Optimization and quality assessment of ready-to-eat intermediate moisture compressed beetroot bar.

A ready-to-eat food product in the form of compressed bar from beetroot, enriched with dates and oats was developed. Levels of intermediate moisture beetroot shreds (60-100 g), dates (10-30 g) and oats (5-15 g) were optimized using response surface methodology and its quality attributes were investigated over a period of 6 months at different temperature conditions (ambient temperature; 22-32 and 37 °C). Optimum formulation for best beetroot bar consisted of beetroot shreds, dates and oat were derived as 71.8, 21.2, and 8.4 g, respectively. Developed product was found rich in fibers and minerals and recorded 38.4 mg/100 g betacyanains, 23.1 mg/100 g betaxanthins, 295 mg/100 g total phenolics (TP) and 160 mg/100 g total flavonoids (TF). The shelf stability studies of bar revealed predominant changes in bioactive compounds was caused by storage temperature. A loss of around 30, 15, 25, 31 and 32 % was observed for betacyanins, betaxanthins, TP, TF and radical scavenging activity, respectively during storage of 6 months at 6 °C compared to AT or 37 °C temperature conditions. The product had high overall sensory acceptability as well as microbial safety up to 6 months when stored at AT. The study indicated that beetroot could be effectively utilized into a novel shelf-stable ready-to-eat nutritious compressed product.

Moisture sorption characteristics of freeze dried whey-grape beverage mix.

Moisture sorption isotherms of freeze dried whey-grape beverage powder were determined at 20, 30 and 40 °C. A gravimetric static method was used under 0.11-0.85 water activity range and the sorption isotherms were found to be Type II. Various mathematical models were fitted to experimental data and it was found that Peleg model suits best in describing the equilibrium moisture content-equilibrium relative humidity relationships of instant whey-grape beverage mix over the range of temperatures studied. The net isosteric heat of sorption varied between 5.22 and 1.12 KJ/mol at moisture level varying between 1 and 9 % db. At moisture content below 1 % (db) the isosteric heat of sorption increased sharply for freeze dried whey-grape beverage powder and value of 49.08 KJ/mol was estimated.

Evaluation of sensory acceptability and storage stability of frozen carrot based dessert.

In the present study a recipe for frozen carrot based dessert (carrot halwa) was standardized on the basis of sensory characteristics such as appearance, odor, texture, taste and overall acceptability (OAA). The product was developed without addition of pure ghee to improve the storage stability under frozen conditions (-20 °C). Sensory properties of the developed product (OAA score = 8.60) were found to be equally good as compared to the conventional carrot halwa (OAA score = 8.75) which was prepared using pure ghee. From the physico-chemical analysis the developed product was found to have lower amount of fat (ca. 12%) than the conventional one. During the frozen storage, microbial growth in the product was found to be non-significant (P > 0.05). The free fatty acid content, peroxide value and thiobarbituric acid content increased during frozen storage of 15 months. But the increase was insignificant. Loss in total carotenoids content of the product was found to be 60.5% from initial value at the end of 15 months frozen storage.

Thermophysical properties of enzyme clarified Lime (Citrus aurantifolia L) juice at different moisture contents.

Thermophysical properties of enzyme clarified lime (Citrus aurantifolia L.) juice were evaluated at different moisture contents ranging from 30.37 % to 89.30 % (wet basis) corresponding to a water activity range of 0.835 to 0.979. The thermophysical properties evaluated were density, Newtonian viscosity, thermal conductivity, specific heat and thermal diffusivity. The investigation showed that density and Newtonian viscosity of enzyme clarified lime juice decreased significantly (p < 0.05) with increase in moisture content and water activity, whereas thermal conductivity and specific heat increased significantly (p < 0.05) with increase in moisture content and water activity and the thermal diffusivity increased marginally. Empirical mathematical models were established relating to thermophysical properties of enzyme clarified lime juice with moisture content/water activity employing regression analysis by the method of least square approximation. Results indicated the existence of strong correlation between thermophysical properties and moisture content/water activity of enzyme clarified lime juice, a significant (p < 0.0001) negative correlation between physical and thermal properties was observed.

