The reactions of 10 captive Steller sea lions Eumetopias jubatus, including one adult male, four adult females and five juvenile animals to underwater sounds, with and without the presence of a baited fishing net, were observed. Two narrow spectrum sounds, an 8 kHz pure tone and a 1 kHz to 4 kHz frequency sweep, three broad spectrum sounds, two mechanically generated impulse sounds, and the recorded vocalization of a killer whale were used. The reactions of Steller sea lions were divided into three categories. Category Ο: Both adult and juvenile Steller sea lions landed on a side of their pool during a one-minute period timed from the start of the sound projection. Category Δ: More than two juvenile Steller sea lions landed. Category ×: A single juvenile Steller sea lion or no animals landed.
Impulsive sounds transmitted at high source level (210 dB re 1 μPa at 1m) or pure tone sounds(165 dB source level) were found to repel adult Steller sea lions. Broad band spectrum sounds did not repel adult and juvenile Steller sea lions after successive sound projections.
The male Steller sea lion was only deterred from eating the fish entangled in the net by the high source level impulsive sound.
The acoustic characteristics required to repel Steller sea lions are thought to be narrow spectrum with-in the sensitive range of a Steller sea lion's audible frequency and above 165 dB sound pressure level. However, Steller sea lions appear to acclimatize to repeated sound projections, and a sound pressure level below 165 dB does not appear to be enough to repel Steller sea lions from a fishing net.

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Cell morphology in the paired medullary facial taste nuclei, the facial lobe (FL) of the sea catfish Plotosus lineatus was studied in Nissl and Golgi-impregnated materials. The central projections of the facial nerve rami to the FL were examined by transganglionic labeling with horseradish peroxidase (HRP).
The FL is extraordinarily developed in the sea catfish, correlating with an enormous number of taste buds on the lips, the adjacent oral mucosa, four pairs of barbels, and over the whole body surface.The FL is divided by fiber fascicles into highly distinct lobules, constituting 5 longitudinal columns through the FL. These lobules begin approximately at the level of posterior one-third of the FL and extend rostrally. Small (7-9 μm) and large-sized (15-20×12-15 μm) neurons are present in the barbel lob-ules. Small neurons form cell clusters in the lobules and large neurons are mainly present in the periph-ery of the lobule. Golgi analyses revealed that the small neurons are possessed of 50-60 μm dendritic fields around them, while the larger ones have thick dendrites of 150 μm in length.
Transganglionic tracing of the peripheral facial rami with HRP showed a distinct somatotopic projection of the rami to the FL. Four lobules (from medal to lateral) have connections with the medialmandibular, lateral mandibular, maxillary, and nasal barbels, respectively. The fifth lobule, located dorsolateral to the other lobules, receives input from the body surface. The upper lip, lower lip and an-teriorpalate behind the upper lip are represented in the lateral, medial and ventral prtions of the posterior one-third of the FL, respectively.
Tracing experiments also showed that the trigeminal fibers contained in each faial ramus project directly through the descending trigeminal tract to the limited region of the FL wherethe facial fibers in the same ramus also project. These results showed the distinct topographical organization in the FL for the trigeminal fibers in registerwith corresponding facial fibers.

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Histological observations were performed to clarify the developmental process ofthe perivisceraladipose tissue in the early life stage of the red sea bream, Pagrus major. The adipocytes were first observed in the pancreas of 37-day-old juveniles. Development of the adipose tissue progressed in the pan-creas covering the intestine. Tissue volume (Day 37 to 56) increased acutely with growth of the fish. On the other hand, no significant change was recognized in the average size of adipocytes in this period.This result suggests that hyperplastic growth by active recruitment of precursor cells predominates the early development of the adipose tissue.

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Age and growth of the largemouth bass Micropterus salmoides (Pisces: Centrarchidae) were estimated from otoliths taken from samples collected in Lakes Shorenji (Mie Prefecture) and Nishinoko (Shiga Prefecture), water bodies having different physical and biological environments, from October 1991 to March 1993. The otoliths of the fish had narrow opaque and wide transparent zones, with opaque foci. Ring marks (outer margin of opaque zones) were formed on the otoliths once a year from June to August and May to July in Lake Shorenji and Lake Nishinoko specimens, respectively. The number of ring marks indicated approximately the full age of the fish because the marks formed one or two months after the spawning period. The fish from Lake Nishinoko were significantly heavier than those from Lake Shorenji for the same length. The growth curves for length were calculated to be SL_n=341(1-exp(-0.4977(n+0.0697))) (Lake Shorenji) and SL_n=362(1-exp(-0.4576(n+0.0892))) (Lake Nishinoko). Lake Nishinoko largemouth bass grew somewhat more rapidly than those in Lake Shorenji.

