• 한국축산식품학회지
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• 제29권1호
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• pp.47-54
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• 2009

Predictive modeling was applied to study the growth of microorganisms related to spoilage in frankfurter sausage containing various levels of dietary fiber (0, 1, 2, and 3%) from rice bran and to estimate its shelf-life. Using the Baranyi model, total viable cells, anaerobic and psychrotrophic bacteria were measured during 35 days of cold storage ($<4{\pm}1^{\circ}C$). The lag times (LT) demonstrated by control and treatment groups were 6.28, 623, 6.24, and 6.25 days, respectively. The growth rate of total viable cells in each group were 0.95, 0.91, 0.92, and 0.91 (Log CFU/g/day), respectively. The anaerobic and psychrotrophic bacteria had lower initial ($y_0$) and maximal bacterial counts ($y_{max}$) than total viable cells. Also, the anaerobic and psychrotrophic bacteria possessed lower growth rate and longer lag time than total viable cells. The estimated shelf-life of frankfurter containing rice bran fiber by the growth rate of total viable cells was 7.8, 7.9, 7.9, and 7.7 days, respectively. There were no significant differences in shelf-life as a function of fiber content. In other words, the addition of dietary fiber in sausage did not show the critically hazardous results in growth of microorganism. The 12 predictive models were then characterized by high $R^2$, and small RMSE. Furthermore, $B_f$ and $A_f$ values showed a very close relationship between the predictive and observed data.

• 한국식품영양과학회지
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• 제32권3호
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• pp.413-417
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• 2003

빵 부패미 생물에 대한 녹차추출물의 항균활성을 조사하고 녹차가루를 첨가한 찐빵의 저장 중 항균효과를 알아보고자 하였다. 사용된 세균 3종류인 Bacillus subtilis ARCC 6633, Bacillus pumilus KCTC 3348, Bacillus cereus IFO 12113과 곰팡이 Aspergillus niger KCCM l1239 모두 GTE 1% 이상에서 우수한 항균력을 가지고 있으며, 생육이 억제됨을 확인하였다. GTE의 열 안정성은 넓은 온도 범위(50~20$0^{\circ}C$)에서 열을 가하지 않았을 때와 동일하게 항균력이 유지되었고, pH 사용범위 (4~9)에 관계없이 동일한 환으로 항균력을 나타내었다. 녹차를 첨가한 찐빵을 $25^{\circ}C$에 저장하면서 총 곰팡이 수와 총 세균 수를 측정한 결과 대조군, GTP 1%, 3% 첨가군 모두 저장 3일째에 곰팡이가 나타났으나 GTP 5% 첨가군에서는 저장 3일째에 나타났다. 총 세균 수는 저장 3일 이후 $10^{7}$ CFU/g을 넘어 부패가 진행 중이었으나 GTP 3%는 5일째에, GTP 5% 첨가군은 7일째에 $10^{7}$ CFU/g을 나타났다. 그러므로 찐빵에서의 녹차의 항균 효과에 따른 저장기간 연장은 녹차가루 첨가량 5% 이상의 수준에서 가능하리라고 추측된다.

• Journal of Dairy Science and Biotechnology
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• 제36권1호
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• pp.1-13
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• 2018

Kefir exhibits antimicrobial activity in vitro against gram-positive and gram negative bacteria, as well as some fungi. The ability of LAB to inhibit the growth of closely related bacteria is well known. This inhibition of pathogenic and spoilage microbes may be due to the production of organic acids, hydrogen peroxide, acetaldehyde, diacetyl, carbon dioxide, or bacteriocins. Lactobacilli are the major contributors to acid production and, hence, a determining factor in the flavor development in kefir. Lactic acid, proteolytic activity, and acetaldehyde are the essential flavor compounds in kefir. Both acid and bacteriocins contribute to the antimicrobial activity of kefir and kefir grains. Kefir is rich in proteins, calcium, vitamin $B_{12}$, niacin, and folic acid. Many studies have investigated the benefits of consuming kefir and have shown that it is a natural probiotic, which when consumed regularly, can help relieve intestinal disorders, promote bowel movement, reduce flatulence, and improve the overall health of the digestive system. Tibetan kefir, which is different from traditional kefir, is produced in China. It has been reported to exhibit antimicrobial activity that is nearly identical to that of traditional kefir. Kefir production is considered a rapidly growing food industry in China.