Technology, applications and modelling of ohmic heating: a review.

Ohmic heating or Joule heating has immense potential for achieving rapid and uniform heating in foods, providing microbiologically safe and high quality foods. This review discusses the technology behind ohmic heating, the current applications and thermal modeling of the process. The success of ohmic heating depends on the rate of heat generation in the system, the electrical conductivity of the food, electrical field strength, residence time and the method by which the food flows through the system. Ohmic heating is appropriate for processing of particulate and protein rich foods. A vast amount of work is still necessary to understand food properties in order to refine system design and maximize performance of this technology in the field of packaged foods and space food product development. Various economic studies will also play an important role in understanding the overall cost and viability of commercial application of this technology in food processing. Some of the demerits of the technology are also discussed.

Kinetics of moisture loss and oil uptake during deep fat frying of Gethi (Dioscorea kamoonensis Kunth) strips.

Investigation was carried out to study kinetics of moisture loss, oil uptake and tristimulus colour during deep fat frying of Gethi (Dioscorea kamoonensis kunth) strips. Deep fat frying of Gethi strips of size 6 × 6 × 40 mm was carried out in a laboratory scale fryer at different temperatures ranging from 120 to 180 °C. The investigation showed that the moisture loss and oil uptake followed the first order kinetics equation (r > 0.95, p < 0.05). The kinetic coefficients for moisture loss and oil uptake increased significantly (p < 0.05) with temperature from 0.166 to 0.889 min(-1) and 0.139 to 0.430 min(-1) respectively. The temperature dependency of rate constants for moisture loss and oil uptake values was described using Arrhenius equation (r > 0.99, p < 0.01). The activation energies for moisture loss and oil uptake were found to be 41.53 KJ/mol and 27.12 KJ/mol respectively. The hunter colour parameters were significantly affected by frying temperature and frying time. The hunter lightness (L) value increased with respect to frying time initially, followed by decline and same trend was observed at higher temperatures of frying with elevated rate, whereas hunter redness (a) value increased significantly (p < 0.01) with time as well as temperature of frying and obeyed zero order rate equation. The temperature dependency kinetic coefficients of Hunter (a) value were described by Arrhenius equation and the energy of activation for change in hunter redness was found to be 42.41 KJ/mol (r > 0.99, p < 0.01). The other hunter colour parameters such as chroma, hue angle and total colour difference were markedly affected by frying temperature as well as frying time.

A refreshing beverage from mature coconut water blended with lemon juice.

Coconut water obtained from the mature coconuts was blended with lemon juice to develop a refreshing beverage. The levels of total soluble solids (°Brix) in the coconut beverage and lemon juice (%), were optimized using response surface methodology and considering pH, CIE L* value and sensory attributes (colour, aroma, taste, consistency and overall acceptability) as responses. A number total of 14 experiments were carried out following Central Composite Rotatable Design (CCRD) keeping 6 experiments at centre point. The data obtained were analyzed using multiple regression technique and the quadratic equations (R(2), 98.14-99.89 %) were found to fit well in describing the effect of variables on responses studied. An optimum condition for the coconut water beverage was obtained at 13.5°Brix blended with 2 % lemon juice. The mature coconut water beverage blended with lemon juice showed a shelf-life of 6 months in packed conditions at low (5 °C), ambient (25 ± 2 °C) and high (37 °C) temperatures on the basis of physicochemical, microbiological and sensory attributes.

Process optimization for osmo-dehydrated carambola (Averrhoa carambola L) slices and its storage studies.

