• Food Science of Animal Resources
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• v.38 no.4
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• pp.664-678
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• 2018

This study was carried out to establish shelf life for pork cutlet of ground meat and pork lard by using various quality indicators and to understand how quality changes in these products are accelerated by temperature. The samples were selected and purchased from markets in Korea, and the chosen quality indicators were total aerobic counts and coliform group in microbiological analyses, thiobarbituric acid reactive substances assay, volatile basic nitrogen, pH, acid value, and peroxide value in physical chemical analyses, and sensory evaluation. The pork cutlet samples were stored at $-18^{\circ}C$, $-6^{\circ}C$, and $-1^{\circ}C$, whereas pork lard samples were stored at $10^{\circ}C$, $25^{\circ}C$, $35^{\circ}C$, and $45^{\circ}C$. These temperature conditions were set to real distribution conditions. The samples were then analyzed using various models including of reaction orders, arrhenius equation, and $Q_{10}$ value. The quality limits for each sample were calculated, and shelf life was estimated. The results of this experiment highlighted the importance of temperature control during the distribution process of these products and revealed that temperature is a useful parameter for the establishment of a basic database for shelf life.

• Preventive Nutrition and Food Science
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• v.16 no.3
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• pp.253-260
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• 2011

This study was performed to investigate the physical, chemical and microbial characteristics of Gwamegi to provide basic data for the standardization of marine processed foods and for the improvement of the quality of commercial Gwamegi. The acid values of commercial Gwamegi were 5.8, 5.3 and 5.2 mg KOH/g for fillet type (F-type), "two divide" type (T-type) and whole type (W-type), respectively, and the peroxide values were 51.6, 51.5 and 53.2 meq/kg for each. There was a positive correlation between the acid value and the peroxide value (r=0.555) at confidence intervals (CI) of 99%. Trimethylamine (TMA) content of F-type, T-type and W-type products were 2.9, 2.6 and 3.6 mg%, respectively, while volatile basic nitrogen (VBN) contents were 22.4, 21.5 and 21.8 mg%. There was a strong positive correlation between TMA and VBN (r=0.961) at a CI of 99%. The histamine content was detected to be as much as 122 mg/kg, with about 36 % of the samples exceeding the CODEX criteria for histamine of 100 mg/kg. The total microbial count of 4 products exceeded 5 Log CFU/g and coliform group of 11 products exceeded the criteria of less than 1 Log CFU/g. Staphylococcus aureus in 27% of the samples exceeded the criteria of less than 2 Log CFU/g.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.647-655
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• 2018

This study collected basic data on two types of canned roasted oyster Crassostrea gigas. Oysters Crassostrea gigas were immersed at $105^{\circ}C$ for 6 min and then washed and dehydrated before pre-drying. Roasted oysters were prepared by baking boiled oysters at $140^{\circ}C$ for 20 min. The canned roasted oyster added with tomato sauce was prepared as follows. An aluminum can was filled with 50 g of roasted oyster and 40 g of mixed seasoning sauce, degassed at $90^{\circ}C$ for 3 min and vacuum-sealed using a double seamer under a 20 cmHg vacuum. The canned roasted oyster added with tomato paste sauce was prepared similarly by adding the same amount of tomato paste sauce instead of tomato sauce. Microbial growth, appearance, proximate composition, pH, volatile basic nitrogen (VBN), thiobarbituric acid (TBA) value, amino-N, salinity, color value, texture, free and total amino acids, and minerals were measured in the two products. A sensory evaluation indicated that the canned roasted oyster added with tomato paste sauce had preferable characteristics over the canned roasted oyster sauce added with tomato sauce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.644-654
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• 2015

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.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.713-722
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• 2011

The aim of this study was to confirm Pseudomonas spp. as the specific spoilage organism (SSO) of chilled beef during aerobic storage and to establish a model to predict the shelf life of beef. Naturally contaminated beef was stored at $4^{\circ}C$, and the spoilage limit of Pseudomonas organisms was determined by measuring several quality indicators during storage, including the number of Pseudomonas organisms, total number of bacteria, total volatile basic nitrogen (TVBN) values, L value color scale scores and sensory evaluation scores. The beef was then stored at 0, 4, 7, 10, 15 or $20^{\circ}C$ for varying amounts of time, and the number of Pseudomonas organisms were counted, allowing a corresponding growth model to be established. The results showed that the presence of Pseudomonas spp. was significantly correlated to each quality characteristic (p<0.01), demonstrating that Pseudomonas spp. are the SSO of chilled beef and that the spoilage limit was $10^{8.20}$ cfu/g. The Baranyi and Roberts equation can predict the growth of Pseudomonas spp. in beef, and the $R^2$ value of each model was greater than 0.95. The square root model was used as follows, and the absolute values of the residuals were less than ${0.05:\;{\mu_{max}}^{1/2}$ = 0.15604 [T+(-0.08472)] (p<0.01), $R^2$ = 0.98, $\lambda^{-1/2}$ = 0.0649+0.0242T (p<0.01, $R^2$ = 0.94). The model presented here describes the impact of different temperatures on the growth of Pseudomonas spp., thereby establishing a model for the prediction of the shelf life of beef stored between 0 to $20^{\circ}C$.

