• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1006-1012
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• 2004

We evaluated physicochemical and sensory characteristics of 25 commercial salt-fermented shrimps by kind (Oh Jeot, Yook Jeot and Chu Jeot) by manufacturer (traditional marketer (TS) ＆ company (CS)). Salinity and pH ranged 17.9∼28.7% and 7.82∼8.74, respectively, of which Chu Jeot was somewhat higher in salinity and pH, compared with those of the others. Amino nitrogen (AN), volatile basic nitrogen (VBN) and thiobarbituric acid reactive subjects (TBARS) showed great variation ranged with 21.41∼661.13 mg%, 263.2∼1180.2 mg% and 0.507∼1.322 $\mu\textrm{g}$/g, respectively. Hunter color of L value was 53.99∼67.45, a value, 4.98∼12.06 and b value, 4.45∼10.4. Physicochemical quality showed greater variations in Chu Jeot of TS than that of CS. Products of CS have higher salinity while lower VBN and AN than those of TS. Sensory results showed that mean scores of appearance, over-all taste, over-all flavor and over-all acceptability between TS and CS were not significantly different. The mean score of over-all acceptance was the highest in Yook Jeot. Physicochemical and sensory characteristics of salt-fermented shrimps in a PCA plot comprised of first principal component (68.36%) and second principal component (31.36%).

• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.173-180
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• 2022

There are a number of methods to evaluate the quality of squid. However, when purchasing the fish, consumers and retails rely only on the sensory test and flavor in the field. Therefore, this study was aimed to prove relationship between scientific indicator and sensory test. Total viable cell count (TVC), viable cell count of Pseudomonas spp., pH and volatile basic nitrogen (VBN) were selected as scientific indicators and mesured during the storage of squid at different temperature. The squid was storaged at 3 different temperature (5℃, 15℃, 20℃). Off flavor determination time was measured by R-index, and kinetic modeling was conducted. Activation energies of off-flavor determination time, TVC, Pseudomonas spp, VBN, and pH were 51.210 kJ/mol, 42.88 kJ/mol, 50.283 kJ/mol, 72.594 kJ/mol and 41.99 kJ/mol respectively. Activation energy of off-flavor determination time was approximated to viable cell count of Pseudomonas spp., TVC, pH and VBN as an order. Especially, viable cell count of Pseudomonas spp. had best match of the activation energy. Therefore, it was judged that indicator of off-flavor determine time was viable cell count of Pseudomonas spp..

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.51-56
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• 1997

Effects of mustard seed (Brassica juncea) on the preservation of soup for Naengmyon were investigated, and morphological changes of E. coli treated with extract of mustard seed were examined. Titratable acidity of soup for Naengmyon treated with mustard seed was higher than that of control at initial stage, but became lower than control after 24 hours of preservation. The number of bacteria and E. coli in soup for Naengmyon added with mustard seed was lower than that of control, and the more mustard seed was added, the less bacteria and E. coli were observed. The content of volatile basic nitrogen (VBN) increased during preservation of soup for Naengmyon. The VBN content of soup for Naengmyon added with mustard seed was higher than that of control, and the more mustard seed was added, the lower VBN was detected. Scanning eletron microscopys of E. coli treated with extract of mustard seed showed that cell surface was distorted with shrinked cell mass.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.427-432
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• 2005

The purpose of this study was performed as model study using four animals to investigate the correction between the changes in Differential Scanning Calorimetry thermogram of muscle proteins during storage and meat freshness. M. longissimus dorsi of pork was obtained immediately after slaughter and chilled/stored at either $-2^{\circ}C$ or $25^{\circ}C$ for up to 96 h for analyses. DSC thermograms were determined and compared with pH values, ATP-related compounds, K-values, volatile basic nitrogen (VBN) levels, bacterial counts and electrophoretic behavior. Changes in pH, bacterial counts, VBN and K-values were associated with increased storage temperature and time. The levels of pH values, bacterial counts, VBN and K-values of pork samples stored at $25^{\circ}C$ were higher than those of the pork samples stored at $-2^{\circ}C$. ATP concentration decreased faster in samples stored at $25^{\circ}C$. Only IMP increased in samples stored at $-2^{\circ}C$, whereas the concentration of hypoxanthine and inosine increased in samples stored at $25^{\circ}C$. One exothermic peak and two endothermic peaks appeared on the thermograms of pork stored at either temperature. Lower transition temperature of myosin, sarcoplasmic protein and actin peaks were observed. The freshness parameters of K-value, VBN and hypoxanthine showed highly negative correlations (-0.742- -0.9980) to the changes in transition temperature. Therefore, the shift temperature on DSC thermogram can be used as an indicator of the freshness parameters of meat.