An osmotic-dehydration process protocol for Carambola (Averrhoacarambola L.,), an exotic star shaped tropical fruit, was developed. The process was optimized using Response Surface Methodology (RSM) following Central Composite Rotatable Design (CCRD). The experimental variables selected for the optimization were soak solution concentration (°Brix), soaking temperature (°C) and soaking time (min) with 6 experiments at central point. The effect of process variables was studied on solid gain and water loss during osmotic dehydration process. The data obtained were analyzed employing multiple regression technique to generate suitable mathematical models. Quadratic models were found to fit well (R(2), 95.58 - 98.64 %) in describing the effect of variables on the responses studied. The optimized levels of the process variables were achieved at 70°Brix, 48 °C and 144 min for soak solution concentration, soaking temperature and soaking time, respectively. The predicted and experimental results at optimized levels of variables showed high correlation. The osmo-dehydrated product prepared at optimized conditions showed a shelf-life of 10, 8 and 6 months at 5 °C, ambient (30 ± 2 °C) and 37 °C, respectively.

Genetically modified foods: safety, risks and public concerns-a review.

Genetic modification is a special set of gene technology that alters the genetic machinery of such living organisms as animals, plants or microorganisms. Combining genes from different organisms is known as recombinant DNA technology and the resulting organism is said to be 'Genetically modified (GM)', 'Genetically engineered' or 'Transgenic'. The principal transgenic crops grown commercially in field are herbicide and insecticide resistant soybeans, corn, cotton and canola. Other crops grown commercially and/or field-tested are sweet potato resistant to a virus that could destroy most of the African harvest, rice with increased iron and vitamins that may alleviate chronic malnutrition in Asian countries and a variety of plants that are able to survive weather extremes. There are bananas that produce human vaccines against infectious diseases such as hepatitis B, fish that mature more quickly, fruit and nut trees that yield years earlier and plants that produce new plastics with unique properties. Technologies for genetically modifying foods offer dramatic promise for meeting some areas of greatest challenge for the 21st century. Like all new technologies, they also pose some risks, both known and unknown. Controversies and public concern surrounding GM foods and crops commonly focus on human and environmental safety, labelling and consumer choice, intellectual property rights, ethics, food security, poverty reduction and environmental conservation. With this new technology on gene manipulation what are the risks of "tampering with Mother Nature"?, what effects will this have on the environment?, what are the health concerns that consumers should be aware of? and is recombinant technology really beneficial? This review will also address some major concerns about the safety, environmental and ecological risks and health hazards involved with GM foods and recombinant technology.

Effect of bacoside extract from Bacopa monniera on physical fatigue induced by forced swimming.

The antifatigue effect of bacoside extract (BME) from Bacopa monniera (L.) Wettst. was investigated. Rats were subjected to weight-loaded forced swim test (WFST) every alternate day for 3 weeks. The BME at a dosage of 10 mg/kg body weight was administered orally to rats for 2 weeks in order to evaluate the following biomarkers of physical fatigue: swimming time, change in body weight, lipid peroxidation, lactic acid (LA), glycogen, antioxidant enzyme activities such as superoxide dismutase (SOD) and catalase (CAT) and blood parameters, namely blood urea nitrogen (BUN) and creatine kinase (CK). The exhaustive swimming time was increased by 3-fold in the BME supplemented group compared with that of the control group on day 13. The BME treatment lowered malondialdehyde (MDA) levels in brain, liver and muscle tissues by 11.2%, 16.2% and 37.7%, respectively, compared with the control exercised group (p < 0.05). The BME also reduced the LA, serum BUN and CK activities significantly compared with that of the control. Administration of BME significantly protected the depletion of SOD and CAT activities. The HSP-70 expression studies by western blot also confirmed the antifatigue property of BME. The present study thus indicates that BME ameliorates the various impairments associated with physical fatigue.

Specific identification of pathogenic Yersinia enterocolitica by monoclonal antibodies generated against recombinant attachment invasion locus (rAil) protein.

