• Food Science of Animal Resources
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• v.36 no.2
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• pp.215-222
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• 2016

The combined effects of irradiation and aging temperature on the microbial and chemical quality of beef loin were investigated. The samples were vacuum-packaged, irradiated at 0 or 2 kGy using electron-beam (EB), and stored for 10 d at different aging temperatures (2, 14, or 25℃). The microbial growth, shear values, meat color, and nucleotide-related flavor compounds of the samples were analyzed. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and Escherhia coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose. Irradiation reduced the total aerobic bacteria (TAB) over the storage, but higher aging temperature increased the TBA. Thus TAB increased sharply in non-irradiated and high temperature-aged (14, 25℃) beef samples after 5 d. With increasing aging temperature and aging time, shear force values decreased. Lipid oxidation could be reduced by short aging time at low aging temperature. The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the aging period. As aging period and temperature increased, IMP decreased and hypoxanthine increased. Considering microbial and physicochemical properties, irradiation can be used for raw beef to be aged at relatively high temperature to shorten aging time and cost.

• Applied Chemistry for Engineering
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• v.33 no.3
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• pp.235-241
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• 2022

According to the World Water Development Report 2015 released by the United Nations, drinking water is expected to decrease by 40% by 2030. This does not mean that the amount of water decreases, but rather that the water source is contaminated due to environmental pollution. Because microbes are deeply related to water quality, the analysis of microbe is very important for water quality management. While the most common method currently used for microbial analysis is microscopic examination of the shape and feature after cell culture, as the gene analysis technology advances, quantitative polymerase chain reaction (qPCR) can be applied to the microscopic microbiological analysis, and the application method has been studied. Among them, a reverse transcription (RT) step enables the analysis of RNA by RT-PCR. Integrated cell culture (ICC)-qPCR shortens the test time by using it with microbial culture analysis, and viability qPCR can reduce the false positive errors of samples collected from natural water source. Multiplex qPCR for improved throughput, and microfluidic qPCR for analysis with limited amount of sample has been developed In this paper, we introduce the case, principle and development direction of the qPCR method applied to the analysis of microorganisms.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.588-595
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• 2003

The optimum level of fresh granulated low-calcium (0.2%) skim milk co-precipitate, as fat substitute in low-fat ground pork patties was determined on the basis of physico-chemical, cooking and sensory properties. Low-fat ground pork patties (<10% total fat), formulated with 15 per cent water, 4 per cent added fat, 1.5 per cent salt and 4-10 per cent milk co-precipitate, were evaluated for proximate composition, cooking characteristics and compared with control patties with 15 % added fat. The moisture and protein content of raw and cooked low-fat patties were significantly (p<0.05) higher than control. The incorporation of milk co-precipitate in low-fat patties improved cooking yield, fat and moisture retention and reduced shrinkage. The sensory properties of low-fat patties were comparable with control patties. The overall acceptability of low-fat patties formulated with 7% milk co-precipitate was significantly (p<0.05) higher than patties with 10% level and non-significantly (p<0.05) higher than low-fat patties containing 4% milk co-precipitate and control. Instrumental Texture Profiles of developed low-fat patties and control patties were comparable with slight increases in hardness and gumminess of the low-fat product. The developed low-fat ground pork patties (7% milk co-precipitate) had lower TBA values, better microbiological and sensory refrigerated storage stability than high-fat control patties packaged in air permeable films for 21 days.

• Korean journal of food and cookery science
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• v.17 no.5
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• pp.510-516
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• 2001