• 한국식품저장유통학회지
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• 제7권1호
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• pp.57-62
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• 2000

Ginseng was stored at a temperature lower than the freezing point after a treatment of freezing point depressing agents to extend its freshness. Respiration rate at freezing point of ginseng, -1.7${\pm}$0.1$^{\circ}C$, was inhibited 92% and 97% compared with those stored at 5$^{\circ}C$or 20$^{\circ}C$ , respectively. Sorbitol solution chosen as a freezing point depressing agent lowered the freezing point of ginseng to about -3.0$^{\circ}C$. Ginsengs treated with the sorbitol solution and packaged with 0.06mm LDPE was stored at -2$^{\circ}C$ , and the quality change was then compared with ginsengs stored at 0$^{\circ}C$ and 5$^{\circ}C$. Weight loss of ginsengs stored at -2$^{\circ}C$ for 100days was 1.5%, which is about 2.6times less than those stored at 5$^{\circ}C$. However, there were no significant difference between the ginsengs stored at -2$^{\circ}C$ and at 0$^{\circ}C$(1.9%). Spoilage rate of the ginsengs was 100% after 50 days of storage at 5$^{\circ}C$ and 25% after 100days at 0$^{\circ}C$respectively. but that of ginsengs stored at -2$^{\circ}C$ was 13%, which was half than that of ginsengs stored at 0$^{\circ}C$. Firmness and amount of monoscaccharides in ginsengs were decreased during storage at 5 or 0$^{\circ}C$ but ginsengs stored at -2$^{\circ}C$ showed better firmness and an increase in monosaccharides such as fructose and glucose. From above, when ginseng treated with freezing pont depressing agents were stored at -2$^{\circ}C$, the shelf life was extended to 2 or 3 times longer than those that were stored at 5 or 0$^{\circ}C$, respectively.

• 한국축산식품학회지
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• 제22권2호
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• pp.164-171
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• 2002

박테리오신을 생산하는 9종의 유산균 배양액으로부터 ammonium sulfate를 첨가하여 제조된 각각의 조박테리오신을 혼합하여 복합박테리오신용액을 제조하였다. 복합박테리오신의 항균 활성은 단일 박테리오신보다 우수하였으며 항균 범위 또한 넓어짐을 알 수 있었고 단일 박테리오신에 대하여 저항성을 나타내는 Listeria monocytogenes의 생육을 저해하는 것으로 나타났다. 또한, 복합박테리오신은 pH와 열에강한 안정성을 보여 식품 가공 중에도 이용이 가능한 것으로 나타났다. 복합박테리오신을 프랑크소세지, 모짜렐라 치즈 및 돈육등심근에 첨가한 후 저장기간별 일반세균수의 변화를 조사한 결과, 대조구에 비해 유의적인 감소현상을 나타내었고 저장 28일 경과 후에는 모든 식품에서 1/10 또는 1/100 정도로 식품내 총세균이 억제되었다. 또한, 저장기간 중 VBN의 함량을 조사한 결과 돈육등심근과 모짜렐라 치즈의 경우 14일 이후부터 박테리오신 처리구가 대조구에 비해 유의적으로 낮은 수치를 보여주었다.

• 한국식품영양과학회지
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• 제30권6호
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• pp.1011-1020
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• 2001

SDE 추출방법 과 GC-FID와 GC/MS 분석에 의하여 서로 다른 저장조건에서 부패된 양파의 휘발성 유기성분을 분석하였다. 생양파, 비가열부패양파, 반부패양파, 완전부패양파에서 각각 115, 143, 123, 137종의 화합물이 확인되었으며, 이들은 ester류, aldehyde류, ketone류, alcohol류, 황함유 화합물류들이었다. Dimethyl trisulfide, dimethyl disulfide, diprnpyl trisulfide, 3,5-diethyl-1,2,4-trithiolane는 생양파와 비가열부패양파에서 다량 확인되었으며, 양파가 부패도에 따라 휘발성 유기성분들 중 황함유 화합물류는 유의적으로 감소하였다. 황함유 화합물류를 제외한, 가열 후 반부패와 완전부패양파의 휘발성 유기성분은 주로 ester류, ketone류, alcohol류들이었으며, 특히 ketone류는 가열 후 완전부패 양파의 휘발성 유기성분의 구성에 큰 비중을 차지하고 있었다. 각각의 시료에는 170.3 mg/kg, 155.4 mg/kg, 121.2 mg/kg, 187.0 mg/kg 휘발성 유기 성분이 각각 함유되어 있었으며, 효소 불활성화에 의해 가열 후 반부패된 양파에서 휘발성 유기성분의 생성이 저하되었음을 알 수 있었으며,이를 계속하여 부패시킨 완전부패양파에서는 소량으로 함유되어 있던 휘발성 유기성분이 다시 증가되었음을 확인할 수 있었다.

