• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.3
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• pp.283-291
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• 2006

This study examined the development of a low-salt fermented seafood product using an ascidian (Halocynthia roretzi), and the optimum processing conditions and quality characteristics of the low-salt fermented ascidian (LSA). The optimum processing conditions for the LSA were as follows. The ascidian was shelled and its muscle sliced into 5 mm widths. This was soaked in a 10% salt and 1% sodium erythorbate solution for 20 min. The solution was drained and then the muscle was soaked in 0.1% sodium bisulfite solution for 1 min. To this was added a 1:1 mixture of anchovy sauce and rice gruel, and it was fermented at $5^{\circ}C$ for 15 days. The moisture content and salinity of the LSA were 75.0-75.4% and 8.0-8.5%, respectively. During salt-fermentation at $5^{\circ}C$ for 20 days, the amino-N content of the LSA increased, and the texture softened gradually. The viable cell counts in early salt-fermentation were $4.2-4.5{\times}10^4CFU/g$, and this decreased gradually. The ratio of saturated fatty acids tended to increase in early salt-fermentation, while that of polyunsaturated fatty acids decreased slightly. Chemical experiments and sensory evaluation showed that the dipping treatment in 1% sodium erythorbate solution and 0.1% sodium bisulfite solution resulted in a good color and prevented browning of the salt-fermented ascidian meat. Moreover, adding anchovy sauce and rice gruel mixture improved the flavor of the LSA.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.141-150
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• 2011

In order to elucidate a flavor characteristics of the low-salt fermented ascidian (LFA), a volatile flavor constituents were extracted and analyzed by SDE apparatus and GC/MS. Salinity, pH and volatile basic nitrogen of the LFA were 8.0%, 5.17 and 23.0 mg/100 g, respectively. Total content of volatile flavor compounds identified from the LFA was $1,221.42{\mu}g/100g$ as cyclohexanol (internal standard), it were composed of 23 alcohols ($644.85{\mu}g/100g$) such as 1-octanol and 2-pentanol, 16 acids ($293.91{\mu}g/100g$) such as 2-hydroxy-propanoic acid and butanoic acid, 15 aldehydes ($153.61{\mu}g/100g$) such as trans-2-hexanal and benzaldehyde, 29 hydrocarbons ($97.65{\mu}g/100g$) such as 1,4-dimehyl-cyclooctane and 1-nonene, six aromatic compounds ($6.20{\mu}g/100g$), two esters ($2.07{\mu}g/100g$), two nitrogen-containing compounds ($19.09{\mu}g/100g$) and three micellaneous compounds ($4.04{\mu}g/100g$).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.273-280
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• 2020

Volatile compounds in fermented ascidians Halocynthia roretzi were analyzed to identify key flavor compounds using SPME/GC/MSD (solid phase microextraction/gas chromatography/mass selective detector) after 60 days of fermentation at 5℃. The control was chopped ascidians subject to anti-browning and 4% salt treatment. product A was made from product C by adding an alcohol extract of red peppers and onion peel, 0.1% of glucose, and 0.55% of mixed amino acids (MAA; 0.05% Glu, 0.1% Pro, 0.3% Ala, and 0.1% Gly). After blanching and anti-browning treatment of chopped ascidians, Product B1 was made by adding 3% anchovy sauce and 6% sorbitol. Product B2 was made by adding 0.1% glucose and 0.55% MAA to Product B1. In total, 78 compounds were identified, including 31 alcohols, 15 aldehydes, and 10 ketones. The alcohols included 12 compounds from the C8-C10 series with floral and fruit odors, including octanol, 3-methyloctanol, 2,6-dimethyl-1-heptanol, (E)-5-octen-1-ol, 6-methyloctanol, (E)-3-octen-1-ol, (E)-3-decen-1-ol, (Z)-1,5-octadien-3-ol, and nonanol. These were detected in high amounts in ascidians and all fermented products. Aldehydes (octanal, (E)-2-octenal, 2,4-heptadienal, and nonanal) and ketones (1-oten-3-one and 2-heptanone) with fatty and mushroom odors were detected as major compounds, whereas nine ethyl esters were detected only in product A.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.4
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• pp.330-339
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• 1993

To optimize the processing conditions of fermented ascidian, Halocynthia roretzi, fermentation at low temperature with different salt contents, the effect of enzymes added, and the quality changes during fermentation were investigated. As the quality factors, changes in such components as free amino acid, volatile basic nitrogen(VBN), amino nitrogen, total creatinine, total carotenoid, extents of browning, reducing sugar and glycogen were determined. The quality was also evaluated organolatically by pannel test. Fresh deshelled and sliced ascidian were fermented for 50 days at $5{\pm}1^{\circ}C$ with different salt contents of 5, 10, $15\%$ (w/w) with enzyme contents of papain $0.1\%$ and protease-A $0.1\%$ VBN increased gradually during the 50 days of fermentation and showed $30{\sim}40mg/100g$ at 30, 35 and 45 days in case of salt contents 5, 10 and $15\%$ added with $0.1\%$ papain and protease-A, respectively. Amino nitrogen and the total creatinine increased until 20 days, hereafter tended to decrease gradually. Total carotenoid and glycogen also decreased during the fermentation. The results of sensory evaluation of fermented ascidian at $5{\pm}1^{\circ}C$ added $0.1\%$ papain or protease-A showed that the peculiar taste and flavor of ascidian was sustained for $30{\sim}40$ at least 20 days with $5\%$ NaCl and $35{\sim}45$ days of fermentation with 10 and $15\%$ NaCl.