• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1502-1509
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• 2015

The objectives of this study were to evaluate the effect of combined treatments (slightly acidic electrolyzed water (SAEW), ultrasound (US), or mild heat (60℃)) on the growth of Listeria monocytogenes and Salmonella enterica serovar Typhimurium in fresh-cut bell pepper, and the shelf-life and sensory quality (color and texture) were followed during storage at 4℃ and 25℃. An additional 0.65, 1.72, and 2.70 log CFU/g reduction was achieved by heat treatments at 60℃ for 1 min for DW, SAEW, and SAEW+US, respectively. Regardless of the type of pathogen, the combined treatment (SAEW+US+60℃) achieved a significantly (p < 0.05) longer lag time in all treatment groups. This combined treatment also prolonged the shelf-life of bell pepper up to 8 days and 30 h for the storage at 4℃ and 25℃, respectively. There was also no significant difference in the color and hardness of treated (SAEW+US+60℃) bell pepper from that of control during the storage. This new hurdle approach is thus expected to improve the microbial safety of bell peppers during storage and distribution.

• Food Science and Biotechnology
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• 제15권6호
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• pp.838-843
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• 2006

The chemical processes involved in the formation of green pigment in crushed garlic cloves were investigated based on the principle of pink pigmentation in macerated onions. Intact greening and non-greening garlic cloves were either left untreated or heated at $90^{\circ}C$ for 3 min to inactivate enzyme activities. First, a colorless ether soluble compound referred to as color developer reacted with glycine (among all free amino acids) in garlic to form a second compound insoluble in ether. The latter compound then reacted with formaldehyde to yield the green colored pigment. Alliinase activity was necessary for the production of color developer and for the development of green pigment. In greening garlic that had been heat treated, green pigmentation did not proceed due to the heat-inactivation of alliinase, but the addition of alliinase solution into the garlic homogenates restored the pigmentation. However, this phenomenon was not observed in non-greening garlic with or without heat treatment. Finally, the mechanism of green pigment formation in crushed garlicis similar to that of pink pigment formation in macerated onions.

• 한국식품영양학회지
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• 제7권4호
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• pp.345-352
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• 1994

High protein beverage of cow-soy milk was prepared by mixing the soymilk and commercial homogenized cow milk in the various ratios. Effect of heat treatment, pH and addition of calcium and sucrose was studied on the water-soluble nitrogen of cow-soy milk The heat-treated soymilk at 10$0^{\circ}C$ were centrifuged at the range of 830~29,900xg for 30 min and 11,200xg was found to be proper for determination of the degree of protein denaturation by centrifugal method. When soymilk was heated at 70~10$0^{\circ}C$ for 30~240 min, soluble nitrogen (QA SN) in supernatant of protein was decreased to 78.0~56.8% due to protein denaturation. Most of heat denaturation of protein was found to be occurred during Initial heating 10$0^{\circ}C$ for all mixed cow-soy milk. The sedimentation of SN was maximum at pH 4.0 In the range of pH 3~8. Addition of sucrose affected little on oASN while calcium addition reduced %SN significantly to approx. 55% for soymilk(100%). The effect of Ca was less as the ratio of cow milk increased.

• Animal cells and systems
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• 제16권3호
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• pp.215-223
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• 2012

Recently it has been reported that immunization with heat-killed tumor cells (HK vaccine) induces anti-tumor immune responses in mice. To investigate how HKvaccine elicits anti-tumor specific adaptive immunity, we examined the effect of HK vaccination on innate immune cells such as dendritic cells (DCs), which are essential for the generation of adaptive immunity. Upon stimulation with HK vaccine, DCs matured to promote not only the upregulation of co-stimulatory molecules but also secretion of cytokine IL12. Furthermore, HK vaccine-treated DCs migrated more efficiently to draining lymph nodes compared with untreated ones. Taken together, HK vaccine can be useful as an adjuvant to activate DCs for anti-tumor immune responses.

