In order to isolate and clarify the antioxygenic substances from the browning reaction products, the antioxidant activity of various amino acids and their browning reaction products were measured when they were reacted with xylose. Among nonpolar amino acids Met and Trp appeared to have stronger antioxidant effect than others. Most of polar and basic amino acids, however, did not have antioxidant activity. Ser and Cys showed a rather slight prooxidant effect. The browning reaction products of Trp and His had a higher level of antioxidant activity than that they were reacted as free amino acids. But the browning product of Met did not show the antioxidant activity. When all amino acids were divided on their polar characteristics, the higher optical density of the browning reaction products showed, the stronger antioxidant activity revealed.

A study on the rapid fermentation of fish sauce has been carried out for effective utilization of sardine. The frozen sardine was thawed at room temperature, chopped, homogenized with equal amount of water and then hydrolyzed by addition of commercial proteolytic enzymes such as bromelain, papaya protease, ficin and a enzyme mixture under different conditions of hydrolysis. The effect of wheat gluten for masking fishy odor and color development during thermal treatment were also tested. The reaction mixture was heated for 30 minutes at for enzyme inactivation, pasteurization and color development and then centrifuged for 20 minutes at 4,000 rpm. Finally, table salt and benzoic acid were added for bacteriostatic effect. The results were summarized as follows ; 1. The hydrolyzing temperature, time, pH and the concentration of enzymes based on the weight of whole sardine for optimal hydrolysis were as follows: autolysis, , 4 hours, pH 8.0: with bromelain, , 4 hours, pH 6.6 :with ficin, , 4 hours, pH 6.8: with papaya protease, , 4 hours, pH 6.6: with enzyme mixture, , 4 hours, pH 6.9, respectively. But pH control was not much beneficial in increasing yield. 2. The hydrolytic reaction of chopped sardine with proteolytic enzymes could be interpreted as a first order reaction that devided into 2 periods with different reaction rate constsnts. values of the first period prior to 4 hours were 1.23 to 1.31, and those of post 4 hours were 1.25 to 1.55. The corresponding activation energies were and , respectively. 3. The reasonable amount of vital wheat gluten for addition was of chopped sardine. 4. The dark brown color was mainly developed during the thermal treatment for 30 minutes at and not changed during storage.

Very little information is available in the literature on storage of fish sauce. Therefore, microbiological and chemical chracteristics during storage and quality of fish sauce were investigated and discussed to present data about the optimum storage condition. The chopped sardine meat was mixed with equal amount of water and (w/w) of vital wheat gluten and then hydrolyzed by addition of commercial proteolytic enzymes such as bromelain, papaya protease, ficin and a enzyme mixture (Pacific Chem. Co.) for 4 hours at . The reaction mixture was heated for 30 min at for enzyme inactivation, pasteurization and color development and then centrifuged for 20 min at 4,000 rpm. Table salt and benzoic acid were added for bacteriostatic effect and stored for 80 days at and . The results were summarized as follows: 1. The amount of amino-nitrogen and pH of fish sauce were almost unchanged during storage. 2. Mininum concentration of salt for bacteriostatic activity was (w/w) regardless of addition of benzoic acid. 3. the yields of amino-nitrogen were for the hydrolysate prepared without enzyme, for that with bromelain, with ficin, with papaya pretense, and with enzyme mixture, respectively. 4. The contents of amino-nitrogen were on the dry basis for the product prepared by autolysis, for that prepared with bromelain, with ficin, with papaya protease and with the enzyme mixture, respectively. 5. The contents of crude protein were on the dry basis for the product prepared by autolysis and 55 to for prepared with commercial enzymes. 6. The hydrolysate prepared with the enzyme mixture revealed a little stronger meaty taste than any other products. 7. The level of crude protein in residues was still high ( on the dry basis) and might be originated from the added vital wheat gluten.