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The age and growth of ribbon fishes Trichiurus japonicus in Kagoshima Bay were estimated from otoliths. Bimonthly changes in the marginal growth index indicatedthat the annulus was formed once a year, between December and February. A singlemode in the frequency distribution of preanal length for each age group suggested that each of the latter comprised a single cohort, probably born in sum-mer.One-to six-year age groups were recorded for females (pre-anal length range 190-447mm) and one-to five-years for males (pre-anal length range 199-383mm). Back-calculated pre-anal lengths were fitted to von Bertalanffy's growth equation separately by sex. Females grew faster and reached a larger size than males. The possibility of compensatory growth between larger and smaller fishes after the firstyear was suggested. Growth of the Kagoshima Bay population was compared with that of the same species from other two localities in Japan.

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The visual contrast threshold of Japanese common squid was studied using contrast test boards newly equipped with on-off switches. This improved apparatus enabled us to judge exactly the jet-hit response of the squid under very low ambient lights. Background brightness was maintained at four light levels, the quantum irradiance ranging from 2.3×10^-1 μEm^-2 s^-1 (equivalent to about 4.1 lx) to undetectable levels (darkness). The apparent contrast values of the test board ranged from 33.6 to zero (0).
At the light levels of 2.3×10^-1, 1.8×10^-3, 8.0×10^-5 μEm^-2 s^-1 and at dark, the contrast threshold values of the squid were estimated to be 0.007, 0.008, 0.014, and 0.025, respectively, increasing with decreasing irradiance. At dark, the threshold was approximately four-fold that obtained previously at 1.0 lx. These experiments suggest that the background brightness by which the contrast threshold of the squid is influenced is less than 1.8×10^-3 μEm^-2 s^-1.

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Edwardsiella tarda strain ET16 isolated from the liver of diseased eel Anguilla japonica could secret a hemolysin across cell membrane rather than cell-associated hemolysins that are reported by most known E. tarda strains. Hemolysin exported to the culture medium was partially purified by the application of Sephacryl S-100 HR and DEAE-Sephacel. The molecular weight of the functional hemolysin protein was estimated to be approximately 34 kDa by the recovery of hemolytic activity in situ after SDS-PAGE. The action of the hemolysin on tilapia erythrocytes was scrutinized under SEM. E. tarda hemolysin caused holes between 0.5-2.5 μm indiameter to be formed on the membrane of the tilapia erythrocytes.

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The cryopreserved spermatozoa of seven species of puffer, Takifugu niphobles, T. pardalis, T. poecilonotus, T. porphyreus, T. radiatus, T. rubripes, and T. xanthopterus were observed with a transmission electron microscope. The spermatozoa of these species had a round-shapedhead, a midpiece which contained mitochondria, and a tail. The nucleus of the spermatozoa of the seven species are unusually elongate, and the chromatin of the nucleus is an electron dense structure. In the midpiece, 7-9 independent mitochondria encircle the flagellum of the spermatozoa. The axoneme has two lateral fins relative to which the plane of the two central singlets is slightly tilted. Internal morphology of the spermatozoa of the seven Takifugu species closely resemble one another in their head structure, midpiece structure, and axoneme structure. It is concluded that the spermatozoa of the seven species can not be readily identified from their morphology.

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The cultivar discrimination of the laver (Porphyra yezoensis and P. tenera) was examined with random amplified polymorphic DNA (RAPD) analysis using purified genomic DNA and arbitrary primers. A total of 91 primers were used for the preliminary screening of RAPD primers, 18 of which were found to generate polymorphic PCR products (RAPD markers) among six cultivars. Eight of the 18 produced RAPD markers which were found in specific single cultivar and the other ten primers produced RAPD markers which were shared by more than two cultivars. Six cultivars could be distinguished by the combination of these RAPD markers. RAPD banding patterns were similar among independent lots of DNA extraction and among three thallus samples which were identical in cultivar but cultured and harvested in different years. These results suggested that RAPD markers were reproducible and stable during the culture of thalli and long-term propagation of concho elis, and therefore were genetically significant. RAPD analysis thus appears to be helpful in the discrimination of laver cultivars.