• International Journal of Industrial Entomology and Biomaterials
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• 제39권1호
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• pp.39-44
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• 2019

The effect of heat treatment on the sterilization and fatty acid compositions of silkworm powder was carried out under the guidance of Ministry of Food and Drug Safety. Food borne pathogens or microorganisms including E. coli, Salmonella spp., Listeria monocytogenes, Staphylococus aureus, Clostridium perfringens and aflatoxin, were not detected. The fatty acid composition was hardly changed after the silkworm powder was treated to a high temperature of $121^{\circ}C$. The low temperature sterilization of silkworm powder at $63^{\circ}C$ decreased the concentration of E. coli while high temperature sterilization at $121^{\circ}C$ has found no traces of microorganism.

• 한국축산식품학회지
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• 제43권6호
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• pp.989-1001
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• 2023

Processed foods containing pork fat tissue to improve flavor and gain economic benefit may cause severe issues for Muslims, Jews, and vegetarians. This study aimed to develop an indirect enzyme-linked immunosorbent assay (iELISA) based on a monoclonal antibody specific to thermal stable-soluble protein in pork fat tissue and apply it to detect pork fat tissue in heat-processed (autoclave, steam, roast, and fry) beef meatballs. To develop a sensitive iELISA, the optimal sample pre-cooking time, coating conditions, primary and secondary dilution time, and various buffer systems were tested. The change in the iELISA sensitivity with different 96-well microtiter microplates was confirmed. The detection limit of iELISA performed with an appropriate microplate was 0.015% (w/w) pork fat in raw and heat-treated beef. No cross-reactions to other meats or fats were shown. These results mean that the iELISA can be used as an analytical method to detect trace amounts of pork fat mixed in beef.

• 한국식품위생안전성학회지
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• 제13권4호
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• pp.383-387
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• 1998

본 연구는 포장두부에서 부패 세균을 분리.동정하고, 부패균주의 생육 특성과 내열성을 조사하여 두부 제조공정의 위생관리를 위한 기초 자료로 제시할 목적으로 수행되었다. 포장두부의 부패에 관여하는 세균을 분리하여 Vitek system을 이용하여 동정한 결과, Strain No. T1은 Enterobacter amnigenus일 확률이 92%, Strain No T2는 Flavobacterium indologenes일 확률이 96%이었다. 이들 균주는 $35^{\circ}C$와 pH6.5일 때 가장 생육이 왕성하였다. Enterobacter amnigenus T1의 내열성을 검토한 결과, $60^{\circ}C$에서 2분 처리하였을 경우 초기보다 56.3%, $70^{\circ}C$에서는 37.8%, $80^{\circ}C$에서는 34.0%, $90^{\circ}C$에서 처리했을 때는 22.2%가 잔존하였고, Flavobacterium indologenes T2 경우는 $60^{\circ}C$에서 2분 동안 처리하였을 때 74.8%, $70^{\circ}C$에서는 65.7%, $80^{\circ}C$에서는 37.3%, $90^{\circ}C$에서 처리했을 경우는 9.3%가 잔존하였다.

• 한국식품과학회지
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• 제43권5호
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• pp.577-582
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• 2011

감귤의 유통 중 신선도 유지에 효과적인 것으로 알려진 열수처리를 실제 생산현장에서 적용 가능성을 확인해 보고자 상용 선과장의 선과시설에 열수처리 장치를 장착하여 온실재배 온주감귤을 대상으로 현장처리 실험을 실시한 후 저장 중 품질특성 변화를 관찰하였다. 수확후 감귤을 65$^{\circ}C$의 열수로 10초간 분무한 열수처리구와 무처리 대조구를 5$^{\circ}C$에서 3주, 이후 18$^{\circ}C$에서 1주간 저장하면서 생리특성 및 품질특성 변화를 비교한 결과, 호흡률은 열수처리에 따른 차이가 없었으며 pH, 총산도, 가용성 고형분 함량, 중량감소, 경도, 표피 색과 같은 품질인자 항목에서도 열수처리에 의한 차이를 볼 수 없었다. 그러나 열수처리는 저장 중 꼭지 썩음, 곰팡이 썩음, 표피 흑변 등의 부패과 발생을 현저히 억제시키는 동시에 표면 광택을 포함한 외관품질을 우수하게 유지하였다. 결과적으로 현장실험에서 적용한 열수처리는 상품감귤의 유통 중 신선도 유지용 수확 후 전처리 방법으로서 상당히 효과적임을 확인할 수 있었다.

