• Korean journal of food and cookery science
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• v.5 no.1
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• pp.69-74
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• 1989

Trans fatty acids are formed during refining process of vegetable oils (deodorization), hydrogenation, the high temperature treatment of oils and rancidity. Trans fatty acids contents were measured in vegetable oils added to tuna, oyster and mussel Can by Glass Capillary Gas Chromatography. Also Acid Values, Peroxide Values, iodine Values and Saponification Values of vegetable oils added to Can were determined. The results were as follows; 1. Among vegetable oils added to Can, trans fatty acids isomer of cotton seed oil were mostly t,c-18:2 and t,c,c-18:3. 2. Total average contents of trans fatty acids of soybean oil added to tuna Can (Ab) were shown the highest values among tuna (Aa, Ab), oyster, mussel (Cb) Cans. 3. All of oils added to Can had been keeping safe quality during 1 year or more with low Acid and Peroxide Values.

• Applied Biological Chemistry
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• v.47 no.3
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• pp.307-314
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• 2004

Specification and heavy metal contents of canned seafoods packed in oil were investigated. 30 species of canned tuna were classified by 4 groups as follow; group (sample codes, 1-10) composed of tuna and oil only, group (11-18) composed of tuna, vegetable and oil, group (19-27) composed of tuna, sauce and oil, and group (28-30) composed of tuna, vegetable, sauce and oil. Commercial canned shellfish packed in oil were mainly produced from sea mussel (sample codes, 31 and 32) and oyster (33-35). Can bodies of canned tuna were made by tin-plate, and used c-enamel or aluminium-paste as coating materials. In pH values of canned tuna, sample codes 1-10 (pH 5.55-5.69) and 19-27 (pH 5.17-5.85) were higher than sample codes 11-18 (pH 4.95-5.43) and 28-30 (pH 5.20-5.38). There was no difference in salinity (1.3-1.9%) and vacuum degree (15-18 mmHg) among canned samples. Heavy metal contents of canned seafoods ranged from 1.04-9.03 ppm for Sn, and 0.17-0.68 ppm for Pb. Those values are below the permitted range (less than 150 ppm for Sn and 2 ppm for Pb).

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.731-737
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• 1992

The specific attributes of aroma quality of canned tuna meat were investigated before and during refrigerated storage. Fresh, cooked tuna, beefy and meaty flavor notes of canned tuna meat were changed to card-boardy(1 week storage), oxidized fat-like(2 weeks storage), fatty acid-like and heavy oxidized fat-like(3 weeks storage), and then moldy and painty(4 weeks storage) flavor notes during storage in refrigerator at $4^{\circ}C.$ More than 126 peaks of volatile compounds collected from canned tuna meat were separated on Carbowax 20M capillary column of gas chromatographic analysis. Of the peaks, 54 compounds were identified by mass spectral data, matching $I_E$ values, and sniffing the effluent of each peak from GC detector. The contents of many low molecular weight compounds eluted with early retention times were decreased, whereas some other new compounds eluted with longer retention time were formed during storage. The compounds increased up to 3 weeks of storage and then decreased at extended storage time(4 weeks) were 1-penten-3-ol, 3-penten-2-ol, heptanal, limonene, 1-pentanol, octanal, 1-hexanol, nonanal, 2-octanone, 2-nonanone, 1-heptanol, benzaldehytde and some methyl substituted benzenes. p-Thiocresol, 2-chlorophenol, and 2-heptylthiophene were formed after 4 weeks of storage, but not detected in fresh canned tuna. Therefore, these compounds could be used as indicators for the quality changes during refrigerated storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.675-681
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• 1994

[ $F_0$ ]-values of the canned tuna in cottonseed oil (CTCO) were investigated under different sterilizing conditions to optimize the energy consumption and microbiological safety. The $F_0$-values were measured using a microcomputer based technique. The exact cold point was not the volumetric center of the cans, and it was located in the center of meat mass in can which had ca. $6\%$ of head space. Location of the test cans in retort showed no remarkable influence on the $F_0$-values when the cans were jumble loaded. The process time before sterilization should be shortened as much as possible to prevent the contamination of microorganisms. Thermophilic spore forming bacteria found from raw and precooked tuna were Bacillus subtilis, Bacillus cereus and Bacillus pasteurii, and the most heat resistant was Bacillus subtilis. The rational $F_0$-value for the CTCO obtained from the preservation test was regarded as 6min.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.287-295
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• 1996

To fulfill the requirements for establishing processes of canning low-acid foods, canned tuna packed in cottonseed oil (CTCO) sterilized at $110^{\circ}C$ for varying $F_0-values$ was subjected to microbial, sensory and chemical analyses. The investigation included the long-term quality stability of those products stored at $5^{\circ}C,\;25^{\circ}C\;and\;50^{\circ}C$ for 120 days. Longer sterilization $(F_0>5.18min)$ caused no remarkable changes in pH, amino nitrogen content, TBA value, POV and sensory scores of the CTCOs during storage at all experimental temperatures. But the sterilizing with $Fe\leq5.18min$ resulted generally poor quality in all experimental analyses. Consequently, $F_0-value$ 6.0 min may be applicable to sterilization of CTCO for long-term storage stability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.2
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• pp.211-215
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• 1989