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Dinucleotide repeat polymorphisms are widely used as markers for genetic analysis in mammalian genomes because of their abundance and high variability among individuals. We have previously isolated informative markers for genetic studies of rainbow trout. In fisheries science, many species need to be analyzed. Therefore, heterologous applications of DNA markers designed in one species can be useful. The sequences flanking a dinucleotide repeat are often conserved among closely related species. We thus wanted to determine whether DNA markers isolated from the rainbow trout genome could be used to detect dinucleotide repeat polymorphisms in five other species of salmonid. Five sets of primer pairs that flank rainbow trout microsatellites and that produced polymorphic PCR products, were tested with template DNA from five species. Specific PCR products were obtained in all cases. Four out of five DNA markers could detect polymorphism in all speciesand all five DNA markers could detect polymorphism in at least one species. In many cases, these markers showed large numbers of alleles and high heterozygosity values in other salmonids such as rainbow trout. Our results show that DNA markers isolated from rainbow trout are also useful in other salmonids for fisheries sciences such as population studies and genetic linkage analysis.

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A monoclonal antibody was prepared against specific strains of the fungal parasite, Pythium sp., the causative organism of red rot disease of Porphyra, and its effectiveness in the early detection of the fungal pathogen was assessed. The antibody recognized germ-tubes of zoospores from Aichi, Saga and Miyagi Prefecturesbut failed to identify non-germinating zoospores. The isotype of the antibody was IgG₁. Based on chemical and enzymatic treatments, the antigenic determinant was thought to involve glycoproteins of the germ-tube cell wall. For the enumeration of zoospores in seawater from Porphyra cultivation farms, seawater was pre-filtrated by 40 μm nylon mesh and zoospores were concentrated on 3 μm membrane filters and incubated in glucose-glutamate medium for 8h at 20°C. Germinating zoo-spores were detected by epifluorescence microscopy using the indirect fluorescent antibody technique. During the Porphyra cultivation season in Tsu, Mie Prefecture, germinating zoospores were detected from a farm employing a pole cultivation system. Between January 7 and February 13, 1995, numbers ranged from 11 germinating zoospores/l (the detection limit) to 4695 zoospores/l on January 25. No germinating zoospores were detected in seawater from a cultivation farm using a floating-net system despite the fact that diseased Porphyra thalli were observed in this farm.

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To estimate the scale effect on the modeling of fishing nets, six prototypes andtwo models of plane nets were prepared in experiments. The ratio of the twine diameter between the model and the prototype satisfied Tauti's law of similarity. Drags of each net, which were mounted on a streamline frame, were measured in a flume tank. The measured drags of the prototype nets were compared with the drags converted from the measured drags of the model nets according to Tauti's law.
The results showed that the converted drags of the prototype nets were higher than the measured drags. These differences caused by the change of the drag coefficient can be expressed as a function of Reynolds number in Tauti's law. To correct the scale effect on the converted drag, the curve relating the drag coefficient, C_d, within the wide range of Reynolds number, R_e, C_d-R_e curves, should be confirmed by experiments for many kinds of net.

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A stochastic model on the hooking mechanism representing the capture probability of fish which bit on a hook was made. It was assumed that a fish could not remove a hook once a hook had stuck. Notice was taken of hook movement in the mouth cavity of a fish, so that the difficulty in a hook entering the mouth cavity wasshown by the hard entering coefficient, which indicated the possibility of stop of the inward movement of the hook, and the ease of hooking was shown by the hooking coefficient, which indicated the possibility of hooking for the outward movement of the hook. The stop probability of the inward movement of the hook and the hooking probability were expressed by using these coefficients. The capture probability was derived from these probabilities. The model fitted well with observations from experimental pole-and-line fishing. Consequently, the hard entering coefficient and the hooking coefficient could be represented by functions which consist of two variables, hook width and total length of fish.

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The structure of elastic appearance of kamaboko was discussed by the thermodynamic theory of elastic deformation. The thermistor was inserted into kamaboko sample gels, and the temperature was measured as the gels were stretched at the rateof 20cm/min. As a result, the temperature of the sample gels decreased right after the temperature increased. However, it is unlikely that a rapid variation oftemperature of kamaboko occures in the atmosphere, because kamaboko will have almostthe same magnitude of specific heat with that of water, and the cause for the temperature increase and decrease were examined. The increase in temperature when thesample gels were stretched was explained by the temperature distribution within the gels being low and high temperatures at the middle part and surface of the gels, respectively. On the other hand, the temperature decrease right after the emperature rise was likely caused by the heat of moisture vaporization when the surface area of the samples were expanded accompanied by stretching. The factors fortemperature changes in kamaboko when it is stretchedcan be explained by factors other than the Gough-Joule effect. Therefore, it is not enough to conclude that kamaboko has an entropy elastic body only by the results from the apparent temperature increase.

