• Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.237-242
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• 2013

We investigated the antioxidant and angiotensin I converting enzyme (ACE) inhibitory activities of red snow crab Chionoecetes japonicas shell (RSCS) hydrolysate by enzymatic hydrolysis and its molecular weight cut-off fractions. The RSCS hydrolysate was fractionated through two ultrafiltration membranes of 3 and 10 kDa cut-offs. Three fractions (<3 kDa, 3-10 kDa, and >10 kDa) were evaluated for total amino acid composition, antioxidant activities using 2'-azino-bis[3-ethylbenzthiazoline-6-sulfonic acid] ($ABTS^+$) radical scavenging and superoxide dismutase (SOD)-like activities and reducing power assays, and ACE inhibitory activity using Hou's method. Although all fractions showed activity, the <3 kDa fraction of RSCS hydrolysate exhibited the greatest $ABTS^+$ radical scavenging, SOD-like and ACE inhibitory activities. However, these fractions exhibited low reducing power. These results suggest that the low-molecular-weight enzymatic hydrolysate of RSCS could be used as a functional ingredient to control oxidative stress and ACE activity.

• Culinary science and hospitality research
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• v.23 no.2
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• pp.56-63
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• 2017

In this study, we evaluated physicochemical properties and sensory characteristics of teriyaki sauce made by using the shell, the byproduct of red snow crab. Moisture content was the highest in fried FRC and the lowest in immersed SOC- while viscosity exhibited contrary tendency. The pH was the highest in dried DRC and the lowest in untreated RAC. Chromaticity was the highest in fried FRC for L, a, and b values altogether. Such result was considered attributable to elution of astaxanthin, a fat-soluble dye protein, which affected chromaticity while it underwent pre-treatment by being fried. Salinity was the highest in fried FRC and lowest in immersed SOC. Available solid contents exhibited contrary tendency. The total free amino acid content was the highest in immersed SOC and the lowest in untreated RAC. Contents of essential amino acids and tasty amino acids, the free amino acids, were the highest in SOC, suggesting that savory taste manifested the most noticeably among specimens treated differently by varying methods. The results of preference test showed that SOC, which showed the highest free amino acid content, also showed the highest preference in terms of outwards appearance, fragrance, taste, texture, and overall items of preference. Those results suggested that the immersion of red snow crab shell increased elution of available solid content and tasty components, influencing the preference of overall taste of teriyaki sauce positively, concerning pre-treatment methods. Based on overall results of the experiment in this study, pre-treatment involving immersion would lead to production of teriyaki with excellent nutrition and sensory features in connection with the use of red snow crab shell for manufacturing teriyaki.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.88-93
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• 2003

NIR spectroscopic analysis was used for the measurement of deproteinization and deacetylation to apply the merits of NIR spectroscopic analysis to the quality management in the process of chitin and chitosan production. In measuring squid pen and red snow crab shell, which are raw materials of chitin and chitosan by NIR there were typical peaks in 1200 nm, 1510 nm, 2050 nm and 2180 nm. Squid pen had somewhat higher peak than red snow crab shell. In producing chitin, amount of protein was decreased. Measuring it by NIR, reduction of protein caused by deproteinization was identified in producing chitin. Chitosan is a derivative material made from chitin by processing the deacetylation. During this processing, acetyl groups were removed and amide bends were appeared. From NIR spectra, peaks at 1530 nm and 2030 nm indicated amide II peak of chitosan, and these peaks were used for identifying the differences of structure between chitin and chitosan. The error in measurement of nonidentified sample was below $1\%$ and the error in the standard curve was below 0.006. These errors were very low and the accuracy of NIR was considered to be superior to the existing methods.