• Journal of Dairy Science and Biotechnology
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• v.34 no.3
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• pp.199-202
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• 2016

Processing methods of heat treatment in milk has been developed to increase safety for the consumer by destroying pathogens that may be found in milk. Commercial pasteurization of milk in the market started in the late 1800s in Europe and in the early 1900s in the United States. In 1962, it became a requirement in Korea that all milk for sale should be treated by heat. Nowadays, heat treatment (pasteurization or sterilization) became mandatory for all milk products sold in all over the world. However, since 1987, there was a big debate about the heat-treatment of milk. Korea Society of Dairy Science and Technology (KSDST) complied the 10 scientific articles of milk heat-treatment into the book which titled "Effects of the heat-treatment on the nutritional quality of milk". Almost several hundred copies had been distributed at the symposium KSDST in 1989. Currently, no one was able to find these articles in anywhere including library etc. Thus, author decided to re-write that books in serials because these articles should be pass on their knowledge of milk science to the next generation of milk research.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.635-641
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• 2003

A non-thermal pasteurization technology, high Pulsed Electric Field (PEF) has been thought to be a new alternative processing technology instead of heating. The objective of this study was to examine and compare the effect of PEF and High Temperature Short Time (HTST) treatments on the physicochemical, microbiological and sensory characteristics of citrus juices. Total sugar and titratable acidity values of fresh citrus juice and two treatments were not significantly different each other at p<0.05. The concentration of vitamin C in fresh citrus juice $(31.2{\pm}0.59\;mg%)$ was not significantly different with the value of PEF treatment $(29.4{\pm}0.75\;mg%)$ but was significantly higher than the value of HTST treatment $(27.4{\pm}0.75\;mg%)$. The color values (L, a, and b) in PEF treatment were significantly lower than the fresh citrus juice, but were higher than the values of HTST treatment. Both total bacterial cell counts $(6.65\;{\pm}\;0.08\;log_{10}(cfu/mL))$ and yeast counts $(7.79{\pm}0.07\;log_{10}(cfu/mL))$ in fresh citrus juice were significantly reduced by PEF $(1.39{\pm}0.14,\;2.42{\pm}0.1\;log_{10}(cfu/mL))$ as well as HTST treatment (0, 0). PE activity of fresh citrus juice $(1.3{\pm}0.12\;units/mL)$ was significantly reduced by PEF treatment $(0.11{\pm}0.01\;units/mL)$ and was totally inactivated by HTST treatment. Sensory evaluation scores in flavor, taste and overall acceptability between the fresh and PEF treated citrus juices $(7.2{\sim}7.5)$ were not significantly different but the values of HTST treatment $(5.1{\sim}5.8)$ were lower than others. Consequently, PEF treatment is thought to be a good alternative pasteurization method for fresh citrus juice to HTST treatment due to its strong pasteurization effect, reduced destruction of nutrients and good sensory characteristics.

• Korean Journal of Food Science and Technology
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• v.7 no.4
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• pp.200-207
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• 1975

This experiment was carried out to investigate the chemical composition and microflora of soy sauce during storage under the different temperature. The results obtained are as follows. (1) Total nitrogen, color density, specific gravity and sodium chloride concentration of soy sauce showed a increasing tendency in the progress of storage period. Open-storage state at $30^{\circ}C\;and\;15^{\circ}C$ were responsible to the increase of components as compare with close-storage state at $5^{\circ}C$. (2) pH and buffer action were not almost changed during the storage. (3) Alcohol and sugar contents of soy sauce showed a decreasing tendency in the process of storage period, especially in the case of open state alcohol being almost disappeared within 11 months in all groups. (4) The number of common bacteria in one ml of soy sauce were counted as $96{\times}10^4$ before pasteurization and $10^3$ after pasteurization. The osmophilic bacteria was counted as $38{\times}10^4$, $10^2$ after pasteurization. (5) The spore number of mold in one ml of soy sauce were counted $32{\times}10^7$ before pasteurization, 58 after pasteurization and 10 to $10^2$ in the progress of storage period. (6) The bacteria number of soy sauce were somewhat decreased with the passing, of the time. The group of high temperature and open state were more notable than low temperature and close state.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1857-1863
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• 2013

Bulgogi sauces containing electron beam-irradiated garlic powder (1%, 3%, and 5%) were used to compare their irradiation status before and after pasteurization ($85^{\circ}C$, 30 min), using a thermoluminescence (TL) analysis by two different laboratories. The sauces with non-irradiated ingredient only provided a background TL glow curve with a maximum peak after $300^{\circ}C$. However, the presence of irradiated ingredient (1 and 10 kGy) was evident through the typical TL glow curves in a temperature range of 150 to $250^{\circ}C$. The concentration of irradiated ingredients showed a greater impact on identification characteristics than their radiation doses. TL ratios ($TL_1/TL_2$) were not able to confirm the results showing evidence of irradiation through the TL glow curve shapes. Pasteurization showed a negligible effect on the key identification parameters and did not change the shape or temperature range of radiation-specific TL glow peak, but reduced TL glow curve intensity. TL glow curve shape with the maximum peak in a temperature range of $150{\sim}250^{\circ}C$ was the most useful characteristic providing information required for confirming the irradiation status.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.147-152
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• 1999

