Post Harvest Techniques and Utilization of Some Fishes and Small Prawns with Market Study

Abstract

The study was carried out during July 2009 to June 2015. The studied fish species (Labeo rohita, Cirrhinus mrigala, Hypophthalmichthys molitrix, Puntius sophore and Small prawns) were collected from five fish markets such as Shaheb bazar fish market, Binodpur fish market, Shalbagan fish market, Laxmipur fish market and Court bazar fish market of city corporation area, Rajshahi, Bangladesh and brought in to the Laboratory of Department of Fisheries, University of Rajshahi, Bangladesh for processing, preservation and utilization. After processing, the prepared fish powder were brought into the laboratory of Bangladesh Council for Scientific and Industrial Research (BCSIR), Rajshahi, Bangladesh, Central Science Laboratory and Institute of Biological Sciences, University of Rajshahi, Bangladesh, for the determination of biochemical compositions and shelf life assessment. The highest after dressing and washing weight was 920.5g (small prawns) and lowest was 728.9g (H. molitrix). After dressing and washing waste was found highest in H. molitrix (271.1g) and lowest was found in small prawns (79.5g). The lowest landing of the studied species was observed 40kg/day (Court bazar) and highest was 500 kg/day (Shaheb bazar). The average price of the fishes and small prawns varied from BDT. 61.3 (H. molitrix) to 260/kg (P. sophore). Different types of snacks items were prepared including fish powder such as, fish khoi cake, fish vegetable cake, fish luci and vegetable, fish saaz pitha, sweet fish cake, fish spicy cake, fish kabab shashlik and papadom. The highest production cost was found BDT. 2212 (Shashlik in Small prawns) and lowest was BDT. 246 (Fish luci in H. molitrix). The cost benefit ratio was lowest 0: 0.26(Fish vegetable cake in L. rohita) and highest 0: 2.49 (Fish papadom in H. molitrix). The appearance, odour, colour, test, texture, flavour and overall acceptability of the fortified snacks items were good and excellent. The lowest protein content of fish powder was found 54.31% (P. sophore) and highest was 68.50% (Small prawns). The lowest lipid content was observed 13.33% (P. sophore) and highest was 19.33% (L. rohita). The moisture content varied from 11.55% (L. rohita) to 13.95% (H. molitrix) and the ash content varied from 0.16% (Small prawns) to 0.44% (C. mrigala). The lowest carbohydrate content was found 1.75g/kg (L. rohita) and highest was 19.23g/kg (P. sophore). Among the minerals contents phosphorus, calcium and iron content varied from 0.95g/kg (L. rohita) to 1.91g/kg (P. sophore), 2.49g/kg (L. rohita) to 2.55g/kg (Small prawns) and 0.43g/kg (H. molitrix and P. sophore) to 1.85g/kg (C. mrigala), respectively. In normal room temperature, total bacterial load varied from 1.5×102 (Small prawns) to 4.4×107 CFU/g (P. sophore) and the TVB-N values varied from 4.18 (Small prawns) to 36.65 mg N/100g (P. sophore). In refrigerated temperature, TVB-N values varied from 0.16 (Small prawns) to 0.74 mg N/100g (L. rohita) and no microbes were observed in fish powder in the present study.