• Title/Summary/Keyword: storage bacteria

Search Result 1,064, Processing Time 0.033 seconds

Changes of Yeasts and Bacterial Flora during the Storage of Korean Traditional Makgeolli (전통 막걸리의 저장중 효모와 세균의 변화)

  • Min, Jin-Hong;Baek, Seung-Ye;Lee, Jong-Soo;Kim, Ha-Kun
    • The Korean Journal of Mycology
    • /
    • v.39 no.2
    • /
    • pp.151-153
    • /
    • 2011
  • In order to optimize storage conditions of Korean traditional Makgeolli, we brewed Korean traditional Makgeolli for 1 week with two-stage fermentations and investigated changes viable cell counts of yeasts and bacteria during storage for 1 month at $4^{\circ}C$ and $20^{\circ}C$. Yeast viable cell counts were decreased to 89.0% after storage for 30 days at $20^{\circ}C$, however, those were not significantly changed at $4^{\circ}C$ storage. Bacteria cell counts were decreased to 59.0% of initial cell counts for 30 days at $4^{\circ}C$. In the storage at $20^{\circ}C$, bacteria were significantly decreased to 98.0% of initial cell counts after storage for 30 days. Lactic acid bacteria were also similar to those of total bacteria cell counts at $4^{\circ}C$ storage, however, 99% of lactic acid bacteria were decreased at $20^{\circ}C$ storage for 30 days.

Change of Total Bacteria, Lactic bacteria and Textural Parameters during Kimchi Preservation (김치저장중 총세균.유산균 및 물성변화에 관한 연구)

  • 임국이
    • Journal of the Korean Home Economics Association
    • /
    • v.25 no.4
    • /
    • pp.57-62
    • /
    • 1987
  • To obtain basic data for the decvelopment of Kimchi preservation method, optimal ripening Kimchi was air-packaged with polyethylene bag, and followed by the microbiological, firmness and sensory evaluations during storage at 5$^{\circ}C$. 1. Total aerobic count increased in the beginning of storage and then decreased slowly as the number of total Lactic bacteria(anaerobe) in creased. 2. Textural parameters were remarkably changed according to the elapse of storage period. 3. Sensory evaluation showed that the score was decreased considerably 10 days after storage.

  • PDF

The Effect of Various Cereal Flours on Quality and Storage Characteristics of Sausage (곡류가루 첨가가 소시지의 품질 및 저장성에 미치는 영향)

  • 조은자;장선문;임지숙
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.14 no.3
    • /
    • pp.265-274
    • /
    • 2004
  • To investigate the effect of cereal powders on the quality and storage characteristics of sausage, Aw, pH, microbial count, TBA value, VBN value, textual and sensory characteristics were examined. Water activity tended to decrease as storage time prolonged and all the samples showed higher Aw's than that of the control. During the storage period, pH values of all the samples decreased. L, a and b values had a tendency to decrease during the storage period. During the four weeks storage at 4$^{\circ}C$, TBA and VBN values of all the sample showed increasing tendency and were lower than those of the control. Total plate counts of bacteria, the number of lactic acid bacteria and coliform bacteria counts increased as the storage time prolonged. Texture characteristics of all samples increased up to 1 week storage and decreased subsequently. The sensory scores of all the samples decreased as the storage time prolonged.

  • PDF

Quality of Milk and Psychrotophic Bacteria (우유의 품질과 저온성균)

  • Chung, Chung-Il
    • Journal of Dairy Science and Biotechnology
    • /
    • v.18 no.1
    • /
    • pp.38-46
    • /
    • 2000
  • Since generalization of cold storage of raw and processed milk, psychrotrophic bacteria has become more important. The number present in raw milk is related to sanitary conditions during pro-duction and to length and temperature of storage before pasteurization. Growth of psychrotrophs In raw milk often reduces the quality of pasteurized products. Recently, some pathogenic bacteria like Listeria monocytogenes, Yersinia enterocolitica, Bacillus cereus are reported to grow at low temperature and cause food poisoning. The presence of gram positive psychrotrophic bacteria which can survive pasteurization can limit the shelf life of pasteurized milk during extended storage and the survival of heat stable proteases and lipases produced by gram negative psychrotrophic bacteria often brings about proteolytic damage to milk protein in the products. Therefore, in order to prevent the deteorioration of milk and milk products by the growth of psychrotrophs, it is necessary to cool down the temperature of raw milk as soon as possible after milking and to keep the temperature below 5t during storage at farm. As psychrotrophic bacteria become readily predominant in raw milk under refregeration, it can be considered to change the traditional incubating temperature for SPC from 30${\sim}$32$^{\circ}C$ to 25${\sim}$27$^{\circ}C$ at which the psychrotrophs prefer to grow. The psychrotrophic bacterial count(PBC) is of limited use in dairy industry, because of the 10 days incubation period. Although estimates of psychrotrophic bacteria may provide an acceptable shelf-life prediction, there is no single, generally acceptable rapid method for replacing the PBC at the moment. Consequently, faster method for esmating psychrotrophic bacteria has to be developed.

