Dental plaque biofilms cause various dental diseases; therefore, inhibiting the growths of the dental plaque bacteria which produce biofilms can be a strategy for preventing dental disease. Certain sulfated polysaccharides from marine algae exert antimicrobial activities against human bacterial pathogens in addition to their physiological benefits. On the basis of these observations, the antimicrobial and antibiofilm activities of sulfated polysaccharides from different marine algae were evaluated against dental plaque bacteria. Among the sulfated polysaccharides, a fucoidan from Fucus vesiculosus showed notable antimicrobial activities against the selected dental plaque bacteria, including some foodborne pathogenic bacteria. The minimum inhibitory concentrations were of 125 to 1000 µg mL−1. Regarding the antibiofilm activity, the fucoidan at the concentrations of above 250 µg mL−1 completely suppressed the biofilm formations and planktonic cell growths of Streptococcus mutans and S. sobrinus. However, no eliminative effect on the completed biofilm was observed. The fucoidan consisted of almost fucose base polysaccharide containing approximately 14.0% sulfate content. The average molecular weight of the fucoidan was changed by heat treatment (121 °C for 15 min) and it affected the antimicrobial activity.

To find an economic use of red snow crab (Chionoecetes japonicus) shell waste, we focused on its high mineral content. To evaluate its usability as a coagulant for tofu making, the effects of the crab shell extracts on the textural and sensorial properties of the tofu samples were investigated. The crab shell powder (CSP) and ash (CSA) were used for their extract preparation, and 1%–5% acetic acid treatment led to an abundance of calcium in the resulting extracts. The tofu yields of all the acetic acid extracts were comparable with those of the commercial coagulants MgCl2 and glucono‐δ‐lactone (GDL). Furthermore, the results for the textural attributes and sensorial acceptability demonstrated that either the extract from CSP prepared with 3% acetic acid or the extracts from CSA prepared with 1% or 3% acetic acid could be used as coagulants, because all the values of the extracts were statistically equivalent to those of the MgCl2 and GDL (p < 0.05).

This study investigated changes in the quality of fermented red snow crab Chionoecetes japonicus sauce with or without Aspergillus kawachii koji and added salt. Samples were divided into four groups depending on whether koji was added and the amount of salt: RC15, 15% added salt, no koji; RC20, 20% added salt, no koji; RK15, 15% salt plus 10% koji; and RK20, 20% salt plus 10% koji. The samples were fermented at 20±2℃ for 4 months. During the fermentation period, the moisture contents of the four types of sauce decreased while the crude ash and protein contents increased. The pH of the RK groups decreased and was lower than in the RC groups. The acidity of the RK groups increased and was higher than in the RC groups. Both the total nitrogen (TN) and amino nitrogen (AN) levels increased continuously and were higher in the RK groups than in the RC groups. The volatile basic nitrogen (VBN) content increased rapidly and was higher in the RC groups than in the RK groups. The color did not differ significantly among the four groups. The viable cell counts in the four groups increased and no coliforms were detected. The total free amino acid and glutamic acid contents were highest in the RK15 group and the main amino acids in RK15 were aspartic acid, glutamic acid, alanine, leucine, phenylalanine, and lysine. Overall acceptance was significantly higher for the RK groups than the RC groups and RK15 ranked highest among the four sauces. These results suggest that Aspergillus kawachii koji is beneficial for processing fish sauce made using red snow crab.

This study investigated the effects of freezing storage temperature and thawing time on the separation of leg meat of the red snow crab Chionoecetes japonicus. Crabs were stored at -20, -30, -40, or -50°C for 2 days and thawed for either 5, 10, 20, 30, or 40 seconds. While thawing, there were no significant differences in pH or acidity among the experimental groups, while the volatile basic nitrogen content increased continuously. The redness of samples stored at -20°C was higher than that of the other groups. The overall acceptance of samples stored at -20°C was also the best. These results demonstrate that no-heating methods may be useful for separating red snow crab leg meat.

This study investigated the physicochemical and sensory characteristics of fish paste containing red snow crab Chionoecetes japonicus leg-meat powder (RMP) in 0, 3, 6, 9, and 12% concentrations. The moisture contents of fish paste with RMP ranged from 56.7 to 60.2% and the pH ranged from 7.0 to 7.7. The L values decreased as the RMP concentration increased, and a and b increased. The folding test for all of the fish paste samples scored AA, which indicates good flexibility. The hardness, springiness, gumminess, and cohesiveness increased with the RMP concentration. In the sensory evaluation, the fish paste prepared with 6% RMP was the most preferred. These results suggest that RMP can be added to fish paste to achieve high quality.Key words: Red snow crab, Fish paste, Crab leg-meat powder, Chionoecetes japonicus This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Total 100.0 100.0 100.0 100.0 100.0 1 CON, fish paste added amount 0% of red snow crab meat powder; 3 RCP, fish paste added amount 3% of red snow crab meat powder; 6 RCP, fish paste added amount 6% of red snow crab meat powder; 9 RCP, fish paste added amount 9% of red snow crab meat powder; 12 RCP, fish paste added amount 12% of red snow crab meat powder.2 RMP, red snow crab leg-meat powder AA . 색도 조직감 및 절곡검사 관능검사