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The present study entitled “Development of Aloe vera gel supplemented Ready To Serve fruit beverages” was carried out in the Department of Processing Technology, College of Agriculture, Vellayani during 2014-2016 with the objective to optimize the process variables for osmotic dehydration of aloe gel, supplementation of aloe gel in Ready To Serve (RTS) fruit beverages and to evaluate the quality of the product during storage.
Aloe vera leaves of uniform size, free from pests, diseases and mechanical damages were subjected to blanching treatments viz., steam blanch, hot water blanch and without any blanching. Aloe gel extracted by traditional hand filleting method was analyzed for biochemical, physical and sensory quality parameters.
Blanching treatments did not influence TSS, pH, crude fibre and ash content of aloe gel. Aloe gel extracted after steam blanching recorded the lowest moisture content (92.58%), highest acidity (0.17%), antioxidant activity (81.30%), total phenol (40.98 µg g-1), reducing sugar (0.43%) and total sugar (0.53%). On analyzing the physical properties, highest viscosity (9.98cP at 60 rpm) and lowest optical density (0.805) were recorded for steam blanched aloe gel in addition to highest mean score for sensory attributes. Steam blanched aloe gel had a refractive index of 1.3366 and specific gravity of 1.0200 and was selected for osmo dehydration studies.
Aloe gel of 1cm3 cube size taken after steam blanching was osmosed in sugar syrup of 30, 40 and 500B concentrations with an immersion time of four and six hour. The osmo dehydrated aloe gel was analyzed for mass transfer, biochemical, physical and sensory qualities. Mass transfer characters viz., solid gain and weight loss and biochemical parameters such as total soluble solids, reducing sugar and total sugar increased with increase in osmotic concentration and immersion time and it did not influence pH, acidity and ascorbic acid of aloe gel. Osmotic treatment of aloe gel at 500B for four hour immersion time recorded 9.72% solid gain with 58.81% weight loss, 60.52% moisture, 41.030B TSS, 7.59 µg g-1 phenol, 75.95% antioxidant activity, 2.97% reducing sugar, 14.92% total sugar, 1.4033 refractive index, specific gravity of 1.0848, optical density of 1.442 with highest sensory score for flavour, taste and texture and hence selected to formulate aloe gel supplemented RTS fruit beverages.
Osmo dehydrated aloe gel (in 500B syrup concentration for four hour) at 5 % and 10 % level and total aloe juice (5%) were supplemented into Ready To Serve beverages of pineapple, lime and cashew apple. Formulated beverages were analyzed for biochemical and sensory properties and compared with respective fruit RTS without aloe gel supplementation. Analyses revealed that 10% supplementation resulted in RTS beverages with superior biochemical and sensory qualities and hence pineapple, lime and cashew apple RTS supplemented with 10% osmo dehydrated aloe gel were subjected to storage stability studies under room temperature for three months.
The stored RTS formulations were analyzed for biochemical, sensory and microbial qualities at fortnight intervals. During storage, total soluble solids, reducing sugar, total sugar and acidity of all aloe gel supplemented RTS beverages increased while pH, ascorbic acid, antioxidant activity and total phenol content decreased. Sensory profile of stored aloe gel supplemented RTS beverages revealed that they were acceptable during storage of three months with slight reduction in sensory scores. All RTS beverages were found microbiologically safe during storage and aloe gel supplemented lime RTS formulation recorded the highest acceptability.