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Subject: Food Science and Technology × Author: Hailemariam Tekie × End date: 2009 × Start date: 2009 ×
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    ThesisItemOpen Access
    Fresh keeping of cut-watermelon (Citrullus lanatus mansf.) by hurdle technology
    (CCSHAU, 2009) Hailemariam Tekie; Siddiqui, Saleem
    The present investigation has been done to enhance the shelf life of fresh cut watermelons by use of natural antimicrobials applied through hurdle technology. Watermelon fruits were collected from the local market and the samples (cut-watermelons) prepared were subjected to different treatments (1000ppm vanillin, 1500ppm vanillin, 10min UV-C light, 20min UV-C light, 10% honey, 15% honey, and 1000ppm vanillin + 10min UV-C light + 10% honey combined treatments). The treated samples were packed in a specially designed package and finally stored at a temperature of 100C till the day of analysis. The analysis was performed on every alternate day for various physico-chemical, microbial and sensory characteristics. Storage had significant effect on the different quality parameters of cut-watermelon. Texture, pH, vitamin C and microbial quality decreased, whereas, titratable acidity, juice leakage, phenolic content, and carotenoid content increased during the storage period. The different treatments had significant effect on the quality of cut-watermelon. UV-C light treatment resulted in reduced microbial load, increased phenolic content, reduced drip losses, & maintained the texture. However, it caused reduced TSS, reducing & total sugars, and vitamin C content. UV-C (20 min) was found to be more effective than UV-C (10 min) treatment in maintaining the microbial quality of cut-watermelon. Honey showed improved storage potential with respect to most of the chemical parameters which were not maintained by UV-C treatment as well as coliform count. Honey (15%) was more effective 10% honey treatment. However, honey at both its concentration did not show reduced yeast & mold count and total plate count. Vanillin (1500ppm) showed improved microbial quality (yeast & mold count and total plate count), texture, and carotenoid content. However, vanillin (1000ppm) generally did not significantly affect most of the physico-chemical parameters studied. Sensory characteristics of cut-watermelon was affected by storage periods which showed increased acceptability up to the 3rd day in all the sensory attributes and decreased thereafter, but it was not significantly affected by the different treatments used in the present study. The results obtained in the present investigation indicated that there was no individual treatment that could exclusively improve all the quality parameters and enhance the shelf life of fresh cut-watermelon. The combined V + U + H hurdle treatment did not show additional advantage over the individual treatments in most of the quality parameters and shelf life of fresh cut-watermelon.