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Thermal stability of the pepsin-solubilized Type AR-I collagen was estimated by monitoring the protease-induced degradation of helical domains by SDS-PAGE. The pepsin-solubilized Type AR-Ia collagen, designated as [α1(AR-I)]₃, denatured at 34.7°C. On the other hand, the α1(AR-I) and α2(AR-I) components in the mixture of the pepsin-solubilized Type AR-Ib and AR-Ic collagens, [α1(AR-I)]₂ α2(AR-I) and α1(AR-I)[α2(AR-I)]₂, respectively, showed transition midpoints of 33.5 and 33.8°C, respectively. From these results, the pepsin-solubilized Type AR-Ib and AR-Ic collagens were less stable to heat than the pepsin-solubilized Type AR-Ia collagen. In addition, the α2(AR-I) component in the intact Type AR-Ib and AR-Ic collagens in the residual fraction after alkali (0.1 N NaOH) extraction from muscular tissue showed an approximate transition midpoint of 37.9°C. These combined resultssuggest that the thermal stability of intact Type AR-Ib and AR-Ic collagens are considerably reduced by pepsin digestion which causes the removal of their telopeptides and change of their molecular properties such as molecular arrangement or solubility.

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The effects of seaweed diets on the lipid and fatty acid (FA) composition of juvenile abalone Haliotis discus hannai were investigated by feeding seaweeds with different FA profiles: green (Ulva pertusa, rich in 16:4n-3, 18:3n-3, and 18:4n-3 polyunsaturated fatty acids or PUFAs), red (Grateloupia sparsa, high in 20:4n-6 and 20:5n-3 PUFAs), and brown (Undaria pinnatifida, rich in 18:3n-3, 18:4n-3, 20:4n-6, and 20:5n-3 PUFAs), in a 66-day feeding trial. The best growth was observed in juveniles fed U. pinnatifida. None of the seaweed diets affected the major lipid classes of abalone tissues. The PUFAs, 16:4n-3, 20:5n-3, and 22:5n-3 were major FAs of abalone tissues even if these were undetected or found only in very small amounts in the seaweed diet, suggesting their synthesis from dietary n-3 series of lower fatty acids. The poor growth rates were associated with seaweed diets deficient in 18:2n-6, 18:3n-3, 18:4n-3, or 20:4n-6.

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The effects of seaweed diets on the growth and biochemical composition of the white sea urchin Tripneustes gratilla were studied using three seaweeds with different fatty acid (FA) profiles: Ulva pertusa (green alga, high in 16:4n-3, 18:3n-3, and 18:4n-3 polyunsaturated fatty acids or PUFAs), Gloiopeltis furcata (red alga, rich in 20:4n-6 and 20:5n-3 PUFAs) and Undaria pinnatifida (brown alga, abundant in 18:3n-3, 18:4n-3, 20:4n-6, and 20:5n-3 PUFAs). Specific growth rates (dry weight basis) were the highest in the animals fed Undaria (including the mixed algal diet), followed by Ulva and Gloiopeltis. The highest feed conversion efficiencies (on a dry weight basis) were with Undaria (80.0%) and Ulva (76.6%) while the lowest was with Gloiopeltis (51.5%). All algal diets did not affect the major lipidclasses of the sea urchin tissues. The poor growth rates associated with a seaweeddiet deficient in 18:3n-3, 18:4n-3, or 20:4n-6 (such as Gloiopeltis and Ulva) suggest that these FAs may be essential for juveniles of the white sea urchin.

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Aspergillus repens, a popular saprophyte in “katsuobushi” molding, induced the lipase and phospholipase production in the semi-defined liquid media containing 1% casamino acid and 20% glycine with the addition of olive oil or phosphatidylcholine, respectively. The mold consumed the free fatty acids, liberated from lipids contained in medium. These enzymes were detected inthe sliced product medium of broil-dried skipjack meat during the molding process, and the growth of A. repens caused the decrease of lipid content.
The distribution of glucosamine, indicator of mycelium growth, in commercial “katsuobushi” revealed that A. repens grew only on the surface. The results indicate that the molding process contributed to the hydrolysis of lipids by the enzymes andthe subsequent decrease of lipid concentration by the consumption of liberated free fatty acid on the surface of “katsuobushi”.

