• Korean Journal of Veterinary Research
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• v.4 no.1
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• pp.19-22
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• 1964

The alcohol precipitation test(APT) is widely used in the inspection of cow milk, whereas the APT in goat milk inspection is not specifically known. The APT is used to determine the precipitating ability of milk by heat used in sterilization and evaporating process at the milk plant. The APT may also be used to detect abnormal milks such as acid milk, colostrum, and any milk in which the salt balance is disturbed so that it may be more subject to precipitation than normal milk. In the experiments the applicability of the APT of goat milk was studied. The results obtained by using 87 sample of goat milk are as follows: 1. As all the fresh samples(100%) were APT positive by using 70% ethanol which is used in the practice of cow milk and 3 out of 87 samples(3.7%) were positive by using 45% ethanol, it is suggested that 45% ethanol may be applied in the APT of goat milk. 2. The distribution of natural acidity (apparent acidity) was between 0.12%-0.30% and the amount of natural acidity did not significantly affect the precipitating ability of goat milk by APT. 3. The freshness of goat milk cannot be detected sharply by APT even though 45% ethanol is applied.

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.817-828
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• 2023

Deteriorating soil physical properties and increasing soil pathogens due to the continuous cultivation of field crops are the leading causes of productivity deterioration. Crop rotation, soil heat treatment, and chemical control are used as pest control methods; however, each has limitations in wide application to domestic agriculture. In particular, chemical control requires improvement due to direct exposure to sterilizing solution, odor, and high-intensity work. To improve the overall domestic agricultural environment, the problems of time and cost, such as field maintenance and cultivation scale, must be addressed; therefore, mechanization technology for chemical control must be secured to derive improvement effects in a short period. Most related studies are focused on the control effect of the DMDS (dimethyl disulfide) sterilizer, and research on the performance of the sterilization spray device has been conducted after its introduction in Korea, but research on the corrosion suitability of the material is lacking. This study conducted a corrosion test to secure the corrosion resistance of a soil sterilizer injection pump, and a mechanical failure mode by corrosion by the material was established. The corrosion test comprised operation and neglect tests in which the sterilizing solution was circulated in the pump and remained in the pump, respectively. As a result of the corrosion test, damage occurred due to the weakening of the mechanical strength of the graphite material, and corrosion resistance to aluminum, stainless steel, fluororubber, and PPS (polyphenylene sulfide) materials was confirmed.

• Applied Biological Chemistry
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• v.10
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• pp.33-38
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• 1968

In order to determine proper conditions for the manufacture of canned Kimchi, a heat resistant lactic acid bacteria, the most acid producable strain, was isolated and identified as Lactabacillus plantarum. D-value for the isolate was calculated at 3 from a thermal death curve made at $60^{\circ}C$. The effects of acidity of Kimchi and the amount in a can, and the ratios of solid-liquid, were investigated. The most suitable time for sterilization with a type of can was determined as 25.2 minutes at $85^{\circ}C$. However in the period of heat treatment the quality was badly affected and this fact made desirable introducing of a adequate preservative additives into the manufacture of canned Kimchi.

• Journal of Industrial Convergence
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• v.19 no.6
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• pp.67-72
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• 2021

The elevator installed in the building consists of an elevator call button and an input button for selection to the target floor. The elevator button is input only when the elevator user directly presses it. Such passenger input can be infected with an infectious disease due to contamination of the button. A non-contact button is required as a means for solving this problem, which detects the proximity of an object by applying a capacitive method. It implements a function of measuring the body's body temperature by attaching an infrared heat sensor, and provides a sterilization function of a button by attaching a UV-LED. A button was selected, a body temperature was measured through an infrared temperature measurement sensor, and UV-LED was turned on and sterilized when there was no user. The contactless elevator button is expected to be effective in preventing infectious diseases as it can prevent infection of viruses carrying infectious diseases and can detect body temperature to select positive patients of CIVID 19.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1444-1450
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• 2007

To prevent the deterioration of jujube wine quality due to commercial heating process for sterilization, hydrostatic pressure (500 MPa, 5 min) or freezing (frozen at $-20^{\circ}C$ for 3 days, followed by thawing at room temperature for 4 hr) treatment was applied. Their microbial count, physicochemical property and sensory quality were investigated in comparison to heat-treated jujube wine ($63^{\circ}C$, 10 min) and commercial wine. Pressure-treated and commercial jujube wine were completely sterilized and heat-treated wine was decreased to <10 CFU/mL while freezing-treated jujube wine was partially sterilized $(30{\sim}60%)$. Hydrostatic pressure and freezing, and heat treatment had no influence on chemical compositions such as pH, acidity, amino acidity, reducing sugar and ethanol content, but significantly induced the changes of instrumental color. While sensory quality of heat-treated jujube wine was significantly deteriorated, reducing sour and burning taste, that of pressure and freezing-treated jujube wine was maintained fresh without decrease in sour and burning taste.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.620-628
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• 2013

