• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.135-137
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• 2005

A PC-based automatic system was developed for automatic titration in volatile basic nitrogen analysis by the microdiffusion method. The system used a CCD-type PC camera for the automatic detection of the titration end point. The camera checked whether the green value of a pixel on the red image of titrated solution became greater than the red value. The data from the automatic titration using the system were not significantly different (p>0.05) from those taken by manual titration. The agreement between means of data from manual titration and those from automatic titration was good.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1051-1057
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• 1999

The effects of gamma irradiation on taste compounds of low salted and fermented squid were investig ated. Salted and fermented squid products were prepared with salt concentrations of 5%, 10%, and 20% and was fermented at 15oC and 25oC after gamma irradiation with a dosage of 2.5~10 kGy. Amino nitrogen (AN), volatile basic nitrogen(VBN), trimethylamine(TMA), and hypoxanthine(Hx) contents were examined during the fermentation periods. Results showed that gamma irradiation had no effect on the initial con tents of AN, VBN, TMA, and Hx compared with non irradiated salted and fermented squid. During the fermentation periods, these contents rapidly increased in accordance with the decrease in NaCl concen tration and irradiation dose, and the increase in fermentation temperature. Specifically, the taste compounds of salted and fermented squid prepared with a NaCl concentration of 10% and an irradiation dose of 10 kGy maintained the appropriate level for the fermentation period at 15oC.

• Food Science of Animal Resources
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• v.22 no.2
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• pp.158-163
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• 2002

The Korean fresh pork loins in vacuum packaged were obtained from three different Korean export companies and investigated for meat color, TBARS(thiobarbituric acid reactive substance) and VBN(volatile basic nitrogen). The fresh pork loins were stored at 2$^{\circ}C$ for 50 days and analyzed with an interval of 5~10 days. The L* values of meat from the company II and III were relatively higher than those from the company I. The L* values of loins from the companies II and III were increased until 35 days of storage and decreased after that period. The TBARS values were increased as the storage time increased for meat from all companies. Although the TBARS values of all loins were similar at the beginning stage of storage, those from the companies II and III were higher than loins from the company I after 40 days of storage. There were no significant difference in VBN among loins from three companies during the storage.

• Journal of Life Science
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• v.27 no.9
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• pp.1011-1019
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• 2017

This study examined the influence of sea wind mugwort extract treatment on quality characteristics of mackerel during storage. Mackerel were packaged individually and then immersed in 5% sea wind mugwort extract for 2, 3, or 4 hr and stored at $-20^{\circ}C$. The salinity of a control (no treatment) and that of mackerel immersed in sea wind mugwort for 2 hr was lowest (0.07%). pH of 5.90-6.23, and the change in acidity was in the opposite range. Immersion for 2, 3, and 4 hr led to a decrease in the tensile strength of the samples following storage, whereas the tensile strength of the control increased. The volatile basic nitrogen (VBN) content of the mackerel immersed for 2 hr was significantly lower than that of the control (5.6-15.4 mg% vs. 4.2-50.7 mg%). In the mackerel immersed for 2 hr, the total polyphenol and total flavonoid content was 286.3-497.0 mg gallic acid equivalents (GAE)/100 g and 177.5-385.6 mg quercetin equivalents (QE)/100 g, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethyl-benzothizoline-6-sulfonic acid) (ABTS) radical scavenging activities of the mackerel immersed in sea wind mugwort for 2 hr were 50.6% and 61.3%, respectively. Overall, the immersion of mackerel in sea wind mugwort for a short time significantly improved quality characteristics, such as salinity, pH, acidity, hardness, antioxidant activity, and perceptible quality, following storage.

• Korean journal of food and cookery science
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• v.26 no.5
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• pp.567-574
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• 2010

Pork patties were formulated with either steam-dried green tea power or freeze-dried raw tea leaf powder, and the quality characteristics of these products were monitored. Proximate analysis of tea powder contained 17.80~19.85%, 4.70~5.73%, and 5.60~5.77% (as is) crude protein, crude fat, and crude ash, respectively. There were no significance differences in pH among the samples. Chromaticity tended to decrease brightness ($L^*$) and redness ($a^*$), and there were significant differences in yellowness ($b^*$) as the added amount of tea power was increased. For texture, hardness increased as more green tea powder was added. Thiobarbituric acid reactive substances (TBARS) and volatile basic nitrogen (VBN) values increased after storage for 12 days, whereas samples formulated with green tea powder showed lower TBARS and VBN values compared to control groups. Sensory panelists showed preference for samples with green tea powder added compared to the control group.