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Post-mortem changes of α-connectin in muscle of six fishes were not linked with the softening of raw fish muscle during one day-chilled storage. Muscle firmness was evaluated as breaking strength. Alpha and β-connectins were resolved by electrophoresis and the relative density of α-connectin band to total connectin bands was determined by the integration of the peak areas in densitograms with gaussian algorithm. Relative density of α-connectin band decreased extensively in non-softened muscles during one day-chilled storage. On the other hand, a decrease of α-connectin were relatively small after a storage even in the softened musclesuch as rainbow trout and sardine.

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The dielectric properties of carp myofibrils in the presence and absence of electrolytes under frozen conditions were measured. Unfrozen water was characterized by the apparent dielectric relaxation time (τ) and apparent activation energy calculated. The unfrozen water was divided into three groups that had different relaxation mechanisms by a Cole-Cole plot. The temperature-dependence (reciprocal of absolute temperature) of τ (Arrhenius plot) presented a biphasic pattern with a breaking point at -15.3 and -23.2°C in the absence and presence of electrolytes, respectively. In the temperature range from the breaking point to the lowest temperature examined, it seems that the unfrozen water is “unfreezable water” andcorresponds to monolayer water. At the same time, it is considered that unfrozenwater in the temperature range from the breaking point to the highest temperature examined corresponds to the bound water of multilayer water. The mobility of unfrozen and unfreezable waters increased in the presence of electrolytes under the temperatures examined.

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Bile salts in twenty six species of fish were examined to investigate the bile salt composition and the distribution of D-cysteinolic acid conjugated bile saltsby high-performance liquid chromatography and/or thin-layer chromatography densitometry. Their major bile salts were cholyltaurine and/or chenodeoxycholyltaurineexcept for the bile salt in Japanese dace which exclusively consists of cyprinolsulfate. A considerable amount of unconjugated cholate was also found in ayu fish. D-Cysteinolic acid conjugates were detected in the bile of wild and aquacultured guelly jack, brackish goby and marbled rockfish as well as red seabream. No D-cysteinolic acid conjugates was found in biles of Japanese sardine and mackerein spite of existences of D-cysteinolic acid in their muscle and liver.

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The effect of broodstock diets on the chemical components of eggs produced by yellowtail was investigated to collect some basic data necessary for the development of a quality dry pellet for this species. The assessment was done by feedingyellowtail broodstock with either frozenraw fish (RF), moistn pellet (MP) or soft-dry pellet (SDP) for about 2 ¹/₂ months prior to spawning. Themilt, buoyant eggs and larvae obtained from yellowtail broodstock of each testdiet group were analyzed for lipid classes, fatty acids, carotenoids, and vitamins A and E.
Eggs and milt obtained from yellowtail broodstock fed the various types of dietsshowed the typical pattern of fatty acids found in marine pelagic eggs and milt. Those derived from broodstock fed SDP contained the highest level of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). It was noted here again that the fatty acid profile and vitamin E content in eggs and milt were related to their availability in the broodstock diets. The carotenoid composition of the eggs was also greatly affected by the conversion or deposition of carotenoid from broodstock diets. In this study, egg quality was found to be high in brood fish which had been fed SDP containing 10% krill meal. They possessed a strong yellowish color with a high content of zeaxanthin and lutein. The eggs from the MP group werecomparatively lighter in color and those from the RF were still paler. Consequently, the quality of the yellowtail eggs seemed to be related to the carotenoid contained in them.

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The effects of varying dietary protein level on several nutritional parameters of Sparus aurata fry were studied. Seven approximately isoenergetic diets were formulated with protein levels ranging from 35% to 65%, in increments of 5%.
Highest specific growth rates were obtained in fish fed 55% protein at a fixed dietary feeding rate of 6% body weight per day, being significantly different from the other fish groups. Feed efficiency was significantly higher with diets containing the highest protein levels, when compared with dietary levels below 45%. Protein efficiency ratio values showed a trend towards an increase up to a maximum with 55% dietary protein, whereas carcass composition was only slightly affected. The minimum dietary protein level producing maximum growth of S. aurata fry was found to be 55%.

