• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.295-300
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• 1987

This experiment was carried out to review the chemical composition and microbiological aspects of seasonal raw milk collected from the dairy plants in Kangwon, Kyunggi, Seoul, Chungbuk, Chungnam, Jeorbuk, Jeonnam, Kyungbuk and Kyungnam of Korea. The results were summarized as follows: 1. The average composition of raw milk produced during spring season in each area showed moisture 88.00%, protein 3.49%, fat 3.43%, lactose 4.37%, and ash 0.75% but in summer it showed moisture 88.30%. protein 3.28%, fat 3.32%, lactose 4.26%, and ash 0.70%. 2. The microbiological aspects of raw milk in spring season showed viable bacteria counts $3.7{\times}10^6$, coliforms $2.2{\times}10^5$, thermoduric bacteria $1.4{\times}10^5$, thermophiles $1.4{\times}10^5$, psyclrotrophic bacteria $8.2{\times}10^5$, mould and yeast $1.9{\times}10^4$ per milliliter but in summer it showed viable bactteria counts $3.7{\times}10^6$, coliforms $2.3{\times}10^5$, thermoduric bacteria $2.3{\times}10^5$, thermophiles $7.5{\times}10$, psychrotrophic bacteria $5.0{\times}10^5$, mould and yeast $1.3{\times}10^4$ per milliliter.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1323-1328
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• 2000

Bovine colostrum, which contains a large quantity of immunoglobulins, is indispensable for newborn animals. The establishment of a new procedure for preserving colostrum without losing the immunological activity is significant. We examined the effect of high hydrostatic pressure treatment (100~500 MPa) on the preservability and the immunochemical activity of bovine colostrum. When high hydrostatic pressure treatment was 300 MPa or more, the increase of the total viable count, coliforms and psychrotrophic gram-negative bacteria was suppressed effectively. In particular, the number of coliforms in colostrum treated at 300 MPa or more hardly increased for 35 days at $4{^{\circ}C}$. At 400 MPa or more, both gelling of the colostrum and denaturation of immunoglobulins were observed. However, if the pressure was 300 MPa, immunoglobulins were scarcely influenced and the neutralizing titers against the bovine coronavirus did not decrease. Therefore, it was suggested that 300 MPa was the best pressure for good preservability of colostrum without reducing the immunochemical response.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.129-137
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• 2018

Objective: The objective of this research was to evaluate the physico-chemical, microbiological and sensorial qualities of restructured steaks processed from beef trimmings (grade I and II) and frozen beef (fresh beef as control and frozen beef). Methods: Beef trimmings from commercial butcher were collected, designated into 4 treatments differing in beef trimmings grade and freezing, processed into restructured steaks with 1% microbial transglutaminase and then analyzed for product quality. Results: The results showed that all meat from different groups could be tightly bound together via cross-linking of myosin heavy chain and actin as observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Microbial counts of psychrotrophic and mesophilic bacteria were not affected by treatments (p>0.05), and no detectable of thermophilic bacteria were found. Regarding effect of beef trimmings grade, steaks made from beef trimmings grade II (16.03% fat) showed some superior sensorial qualities including higher tenderness score (p<0.05) and tendency for higher scores of juiciness and overall acceptability (p<0.07) than those made from beef trimmings grade I (2.15% fat). Moreover, a hardness value from texture profile analysis was lower in steaks processed from beef trimmings grade II than those made from grade I (p<0.05). Although some inferior qualities in terms of cooking loss and discoloration after cooking were higher in steaks made from beef trimmings grade II than those made from beef trimmings grade I (p<0.05), these differences did not affect the sensory evaluation. Frozen beef improved the soft texture and resulted in effective meat binding as considered by higher cohesiveness and springiness of the raw restructured product as compared to fresh beef (p<0.05). Conclusion: The results indicated the most suitable raw beef for producing restructured steaks without detrimental effect on product quality was beef trimmings grade II containing up to 17% fat which positively affected the sensory quality and that frozen beef trimmings increased tenderness and meat binding of restructured beef steaks.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.548-553
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• 2004

