魚肉ソーセージの軟化現象について-I

Abstract

Recently, fish sausage has risen to be one of the important marine products in our country. This article is manufactured essentially from the meat of fish such as black marlin or from the mixture of this and yellowfin tuna. In addition to the fish meat, small amount of potato starch and the fat of porks are added as sub-materials. After being minced the fish meat is ground into a paste along with these sub-materials and various spices. The meat paste, after being colored with a synthetic red pigment, is packed into a casing of chlorinated rubber or vinyliden chloride by an air stuffer and then sealed up with cotton or hemp thread. Finally it is cooked in a hot water bath at 80-90°C. for about 50 minutes. Fish sausage manufactured in such a way belongs to the articles referred to as semipreservative food. Although the product is generally expected of its preservability covering a month or so, sometimes are found degraded articles showing various types of spoilage among the commercial fish sausages especially in a summer season (see Table 1). The softening is a peculiar type of spoilage of fish sausage and given rise to sporadically in the inside of the product as seen in Fig. 1. This spoilage is different in some respects from the common spoilage familiar among fish meat or other fish jelly products. The results of experiment will be summarized as follows; 1) The softening spoilage is not observed in freshly prepared fish sausage. Presumably, the spoilage has no relation to the deteriorated meat like the jelly meat and the honey comb which are occasionally met with in canned products. 2) The quantity of ether soluble fatty acid, as shown in Table 2, increases in the softened portion more markedly than in the non-softened portion; and the pH value seems to affect the quantity of such fatty acid. But no difference in volatile basic nitrogen is found between the softened portion and the non-softened. 3) When Cl. sporogenes or Cl. welchii is allowed to act on the sterilized fish sausage meat paste, the softening is also produced always in accordance with gas formation, sometimes being attended by a vile smelling. The softening deterioration mentioned above, however, never produces either gas or vile smelling at all. Furthermore, no relation is found to hold between the softening deterioration and the presence of spore-forming anaerobes as seen in Table 1. 4) From the results of microscopic observation on the softened portion, it may be pointed out that starch granules in the softened portion has been substantially disintegrated as seen in Figs. 4 and 5, while those in the un-softened portions are not so (Figs. 2 and 3). From these facts, the softening of the sausage seems to be effected through the disintegration of the starch granules. 5) There are considerable resenblances between the softening deterioration of fish sausage and the flat sour spoilage of canned foods in some points of view.