The Effect of Alkali Pretreatment on the Physicochemical and Rheological Properties of Iranian Beluga Fish Gelation
Subject Areas : Microbiologyسمیرا Sabagh Pour 1 , علی Motamed Zadegan 2 , میلاد Hadidi 3
1 - کارشناس ارشد گروه علوم و صنایع غذایی، واحد علوم و تحقیقات آیت الله آملی، دانشگاه آزاد اسلامی، آمل، ایران
2 - استادیار گروه علوم و صنایع غذایی، دانشگاه علوم کشاورزی و منابع طبیعی ساری، ساری، ایران
3 - کارشناس ارشد گروه علوم و صنایع غذایی، واحد علوم و تحقیقات آیت الله آملی، دانشگاه آزاد اسلامی، آمل، ایران
Keywords: Extraction Pretreatment, Gelatin, Iranian Beluga Fish, Rheology,
Abstract :
Introduction: Gelatin is a natural biopolymer that is most widely used in food industry. Commercial gelatin due to its social, cultural and religious reasons are not acceptable by some therefore, gelatin extracted from fish processing waste might be employed as an alternative source for commercial gelatin. Materials and Methods: In order to optimize the extraction of gelatin from the skin of Iranian beluga fish ( Huso huso), the effect of different concentrations of NaOH (0.01, 0.05 and 0.075 N) and Ca(OH) 2 (0.01, 0.05 and 0.075N) on the extraction yield, melting point, viscosity, gel strength, colour and the molecular weight of extracted gelatin were investigated. Results: The results indicated that the highest extraction yield was obtained when 0.05 N Ca (OH) 2 was employed. The highest and lowest melting points (30.98 and 28.0°C) were related to the treatments concerned with 0.01N NaOH and 0.05 N Ca (OH)2 respectively (p< 0.05). The viscosities were increased as the alkali concentrations were reduced, however sodium hydroxide concentration affected the viscosity more than calcium hydroxide (p<0.05). Gel strength was affected more by 0.01N sodium hydroxide. There were not significant differences between the treatments concerning colour changes. Conclusion: The results indicated that 0.01 N NaOH treatment produced gelatin with improved functionality and characteristics.