• Preventive Nutrition and Food Science
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• v.13 no.1
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• pp.45-50
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• 2008

The effect of aqueous chlorine dioxide ($ClO_2$) treatment on microbial growth and quality of chicken leg during storage was examined. Chicken leg samples were treated with 0, 50, and 100 ppm of $ClO_2$ solution and stored at $4^{\circ}C$. Aqueous $ClO_2$ treatment significantly decreased the populations of total aerobic bacteria, yeast and mold, and coliforms in chicken leg. One hundred ppm $ClO_2$ treatment reduced the initial populations of total aerobic bacteria, yeast and mold, and coliforms by 0.93, 1.15, and 0.94 log CFU/g, respectively. The pH and volatile basic nitrogen values in the chicken leg decreased with increasing aqueous $ClO_2$ concentration, while concentrations thiobarbituric acid reactive substances (TBARS) increased during storage regardless of aqueous $ClO_2$ concentration. Sensory evaluation results revealed that the quality of the chicken leg treated with aqueous $ClO_2$ during storage was better than that of the control. These results indicate that aqueous $ClO_2$ treatment can be useful for improving the microbial safety of chicken leg during storage.

• The Korean Journal of Food And Nutrition
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• v.19 no.1
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• pp.47-52
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• 2006

This study was carried out to improve the preservation and the functionality of chicken legs. Three precipitation solutions of common solution(A), herb solution(B) and herb solution containing chitosan(C) were prepared. The chicken legs were treated with A, B and C solution, respectively, during 4 hours. And the chicken legs treated with each solution were stored at $7^{\circ}C$ for 8 days. The quality changes of each groups were examined by pH, total bacteria, VBN(volatile basic nitrogen) values and sensory evaluation. The pH values of three groups were not different. Chicken legs treated with C solution showed the lowest VBN values and total bacteria cell count and the highest sensory scores in color and flavor.

• Food Science of Animal Resources
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• v.38 no.2
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• pp.338-349
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• 2018

The objective of this study was to investigate comparison of physicochemical, microbiological, and sensory characteristics of Hanwoo eye of round by various packaging methods [wrapped packaging (WP), modified atmosphere packaging (MAP), vacuum packaging (VP) with three different vacuum films, and vacuum skin packaging (VSP)] at a small scale. Packaged Hanwoo beef samples were stored in refrigerated conditions ($4{\pm}1^{\circ}C$) for 28 days. Packaged beef was sampled on days 0, 7, 14, 21, and 28. Physicochemical [pH, surface color, thiobarbituric acid reactive substances (TBARS), and volatile basic nitrogen (VBN) values], microbiological, and sensory analysis of packaged beef samples were performed. VP and VSP samples showed low TBARS and VBN values, and pH and surface color did not change substantially during the 28-day period. For VSP, total viable bacteria, psychrotrophic bacteria, lactic acid bacteria, and coliform counts were lower than those for other packaging systems. Salmonella spp. and Escherichia coli O157:H7 were not detected in any packaged beef samples. A sensory analysis showed that the scores for appearance, flavor, color, and overall acceptability did not change significantly until day 7. In total, VSP was effective with respect to significantly higher $a^*$ values, physicochemical stability, and microbial safety in Hanwoo packaging (p<0.05).

• Applied Biological Chemistry
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• v.44 no.2
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• pp.81-87
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• 2001

Oyster jeot-gal were prepared in the form of salt-fermented oyster and oyster in soy sauce tentatively and used for investigation the retarding effect of its fermentation in a vacuum from the physicochemical and microbiological points of view. $_PH$ value decreased slightly but amino-N (AN) and volatile basic nitrogen (VBN) increased inversely during the fermentation periods. AN contents were greater in vacuum fermentation than in non-vacuum, whereas VBN were greater in non-vacuum. Total viable cell counts were similar to trend of gentle decrement after increment to some degree but showed higher in non vacuum than in vacuum. In vacuum product, total amino acid contents increased with the elapse of fermentation days or in time of reduction those were higher than in non-vacuum. On the results of chemical analysis, it showed that fermentation was delayed in vacuum and that vacuum fermentation was effective for the shelf-life extension of jeot-gal.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.308-315
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• 2020

To obtain a value-added product from the non-toxic brown-backed toadfish Lagocephalus gloveri (pufferfish), we developed a retort pouched pufferfish soup (RPS) and characterized its processing conditions and quality metrics. We found that the most appropriate manufacturing process for the RPS consisted of detoxifying and cold-water dipping the pufferfish flesh, blanching it, and adding it to the retort pouch along with other ingredients (hot-water extract of pufferfish head and carcass, radish, bean sprouts, and garlic), after which the pouch was sealed, sterilized (120℃, F₀ value 7.5-10 min.), cooled, and inspected. The moisture, crude protein, and total volatile basic nitrogen contents of the RPS were 97.2%, 1.3% and 7.7 mg/100 g, respectively. The total free amino acid content was 903.2 mg/100 g, and the main free amino acids were glutamic acid, taurine, lysine, glycine, threonine, alanine, arginine, proline, and hydroxyproline. Sterilizing the RPS for up to F₀ value 10 min. did not cause any major problems in terms of chemical or sensory qualities. This RPS has good storage stability and organoleptic qualities compared with similar commercial pufferfish soups and is suitable for commercialization as a value-added instant seafood soup.