  • PDF

The Microbiological Quality Estimation of Samul Chol-Pyon during the Storage (사물절편의 미생물학적 품질안전성)

  • 김윤선;박춘란
    • Korean journal of food and cookery science
    • /
    • v.18 no.5
    • /
    • pp.516-521
    • /
    • 2002
  • This study was investigated to prove the relation between the ingredient of Samul Chol-Pyon and its microorganism pollution level during the storage. As a result, the pollution degree in total aerobic bacteria, yeast, mold, and colitis germs of rice power turned out to have a lower one than the oriental medicine materials do. In case of preserved write Chol-Pyon, the total aerobic bacteria pollution level was 8.8 $\times$ 10$^3$CFU/g the highest degree among other ones in their among other ones in their early pollution levels and in the oriental medicine materials, the pollution level was degreased as its annex increased. Moreover, yeast propagated fast in its first day of storage, but mold grew somewhat slowly than yeast and total aerobic bacteria did. In every case, the range of colitis germs growth was between 10$^2$-10$^3$CFU/g and it was similar to the each one of total aerobic bacteria, yeast, and molds. On its third day of storage, the pollution level of mold showed 10$^4$-10$\^$5/CFU/g.

Chemical Changes during the Storage of Sweet potatoes Crushed and Sealed up with Polyethylene Film (파쇄(破碎)고구마의 밀봉저장중(密封貯藏中) 화학성분(化學成分)의 변화(變化))

  • Kim, Seung Kyeom;Kim, Seong Yeol
    • Korean Journal of Agricultural Science
    • /
    • v.11 no.1
    • /
    • pp.45-52
    • /
    • 1984
  • Changes of chemical componts and populations of total bacteria and lactic acid bacteria were examined during a month-long storage of sweet potatoes crushed and sealed up with polyethylene film at $7-8^{\circ}C$. 1. Changes of starch, total protein, volatile acid and ammonia-nitrogen contents were li 2. In a three days, pH down and increase of non-volatile acid content were notable, populations of total bacteria and lactic acid bacteria were maximum. 3. Vitamic C and soluble sugar contents tended to be reduced during the storage and the leftover were 75-85% and 41-45% respectively. 4. ${\beta}$-Amylase activity decreased gradually and vanished 15-30days. 5. Variations of chemical compontents of the samples inoculated lactic acid bacteria were larger than non- treated to some extent. 6. As above results, mainly homo lactic acid fermentation was done in this storage condition.

  • PDF

Survival of Sanitary Indicative Bacteria Inoculated in Fish Muscle Homogenates during Freezing and Frozen Storage (어육에 접종한 위생지표세균의 동결저장중 변화)

  • CHOI Jong Duck;CHANG Dong Suck;KIM Young Man
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.19 no.4
    • /
    • pp.356-362
    • /
    • 1986
  • This experiment was designed to evaluate effects of freezing and frozen storage on survival of sanitary indicative bacteria in seafoods. Culture of bacteria such as Escherichia coli type I, Citrobacter freundii type I, Klebsiella aerogenes type I and Streptococcus faecalis was inoculated into homogenates of pollack, shrimp, and sardine frozen in a contact plate freezer at $-40^{\circ}C$ and chest freezer at $-20^{\circ}C$, stored at $-20^{\circ}C$, and then survival of the inoculated bacteria was determined over a period of 95 days. Coliform group was highly sensitive to freezing and frozen storage showing survival of about $2\%$ after 95 days of frozen storage at $-20^{\circ}C$, whereas Streptococcus faecalis was relatively resistant with $20\%$ survival rate. The sanitary indicative bacteria count was rapidly decreased in the early stage of frozen storage revealing 90 to $95\%$ loss of coliform group and 40 to $70\%$ loss in case of Streptococcus faecalis after 10 days storage. In determining recovery rate, most probable number (MPN) method gave more reproducible recovery of the tested strain than did the selected agar plate method.

