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Shellac (S) and Aloe vera gel (AG) were used to develop edible surface coatings for shelf-life extension of tomato fruits. The coating was prepared by dissolving dewaxed and bleached shellac in an alkaline aqueous medium as such as well as in combination with AG.

Beetroot juice contains a high level of biologically accessible antioxidants, beneficial phytochemicals and dietary nitrate, which seem to exert beneficial effects in human health. Dietary nitrate, from beetroot has been reported to lower blood pressure. However the impact of beetroot on lipid profile and oxidative stress is unknown. In present study, the effect of supplementation with beetroot juice for 15 days was investigated. Plasma lipid profile, antioxidant status, oxidative stress and body composition changes were evaluated at baseline and after 15 days of beetroot juice supplementation. Beetroot juice supplementation beneficially influenced the lipid profile by significantly increasing the levels of high-density lipoprotein cholesterol (HDL-C) from 42.9 ± 8.3 mg/dl to 50.2 ± 9.8 mg/dl and decreasing lowdensity lipoprotein cholesterol (LDL-C) from 129.7 ± 82.3 mg/dl to 119.5 ± 79.2 mg/dl compared with baseline values. Beetroot juice supplementation increased (P < 0.05) plasma nitrite level and guanosine 3', 5'-cyclic monophosphate (c-GMP) levels. A significant increase in plasma total antioxidant capacity and vitamin C levels was observed after beetroot juice intake for 15 days. There was no significant change in the body fat mass and lean body mass of participants with the beetroot juice supplementation. Beetroot juice supplementation significantly decreased the stress markers plasma hydroperoxides and cortisol levels. Beetroot juice acts as a potent vasodilator by increasing plasma c-GMP levels and nitrite levels. Beetroot juice consumption improves plasma lipid profile and antioxidant status, encouraging further evaluation on a population with higher cardiovascular disease risk.

Efficacy of variable high pressure, temperature and time on the browning causing enzymes and microbial activities, which are major spoilage factors during preservation of sugarcane juice, was studied. The juice was processed at 200-600 MPa pressure for 2-8 min at 40 and 60 °C and their effect on polyphenol oxidase and peroxidase as well as microbiological quality in terms of total plate count, yeast and molds and total coliforms was studied. Application of high pressures were found to cause significant decrease in enzymatic and microbial activities. The effects were found to be significantly more pronounced at 60 °C as compared to 40 °C. Process time also caused significant ( < 0.05) negative effect on microbial and enzyme activities. The sugarcane juice treated at 600 MPa for 6 min at 60 °C was found sufficient to inactivate the microbial counts completely. Whereas, enzymes were found to be completely inactivated in the samples processed at 600 MPa for 8 min at 60 °C. A pressure of 600 MPa at 60 °C for 8 min could be applied during commercial preservation of sugarcane juice for getting complete inactivation of browning causing enzymes and spoilage causing microorganisms.

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.

The effect of high pressure processing on total antioxidant activity, phenolic and flavonoid content of black grapes juice was studied. Response surface methodology (RSM) was used for designing the experiment keeping high pressure (400-600 MPa), temperature (40-60°C) and processing time (2-4 min) as independent variables. The data obtained were analysed using multiple regression technique and quadratic models were found to fit well (R 2 , 85.61-96.65%) in describing the effect of high pressure, temperature and time on total antioxidant activity, phenolics and flavonoids. The optimum levels were found to be 550 MPa, 44°C and 2 min for pressure, temperature and processing time, respectively (desirability, 95.00) for getting the maximum retention of total antioxidant activity, phenolics and flavonoids in the juice. The experimental and predicted valued of responses showed high correlation (R 2 , 99.26-99.90%) at the optimised levels of the variables.

Jam like product was prepared using high pressure (HP) processing technology and was compared with thermally processed one for quality attributes. Strawberry pulp was mixed with pectin (1%) and sugar and packed in low density polyethylene pouches (50 g pack size) and processed at 200, 400 and 600 MPa for 30 min at 50 °C. Ascorbic acid, anthocyanins, phenolics, flavonoids and antioxidant activities were found to be significantly retained to a better extent in HP processed jams as compared to thermally processed one. The CIE *,* and * values decreased significantly with increase in pressure, the decrease being of much lesser extent compared to thermally processed one. Increase in pressure was found to increase the sensory attributes for colour, appearance, flavour, texture and overall acceptability significantly; however, the scores were comparatively lesser than that of thermally processed jam. The sample processed at 600 MPa showed a shelf-life of 3 months on the basis of physico-chemical, sensory and microbial attributes when stored at ambient storage conditions (28 ± 5 °C).

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