Orange Oil as a Preservative for Fish Sausage

Fish sausage is ground fish meat, or a mixture primarily of ground fish with ground pork, together with vegetable oil, permissible preservatives, seasoning and starch. It is packed in a casing and processed. It is a semi-processed food, the time and temperature of processing of the product being not sufficient o kill all micro organisms. Thermotolerant and spore-forming bacteria survive the processing and bring about spoilage. Consequently, chemical preservatives are used to prevent the growth of these. Preservatives such as nitrofurazone, sorbic acid and tylosin1,2) used in other countries for preservation of fish sausage, are not permitted in our country. The use of an easily available, natural preservative, with effectives preservation action, will therefore, help in the development of fish sausage industry in the country. The germicidal activities of several essential oils possessing remarkable lethal action against a series of pathogenic and nonpathogenic bacteria and fungi have been reported 3,4). The disinfectant power of lemon and orange essences in aqueous solu tion against spore-bearing organisms was found to be greater than that of phenol5). Cold-pressed (undistilled) orange oil (0.1%) exerted a toxic effect upon Streptococcus faecalis6). Orange oil and d-imonene exhibited lethal properties against Zygosac charomyces major at 0.02% concentration in aqueous solution and at 0.1% in orange juice, respectively7). d-Limonene was more effective than orange oil in both water and orange juice. The study further indicated that orange oil and d-limonene in con centration as low as 0.02% increased the preservative effect of sodim benzoate. Brown mustard powder or volatile oil of mustard and orange oil were inhibitory to yeast8). Oxidized d-limonene shifted the lag-phase in the growth of the yeast culture. A preservative emulsion for pickles from acetic acid, orange oil and powders of brown mustard and turmeric has been prepared9). This prevented the growth of micro organisms in pickles even when the concentration of salt or acid, or both was low, without significantly altering the taste and flavour of the pickles. Addition of cinna mon, clove and mustard oil improved the keeping quality of fresh water fish-fillets10). The preservative effect of orange oil or other essential oils in the case of fish sausage has not been studied. The object of the present invesigation was, therefore, to study the preservative effect of orange oil on fish sausage.