In succession to the previous paper, the present study was directed to investigate the effect of keeping freshness of conger eel (Astroconger myriaster) and yellowtail (Seriola quinqueradiata) by partial freezing, and the changes in the physical properties of fish meat paste product prepared with the muscle of conger eel during storage were also examined. The results obtained are summarized as follows: The period of keeping freshness (days in which k value reaches ) of conger eel and yellowtail by partial freezing was 10 days and 6 days, respectively. VBN content in the conger eel muscle showed 39.5 mg/100g by icing for 15 days, and did not show a great change by partial freezing and freezing, while that of yellowtail muscle reached at 32 mg/100g by icing, 20 mg/100g by partial freezing and 18 mg/100g by freezing for 15 days. The lipids extracted from the muscles of both fishes by icing were remarkably oxidized than those by partial freezing. The myofibrillar protein in the conger eel muscle during storage for 9 days decreased by icing, partial freezing and freezing, respectively, and that of yellowtail muscle did by icing, partial freezing and freezing, respectively. On the other hand, the alkali-soluble protein in both fishes increased with storage time. Gel strength of fish meat paste product prepared with the muscle of conger eel decreased to by icing, by partial freezing and by freezing for 10 days compared to control, and the expressible water increased 1.6 times, 1.2 times and 1.1 times by icing, partial freezing and freezing, respectively, as much as that of control product.

Nondialyzable melanoidins prepared from a glucose-glycine system were investigated as to their decolorization and degradation products on of one treatment. Melanoidins were decolorized to degree of after ozonolysis at for 10 min and 90 min, respectively, and the mean molecular weight of melanoidins decreased from 7,000 to 3,000 after ozonolysis for 40 min. IR measurement showed that the absorption at disappeared and that at newly appeared on ozonolysis, and the absorption at disappeared on acid hydrolysis after ozonolysis. Furthermore, the major degradation products in the ether-soluble fractions obtained from ozone-treated melanoidins were identified as butanedioic acid, glycolic acid, 2-hydroxybutanoic acid and so on. In the aqueous fraction, one or the major products was glycine, which was produced to the level of on ozonolysis which increased to per melanoidin on acid hydrolysis after ozonolysis. From these findings and the IR results, it is postulated that glycine was considerably incorporated into melanoidin molecules as the amide form.

Equimolar aqueous solutions of D-glucose and glycine were heated at at pH 6.7. The headspace volatiles and the ether extracts from the reaction mixture were analyzed by gas chromatography and gas chromatography-mass spectrometry using a fused silica capillary column. The major components formed were identified as diacetyl, three furfurals, two pyrroles, one furanone, two pyranones and two amides. In order to elucidate the formation mechanisms of the amides formed front amino-carbonyl reaction, two model systems were adopted. N-butylacetamide were formed as major components from diacetyl-butylamine ana glyoxal-butylamine systems, respectively. The results obtained suggest that such as 3-deoxy-D-erythro-2,3-hexodiulose and diacetyl generated in the amino-carbonyl reaction react with amino compounds, amides then being formed by cleavage of the C-C bond in the .

As one of trials to process instant sardine foods which can be preserved at room temperature, three kinds of products were prepared as seasoned-dried product (control, C), liquid smoked seasoned-dried product(S) and antioxidant treated seasoned-dried product(E), and their processing conditions and quality stability during storage were examined. Raw sardines were dressed, steamed and then filleted. The sardine fillets were seasoned with the mixed seasoning solution containing of sorbitol, of sugar, of table salt, of monosodium glutamate, of garlic powder and of water at for 15 hours, and dipped for 45 seconds in Smoke-EZ solution. After liquid smoking, the seasoned and liquid smoked sardine fillets were dried at for 4 hours, vacuum packed in laminated plastic film bag(polyester/casted polypropylene= ), and finally pasteurized in water at for 30 minutes. The results obtained from chemical and microbial experiments during storage are as follows : the moisture contents, water activity and pH of the products showed little change, and VBN of them slightly increased during storage. The TBA value and POV of the products (E, S) were lower than those of control product(C) considerably. In color values, L value (linghtness) decreased while a and b value (red and yellow) revealed a tendency to increase during storage. The fatty acid composition of the products were similar to those of raw sardine, the predominant fatty acids were 16:0, 20:5, 18:1 and 22:6. The products (E, S) have a good preservative effect on highly unsturated fatty acids during storage. Viable cell counts of those products were negative and histamine contents were less than 2.0 mg/100 g. Among the texture profiles, hardness, elasticity and cohesiveness of the products slightly decreased during storage. Judging from the sensory evaluations, liquid smoked seasoned-dried product(S) was the most desirable, and the products could be preserved in good condition for 40 days at .