Classical pathogenic strains of Yersinia enterocolitica produce a 17 kDa outer membrane protein, Ail (attachment-invasion locus), which mediates bacterial attachment to some cultures epithelial cell lines and invasion of others. In the present study, hybridomas were developed for the production of monoclonal antibodies (MAbs) against Ail protein of Y. enterocolitica. A set of five stabilized hybridoma cell lines were generated, of which, two MAbs, YEA 302 and YEA 303, exhibited specific reaction to the native Ail protein (17 kDa) present in whole cell lysate of Y. enterocolitica strains beside having reaction with rAil. The other three MAbs, YEA 5, 17 and 32, had some cross reactions with proteins other than Ail. Two out of five MAbs were IgG1, two were IgG2b and one in IgM in nature. MAbs (YEA 302 and YEA 303) did not show any cross-reaction with whole cell lysate of Brucella abortus, Vibrio cholerae, Salmonella typhimurium and Escherichia coli and other species of Enterobacteriaceae including Y. pestis in ELISA and Western blot analysis. The presence of Ail protein among the strains recovered from pork and milk samples was evaluated by these sets of MAbs and the results were compared with the duplex PCR. Collectively, the data suggest that these MAbs may have the potential for their use in the detection of pathogenic Y. enterocolitica reliably, rapidly and at a relatively low cost.

Utilization of byproducts and waste materials from meat, poultry and fish processing industries: a review.

India is bestowed with vast livestock wealth and it is growing at the rate of 6% per annum. The contribution of livestock industry including poultry and fish is increasing substantially in GDP of country which accounts for >40% of total agricultural sector and >12% of GDP. This contribution would have been much greater had the animal by-products been also efficiently utilized. Efficient utilization of by-products has direct impact on the economy and environmental pollution of the country. Non-utilization or under utilization of by-products not only lead to loss of potential revenues but also lead to the added and increasing cost of disposal of these products. Non-utilization of animal by-products in a proper way may create major aesthetic and catastrophic health problems. Besides pollution and hazard aspects, in many cases meat, poultry and fish processing wastes have a potential for recycling raw materials or for conversion into useful products of higher value. Traditions, culture and religion are often important when a meat by-product is being utilized for food. Regulatory requirements are also important because many countries restrict the use of meat by-products for reasons of food safety and quality. By-products such as blood, liver, lung, kidney, brains, spleen and tripe has good nutritive value. Medicinal and pharmaceutical uses of by-product are also highlighted in this review. Waste products from the poultry processing and egg production industries must be efficiently dealt with as the growth of these industries depends largely on waste management. Treated fish waste has found many applications among with which the most important are animal feed, biodiesel/biogas, dietectic products (chitosan), natural pigments (after extraction) and cosmetics (collagen). Available information pertaining to the utilization of by-products and waste materials from meat, poultry and fish and their processing industries has been reviewed here.

Development of ready-to-fry frozen vegetable snack and its quality evaluation.

A formulation for the development of a crispy texture of crust in vegetable snack after freezing and frying was standardized using different flours such as whole-wheat flour (WWF), refined wheat flour (RWF), rice flour (RF) and semolina (S). Formulation with 60% WWF, 20% RWF, 10% RF and 10% S was selected based on sensory characteristics (overall acceptability >7.8). Incorporation of RF significantly (P < 0.05) changed the texture of the raw snack as indicated by texture profile analysis. Higher levels of rice flour resulted in whitish color in raw as well as fried snacks. However, the cooking time was more in the snacks fried directly from the frozen state (6.18 min) than the frozen-thawed fried snack (4.35 min). Quality of the snacks in terms of color values, appearance and texture was found to be superior to the thawed fried snack. During frozen storage of 16 months at -20 ± 1 °C, the overall acceptability (OAA) and lightness was found to be decreased from the original value. Rancidity parameters in terms of free fatty acids, peroxide value and thiobarbituric acid showed a restricted rise with the progression of storage period. The developed frozen snack was found to be microbiologically safe during the storage period.

Effect of ethanolic extract of clove on the keeping quality of fresh mutton during storage at ambient temperature (25 ± 2 °C).