• 한국축산식품학회지
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• 제28권4호
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• pp.499-504
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• 2008

Microwave,초음파 및 초고압 처리에 의한 PSA의 항원성 변화를 살펴본 결과는 다음과 같다. microwave처리에 의한 변화를 알아본 결과 처리시간이 증가함에 따라 PSA와 항체와의 결합력이 감소하였으며 특히 10분 처리 시에 약 30% 정도로 가장 낮은 결합력을 나타내었다. SDS-PAGE 결과에서는 5, 10분 처리 시에 PSA band가 많이 약화되었으며 immunoblotting에서도 5, 10분 처리한 PSA가 항체와 거의 반응하지 않았다. 하지만 열을 배제하고 microwave 처리한 경우에는 처리구 모두 큰 변화 없이 높은 결합력을 유지하였다. 초음파 처리(5, 10, 30 및 60분)에 의한 PSA의 항원성 변화를 살펴본 결과에서는 초음파 처리구 모두 약 78% 정도의 높은 결합력을 보였으나 immunoblotting에서는 초음파 처리한 PSA가 항체와 거의 반응하지 않았다. PSA에 초고압 처리(200, 300 및 400 MPa)한 후 항원성 변화를 살펴본 결과 초고압 처리구 모두 PSA와 항체와의 결합력이 약 98%로 높은 결합력을 유지하였으며 immunoblotting에서도 초고압 처리구의 PSA가 항체와 강하게 결합하였다. 이상의 결과를 종합해 볼 때 열을 배제한 microwave, 초음파 및 초고압 처리는 PSA의 항원성을 감소시키지 못하였으나 열을 배제하지 않은 microwave 처리는 시간이 증가함에 따라 PSA의 항원성을 크게 감소시켰으므로 이를 저 알레르기 돼지고기 식품 개발에 응용할 수 있을 것으로 사료된다.

• Preventive Nutrition and Food Science
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• 제5권3호
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• pp.126-130
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• 2000

To enhance the antitumor activity of Chinese cabbage kimchi, four kinds of kimchi, which ere differently prepared in kinds and levels of sub-ingredients, were fermented at 15$^{\circ}C$ for 1 day and then at 5$^{\circ}C$ up to pH 4.3. The solid tumor formation, hepatic glutathione S-transferase activity and glutathione contents in the liver, and natural killer (NK) cell activity of spleen were determined from the sarcoma-180 cell injected Balb/c mice that were treated with methanol extracts of the kimchi samples. Kimchi IV, prepared with organically cultivated Chinese cabbage, red pepper powder, garlic, Chinese pepper powder mustard leaf and heat processed salt (Gueun salt), reduced the tumor formation by 39.3% compared to the sarcoma-180 cell treated group, resulting in the smallest tumor weight. Methanol extracts of the kimchi III and kimchi IV recovered the activities of hepatic glutathione S-transferase(GST) that was decreased by the transplantation of the sarcoma-180 cells to th mice. The injections of methanol extracts of kimchi II and kimchi IV increased glutathione contents in sarcoma-180 cells treated mice. The methanol extract of kimchi IV increased the natural killer (NK) cell activity of spleen lymphocytes a more effectively (p<0.05) than those the other kimchi samples. These results suggest that the anticancer activities of kimchi can be increased by changing the kinds and levels of sub-ingredients.