The muscles of wild and cultured eel, Anguilla japonica, were analyzed for the protein composition and amino acid profile. The differences of the subunit distribution for the sarcoplasmic and myofibrillar proteins were discussed with sodium dodecylsulfate(SDS) polyacryamide gel electrophoresis. The muscle protein in wild eel was composed of of sarcoplasmic, of myofibrillar, of residual intracellular and of stroma fraction. That in cultured eel was composed of , respectively, The sarcoplasmic and myofibrillar proteins were composed of 16 and 14 subunits in wild eel, and 22 and 15 subunts in cured eel. The sarcoplasmic protein between wild and cultured muscles showed a similar trend in the subunits, except a few subunits such as 36,500, 46,000, 58,500, 75,000, 170,000 and 235,000 daltons in cultured eel. Only the existence of 45,000 dalton subunit was the difference between wild and cultured eel in myofibrillar protein. The distribution patterns of total amino acid in muscles of wild and cultured eel were found to be very similar trend, although glycine content in wild eel was slightly higher than that in cultured one.

Concentration of dissolved in the water of Okjeong lake have been determined by microbiological assay methods on the 20th of August, 1983. Also the relations between the and other physical, chemical and biological environmental factors were investigated. was assayed with Euglena gracilis Z strain. The results obtained in this investigation were as follows : 1. Generally, the values of COD and were higher than values reported in 1981. 2. The concentration of nutrient salts in the lake water was found to be at a higher level: above the general criterion in a eutrophic lake viz., phosphorous 0.175-0.225 mg/l. 3. Chlorophyll a contents in this lake were , 4. The concentration of in the water fairly high: 1.25-6.0 ng. It is apparent that concentrations of the as well as nutrient salts were high in the water of Okjeong lake. It was found that Okjeong lake was in eutrophic.

There were three important species among the marine organisms which were cultured in the inter tidal zone in the old days, and an ark-shell was one of them. Exaiming old books and reports concerning fishery were made in order to reveal the history and industrial trend of ark-shell culture. Ark-shell was called by the different names in the old days "Komak" and "Sohap". The name of Komak was originated in the southern coast area in the 1,700s, and from the begining of 18 century Komak was used only. Ark-shell was produced in all southern and western coast areas, where a little of fresh water flows into the calm inner sea and the intertidal zone is well developed. It was well known that ark-shells shell as well as its flesh took the effect of a medicine. Its culturing method in Korea seems to be derived from China in the beginning of 19 century, it was cultured first at the southern area of Chollanam-do. It was considered as the side business, but after Korean war it is produced on the basis of cooperative work, now its production is quite increased (more than ) due to the goverments development policy.

The activity of the liver cells of greenling, Agrammus agrammus were histologically investigated under photo-and electron microscopy, and studied by comparing seasonal changes of hepatosomatic index (HSI). The materials were monthly collected at the costal area of Tongbaeksom, Pusan, Korea, from September 1983 to August 1984. The annual variations of HSI of male were not distinct, but those of HSI in female began to increase in autumn, and reached the maximum in winter when the ovary was getting mature. During the period of yolk accumulation in the oocytes, the female liver and its hepatic cells were seen to large and nuclei and nucleoli were hypertrophic also. At this time the amounts of glycogen and lipid in the cells gradually decreased, while basophilic substance (RNA) increased. And well-developed granular endoplasmic reticula binding ribosomes were supposed to play the leading role in protein synthesis and deposition for vitellogenin in the cystoplasm. Just prior to spawning, glycogen and lipid droplets were decreased, but basophilic substances(RNA) were found in a high concentration especially at the peripheral region of the liver cells of females. In the liver cells of males, were hardly altered by gonadal maturation, basophilic substances gradually increased, glycogen particles and lipid droplets were still observed in large quantities. After spawning, basophilic subtances decreased in the liver cells of female and male.