Characteristics of freeze-dried fish protein isolated from saithe (Pollachius virens)

Abstract

Fish proteins isolated from by-products or low commercial/underutilized species using pH-shift process is a new source of proteins that may be used as wet or dried ingredients to develop value-added convenience foods. This paper reports the effects of freeze-drying on characteristics of fish protein isolates (FPI) from saithe (Pollachius virens) with or without lyoprotectants. Freeze-dried saithe mince from the same lot and without additives was used as a control. The resulting fish protein powders contained 71-93% protein, 1.5-3% moisture, 0-21% carbohydrate and 0.5-2% fat. Lipid oxidation (assessed by TBARS) of FPI powder groups was higher than that of fish mince powder. The results revealed that oxidation started during the pHshift process and was increased by freeze-drying. Functional properties and sensory attributes were influenced by the advanced oxidation. However, the mince powder was less oxidized and had higher functional properties such as water binding capacity, gel forming ability, emulsification, foaming properties and colour and lower sensory scores for rancid odour and flavour than the FPI powders. Further studies on how to prevent oxidation of fish flesh during pHshift and drying processes are recommended.

Development of fish protein powder as an ingredient for food applications: a review

“…Figure 2 illustrates surimi processing stages. Sathivel et al 2004;Shaviklo et al 2010aShaviklo et al , 2012 The raw materials used for extracting myofibrillar proteins should be fresh and kept chilled. Fish flesh is separated from fish fillets by a fish bone separator (Min et al 1988).…”

“…Therefore, proteins must be stabilized against both of these fundamentally different stresses (Crowe et al 1990;. Lyoprotectants including saccharides, amino acids and sugar alcohols are used to stabilise the proteins during the freeze drying process (Arakawa et al 2001;Carvajal et al 2005;Shaviklo et al 2011aShaviklo et al , 2012Huda et al 2012).…”

“…Lyoprotectants should be mixed thoroughly with leached mince to protect proteins against denaturation (Matsuda 1971). A plate temperature of 55°C is recommended for developing FPP (Matsuda 1971(Matsuda , 1983Shaviklo et al 2010aShaviklo et al , 2012. It is possible to store FPP for a long time if it is vacuum packed or inert gas packaging is used and the products are kept at temperatures below 15°C, but the functionality loss rapidly at 30°C (Matsuda 1979;1983).…”

“…Microorganisms also cannot grow under a w 0.6 (Fontana 1998). Density of FPPs also depends on particle size, ingredients and drying temperature Shaviklo et al 2012).…”

Injection of fish protein solutions of fresh saithe (Pollachius virens) fillets studied by low field Nuclear Magnetic Resonance and physicochemical measurements

“…These can increase water and fat binding properties of the products and improve texture and stability. The functionality and sensory attributes of the proteins is however dependent on their type, origin and handling (Cunningham et al 1988;Kristinsson and Rasco 2000;Shaviklo et al 2011;Hefnawy and Ramadan 2011). Soy proteins have been used in the food industry to improve water-and fat-binding in frozen products (Cunningham et al 1988).…”