MGP III was found to be more suitable even at the 40 % level for obtaining nutritious multigrain biscuits with higher protein, dietary fiber, and mineral content.

Optimization of barrel temperature and kidney bean flour percentage based on various physical properties of extruded snacks.

The aim of the experiment was to optimize barrel temperature (122 to 178 ± 0.5 °C) and red kidney bean flour percentage (KBF) (12 to 68 ± 0.5 %) based on physical properties of extrudates like flash off percentage, water absorption index (WAI), water solubility index (WSI), bulk density (BD), radial expansion ratio (RER) and overall acceptability (OAA) using single screw extruder. The study was carried out by central composite rotatable design (CCRD) using Response surface methodology (RSM) and moisture content of feed was kept as constant 16.0 ± 0.5 % throughout experiments. Mathematical models for various responses were found to fit significantly (P < 0.05) for prediction. Optimization of experimental conditions was carried out using numerical optimization technique and the optimum barrel temperature and kidney bean flour percentage were 120 °C (T1) & 142.62 °C (T2 = T3) and 20 % respectively with desirability value of 0.909. Experiments were carried out using predicted values and verified using t-test and coefficient of variation percentage. Extruded snack prepared with rice flour (80 %) and kidney bean flour (20 %) at optimized conditions was accepted by the taste panellists and above 20 % KB incorporation was found to decrease overall acceptability score.