Antimicrobial potential of ethanolic extract of clove (Eugenia caryophyllata) on fresh mutton during storage at 25 ± 2 °C was evaluated. The extract inhibited spoilage and pathogenic microflora of mutton previously treated with acidulants to reduce surface microbial load and the surface pH, up to 4 days without any deleterious change in sensory and physical qualities. Biomarker cadaverine, an indicator of spoiling/spoiled mutton, was present in 1 day stored control samples and absent up to 4 days in treated mutton. The levels of other biomarkers like biogenic amine index (0.31 mg/100 g) and free fatty acids (1.52%) were lower in 4 days stored treated samples than 1 day stored control samples (3.6 mg/100 g and 2.4%, respectively). Thus, ethanolic extract of clove can be effectively used to improve the keeping quality of fresh mutton up to 4 days at 25 ± 2 °C.

Development of ginger based ready-to-eat appetizers by response surface methodology.

Ginger is an herbaceous perennial rhizome traditionally used in culinary for its flavor and pungency. It is also used as carminative, stimulant and for its anti-emetic properties due to gingerols and shogaols. Appetite loss is one of the problems faced at high altitudes and the appetizers based on ginger may be useful for appetite stimulation. The fruit munch and ginger munch based on fresh and powdered ginger respectively were developed using response surface methodology (RSM). The sensory score, acidity and total sugars were the responses in the central composite designs of experiments with three independent variables. The ingredients raisins, dates, almonds were pre-processed by frying in stable fat while juice was extracted from pseudolemon and lemon. The optimized composition of ingredients was processed further through concentration. The carbohydrate rich munches had vitamin C content in the range 37-43mg/100g and calorific value of about 90kCal per munch. The munches packed in metalized polyester pouches had a shelf life of 8 months at ambient conditions (18-33 degrees C) as well as at a fixed temperature of 37 degrees C storage.

Effect of Aloe vera gel extract on antioxidant enzymes and azoxymethane-induced oxidative stress in rats.

The present work was undertaken with a view to study the effect of oral feeding of 2% Aloe vera gel extract (AGE) for 30 days on azoxymethane (AOM)-induced oxidative stress in rats. It was observed that AOM administration resulted in a significant increase in malondialdehyde and conjugated dienes, with reduction in hepatic glutathione (GSH), vitamin A and uric acid contents. AOM-induced reduction in hepatic GSH and uric acid was brought back to normal by AGE. There was a significant raise in hepatic catalase, superoxide dismutase and glucose-6-phosphate dehydrogenase (G-6-PD) activities as a result of feeding of the extract. Ingestion of the extract effected reduction in AOM-induced colonic GSH-peroxidase, G-6-PD and glutathione S-transferase and femur bone marrow micronuclei formation. Hence, it is suggested that Aloe vera gel extract possess the ability to reduce AOM- induced oxidative stress and toxicity in liver.

Simplification and optimization of deMan Rogosa Sharpe (MRS) medium for enhanced production of bacteriocin by Weissella paramesenteroides DFR-8.

Complex growth medium such as deMan Rogosa Sharpe (MRS) medium, commonly used for cultivation of fastidious lactic acid bacteria (LAB) interfere in bacteriocin purification. Sometimes all the ingredients of a defined medium are not required by all LAB strains for bacteriocin production. In the present study, composition of the MRS medium for the production of bacteriocin by Weissella paramesenteroides DFR-8, an isolate from cucumber (Cucumis sativus), was simplified and optimized with a step-wise strategy. In the first step, production profile, effect of incubation temperature, various C and N sources were investigated. In the second step, central composite rotatable design was employed to decide the optimal concentration of 3 key components (glucose, tryptone and pH) and the experimental results were fitted with a second order polynomial regression equation. According to the set criteria, the predicted bacteriocin titer from a medium containing 7.99% glucose, 9% tryptone, pH 7.5 (91.9% desirability) was 540 AU/ml and the observed bacteriocin titer was 538 AU/ml that indicated the validity of the developed model. Using optimized medium, bacteriocin titer of 674.5 AU/ml could be achieved after 72 h of fermentation that is nearly 2.5 fold higher than that obtained from unmodified MRS medium.