Patties were prepared using Barbari male goats meat (age about 4 yrs) and packed in HDPE under vacuum (VP) and aerobically (AP). Packed patties were stored at 4$\pm$1$^{\circ}C$ and evaluated for physico-chemical, microbiological and sensory changes on days 0, 5, 10, 15, 20 and 25. Overall mean water activity ($a_{w}$), moisture (%), fat (%), pH, TBA number and W-B shear force values (kg/$cm^{2}$) of patties were 0.983, 61.93, 18.39, 6.38, 0.150 and 0.86, respectively. Except pH that was significantly higher and TBA number significantly lower in VP patties, treatment had no significant (p>0.05) effect on other physico-chemical traits. However, storage period significantly (p<0.05) affected physico-chemical traits. Moisture (63.79%) and $a_{w}$ (0.985) were significantly (p<0.05) higher on day 25. Patties became firmer on day 20 onwards as indicated by higher W-B shear force. Though packaging method had no significant effect, storage period influenced microbial counts. The standard plate counts (SPC), which were initially log 5.98 CFU/g decreased significantly (p<0.05) on day 10 followed by steady increase and reaching log 4.89 on day 25. Almost similar trend was observed for psychrotrophic bacteria counts. Lactic acid bacteria counts declined as the storage period progressed. Coliforms, and yeast and mould counts were either not detected by the method used or were very low in numbers. All samples of AP patties revealed swollen, greasy and sticky surface with spongy texture on day 20 whereas only some of the VP patties shown such changes on day 20. Results indicated that vacuum packaging had definite advantage in preserving the sensory quality of patties than aerobic packaging but it did not help in extending the shelf-life beyond 15 days.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.1
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• pp.69-74
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• 1986

In order to examine the effect of 'Lactobacillus plantarum' inoculation on the maturation of cured loin ham, bacteriological and biochemical changes in meat were investigated during curing periods. The results were summarized as follow; On the bacteriological changes of cured ham, during curing periods, the number of coliform group were decreased. while psychrotrophic and halo-tolerant bacteria were increased until the 4 days. In the brine solution after the 7days of the curing, the number of coliform group were decreased the 7 days, but psychrotophic and halo-tolerant bacteria were increased until the 7 days of curing. The pH value of the meat and curing solution were sharply decreased at the one day, since these were slightly increased from 4 days. The color development of cured meat was showed 84.05 % development of within the 7 days of curing. Glutamic acid contents among the 17 kinds of amino acid were the highest at the 7 and 10 days of curing. The 13 kinds of fatty acids detected from at the all sample and total contents of unsaturated fatty acid were slightly decreased during curing.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.1
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• pp.23-29
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• 1977

Three kinds of samples, Trachpenalus curiviostris, Astroconger myriaster and Cantherines modestus which were pre-treated in a processing plant were frozen at $-40^{\circ}C$ in a contact freezer and stored for 32 days.The numbers of general bacterium, coliforms and E. coli were measured at 8 day intevals during frozen storage and the isolated strains was classified. The results are as follows; 1. The numbers of coliforms and E. coli in the samples before freezing were much higher, than those during frozen storage and it tended to decrease. 2. General bacteria showed little change in number before and after being frozen. Among 97 strains of isolated coliforms, only 4 strains of K. aerogenes I ana 4 strains of K, cloacae were classified and the rest was not determined. 3. Ninety percent of coliforms was found to be psychrotrophic coliforms, which were able to grow at $5^{\circ}C$ within a week. 4. Vibrio and Pseudomonas were superior in number before freezing while Flavobacterium cytophaga and Moraxella were superior during frozem storage.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.517-521
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• 1988