  • PDF

Populations of Fungi and Bacteria Associated with Samples of Stored Rice in Korea

  • Oh, Ji-Yeon;Jee, Sam-Nyu;Nam, Young-Woo;Lee, Ho-Joung;Ryoo, Mun-Il;Kim, Ki-Deok
    • Mycobiology
    • /
    • v.35 no.1
    • /
    • pp.36-38
    • /
    • 2007
  • Stored rice was collected from rice processing complexes of National Agricultural Cooperative Federation of 11 regions in Korea to evaluate the occurrence of fungi and bacteria and to identify the predominant fungi and bacteria to the genus levels. Most rice samples generally produced the higher levels of fungi and bacteria than white rice. The occurrence of fungi and bacteria varied in various locations of Korea. Among fungi observed, Aspergillus spp. and Penicillium spp. were dominant in the samples and Aspergillus spp. were observed more frequently than Penicillium spp. Predominant bacteria from rice and white rice samples tentatively belonged to the Genus Bacillus, Pectobacterium, Pantoea, and Microbacterium according to BIOLOG and FAME analyses. The results of this study showed that rice in Korea was contaminated in a relatively high level by two dominant storage fungi such as Aspergillus spp. and Penicillium spp. In addition, occurrence of mycotoxins in rice by the fungi could be possible and thus it is necessary to control the storage fungi.

Free Fatty Acid Accumulation by Mesophilic Lactic Acid Bacteria in Cold-Stored Milk

  • Coskun, Hayri;Ondul, Eda
    • Journal of Microbiology
    • /
    • v.42 no.2
    • /
    • pp.133-138
    • /
    • 2004
  • This study was aimed to determine the accumulation of free fatty acid by mesophilic lactic acid bac-teria (Lactococcus lactis subsp. lactis 1471, Lactococcus lactis subsp. cremoris 1000 and Lactobacillus casei 111) in cold-stored milk. According to the results, all cold-stored milks had higher acid degree val-ues than those of fresh milk. This phenomenon showed that a slight increase occurred in the accumulation of free fatty acids as a result of spontaneous lipolysis during cold storage. All lactic acid bacteria showed good performance in production of titratable acidity, which increased during fermentation of the milk (fresh and stored milks). Moreover, as the storage time was prolonged, more free fatty acid accumulation was obtained from the fermentation of the cold-stored milk by the investigated lactic acid bacteria. The control milk, which was without lactic acid bacteria, showed no change in the accumulation of free fatty acid during fermentation. From this result, it can be suggested that longer cold-storage time can induce higher free fatty acid accumulation in milk by lactic acid bacteria.

Bacteriological Characteristic of Atrina pectinata and Ruditapes philippinarum under Non-refrigerated and Refrigerated Storage Conditions

  • Kang, Kyoung-Ho;Kim, Byeong-Hak;Kim, Young-Hun
    • The Korean Journal of Malacology
    • /
    • v.24 no.1
    • /
    • pp.25-32
    • /
    • 2008
  • In order to estimate the necessity of refrigerated storage of fresh seafood for short-term storage, and evaluate the effect of refrigerated storage on pen shell Atrina pectinata and clam Ruditapes philippinarum collected from Jang-su of Deukryang Bay and I-mok of Sunchen Bay in South Korea, the counts of coliform, Escherichia coli and total aerobic bacteria in A. pectinata and R. philippinarum under non-refrigerated $(28{\pm}1^{\circ}C)$ and refrigerated storage conditions $(4{\pm}1^{\circ}C)$ were determined. The results indicated that the storage at temperature of $4^{\circ}C$ possessed significant effects on inhibiting bacterial growth in live seafood. And refrigerated storage had different effect on A. pectinata and R. philippinarum. Different species and culture environments significantly influenced the initial and ultima bacteria counts. This study confirmed that refrigerated storage for short-term storage of live seafood was necessary, and indicated that the effect of refrigerated storage was influenced by comprehensive effectors.

  • PDF