The fatty acid composition of lipids separated from 14 kinds of canned fish and shellfish products from the market were examined. The crude lipid contents of canned fish and shellfish products showed wide difference (1.3-15.2%) depending on raw materials and kinds of products. Fatty acid composition of products were mainly consisted of polyenoic acid(34.5-61.4%), and followed by saturated acid(24.5-47.8%), monoenoic acid(12.4-32.0%). The major fatty acids were palmitic acid, palmitoleic acid oleic acid, eicosapentaenoic acid and docosahexaenoic acid. In case of canned tuna in oil and canned smoked oyster in oil, linoleic acid was the most predominant component(48.2%, 34.6%). Judging from the results, canned fish and shellfish products were abundant of the polyunsaturated fatty acids in spite of the high temperature sterilization and lone storage periods.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.306-312
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• 1984

In the present study, in succession to the previous reports, the sterilizing values ($F_0$) of the thermal processes for the canned minced hen-clams in brine and the canned smoked baby-clams in oil were determined ana discussed. The heat penetration tests were carried out three times with three cans at a time for each canned product. The thermocouple was setted on the can so as the tip of the applicaotor fixed on the position a little below the geometrical center of the can. The test cans were placed in the middle layer of the crate in which the same canned products were loaded with, and test cans were arranged to the front, the middle and the rear in the retort. The heat penetration curve obtained for the canned minced hen-clams in brine showed a broken logarithmic heating curve, while that of the canned smoked baby-clams in oil showed a simple logarithmic heating curve. The calculated $F_0$ values for the canned minced hen-clams in brine were 47.79 for No. 2 can, 52.99 for Ne. 7 can. and 45.21 for No. 2 tuna can, respectively. And the $F_0$ value for th canned baby-clams in oil packed into No. 3B square can was 14.12. Additionally, the nomographs represent the relationship between $F_0$ vlaues and B values (process time including $42\%$ of come-up time) for the each canned product were constructed.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.308-314
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• 2001

This study was conducted to determine the content of heavy metals in canned foods and soft drinks available on the Korean markets. Trace metals (Pb, Cr, Cd, and Sn) were detected in 24 kinds, 120 samples by Atomic Absorption Spectrophotometer. The average concentration of heavy metals in canned foods was in the order of Sn (6.930 ppm)>Cr (0.050 ppm)>Pb (0.030 ppm)>Cd (0.008 ppm), which was the same order in soft drinks as Sn (3.519 ppm)>Cr (0.080 ppm)>Pb (0.024 ppm)>Cd (0.001 ppm). The total contents of heavy metals in canned fruits and fruit juices were relatively higher than those in cans and drinks made of vegetable and fish. It can be supposed that the high acidity owing to the organic acid of fruit itself promotes to extract metals from can materials, and although fish usually contains more heavy metals than vegetables, canned fish revealed low level because internal organs and most of skin which had more heavy metals than meat were removed throughout canning process. Because processed foods such as canned foods and soft drinks are very popular with the children and adolescence according to the change of life style and eating habit, and the possibility of exposure to heavy metals by the habitual intake of these is increasing simultaneously, it is suggested that more practical study about the process of exposure and the amount in each step is needed fur the assessment of safety.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.68-74
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• 1999

The optimum conditions for selective .elimination of salt from tuna boiled extract (TBE) by electrodialysis were determined. The desalination conditions of TBE were determined at various pH's, concentrations and volumes of TBE. The ion-exchange membrane with a molecular weight cut off 100Da was used for desalting of TBE. The desalination times on $1\%$ and $10\%$ of TBE concentrations were 40 min and 240 min, respectively. The electrodialysis process could removed above $95\%$ of the initial salt content in $1\%$ and $10\%$ of TBE concentrations. The desalination of TBE at pH 4.0 was $14\%$ higher than that at pH 9.0 The amount of water transferred by the electrodialysis was determined. The electrodialysis process could remove above $90\%$ of the initial salt content in $5\%$ TBE for 80 min. The initial volume and the permeate did not have significant effects on desalination time and ratio. The key parameters for the desalination of TBE were pH and concentration of TBA.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.895-900
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• 1998

In order to the effective utility of marine by-product, crude lecithin was isolated from skipjack viscera oil and the lecithin was refined by bleaching and deodorization. Crude lecithin was separated from the skipjack viscera oil degummed with 0.4 ml of citric acid per 100 ml of the oil. Bleaching was effected by adding $5\%$ activated clay and treating for $40^{\circ}C$ for 90 min under vacuum, and deodorization was effectively conducted by steam distillation at $130^{\circ}C$ for 60 min under 4 ton of vacuum. The major fatty acids of the skipjack viscera oil. were 16:0. 18:1 (n-9), 22:6 (n-3), 18:0, and 16:1 (n-7). Crude and refined lecithins contained more aproximately $7\~18\%$ of 22:6 (n-3) than raw oil, the skipjack viscera oil.