Browning is the second largest cause of quality loss in fruits and vegetables. It seems to be the most severe problem during banana pulp processing. Effect of two anti-browning pretreatments viz. addition of ascorbic acid (200-1200 ppm) and blanching the peeled fruits (90 0 C for different periods) prior to enzymatic clarification banana juice were studied. Effectiveness of anti-browning pretreatments to the pulp was evaluated by measuring the browning in terms of Browning Index in prepared clarified juices. Clarified banana juice obtained from untreated pulp had dark brown colour with initial browning index value of 0.411 which continuously increased and reached to 0.586 at 24 h of storage. Pretreatment of pulp with 1000 ppm of ascorbic acid or heating at 90 0 C for 6 minute was observed to retain the natural colour of prepared clarified juice without marked changes up to 4 h of storage at room temperature. However preheating of banana pulp observed to be caused cooked flavour and altered the original taste of the clarified juices.

Starch extracted from cassava was subjected to chemical and enzymatic modification. Extracted native starch and modified starches were evaluated for proximate analysis and then assessed for different functional properties such as water-binding capacity, swelling power and solubility. Chemically and enzymatic modified starches recorded higher waterbinding capacity i.e. 89.69% and 96.10% respectively and higher solubility 80.33% and 79.66% respectively as compared to native starch having the water-binding capacity 70.63% and solubility 25.18%. Scanning electron microscopy revealed round to polygonal in shapes with smooth surface for native starch and spherical to oval shaped granules for chemically modified starch. Enzymatic modified starch showed relatively rough surface, pores and cracks on surface fissures. X-ray diffractograms showed typical 'B' for pattern native starch but in modified starches showed typical 'A' pattern comparatively reduced peak and covers a larger area. FT-IR Image of starch and modified starch showed the typical peaks for the starch backbone. The O-H (alcohol) stretching band in the region 3500-3000 cm -1 was found to be broadened and became less sharp, strong and broad in the spectra of the native and chemical modified starch, in comparison to that of the enzyme modified starch. Functional properties of starch such as water-binding capacity and solubility of starch granules increased by chemical and enzymatic modification.

The effect of pectinase enzyme concentration (0.05 0.15%), incubation temperature (30-50''C) and incubation time (60-180 min) on juice yield, viscosity and clarity of banana juice were studied. A Central Composite Design was used to optimize the conditions for enzymatic clarification of banana pulp to maximize juice yield and clarity and to minimize pulp viscosity. Significant regression model describing the changes of juice yield, viscosity and clarity of juice with respect to hydrolysis paramètres were established with the coefficient of determination, R^ = 0.9881, 0.9951 and 0.9722 respectively. The recommended enzymatic clarification condition for the banana pulp of maturity stage 7 was 0.11% enzyme concentration at 39.8''C and incubation time of 143 min to achieve maximum juice yield (75.11%), clarity (94.05%) and minimum pulp viscosity (372 cps).

Aims: The aim of this study was to optimize clarification process of the Aloe vera juice followed by its preservation by ohmic heating as no systematic study has been conducted on these aspects. Study Design: The enzymatic clarification method was used for clarification of Aloe vera juice by using the enzyme pectinase. The enzyme concentration, incubation temperature and time were optimized for clarification of juice. The Aloe vera juice was treated at different Time (min) gradients, current, initial temperature and after temperature at particular current gradient and the ohmic heated juice was then stored in sterilized bottles for further analysis. Place and Duration of Study: Experiments were done in Department of Food Science and Technology, Shivaji University, Kolhapur, M.S. (India) and completed within 12 months. Methodology: The optimal conditions for the enzymatic treatment of Aloe vera juice were investigated in order to minimize the turbidity of the juice and maximize the TSS of the juice. The clarified Aloe vera juice was then treated with ohmic heating at different time and current combinations and stored for 60 days to study the physic-chemical and microbial parameters of stored juice. Results: The recommended enzymatic treatment conditions were: enzyme concentration 1% incubation time 6 h and incubation temperature 45ºC and the TSS, acidity and Turbidity under these conditions were 3.5ºBx, 0.30% and 206.66 NTU respectively. During storage, increased in TSS value from 2.1 to 2.6ºBx, acidity from 0.21 to 0.33% were recorded in ohmic treated juice samples. A very high TPC (102x105 CFU/ml) and yeast and mold count (68x105 CFU/ml) was recorded in untreated sample at 30 days of storage whereas the juice samples treated with ohmic heating at different time and current gradients were observed to be within the limit of standard requirement of microbial quality even up to 60 days of storage. Conclusion: Enzymatic treatments can reduce the turbidity in Aloe vera juice. Ohmic treatment at different time and current gradients can preserve the clarified juice with respect to its microbial quality for more than 60 days.

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