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BACKGROUND: Funazushi is a fermented sushi containing n3 polyunsaturated fatty acids. Moreover, the functionality of lactic acid fermentation foods has come to be expected. Funazushi is therefore worthy of study. Funazushi has a specific flavor which is either strongly liked or strongly disliked. We examined the components of funazushi and investigated their relation to preference.

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Funazushi (fermented Crucian Carp with rice) is a fermented fish product found only around Lake Biwa in Shiga Prefecture, Japan. It is characterized by a unique cheese-like flavor and characteristic sour taste. We analyzed the changes in the microbial community during funazushi fermentation by denaturing gradient gel electrophoresis of PCR-amplified 16S rDNA fragments (PCR-DGGE) and by plate counts. The plate counts showed that lactic acid bacteria reached 8.0 log 10 CFU/g within 7 days of fermentation initiation before decreasing slowly to 4.0 log 10 CFU/g during the remainder of 1-year study period. PCR-DGGE revealed that the dominant bacteria in the initial (days 14 and 30) and latter (days 90, 180, and 360) periods of fermentation were Lactobacillus plantarum and L. acetotolerans. This is the first identification of L. acetotolerans in funazushi as traditional cultivation techniques have not been sufficiently sensitive. This is the first report of PCR-DGGE being used to assess the microbial community in funazushi. This technique was also found to be effective in profiling microbial diversity.

Changes in ultrastructure of protein bodies in subaleurone cells of rice endosperm during germination were studied by transmission electron microscopy. Thesubaleurone cells contained two different types of protein bodies: PB-I (spherical) and PB-II (crystalline).Both types of protein bodies were deconstructed during germination. But there was a considerable difference in digestibility between PB-I and PB-II. PB-II which did not have a dense core was easily digested from the central portion when germination began. At 6 days of germination, PB-II was almost deconstructed. On the other hand, PB-I which displayed concentric rings with a dense core was digested from the outside after 3 days of germination. At 9 days of germination, many kernels of the spherical protein bodies remained. Changes in subunit composition of protein bodies during germination were investigated by SDS-polyacrylamide gel electrophoresis.Protein body fractions were isolated from germinating grains at various stages by enzymatic digestion and two-phase system, then subjected to SDSpolyacrylamide gel. As germination proceeded, 15 (bx), 20 (dx), 24 (e), 35 (fx) and 37 (f3) kdaltons subunits decreased. On the other hand, 16 (b2), 21 (d2) and 36 (f2) k daltons subunits remained at the later stage of germination. Wethink that PB-I contains b2, d2 and f2 subunits and is attacked only from the outside at middle and later stages of germination by de novo protease. Onthe contrary, PB-II contains bl5 dls e, fx and f3 subunits is utilized at an early stage of germination. PB-II may possibly contain latent protease. The breakdown process ofPB-I was by exo-type digestion, on the contrary, that of PB-II was by endo-type digestion.Reserve proteins in various seeds are localized in subcellular storage particles. A predominant protein of rice, glutelin, exists in the endosperm,1>2) while globulin is mainly loca- scribed that the dense centers of protein bodies from cooked rice were not digested by human. Recently we reported the effect of cycloheximide on protein breakdown in germinating rice seeds and showed that the glutelin breakdown was affected by the inhibitor of protein synthesis and there were two types of glutelin, an easily-digested type and a hard one.U) In this paper, we demonstrate the difference in digestibility during germination between two types of protein bodies in subaleurone