• Korean Journal of Poultry Science
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• v.23 no.4
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• pp.203-207
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• 1996

This experiment was carried out to find out the effects of packing methods on shelf-life and hy-giene of breast and thigh meats in chicken. The carcass weights were about 1.6 kg per bird, and chilled by air spray method. The breast and thigh meats were packed by either vacuum or atmosphere packing methods. Samples were analyzed at 1, 4, 8, 12 and 16 wk after quick freezing at -45˚C for 35 min. Regardless of packing method. The thiobarbituric acid(TBA) values of thigh meats after 1 wk of storage were higher than those of breast meats. The TBA values of both treatments were increased as storage period extended. In addition, the TBA values of vacuum packed meats were lower than those of atmosphere packed meats. The VBN(volatile basic nitrogen) values, regardless of packing method, at 1 wk of storage were higher than those of breast meats. The VBN contents of breast and thigh meats after 16 wk of storage increased markedly, but failed to show significant difference between the two packaging methods. Total plate counts of breast and thigh meats were increased gradually as storage period extended, and the total plate count of breast meat was higher than that of thigh meat. The coliform bacteria were not detected until 16 wk after storage.

• Korean Journal of Poultry Science
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• v.24 no.1
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• pp.9-15
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• 1997

This experiment was carried out to investigate the effects on shelf-life of chilling and packing methods of cold chicken breast and thigh meats. Deboned chicken breast and thigh meats were packed by either vacuum or atmosphere packing method, and stored at -2˚C for 1, 3, 7, 11, 15, and 20 days. The thiobarbituric acid(TBA) values of all treatments were significantly increased as the storage period extended(P<0.05), however, TBA values of all treatments were remark-ably decreased at 15 days. TBA values of immersion chilled and vacuum-packed thigh meats were increased, but no difference between atmosphere and vacuum-packing methods was found. The volatile basic nitrogen(VBN) values at 1 day of storage were low, but they were increased as the storage period extended. The VBN values at 20 days after storage were from 12.25~19.28 mg %. Total bacterial counts tended to increase in all treatments, however, no significant difference was found in any treatment. Total plate counts of breast meat were higher than those of thigh meat as the storage period extended.

• Korean Journal of Veterinary Service
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• v.40 no.4
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• pp.245-251
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• 2017

Cold air or ice water are used to chill poultry carcasses after slaughter. In order to compare the microbial reduction effect of two different chilling systems in poultry carcasses, Pre-and post-chilled carcass samples were tested for contamination agents such as aerobic bacteria counts, E. coli counts and Salmonella spp. counts. Water chilling system showed higher reduction ratio of bacteria than air chilling system during the three seasons. Also, aging of slaughter facility was related with bacterial contamination of pre-chilld carcasses. And additional volatile basic nitrogen (VBN) test were conducted in poultry packing meats and it increased steadily during 15 days. VBN at 8~9 days were over 13 mg% with putrid smell. Poultry packing meats by water chilling system were fresher than air chilling system during early storage time. But those decayed faster after 9 days.

• Food Science of Animal Resources
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• v.18 no.3
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• pp.240-247
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• 1998

This experiment was carried out investigate changes in proximate composition, pH, volatile basic nitrogen (VBN), thiobarbituric acid value (TBA) and mineral contents of pure Kaesojoo (PK) and Kaesojoo added medicinal herbs (KMH) during storage period (30 days) at 4$^{\circ}C$ and -18$^{\circ}C$. Two dogs with 12kg live weight were slaughtered to obtain samples from extracts. The results obtained were as follows: Crude fat and ash of KMH were higher than those of the PK, but the moisture and crude protein was higher in the PK (p＜0.001). Proximate composition did not affect cold and frozen storage and storage period. the pH of the PK through all periods. The VBN value of all treatment gradually increased during storage period. That of KMH tend to be lower than PK, all treatment was maintained freshness. The TBA value of all treatment gradually increased during storage period (p＜0.05). Cold storage and PK tend to be higher frozen storage and KMH. Among minerals Ca, K, Mg, Na, P contents of the KMH were higher than those of the PK and the Ca, Mg, Zn contents were significantly changes (p＜0.05) according to the storage period and temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1317-1324
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• 2015

The objective of this study was to examine both antioxidant activities and quality characteristics of sausages made from a mixture of purple sweet potato powder and pigment. Five sausages were manufactured: F0 (control), F1 (0.15%-sodium nitrite), F2 (0.2%-purple sweet potato pigment), F3 (0.2%-purple sweet potato pigment and 5%-purple sweet potato powder), and F4 (0.2%-purple sweet potato pigment and 10%-purple sweet potato powder). Sausages were stored at $4{\pm}1^{\circ}C$ for 30 days. Total polyphenol, 2,2-diphenyl-l-picrylhydrazyl (DPPH) radical scavenging activity, acid value, peroxide value, volatile basic nitrogen (VBN), and total bacterial cell contents were analyzed. Total polyphenol content and DPPH radical scavenging activity increased according to the amount of purple sweet potato, whereas acid value, peroxide value, and VBN decreased. Addition of 0.2% purple sweet potato pigment increased lipid oxidative stability and protein deterioration inhibitory effect compared to F0, but not to the levels of 0.15% sodium nitrite. However, F2 showed the lowest pH during storage due to the pH (2.52) of the pigment. Microorganism analysis revealed that total bacterial counts of sausage added with 0.2% purple sweet potato pigment were significantly lower (P<0.05) than that of sodium nitrite-supplemented sausage. As a result, purple sweet potato powder and pigment demonstrate antioxidative activity and lipid oxidative stability in sausages, making them suitable ingredients for manufacturing sausages.