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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.

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.

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Quality determines the shelf life as well as selling price of fresh fruit or vegetable and therefore, quality monitoring and testing of fresh commodities have paramount importance in their postharvest handling and supply chain management. Most of the methods used to assess fruits and vegetables quality are destructive in nature. Nowa-days, various mechanical, optical, electromagnetic, and dynamic non-destructive methods are gaining importance due to ease in operations, faster turn over and reliability. Some of the non-destructive techniques (NDT) are currently being used in laboratories, research institutions and food packaging and processing industries, whereas, some methods are still at developmental stage. Various NDT with respect to their principle and applications such as impact test, electronic nose, time-resolved reflectance spectrometry, near infrared spectroscopy, nuclear magnetic resonance, X-Ray, ultra sonic, acoustic impulse response method, electrical conductivity methods etc., are discussed in this review.