Effect of fiber incorporation on rheological and chapati making quality of wheat flour.

Traditional Indian unleavened bread (chapati) was prepared by incorporating wheat bran (insoluble fiber) and oat bran (soluble fiber) at different levels into whole wheat flour. Central composite rotatable design with 2 independent variables (wheat bran and oat bran) at 5 levels (wheat bran 3-9, oat bran 6-12%) was used to design the experiments. The flour samples containing different concentration of bran were analysed for pasting and mixing characteristics. Wheat bran had a negative (p ≤ 0.05) effect on peak viscosity, break down and final viscosity, whereas oat bran had a positive (p ≤ 0.05) effect on set back and final viscosity. Among mixing characteristics, the peak value was negatively affected (p ≤ 0.05) with increase in the level of both variables. Both variables had positive (p ≤ 0.05) effect on hardness of chapati while the cohesiveness, chewiness and overall acceptability scores were negatively affected. Based on compromise optimization, it is recommended to incorporate 5.5 g wheat bran and 9.7 g oat bran per 100 g flour for making optimally acceptable fiber rich chapati.

Quality of fried broiler chicken leg muscles stored at different temperatures.

Chicken leg pieces (60 g each). with optimized quantity of additives were fried in hydrogenated vegetable oil at 180°C for 8 min. The fried product was packed in paper-foil-polyethylene pouches (PFP) and stored under ambient (20 ± 5°C, 65-80% RH), refrigerator (5°C, 80% RH) and deep freezer (-18°C, 85-90% RH) conditions. The changes in microbial profile, oxidative and hydrolytic rancidity and sensory quality were evaluated periodically. It was found that the product was microbiologically (standard plate count (SPC) < 3 log cfu/g) safe and sensorily acceptable (overall acceptability >7) up to 4 days under ambient conditions. Hydrolytic and oxidative rancidity values during four days storage at room temperature were less than 0.16 % oleic acid and 3.5 mg malonaldehyde/kg, respectively. The products stored under refrigerated and deep freezer exhibited a shelf stability of 10 and 18 weeks, respectively. SPC was 1.3 log cfu/g while rancidity parameters were free fatty acid < 0.43% oleic acid and thiobarbituric acid reactive substances were <6.13 mg malonaldehyde/kg. Sensorily the product exhibited an overall acceptability score of >7 on a 9-point Hedonic scale during refrigerated and frozen storage.

Anti-inflammatory activity of Rhodiola rosea--"a second-generation adaptogen".

Rhodiola rosea (golden root), a unique phytoadaptogen grown in high-altitude regions has gained attention for its various therapeutic properties. In India, this plant is found in the Himalayan belt and has not been completely explored for its beneficial health effects. The present study was undertaken to evaluate the anti-inflammatory efficacy of the tincture extract of Rhodiola rosea roots (RTE). The anti-inflammatory activity was determined through carrageenan-induced paw oedema, formaldehyde-induced arthritis and nystatin-induced paw oedema in rat model. The tincture extract exhibited inhibitory effect against acute and subacute inflammation at a dose of 250 mg/kg body weight. Inhibition of nystatin-induced oedema was also observed in a dose-dependent manner. The in vitro inhibitory effects of the tincture extract from R. rosea roots was evaluated against the enzymes relating to inflammation. The enzymes include cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) and Phospholipase A2 (PLA2). The extract showed varying inhibitory activities against these enzymes depending on the concentrations. A potent inhibition was observed against Cox-2 and PLA2. Inhibition of nystatin induced oedema and phospholipase A2 suggested that membrane stabilization could be the most probable mechanism of action of RTE in anti-inflammation. The findings in this study may provide the use of R. rosea root extract in the treatment of inflammatory conditions.