This study focused on the psychrotrophic post-pasteurization contamination of fluid milk pro-ducts which were processed by HTST system. Pasteurized line samples and container samples of each fluid milk product (whole milk and skim milk) were taken in a large fluid milk plant. tine samples were collected through nine and five different sampling locations for whole milk and skim milk products, respectively. Each sample was subjected to preliminary incubation (PI) at 21$^{\circ}C$ for 16h followed by standard plate count (SPC) and crystal violet tetrazolium agar count (CVT). Flavor, SPC, and psychrotrophic bacteria count (PBC) were determined after 7 d at 7.2$^{\circ}C$. In addition, ten sequential container samples (packaged in 1000ml paperboard containers) were taken from a filler at the beginning of each product run. These samples were used for PI followed by SPC and CVT. In addition, flavor evaluations, SPC and PBC tests were conducted after 7,10, and 14 d at 7.2$^{\circ}C$. The mean PI-CVT values for the line samples showed differences depending on the location. There was major contamination between pasteurized storage tank and the filler. The PI-CVT counts for each container sample were negatively correlated with flayer scores at 10 and 140. There were good correlations among PI-CVT values of line samples and the percentage of total container samples with acceptable flavor after 10d.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.615-623
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• 1998

The garlic juices were extracted and concentrated by heating at $90^{\circ}C$, by using a rotary vacuum evaporator at $45^{\circ}C$, or by freezing at $-50^{\circ}C$ until the volume was reduced to 70% of the original volume. The concentrated juices were kept at $4^{\circ}C\;or\;25^{\circ}C$ for 60 days and the changes of bacteria and color were monitored every 10 days. Flavors of the raw garlic juices, concentrated garlic juices, and garlic powder by hot-air drying were analyzed monthly using GC and GC/MS. The CFUs/mL of mesophilic and psychrotrophic bacteria in the garlic juice concentrated at $90^{\circ}C$ were lower about 1 to 2 log cycles than those of other concentrated juices. Hunter L, a, and b values in the raw garlic raw juice and the juice concentrated at $-50^{\circ}C$ significantly increased at the beginning of storage, in particular, when they were stored at $25^{\circ}C$. The garlic juice concentrated at $45^{\circ}C$ showed relatively low L value but the juice concentrated at $90^{\circ}C$ showed high a value. The main peaks in chromatograms of volatile components identified by GC/MS were 3,3'-thiobis-1-propene, di-2-propenyl disulfide, 3-(methylthio)-1-propene in the raw garlic juice and the concentrated juices, and the juices concentrated at $45^{\circ}C\;or\;-50^{\circ}C$ showed relatively high preservation of garlic flavor.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.452-458
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• 1991

Psychrotrophs producing protease were isolated during ripening periods of Cheddar cheese and one of them containing the highest protease activity was identified as Pseudomonas fluorescens 65. The extracelluar proteolytic enzyme was partially purified from P. fluorescens 65 through the Sephadex G-100 gel filtration. The protease was eluted between 190 ml and 230 ml of elution volume of sodium phosphate buffer. The purified protease showed a single band in SDS-PAGE and its molecular weight was 47,000. The composition of amino acid for the protease was determined and the most abundant amino acids were glutamic acid (14.96%) and serine (13.86%). The optimum temperature and pH for the activity was $45{\sim}50^{\circ}C$ and 6.0, respectively.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.4
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• pp.412-421
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• 1998

Physicochemical and microbiological properties of red beans, soybeans, barleys, and corns irradiated by gamma-ray at 1.2 kGy, 10.1 kGy, or 30.5 kGy were investigated. Moisture content and crude lipid content of the irradiated cereals showed no significant difference from the nonirradiated group. TBA values of corns irradiated at 30.5 kGy increased. Gamma irradiation reduced the numbers of mesophilic and psychrotrophic bacteria in the cereals. Yeasts and molds were reduced below detection levels even at 1.2 kGy dose-irradiation. There was no significant difference in reducing sugars between the irradiated cereals and the nonirradiated ones except corns. Stachyose, raffinose, and sucrose of soy beans and sucrose of barleys increased by 30.5 kGy dose-irradiation. Loss of riboflavin content of the irradiated samples was not observed except red beans irradiated at 30.5 kGy. In Hunter's color, b value of the red bean powder increased but L value of the soybean powder decreased by the Irradiation. L, a, and b values of the barley powder slightly increased under 30.5 kGy dose-irradiation and b value of the corn powder decreased under 10.1 or 30.5 kGy-dose irradiation.