Browsing by Author "Hariharan, G."

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    Drying of Green Mango Pulp: Effects of Processing Methods on Product Quality and Shelf Life
    (Uva Wellassa University of Sri Lanka, 2016) Mahendran, T.; Hariharan, G.; Krishnapillai, V.S.
    Mangoes (Mangifera indica L.) are consumed as ripe and unripe fresh fruit as well as various processed products. The processing not only adds value to the products, but also makes the products more convenient to the consumers. Green mango powder is used to add sour fruity flavor in stir-fried dishes, soups, curries and add the nutritional benefits of mangoes when the fresh fruit is out of season. The objective of this research was to define the methodologies for the processing of green mangoes into powder and to monitor the products after processing through physico-chemical, microbiological and sensory evaluation. Green mango (cv: Haden) powders were produced using tunnel drying, vacuum oven drying and spray drying and the quality characteristics were assessed in 2 weeks interval for a period of 3 months. The moisture content of the green mango powder ranged from 1.41 to 3.94% on dry weight basis. During drying, a significant reduction (p<0.05) in titratable acidity of 23% and increase in pH of 0.62 units after vacuum drying of mango indicated that some acids were lost due to evaporation during drying. The oxidative loss of ascorbic acid after vacuum drying was 24.1% which was higher than the tunnel drying (14.6%) and spray drying (7.2%) with 80% mango pulp + 20% maltodextrin additive. The maltodextrin formed a film around the mango solids that facilitated the production of non-hygroscopic and fine flowing powder. Microbiological studies revealed that there was no total plate count observed in the dried samples following storage. Ready-to-serve (RTS) green mango beverages were prepared from dried powders and were compared with those prepared from fresh mangoes.The sensory evaluation revealed that there were significant differences (P < 0.05)in colour, sweetness, flavour, consistency and overall acceptability between the treatments. Reduction in maltodextrin concentration improved the solubility of the mango powder, when 20% maltodextrin was added to mango pulp, the solubility of powder was 95% whereas adding 40% maltodextrin decreased the solubility to 86%. Based on the results, the spray drying is the best method for producing green mango powder with good nutritional quality and high storage stability. Keywords: Green mango powder, Maltodextrin, Nutritional quality, Sensory analysis, Spray drying.
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    Quality Attributes of Selected Ginger (Zingiber officinale) Varieties and their Potential to Formulatea Ready-To-Serve (RTS) Functional Beverage with Lime (Citrus aurantifolia)
    (Uva Wellassa University of Sri Lanka, 2016) Hariharan, G.; Mahendran, T.
    Nutritional enhancing, health promoting and disease preventing characteristics of functional beverages are thought to boon health against degenerative diseases. Incorporation of phyto-chemicals to formulate Ready-To-Serve (RTS) functional beverage is one of the ways of value addition since the ingredients have functional properties. An experiment was conducted to select the superior ginger variety among the available ginger varieties such as Local, Chinese and Rangoon for formulation of RTS functional beverage and to select the most suitable blending ratio of ginger juice and lime juice. Different blends were prepared by mixing various proportions of ginger juice extract from 10 to 20% and lime juice extract from 2 to 10% sweetened by Palmyra sugar candy. Average weight of rhizomes was higher in Chinese variety (46.81g) than Rangoon (35.23g) and Local (27.56g) varieties. The juice percentage of Chinese variety was comparatively higher (88.39%) than Rangoon (73.24%) and Local (61.52%) varieties. Ginger juice extract of Local ginger variety had a higher mean score for Total Soluble Solids (2.81°Brix) than Rangoon (2.54°Brix) and Chinese (2.32°Brix) varieties. On a 7-point hedonic scale, Local variety was found to be superior in sensory scores for colour (5.7), aroma (5.6) and overall acceptability (5.7). Chinese ginger variety had a higher mean score for pungency (4.2) compared to other tested varieties. The results indicated that Local variety was superior to Chinese and Rangoon varieties to formulate RTS beverages. Freshly made formulations showed a gradual increase in titratable acidity from 0.22 to 0.52% (as % of citric acid), Total Soluble Solids from 12.6 to 16.8°Brix, ascorbic acid from 12.4 to 56.9 mg/100 ml and total sugar from 16.6 to 20.39% and gradual decrease in pH from 6.63 to 3.11 with increase in lime juice extract from 2 to 10%. It was concluded that functional beverage with 12% of ginger juice and 8% lime juice, sweetened by Palmyra sugar candy was the best formulation and could be stored at 30±1°C temperature and 70-75% of RH for a period of 12 weeks without any significant variations in quality attributes. Keywords: Functional beverage, Ginger, Lime, Palmyra sugar candy, Phyto-chemicals
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    A Study to Enhance the Shelf Life and Postharvest Quality of Tomato (Solanum lycopersicum L.) using Aloe Vera Herbal Coating
    (Uva Wellassa University of Sri Lanka, 2018) Mahendran, T.; Hariharan, G.
    Tomatoes have limited marketability owing to its high moisture content and high degree of perishability which leads to extensive postharvest losses. It is estimated that 40-60% of the harvested tomatoes go waste annually. There has been increased usage of Aloe vera gel as a herbal coating for fruits owing to its antimicrobial properties. In this study, the effectiveness of Aloe vera gel coating on the shelf life and quality of tomatoes were investigated. The mature green tomatoes were dipped in the concentrations of 1, 2, 3 and 4% (w/v) Aloe vera gel solutions for 5 min and air-dried for 24 hrs. The coated fruits were stored at 30°C and 90% RH for 30 days along with the uncoated controls. The nutritional properties, sensory acceptance and microbiological studies were carried out for all the treatments. Herbal coating significantly enhanced the firmness and reduced weight loss, delayed changes on total soluble solids and retarded the loss of total acidity compared with uncoated tomatoes. Fruits coated with 2% of Aloe vera gel showed greater retention of ascorbic acid, titratable acidity and total sugars of 11.26 mg%, 0.53% and 12.5% respectively, following 28 days of storage at 30°C. Sensory evaluation was done using 30-trained panelists and the results revealed that the use of the Aloe vera gel coating increased the acceptability of tomatoes. The determining factor of shelf life of tomatoes was the microbial spoilage. The Aloe vera gel coated tomatoes showed reduced number of microbial growth than that of control. The shelf life of tomatoes coated with 1 and 2% of Aloe vera gel increased up to 21 and 28 days respectively, without decay while tomatoes coated with 3 and 4% Aloe vera gel solution showed lower shelf life of 20 and 12 days respectively, with higher percentage decay. The control tomatoes decayed at the end of the 10th day of storage. Therefore, Aloe vera gel solution of 2% could be used as an edible herbal coating to enhance of shelf life of tomatoes.