TITLE:
Influence of Bleaching Powder on the Quality of Giant Freshwater Prawn (Macrobrachium rosenbergii)
AUTHORS:
Md. Mizanur Rahman, Md. Shaheed Reza, Mohammed Nurul Absar Khan, Golam Mohammad Moshiur Rahman, Md. Nazrul Islam, Md. Kamal
KEYWORDS:
Bleaching Powder; Myofibrillar Protein Solubility; Giant Freshwater Prawn; Organoleptic Quality
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.4 No.9B,
August
21,
2013
ABSTRACT: Calcium hypochlorite commercially known as bleaching powder is used as a bleaching agent in shrimp processing industries in many countries and known to effect biochemical alteration in shrimp muscle. Studies were, therefore, undertaken to determine their effect in different concentrations viz., 10, 20, 30, 40 and 50 ppm with different time intervals on the quality of head-on, headless shell-on and peeled giant freshwater prawn (Macrobrachium rosenbergii) by determining biochemical and organoleptic aspects. Myofibrillar protein solubility of fresh head-on, headless shell-on and peeled samples were 90.5%, 90% and 88%, respectively indicating a gradual decrease in protein solubility with increasing concentration of bleaching powder. Decrease in protein solubility was also higher in samples kept at longer duration in different concentration of bleaching powder. At a given concentration of 50 ppm for 30 min treatment, the loss of myofibrillar protein was higher (26.14%) in peeled samples than those of head-on and headless shell-on samples (20.44% and 21.11%). Shelf life of bleaching powder treated prawn samples was found to be reduced to 4 - 5 days in iced condition compared to 6 - 7 days for control samples. Peeled samples were also found to be more susceptible to bleaching powder than that of head-on and headless shell-on samples.