• Journal of Radiation Industry
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• v.10 no.4
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• pp.205-210
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• 2016

This study was conducted to evaluate the combined effect of gamma irradiation and different conditions (vacuum packaging, antioxidant and freezing) on the microbiological and sensory characteristics of freeze dried Manila clam porridge (MCP) for immuno-compromised patient food. MCP can be sterilized at 1 kGy to 10 kGy. The initial counts of total aerobic bacteria and yeast molds in the non-irradiated MCP were $2.4{\pm}0.5$ and $1.2{\pm}0.3{\log}\;CFU\;g^{-1}$, respectively, but gamma irradiation significantly decreased the total aerobic bacteria to below the detection limit ($1{\log}\;CFU\;g^{-1}$) (5 kGy). Moreover, gamma irradiation effectively eliminated yeasts/molds at dose below than 1 kGy. However, gamma irradiation accelerated the increase of lipid oxidation and therefore, decreased the sensory characteristics of MCP as irradiation dose increased. To improve the sensory qualities of gamma irradiated MCP, combination treatment (vacuum packaging, 0.1% vitamin C) were applied. There was no significant difference in the overall acceptance scores between the combined-treatment sample (5.6 points) and the non-irradiated samples (6.0). The results indicate that combination treatment (vacuum packaging, 0.1% vitamin C) may help to maintain the quality of MCP. Therefore, it considered that irradiation of MCP with combined treatment and this is an effective method for the consumption as a special purpose food such as for space travel or immuno-compromised patients.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.20-29
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• 2002

Standard recipes of various fish dishes for cook/chill system were developed to provide foodservice managers in kindergarten with more effective management system. Three kinds of fish dishes, Broiled Mackerel, Flounder Stew and Squid Bulgogi were selected as menu items in this study, and the standard recipes for these fish dishes were developed through the sensory evaluation, and microbiological analyses were performed to assure the quality of fish dishes. The microbial counts of the fish dishes which were chilled at 0∼3$^{\circ}C$ and stored for 10 days in refrigerator were as follows : Aerobic bacteria were not detected in Broiled Mackerel; however, those in Flounder Stew were 2.92${\pm}$0.01∼3.84 ${\pm}$0.06 Log CFU/g and those in Squid Bulgogi were 3.16${\pm}$0.01∼4.80${\pm}$0.02 Log CFU/g. Coliform bacteria were not detected in any fish dishes. All the sensory characteristics showed no significant differences between the first and third day of storage, except the feeling after swallowing of Flounder Stew. Overall acceptability scores of chilled stored foods in the first and third day were 6.87${\pm}$0.99 and 6.40${\pm}$1.40 in Broiled Mackerel, 6.87${\pm}$0.35 and 6.73${\pm}$1.10 in Flounder Stew, 6.13${\pm}$0.99 and 6.07 ${\pm}$0.80 in Squid Bulgogi, respectively.

• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.183-193
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• 2014

This study is conducted to evaluate the effects of gamma irradiation (0.4, 0.6, 0.8, 1 and 1.5 kGy) on the microbiological, physicochemical and sensory qualities of imported oranges during storage at $20^{\circ}C$ for 15 days. Total aerobic bacteria and yeast/mold counts in non-irradiated oranges increase significantly with increasing storage time. Irradiation has effects on the reduction of microorganism of dose-dependent oranges. The vitamin C contents decrease significantly according to dose-dependent manners and storage times after the gamma irradiation. Sensory evaluation decreases according to dose-ependent manners and storage times, excluding the color. The results suggest that gamma irradiation is effective for ensuring the microbiological safety, but the irradiated oranges more than 1 kGy are not good for physicochemical and sensory qualities. Therefore, irradiated samples of 0.4~0.6 kGy are considered as the optimum-dose for maintaining quality.