HPLC was used for determining polyphenols which are known as the functional compounds in the unripe apples Fuji and Aori. The changes in their contents caused by heat treatments were monitored. The carbohydrate contents in Fuji and Aori were 14.1% and 13.5% respectively. Both apple juices showed pH 3.2 and $8.0\;brix^{\circ}$, which were relatively low levels. The major polyphenols were composed of (+)-catechin, chlorogenic acid, (-)-epicatechin, and tannic acid. Total polyphenol contents in Fuji and Aori were 0.11, 0.12% by Folin-Denis method. HPLC analysis of polyphenols showed that four major components were contained by 0.06% in Fuji and 0.07% in Aori. Chlorogenic acid was three times higher in Fuji than in Aori. After water blanching, the area percent of polyphenols resulted in an increase by 3.54% in Fuji but a decrease by 2.93% in Aori. Pasteurization of juices led to decrease by 1.39% and 3.31% respectively. Blanching and pasteurization of unripe apple juices induced negligible changes in polyphenol contents during storage. During concentration, polyphenol contents increased in proportion to the concentration of unripe apple juices.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.301-308
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• 1987

The results of experiment to find out the optimum pasteurization condition by heating from $50^{\circ}C$ to $70^{\circ}C$ at intervals of $5^{\circ}C$ and to review chemical composition, microbiological aspects and keeping quality were summarized as follows: 1. The milk sample pasteurized at $50-70^{\circ}C$ showed the decreased pH value from 6.55 to 6.42 while the contents of protein, fat, lactose and ash did not have significant changes. 2. Non-casein nitrogen and filterable nitrogen decreased while casein nitrogen and non protein nitrogen increased as the heat treatment increased. 3. The content of calcium and vitamin C decreased and artificial digestibility for the pasteruized milk increased from 14.07% to 20.00% by the heat treatment. 4. Milk pasteurized at $65^{\circ}C$ had viable bacteria counts $1.3{\times}10^4/m{\ell}$, coliforms negative, psychrotrophic bacteria $9.5{\times}10^2/m{\ell}$ and 99.0% pasteurization effect. 5. Milk pasteurized at $65^{\circ}C$ did not show significant changes in chemical composition and microbiological aspects at $4^{\circ}C$ in refrigerator.

• Journal of Food Hygiene and Safety
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• v.15 no.1
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• pp.18-24
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• 2000

In this study, ohmic heating was applied for pasteurization of red pepper pow-der, and investigated its pasteurization effect. After pasteurization, seasoned squid-jeotkal was manufactured by using red pepper powder, and its quality changes were investigated. On com-paring sensory evaluation in squid-jeotkal by pasteurized and conventional red pepper powder during storage at 5, 16 and $25^{\circ}C$, quality changes in squid-jeotkal by the pasteurized red pepper powder. But quality change difference between two products were decrease with increasing stor-age temperature. Viable cell counts in two products stored at 5$^{\circ}C$ were increased slowly until 60 days. Viable cell counts in squid-jeotkal by conventional red pepper powder were increased up to ca. 10$^{8}$ CFU/g at 15, 25 $^{\circ}C$ after 30, 15 days, respectively, but that by pasteurized were ca. 10$^{8}$ CFU/g at $25^{\circ}C$ after 30 days. Changes in pH, VBN and NH$_2$-N in two products were shown difference significantly, but were decreased by increasing storage temperature. In squid-jeotkal by conventional red pepper powder, the main free amino acids were glutamic acid, leucine, glycine, aspartic acid and alanine, and these amino acids held 47.95% of the total free amino acid. But in squid-jeotkal by pasteurized red pepper powder, glutamic acid, glycine, aspartic acid, leucine and Iysine, and these amino acids held 57.58% of the total free amino acids.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1577-1582
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• 1999

Carrot juice inoculated with $2\;{\times}\;10^8\;cfu/mL$ of Escherichia coli was treated with pulsed electric fields(PEF) for the purpose of a development of new cold pasteurization processes. Inactivation of E. coli in carrot juice increased with increase in intensity of the electric field strength and treatment time. The cells were suspended at concentration of ca. $2\;{\times}\;10^8$ cells per ml. A reduction of 4D was obtained at 40 kv/cm and 256 exponential decay pulses at room temperature. Critical electric field strength(Ec) and treatment time(tc) needed for inactivation of E. coli were 11.74 kV/cm and $3.6\;{\mu}s$ at room temperature, respectively. The combination of PEF and thermal treatment inactivated E. coli more effectively. The reductions of up to 5.5D were observed when the carrot juice was treated with PEF of 22.5 kV/cm and $205\;{\mu}s$ at $50^{\circ}C$. PFF treatment did not effect in color, pH, $^{\circ}Brix$, titratable acidity and ${\alpha}-,\;{\beta}-carotene$ contents of carrot juice.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.204-206
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• 2003

Electron beam generator of cold cathode type has been developed for industrial application, for example, waste water cleaning, flue gas cleaning, and pasteurization etc. The operational principle is based on the emission of secondary electrons from cold cathode when ions in the plasma hit the cathode, which are accelerated toward exit window by the gradient of an electric potential. The characteristics of secondary electron emission are studied by comparing total cathode current with ion current.

• Proceedings of the KIEE Conference
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• 2005.11a
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• pp.207-209
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• 2005

Ultra wide band electromagnetic energy can be transmitted to a far field by emitting the nanoseconds high voltage pulse electromagnetic energy via an antenna. This UWB EM energy is expected to be used in post-packing pasteurization of food, detection of buried objects or underground water veins and caves and the treatment of waste water or polluted gas. The nanoseconds pulse forming for UWB generation using high voltage blumlein line and an ultrafast switch is mentioned.