• 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.49 no.2
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• pp.101-108
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• 2016

We investigated changes in the physiochemical quality of sailfin sandfish sauces fermented with two kojis during long-term storage at room temperature. Four fish sauces, including a control, were prepared by salt-fermentation with soybean koji (S-koji) or rice koji (R-koji) after autolysis. During storage, for 12 months, the color and levels of amino acids, total volatile base nitrogen (T-VBN) and organic acids but not moisture, salt or total nitrogen levels or pH differed markedly according to fish sauce type. The total nitrogen level was highest in S-koji, but there was no difference in the rate of increase in amino acid levels among the four fish sauces during storage. The T-VBN, of autolysis and S-koji were significantly higher than those of the control and R-koji during the entire storage period (P<0.05). The initial organic acid level did not differ among the four fish sauces, whereas it was notably higher in R-koji than in the other sauces at the end of storage. Hunter L, a and b values decreased in all fish sauces with increasing storage time. In conclusion, soybean koji may enhance the levels of nitrogen compounds as well as T-VBN in fish sauce, while rice koji reduced the formation of excess T-VBN and increased organic acid levels during storage at room temperature.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1564-1567
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• 2001

Hydrolysis of plant protein to non-protein nitrogen (N) or ammonia can reduce quality of silage crops. Heating or non-enzymatic browning is a treatment to inhibit this hydrolysis. This experiment was conducted to examine the effects of pre-heated soybean meal and molasses on the fermentation quality of napiergrass silage. The initial growth of napiergrass was harvested at 85 days of age and immediately chopped into about 1 cm length. About 700 g of the grass was ensiled into a laboratory silo (1.0 liter polyethylene container) and incubated for 30 days at room temperature ($28^{\circ}C$). No additives (control), molasses, soybean meal and molasses + soybean meal treatments were prepared. All additives were non-heated or heated in an oven at $150^{\circ}C$ for 30 minutes before ensiling. Molasses was added at 3% on the fresh weight basis and soybean meal was added at 0.5% N, respectively. After opening the silo, pH, total nitrogen (TN), volatile basic nitrogen (VBN), lactic acid (LA), acetic acid (AA), butyric acid (BA) and dry matter (DM) contents were determined. The data were analyzed statistically by analysis of variance. Compared with control, molasses addition significantly decreased pH value, VBN/TN, AA and BA and increased LA production. Soybean meal addition significantly increased TN and VBN/TN of silage. Both molasses and soybean meal addition significantly reduced pH value, AA, and BA and increased DM and LA contents of silage. The heating of additives was only effective to reduce VBN/TN production compared with non-heated additives in soybean meal and soybean meal with molasses addition.

• Korean Journal of Organic Agriculture
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• v.21 no.2
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• pp.219-232
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• 2013

The relevant main constituents of rosemary are compound of a vast number of polyphenolics, including carnosic acid, carnosol, rosmarinic acid, and ursolic acid. Recently, phenolic compounds of plant origin have attracted considerable attention due to their beneficial functional and nutritional effects including antioxidant and antibacterial activity. This study was carried out to investigated effect of carnosic acid on pH, thiobarbituric acid reactive substance (TBARS), volatile basic nitrogen (VBN), 2,2-diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity, and total bacteria counts in white sausage during the storage at room temperature. Addition of carnosic acid was decreased of pH, TBARS, VBN, and enhanced antioxidant and antibacterial activity in white sausage. These activities increased with increasing concentrations of carnosic acid. Furthermore, the potent antibacterial activities of carnosic acid against pathogenic bacteria (Escherichia coli KCCM 11234 and Salmonella enteritidis KCCM 12021) were measured. Carnosic acid showed noticeable inhibitory effects on E. coli and S. enteritidis. In conclusion, carnosic acid might be used as a natural preservative in white sausage.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.158-162
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• 2006

To determine freshness and quality change of tofu during storage, we manufactured a freshness indicator and monitored the surface pH, volatile basic nitrogen (VBN), thiobarbituric acid reacted substance (TBARS), total bacterial counts, and sensory evaluation. Tofu had a change in color of the freshness indicator after storage of 8 days at $4^{\circ}C$, and its pH and total bacterial counts reached 5.6 and 7.63 log CFU/g, respectively. VBN and TBARS values increased and reached the decay point at the time of color change of the freshness indicator. Sensory evaluation also indicated that samples were unacceptable by off-odor and decrease of firmness at day 8 of storage. These results suggest that a freshness indicator should be useful in determining expiration date of tofu products during marketing by indicating the microbial safety as well as sensory change.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.285-291
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• 2003

The effects of carcass grade(B and E) and containing mugwort powder(0.3％) on the pH, volatile basic nitrogen(VBN), thiobarbituric acid reactive substances(TBARS), bacterial count and residual nitrite of the pork sausage were investigated during storage at 4$^{\circ}C$${\pm}$1 for 8 weeks. The pH value and VBN content of sausage containing mugwort powder were not significant different(p＞0.05) depending on the carcass grade as compared to sausage free of mugwort powder. The TBARS values of sausage containing mugwort powder were significantly lower than those of sausage free of mugwort powder up to 8 weeks of the chilling process. The sausage containing mugwort powder showed to have lower bacterial counts and residual nitrite contents than those free of mugwort powder depending on the carcass grade. However, those of sausage were not affected by the carcass grade.