Hydroponic cultivation is a technology of raising crops without use of soil. Generally farmers use the method of DFT(deep flow technology)to grow leafy or fruity vegetables; however, systematic and scientific researches are insufficient on this matter. This study investigated the possibility of cultivating Chinese cabbage steadily year long by using the method of DFT. Chinese cabbage was cultivated hydroponically with and without Ge addition, used to prepare kimchi, and the chemical and microbiological characteristics of kimchi were compared. The basic hydroponic cultivation condition was as follows: 30 days after seeding, the raised seeds were moved to a hydroponic bed and given underground water for 3 days so the roots grow normally Standard nutrient solution was provided and the early electric conductivity concentration was maintained between 1.5∼2.5 thickness. The temperature of the solution was maintained between 10 ∼25$^{\circ}C$ to allow the growth of Chinese cabbage. When soil-cultivated, organically cultivated and hydroponically cultivated Chinese cabbages were compared, hydroponically cultivated cabbages were smaller in size and showed less ability to build up and fold leaves into a head, but showed better quality than organically cultivated cabbages. The contents of protein and fat showed no significant differences. The contents of water. Ca, P, Fe, Vitamin A and Niacin were higher in control and Ge-added cabbages compared with soil-grown cabbage. There was no difference between soil-cultivated Chinese cabbage kimchi and hydroponically cultivated Chinese cabbage kimchi.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.196-213
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• 2021

The objective of this study was to determine the effects of yeast cultures (Candida zeylanoides and Debaryomyces hansenii) isolated from traditionally dry fermented Turkish sucuks, on some physicochemical and microbiological properties of the product. Eight different batches of the sucuks were produced by the inoculation of yeast and lactic acid bacteria (LAB) cultures (Lactobacillus curvatus, Lactobacillus plantarum and Lactobacillus sakei) in different combinations. The sucuks were ripened for 12 days and analyzed at 1st, 6th, and 12th days of ripening. Percent moisture content, pH, water activity (aw) and residual nitrite values of the sucuk inoculated with the yeast cultures were higher at the end of the ripening. The use of yeast cultures decreased hardness, gumminess, and chewiness values of the sucuk while increased adhesiveness values. Major volatile groups were aldehydes, terpenes, and sulphur compounds in the sucuk samples. The most noticeable results were for sensory properties of the sucuk that were positively improved by the yeast cultures.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.2
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• pp.122-128
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• 2024

We investigated the quality of 10 commercial eorigul-jeot, salt-fermented oysters with seasoning, by measuring their chemical composition and bacterial concentrations. The Eorigul-jeot had 5.07-6.06 pH (mean, 5.63), of 1.92-4.74% salinity (mean, 3.36%), 7.01-14.70 mg/100 g volatile basic nitrogen (mean, 11.91 mg/100 g), 139.22-267.11 mg/100 g amino acid nitrogen (mean, 212.69 mg/100 g), and 1.02-1.65 g/100 g total acidity (mean, 1.24 g/100 g). The total viable and lactic acid bacterial counts were 5.7×10⁴-8.7×10⁵ and 2.7×10³-2.0×10⁵ CFU/g, respectively, and fecal coliform was detected in only one Eorigul-jeot sample. Bacillus cereus and Clostridium perfringens were detected in two samples, and all Eorigul-jeot samples were negative for Staphylococcus aureus and Vibrio parahaemolyticus. These results strongly suggest the need to monitor food-poisoning bacteria in commercial Eorigul-jeot to ensure consumer health.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.198-203
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• 2012

To improve hygienic quality of egg, the ozone treatment was applied. Eggs were inoculated with Salmonella Typhimurium, and the inoculated eggs were treated by ozone (38.8 ppm) for 10-30 min. Furthermore, microbiological and chemical quality changes of eggs were investigated during storage. Initial number of S. Typhimurium of egg shell was 6.18 log CFU/g and the number was increased during storage (p<0.05). However, those of ozonated samples for 10-30 min were 4.22-5.25 log CFU/g, which was lower than that of the control. Especially, ozone treatment for 30 min achieved about 2 decimal reductions and the numbers were maintained during storage. Other physical and chemical characteristics of eggs by ozone treatment, including Haugh unit, yolk color, pHs of egg white and yolk, foaming ability, foam stability and lipid oxidation development were not different when compared with that of the control. Therefore, ozone treatment is one of the available methods to improve hygienic quality of eggs.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.527-531
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• 1991