• Food Science and Preservation
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• v.14 no.4
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• pp.408-413
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• 2007

This study evaluated the sensory quality characteristics of gamma-irradiated Sujeonggwa a Korean traditional cinnamon beverage during storage, and the mutagenicity of the beverage. The minimum irradiation dose required to ensure the microbiological safety of powdered Sujeonggwa was 4.5 kGy. Sensory characteristics, and the Hunter's color value, of Sujeonggwa, deteriorated with increased irradiation doses, but no significant changes in sensory qualities were found during storage. The Ames test yielded no evidence that gamma irradiation induced mutagenicity in Sujeonggwa powder.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.506-514
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• 2018

The aim of this study was to evaluate the effects of marinade under different conditions (temperature and vacuum) on pork ham cooked by the sous-vide method ($61^{\circ}C$ and 98.81% vacuum for 45 min). Control group was non-marinade pork ham. The samples were marinated under 1 of 4 conditions: $4^{\circ}C$, 98.81% vacuum (treatment group $T_1$); $4^{\circ}C$, atmospheric pressure ($T_2$); $20^{\circ}C$, 98.81% vacuum ($T_3$); and $20^{\circ}C$, atmospheric pressure ($T_4$). The pH value was higher in the control (6.02) than in the treatment groups (4.30-4.42, p<0.001). Shear force was the lowest in the control: 18.14 N. Lightness and redness values were higher in the control (p<0.001). The chroma value significantly decreased from 12.74 to 7.55 with marinade (p<0.001). Total viable and coliform counts of raw meat were 84.6 and 3.67 Log CFU/g, respectively. After the marinade, the total viable count decreased to 3.00-14.67 Log CFU/g (p<0.001). Coliforms were not detected. After sous-vide cooking, no viable microorganisms were detected in any group. Treatment groups generally showed high scores on consumer preference. The marinade and sous-vide cooking had a positive effect on sensory characteristics. They provided safe conditions for sanitary evaluation. As a result, it appears that marinade at refrigeration temperature is better than that at room temperature.

• Preventive Nutrition and Food Science
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• v.8 no.2
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• pp.191-195
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• 2003

We investigated the effects of gamma irradiation on the microbiological, chemical and sensory qualities of bulgogi, a traditional Korean meat product. Gamma irradiation reduced the number of coliform bacteria and bacterial colonies counted in Salmonella-Shigella selective agar to a non-detectable level. Thermophillic microorganisms (mainly Bacillus spp.) in bolgogi refrigerated for 20 days were also significantly reduced by 3 log cycles by 2.5 to 7.5 kGy of irradiation, compared to the control. Electron donating ability and shear force of ready-to-cook bulgogi was not significantly affected by gamma irradiation. Irradiation increased the 2-thiobarbituric acid reactive substances (TBARS) value. The irradiated, raw, ready-to-cook bulgogi had significantly higher scores in color and appearance than those of non-irradiated controls from sensory evaluation. The overall acceptance of cooked bulgogi had higher scores in non-irradiated or 2.5 kGy-irradiated bulgogi than the 5.0- or 7.5-kGy irradiated counterparts. In conclusion, irradiation at 2.5 kGy is recommended as a method to improve shelf-life, safety, and to achieve acceptable quality of ready-to-cook bulgogi without any adverse changes in the sensory characteristics.

• Korean journal of food and cookery science
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• v.23 no.2 s.98
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• pp.187-194
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• 2007

The quality characteristics of brand and non-brand Korean beefs, found in retail circulation, were studied via physicochemical and microbiological analysis and sensory tests. The average price of 100 g of brand Korean beef sirloin was 7.6 USD (1USD=950won), while the price of non-brand Korean beef was 3.1 USD. The fat content of the brand beef seemed to be higher, yet the difference was not significant. In both the brand and non-brand beefs, pH levels were approximately 5.27 We found that lightness (Hunter L value) tended to be higher in the brand beef, but again, this difference was not significant. For the cooked beef texture, the brand beef seemed to have lower gumminess, and had significantly less fracturability, than the non-brand beef. Significant differences could not be found with regards to microbiological stability between the two types of beef. In the raw beef sensory test, significant differences were identified for meat color, fat color, fat in muscle, flavor, and general preference. Also, the after cooking sensory test showed that brand beef had better characteristics for color, flavor, juiciness, softness, taste, chewiness, and preference.