In this study, the condition for preventing abnormal fermentation was set by heating the nuruk extract, such that glycosyl enzymes maintain its activity and unnecessary microbes are removed. The total colony of microbes in the heated nuruk extract was highest in number at $25^{\circ}C$ and began to reduce at 50, $60^{\circ}C$ and sharply reduced over $70^{\circ}C$. Saccharogenic power (SP), glucoamylase and acidic protease activities were highest at $50^{\circ}C$, 10, 20, 30min and ${\alpha}$-amylase activity was lower at $50^{\circ}C$ than at $25^{\circ}C$. In the pHs of the nuruk extract, as the heat temperature became higher and treatment time was longer, the pHs were reduced significantly. The total acidities of heat treatments at 50, $60^{\circ}C$ were lower by 0.2% than at $25^{\circ}C$, where as the 70, $80^{\circ}C$ treatments showed a sharp rise from the early stage of fermentation. Soluble solids showed the same aspects with the glycosyl enzymes cases. In reducing sugar, 25, $50^{\circ}C$ treatments were sharply increased from the first day of fermentation while $60^{\circ}C$ treatments began to rise from second day 70, $80^{\circ}C$ were slightly increased after the fourth day. The normally alcohol fermented treatments were 25, 50 and $60^{\circ}C$ 30min. The $70^{\circ}C$ treatments almost did not alcohol fermentation. In the preference tests, taste and total acceptability were high at 25, $50^{\circ}C$ treatments. These results suggest that makgeolli using heat treated nuruk extract also has good taste as well as did not.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.827-833
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• 1995

Temperature distribution tests for a water cascading horizontal retort utilizing superheated water with overpressure as a heating medium were carried out under three different loading conditions, that is, empty(P-0), half-fully(P-3000) and fully(P-6000) loaded operating conditions. Tank volume and full loading capacity of sterilizer used for this study were about 5,900 liter and 1,140 kg(6000 pouches having 190 g weight each), respectively. Set point condition for sterilization was $122^{\circ}C$, 23 minutes and pressure was maintained in the range of $1.8{\sim}2.0\;kg/cm^2$ during sterilization. For each experiment, time-temperature data and F values were obtained from temperature microprocessor($F_0$ monitor). There were significant variations in the temperature distribution at different positions in the sterilizer. The temperature distribution was also affected by the pouch loading condition significantly. The application of the temperature distribution test to a product (retort pouched curry sauce) was conducted at the fully(P-6000) loading condition. Although heat transfer parameters($f_h\;and\;f_c$), and F values were varied with the position of sterilizer, sensory evaluation showed that the temperature distribution of the sterilizer used in this study didn't affect the quality of retorted curry sauce.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.206-210
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• 1984

Heat penetration pattern of canned oyster mushroom(Pleurotus astreatus) was monitored for processing variables-can size, heating temperature and solid fill fraction, and its effects on sterilization condition was reviewed. The $f_h$ value decreased sharply with decrease of solid fill fraction and then became stable from certain solid fill fraction unique to can size. Heat penetration was a little faster at higher heating temperature with lower $f_h$ value. As viewed from $f_h$ value, convection started at higher solid fill fraction with higher length/diameter ratio, and $f_h$ values decreased to about 1.0 with decrease of solid fill fraction. From standpoint of overall cost, retorting time and energy consumption, solid fill fraction of 3/5 was optimum for all can sizes considered.

• Food Science and Preservation
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• v.21 no.4
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• pp.544-548
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• 2014

This study was conducted to investigate the effects of various heat treatments on the microbial reduction and germination of red radish seeds for the development of effective and economical sterilization methods of improving microbial safety without reducting the germination rate. Hydrothermal treatment was conducted at 60, 65, 70, 75, 80, and $90^{\circ}C$ for 30 and 60 seconds, and dry heat treatment was performed at 70, 80, 90, and $100^{\circ}C$ for 5 minutes. In the seeds that underwent the hydrothermal treatment, time had little effect on the microbial reduction. There was no significant microbial reduction over time. However, there was significant microbial reduction as temperatures increased (p<0.001). The total plate count (TPC) was reduced by more than 3 logs, and Listeria monocytogenes was not detected at temperatures above $70^{\circ}C$. In the seeds that were subjected to the dry heat treatment, the TPC and the population of the L. monocytogenes were significantly reduced as the temperatures increased (p<0.001). After treatment at $100^{\circ}C$ for 5 minutes, the TPC and the L. monocytogenes were reduced by 3 logs. As with the microbial reduction, time had little effect on the germination. There were no significant changes in the germination after the hydrothermal treatment over time; but at the temperatures above $75^{\circ}C$, the germination rate significantly decreased as the temperature increased (p<0.001). When the seeds were soaked after the hydrothermal treatment, their germination was stimulated. The dry heat treatment at temperatures of $80^{\circ}C$ and higher significantly decreased the germination rate as the temperature increased (p<0.001). Dry heat treatment before the germination of the seeds soaked in distilled water for three hours significantly decreased the germination at temperatures greater than $90^{\circ}C$ (p<0.05). This study showed that appropriate heat treatments can increase the microbiological safety and germination of red radish seeds.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.393-395
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• 1992

The ${\alpha}-lactalbumin({\alpha}-la)$ concentration in raw and laboratory-heated milks by HPLC was 1.20 mg/ml (unheated), 1.17 mg/ml ($63^{\circ}C$, 30min), 1.13 mg/ml ($72^{\circ}C$, 15sec) and 0 mg/ml ($100^{\circ}C$, 10min), respectively. Whereas, ${\alpha}-lactalbumin$ concentration ranges of commercial milks were $1.00{\sim}1.02\;mg/ml$ (pasteurized), $0.23{\sim}0.68\;mg/ml$ (UHT-pasteurized) and $0.77{\sim}0.89\;mg/ml$ (UHT-sterilized), respectively. It was supposed that the ${\alpha}-lactalbumin$ content of sterilized milk will be lower than that of UHT milk, but the opposite occurred. This discrepancy would be caused by the different heating system in the milk plants, where indirect UHT-treatment had more heat intensity than direct UHT-processing. The HPLC determination of ${\alpha}-lactalbumin$ may be an indicator to evaluate correctly and rapidly heated milks.