• 한국식품영양과학회지
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• 제35권10호
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• pp.1456-1460
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• 2006

변질된 팥앙금에서 분리한 균주는 광학 및 전자현미경을 통하여 관찰한 결과 그람양성 간균으로 포자를 형성하고 형성된 집락은 원형으로 점질성의 물질을 생산하는 mucoid type이었으며, 표면은 smooth 하였고 광택을 나타내었다. 미생물 동정 시스템($MicroLog^{TM}$ System, Release 4)인 VITEK 2 COMPACT을 이용하여 분리된 균주의 46개의 생화학적 분석을 비교한 결과 팥앙금의 부패 원인균은 Bacillus subtilus로 동정 (97.0%)되었으며, 보다 더 정확한 동정을 위하여 부패균의 세포벽 지방산 조성을 분석하여 Midi sherlock시스템의 databank와 비교 분석시 그 유사성이 0.724로 분석되었다. Bacillus subtilus의 포자의 D-value는 $115^{\circ}C$에서의 4.85분이 었고, $121^{\circ}C$에서는 0.69분, $125^{\circ}C$에서는 0.48분이었으며, Z-value는 $9.71^{\circ}C$이었다. $45^{\circ}C$에서 수분활성도에 따른 분리균의 생육 상태를 관찰한 결과 수분활성도 0.92이하에서는 균이 증식되지 않았고, 0.94에서는 증식되는 것으로 관찰되었다.

• 한국환경농학회지
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• 제30권4호
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• pp.453-458
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• 2011

BACKGROUND: Coleosporium plectranthi, an obligate parasite, which is responsible for the rust disease of Perilla frutescens, a plant in Korea, commonly known as Perilla. All rusts are obligate parasites, meaning that they require a living host to complete their life cycle. They generally do not kill the host plant but can severely reduce growth and yield. Food and feed spoilage fungi cause great economic losses worldwide. It is estimated that between 5 and 10% of the world food production is wasted due to fungal deterioration. Rust disease of Perilla is highly frequent and is widely spread in Korea. The present study was designed to investigate a novel media for the urediniospore germination in vitro and anti-rust activity as well as GC-MS analysis of oak pyroligneous liquor. METHOD AND RESULTS: Urediniospores were collected from the infected leaf of Perilla. Spore suspension was made and the suspension was inoculated in the 2% water agar media with proper humidity, then they were incubated at $26^{\circ}C$ for 56 hrs. The GC-MS analysis of the oak pyroligneous liquor was also done to check the chemical composition. GC-MS analysis of the wood vinegar was found 15 compounds, among them o-mthoxyphenol (25.93%), 2,6-dimethoxyphenol (16.06%), 4-methylenecyclohexanone (10.69%), 2,3-dihydroxytoluene (7.84%), levoglucosane (6.14%) and propanoic acid (5.32%) were the major components. Different concentration of the oak pyroligneous liquor was used, and spore inhibition was recorded on the basis of spore counting. The best results were noted at the concentration of 50% solution where 31.8% spores were inhibited. CONCLUSION: On the basis of the chemical composition of the oak pyroligneous liquor and the activity recorded we can use it as an anti-rust agent.

• Journal of Biosystems Engineering
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• 제41권4호
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• pp.389-395
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• 2016

Purpose: Drying is one of the most widely used methods for preserving agricultural products or food. The main purpose of drying agricultural products is to reduce their water content for minimizing microbial spoilage and deterioration reaction during storage. Methods: Although numerous drying methods are successfully applied to dehydrate various agricultural products with little drying time, the final quality of dried samples in terms of appearance and shape cannot be guaranteed. Therefore, based on published literature, this review was conducted to study the drying characteristics of various agricultural products when different drying methods were applied. Results: An increase in the drying power of sources-for example, increase in hot air temperature or velocity, infrared or microwave power-and the combination of drying power levels can reduce the drying time of various agricultural products. In addition, energy efficiency in drying significantly relies on the compositions of the dried samples and drying conditions. Conclusions: The drying power source is the key factor to control entire drying process of different samples and final product quality. In addition, an appropriate drying method should be selected depending on the compositions of the agricultural products.

• 한국식품영양과학회지
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• 제30권5호
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• pp.865-869
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• 2001

메밀묵의 부패에 관련된 주요 미생물을 분리 동정하고, chitosan을 농도별(0, 0.5, 1.0, 1.5, 2.0%)로 첨가하여 메밀묵의 저장성과 품질에 미치는 영향을 조사하였다. 그 결과, 묵의 부패에 관여하는 주요균은 Serratia liquefaciens와 Staphylococcus lentus로 간주되었다. 메밀묵을 18$^{\circ}C$에서 6일간 저장시 chitosan의 첨가량이 1.5% 이상일 때는 균의 성장이 상당히 억제되었으며, 수분활성도 chitosan의 첨가량이 1.0% 이상일 때 변화가 적었다. 색상은 대조구와 chitosan 처리구 모두 뚜렷한 차이는 나타나지 않았다. 관능적 평가에서는 1.0% chitosan 처리구가 가장 좋은 것으로 평가되었으며 chitosan 농도가 1.5% 이상에서는 기호도가 떨어졌다. 따라서 메밀묵 제조시 chitosan을 1.0% chitosan 처리구가 가장 좋은 것으로 평가되었으며 chitosan 농도가 1.5% 이상에서는 기호도가 떨어졌다. 따라서 메밀묵 제조시 chitosan을 1.0% 첨가함으로써 대조구에 비하여 관능적 품질 향상뿐만 아니라 저장성도 1~2일정도 연장시킬수 있으리라 여겨졌다.