• Food Science and Preservation
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• v.15 no.5
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• pp.648-655
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• 2008

A gamma irradiation process was applied to prolong the shelf-life of grapes and changes in microbiological, physicochemical, nutritional, and sensory characteristics were investigated during 6 weeks of post-irradiation storage at $4^{\circ}C$ and $25^{\circ}C$. Physiochemical characteristics of grapes such as total sugar content, pH, titratable acidity, and anthocyanine content, were stable after 1 kGy of irradiation, a dose recommended by CODEX for fruits and vegetables. The viable cell counts of contaminating microorganisms were reduced 1-2 logs by this radiation dose. After 6 weeks of storage at $4^{\circ}C$ the microbiological quality of irradiated grapes was stable, but all non-irradiated grapes had deteriorated. Whether or not grapes were irradiated, weight loss rapidly increased after 2 weeks of storage at $25^{\circ}C$, whereas weight loss was delayed by storage at $4^{\circ}C$. Immediately after gamma irradiation, the sensory evaluation results did not differ between samples, and the sensory quality of the irradiated grapes remained acceptable for over 6 weeks of storage at $4^{\circ}C$. The results suggest that 1 kGy of gamma irradiation does not detrimentally affect the nutritional or physical characteristics of grapes, especially when cold storage follows radiation treatment. In conclusion, a combination of gamma irradiation and cold storage prolonged the shelf-life of grapes by 6 weeks.

• Korean journal of food and cookery science
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• v.16 no.5
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• pp.453-459
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• 2000

Quality characteristics of Yaksik prepared with glutinuous rice soaked for different time lengths were investigated. Moisture contents increased with the increment of soaking time. In Hunter's color value, the lightness decreased and redness and yellowness increased by the increment of soaking time. Samples prepared with a commercial formula showed increased red and yellow colors due to the addition of caramel sauce. The firmness decreased with the increment of soaking time during storage. However, the samples prepared with 2 hr-soaking were retrograded rapidly. In peroxide value, there were no differences among samples. In microbiological evaluation, samples prepared with a commercial formula had prolonged shelf lives probably due to the preservatives contained. Samples prepared with 6 hr-soaking showed the highest score in sensory evaluation.

• Korean journal of food and cookery science
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• v.31 no.1
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• pp.9-17
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• 2015

Shindari is a traditional fermented drink of Jeju in Korea, which is made with boiled barley and nuruk for short fermentation periods. This study determined chemical, microbiological, and sensory characteristics of the modified Shindari with 15% carrots as an additive (carrot Shindari), and this study compared it with a traditional Shindari as a control. After fermentation at $30^{\circ}C$ for a day, the pHs of the carrot Shindari and traditional Shindari largely decreased, and the total acidities increased in both of the Shindari. The significantly higher scores of Hunter's color values were observed more in carrot Shindari than in traditional Shindari. Also, carrot Shindari (0.4954 g/100 g) had a significantly higher content of vitamin C than traditional Shindari (0.0030 g/100 g). The most abundant free sugar and organic acid were glucose and lactic acid, respectively, in both of the Shindari. The total numbers of bacteria, fungi and lactic-acid bacteria in both samples increased by log 3 CFU/mL after fermentation. Based on 16S ribosomal RNA gene analysis, the dominant lactic-acid bacteria was Pediococcus acidilactici in both samples. The DPPH (1.1-diphenyl-2-picrylhydrazyl) radical scavenging activity of carrot Shindari (60.13%) was higher than that of traditional Shindari (23.70%). In sensory evaluations (taste, flavor, color, and overall acceptance), the carrot Shindari had higher scores in all these values. In this study, the modified Shindari with carrot presenting high sensory characteristic as well as chemical and microbiologic characteristics provide an opportunity to improve the application of a traditional fermented drink of Jeju, Shindari.