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A feeding trial was conducted to determine the sparing effect of lipids on dietary protein in giltheadsea bream Sparus aurata fingerlings, by combining different levels of protein (42-58%) at two lipid levels (9, 15%) in the diets. Sardinemeal and sardine oil were employed as the main source of dietary protein and lipid, respectively. Weight gain and specific growth rate of fish improved for each dietary protein level when lipids were increased in diets from 9% to 15%, up to 52% dietary protein. There was evidence of a protein sparing effect of dietary lipid, as evident by a reduction of dietary protein from 52 to 46%, and an increase of dietary lipid from 9 to 15% in diets resulting in slightly better fish growth. There were no significant effects on the protein efficiency ratio. The increase of dietary lipid producedan increase in body lipid deposition, both in visceral and non-visceral tissues.

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The aqueous extract of the sea anemone Radianthus crispus was potently lethal tocrabs but had no toxicity in mice. A polypeptide toxin (named Re I) was easily isolated by gel filtration on Sephadex G-50 and reverse-phase HPLC on TSKgel ODS-80Ts. Its minimum lethal dose against crabs was estimated to be 7.3 μg/kg. The complete amino acid sequence of Rc I was determined by sequence analyses of S-carboxamidomethylated toxin and its enzymatic fragments. Rc I comprises 47 amino acid residues and is characterized by the abundance of Asx, Gly, and half-Cys, the absence of Ala, Met, and Tyr, and the presence of an unusual amino acid, hydroxyproline. As compared with the sequences of the known sea anemone toxins, Rc I is ananalogue of type 1 toxins, showing an especially high homology with Cp I (89%) and Cp II (81%) from the Caribbean sea anemone Condylactis passiflora.

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The present paper describes the fatty acid composition of the lipids of albacore Thunnus alalunga caught in two separate localities in the temperate zone of the northern Pacific Ocean. The total lipids of various organs (dorsal ordinary muscle, ventral ordinary muscle, dark muscle, liver, heart, pyloric cecum, and orbital region around the eye) and stomach contents were extracted, and the fatty acid composition was analyzed by gas-liquid chromatography.
Docosahexaenoic acid (DHA; 22:6n-3) was the major unsaturated fatty acid in the lipid of all specimens examined. The mean DHA content accounted for more than 25% (mean±s. d.: 26.5±5.8%) of the total fatty acids in the lipids of all organs. This was different from the lipid profile of other fish species, of which the fatty acid composition generally is more variable. The DHA contents of lipids of albacore were higher than those of other fish species, but similar to those of other tuna species (genera Thunnus and Euthynnus).

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Seasonal variations in contents of glycogen and its metabolites in scallop adductor muscle and their influences on browning during cooking were studied.
Glycogen content was lowest in January (0.49%) and highest in June (6.60%). The content of glucose ranged between 0.1 and 0.9 μmol/g in winter and spring, and exceeded 1 μmol/g in summer whenglycogen was abundant, and it retained the level throughautumn. The content of glucose-6-phosphate (G6P), which amounted to about 80% of total amounts of sugar phosphates, varied from 0.3 to 3.5 μmol/g, and tended to be abundant in summer.
During storage of unfrozen scallop adductor muscle, glycogen was converted to G6P. The higherthe content of glycogen, the larger the increase in G6P content, which led to a strong browning ofcooked muscle. Accumulated G6P during thawing was not affected by glycogen content, though a stronger browning during cooking was observed in the muscle containing larger amounts of glycogen. Whenfrozen and thawed muscle was stored at 5°C after thawing, muscles containing larger amounts of glycogen showed a further increase in G6P, which resulted in an increase in the degree of browning, but muscles containing smaller amounts of glycogen showed decrease in G6P, which resulted in decrease inbrowning. The glycolysis which progresses during storage and cooking seems to influence the browningof cooked scallop adductor muscle.

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Abalone meat was cooked for 0, 15, 30, 60, 180, and 360min, and changes in the taste and texture during cooking were studied. During cooking, the weight of meat decreased, and it was 65% of the original weight after cooking for 360min. Collagen content in the meat decreased with a concomitant decrease in the hardness of meat (r=0.82). The amount of adenosine 5'-monophosphate increased after cooking for 15min and leveled off. The total amount of free amino acids increased after15-30min, then decreased. On the contrary, the amount of oligopeptide-bound amino acids kept increasing until 360min, both in the cooked meat and the drip. In the dominant amino acids of the oligopeptides, collagen constituents amino acids such as glycine, hydroxyproline, and proline were included. By the sensory test, the characteristic abalone taste and odor became stronger as the cooking time increased. This might be the reason why Japanese cookbooks recommend cooking for an extended period such as 15 or 180min.

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