Frozen mandu, which is one of the main frozen prepared foods, purchased from a local manufacturer, were stored at five constant temperatures ($0,\;-5,\;-10,\;-20\;and\;-30^{\circ}C$) for six months. Effects of the storage temperature and the storage period on the changes in pH, acid value, peroxide value, volatile basic nitrogen, color, sensory score and microbial counts of frozen mandu were studied. The changes in microbiological and physicochemical characteristics were significantly increased in comparison with the initial value after 1 month at $0^{\circ}C$, after 3 months at $-5^{\circ}C$ and after 5 months at $-10^{\circ}C$, but nearly constant in spite of storage periods when the temperature dropped below $-10^{\circ}C$Out of five chemical components, AV and POV were the most reliable components in the quality judgement of frozen mandu and its upper limiting content were 2.56 and 19.35 meq/kg each. Regression equation for shelf life prediction of frozen mandu with sensory scores and POV was determined.

• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.328-333
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• 2000

This study was carried out to changes in chemical and microbiological properties of spring waters in Tongyeoung area. In this paper, ninety spring water samples were collected from 9 station for 11 month to evaluated chemical and bacteriological water quality. Range and mean values of constituents of the samples are as followed; water temperature 5.2~25.8$^{\circ}C$, 16.3$^{\circ}C$, pH 6.0~7.2, 6.7, total residue 33.6~210 mg/1, 90.6 mg/1, turbidity 0.35~5.48, 1.45NTU, KMnO4 consumed 0.51~4.21 mg/1, 1.39 mg/1, chloride ion 6.23~42.5, 16.7 mg/l, phosphate-phosphorus ND-0.04, 0.02 mg/1, nitrite-nitrogen ND~0.02, 0.01 mg/1, nitrate-nitrogen ND~3.56, 1.42 mg/1, ammonia-nitrogen ND~0.20, 0.14 mg/1, dissolved total nitrogen ND~3.78, 1.57 mg/1, iron 0.04~0.28, 0.13ppm, zinc 0.03~0.66, 0.20ppm, mangan ND~0.01, allumium 0.14~0.58, 0.39ppm, copper ND~0.01, 0.01, lead ND~0.01, 0.01ppm, Arsenic ND~0.01, 0.01ppm, mercury ND~0.02, chrome not detected, cadmium not detetced respectively. The viable cell counts of the spring waters ranged 5.0~760/m1(means 130/m1). Range and mean value of total coliform and focal coliform MPN's of the spring waters were 0~2,400MPN/100 ml, 73MPN/100 ml and 0~540MPN/100 ml, 21MPN/100 ml. Spring water quality was usually poor with viable cell counts exceeding 130 CFU/liter and the coliform counts in spring waters of 73 MPN/liter. Composition of coliform by IMViC reaction was 33.3% E. coli, 15.6% Citrobacter freundii, 35.6% Klebsiella aerogenes and others.

• Food Science of Animal Resources
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• v.40 no.3
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• pp.362-376
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• 2020

Rabbit meat bekasam is a traditional fermentation product from Indonesia. This study aimed to determine the chemical and microbiological characteristics of rabbit meat bekasam during the fermentation process in order to isolate, characterize (in vitro and in vivo), and identify lactic acid bacteria (LAB) as the probiotic candidate. The chemical contents of bekasam on 7-day fermentation were investigated in explorative and experimental methods in a completely randomized design. A proximate analysis reported a decrease in the moisture content, fat and carbohydrate content, and an increase in protein content. Also, lactic acid content was increased from 0.48% to 1.12%, and pH was decreased from 5.3 to 4.3. Other properties indicated different values, such as bacteria (2.75×10⁶ to 4.45×10⁷ CFU/g), total LAB (3.82×10⁶ to 4.67×10⁸ CFU/g), total yeast (9.89×10⁶ to 3.82×10⁸ CFU/g) and total mould (4.34×10¹ to 4.86×10³ CFU/g). The experiment produced nine LAB isolates, including two probiotics subjected to further 16S rRNA gene analysis, which indicated that Lactobacillus buchneri was the potential probiotic isolate. After being tested on BALB/c mice, L. buchneri could improve the immune system by inhibiting the growth of Coliform and Salmonella.