• Asian-Australasian Journal of Animal Sciences
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• 제22권11호
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• pp.1504-1512
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• 2009

A feeding trial was conducted to examine the effect of high-temperature-micro-time (HTMT) processing of diets containing extruded soybean (ESB) in high quantity on milk fat production, metabolic responses, and the formation of conjugated linoleic acid (CLA) and trans-vaccenic acid (TVA). Twenty-one multiparous Holstein cows in mid-lactation were blocked according to milk yield in the previous lactation. Cows within each block were randomly assigned to either normal concentrate or HTMT treated diets containing ESB (7.5% HTMT-ESB and 15% HTMT-ESB). It was hypothesized that the HTMT-ESB would affect the undegradable fatty acids in the rumen and, thus, would modify the fatty acid profile of milk fat. Both 7.5% and 15% HTMT-ESB did not affect milk yield, fat, protein, lactose and solid-not-fat (SNF), but the proportion of cis-9, trans-11 CLA in milk fat was significantly increased by these treatments. Content of TVA in milk fat was not affected by HTMT-ESB. The HTMT-ESB influenced the fatty acid profile in milk fat, but there was little difference between 7.5% and 15% of supplementation. HTMT-ESB feeding significantly decreased the concentration of plasma insulin and glucose, while plasma growth hormone (GH), triglyceride (TG), non-esterified fatty acid (NEFA) and HDLcholesterol were increased by 7.5% and 15% ESB-HTMT supplementation in comparison to the control group (p<0.05). However, no significant difference was observed in plasma LDL-cholesterol, insulin like growth factor (IGF)-1, T3, T4, and leptin concentrations among treatments (p>0.05). The present results showed that cis-9, trans-11 CLA production was increased by HTMT treatment of dietary ESB without reduction of milk fat, and the unchanged milk fat and yield was assumed to be associated with the constant level of thyroid hormones, leptin, and IGF-1.

• 한국식품영양학회지
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• 제7권2호
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• pp.151-158
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• 1994

This study was carried out to clear up the cause of low-acid producing phenomenon occurred In non-fat dry milk during liquid-yoghurt fermentation by Lactobacillus case, and to present its improving methods. All samples of non-fat dry milks which were low in TCA-soluble peptides showed low-acid production, but those high in TCA-soluble peptides showed high-acid production. The addition of trypsin-hydrolysate of Na-caseinate to non-fat dry milk showed some improving effect on acid production but that of papain-hydrolysate did not show any improving effect and that of bacterical neutral protease-hydrolysate showed some inhibitory effect. The improving effects on growth and acid production of lactic acid bacteria were more prominent when the trypsin-hydrolysate of Na-caseinate was added. to such fermenting system in which the levels of TCA-soluble peptides and the proteolytic ability of starter bacteria were abnormally low. The liquid-yoghurt made with non-hydrolysed Na-caseinate and defective non-fat dry milk showed precipitate occurrence but that with trypsin-hydrolysate of Na-caseinate and defective non-fat dry milk did not make any precipitate during storage as with normal non-fat dry milk.

• Asian-Australasian Journal of Animal Sciences
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• 제3권3호
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• pp.247-252
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• 1990

Nine Holstein cows in mid lactation period were utilized to examine the effect of recombinant bovine somatotropin (BST) of tow companies (Company A, Company B) on milk production and milk composition under the feeding conditions of Korea. Treatments were 0 (Control), 25 mg BST/day from company A (BST A) and 25 mg BST/day from company B (BST B) injected subcutaneously, once daily beginning at $200{\pm}20$ days postpartum and continuing for 28 days. Cows were fed ad libitum a total mixed diet throughout the experimental period. BST treatments increased average 4% fat corrected milk yields and milk energy output over the 28-day treatment period. However, no differences were observed in dry matter intake, gross efficiency, energy intake and percent milk energy. Although there was a tendency for increased milk fat percent, there were no differences in milk composition and yields of major milk components except for milk fat yield with BST injection. Somatic cells of all groups were also characteristic of a well managed herd. Neither mean body condition score nor body weight was significantly (p <0.05) changed before and during BST treatment. BST concentration in milk remained in the range of control animals throughout the experimental period of BST treatment. Results indicate that short-term injection of recombinant bovine somatotropin from two companies to lactating dairy cow resulted in similar increased in milk yield without alteration of major milk components or feed intake.

• 한국식품과학회지
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• 제4권3호
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• pp.213-223
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• 1972

This paper chose the methods of methylesterification of the use of methoxide, the mixture solution of methanol-benzen-sulfuric acid in transesterification of the fat in cow's milk and modified powder milk and separated by gas liquid chromatography with F.F.A.P., D.E.G.A. as liquid phase. Quantitative analysis of the fatty acid of milk fat in cow's milk and modified powder milk was determined by gas liquid chromatography using the method of temperature programming which should be used to obtain satisfactory separation of short chain fatty acid on the chromatogram. It was found that the fatty acid composition of cow's milk and modified powder milk are all the major fatty acid of milk fat obtained by GLC analysis. Main components was found to be from butyric acid to arachidonic acid showing Fig. 3, 4, 5 and Table 4, 5, 6, 7, 8, 9.

• Preventive Nutrition and Food Science
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• 제4권4호
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• pp.226-230
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• 1999

This study was done to determine how added vegetable oils affect the physical, chemical and microbial properties of experimental frozen desserts. There were no differences in the percentages of total fat and total solids in the seven frozen desserts. Freezing points did not differ among treatments. There were significant differences in viscosity among the frozen desserts containing up to 80% of vegetable oils. Oil substitution at 30% or higher significantly decreased viscosity when compared to the milk fat control. The hardness of frozen desserts decreased significantly with increasing addition of oils. Oil substitution at 20% or higher significantly decreased hardness. Substitution of canola and soybean oils for milk fat increased melting rate. Initiation of fluid release in the control was slower than in frozen products with added oils. The SPC values and coliform counts of all frozen products were not significantly changed. Cholesterol content decreased significantly in the products as the vegetable oil content was raised. Frozen desserts containing 10% or 60% of vegetable oils in the total fat contained 91.8%, 73.5% or 32.5%, respectively, of the cholesterol in the control.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.213-220
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• 2004

The purpose of this experiment was to investigate the effect of the diets supplemented with lard or prilled fat ($Carolac^{(R)}$) on lactation performance, plasma constituents and ruminal characteristics of Holstein cows under a warm climate. In trial 1, 18 Holstein cows, 14 primiparas at 43 DIM and 4 multiparas at 55 DIM, were randomly assigned into six $3{\times3}$ Latin squares, in which three dietary treatments were isoproteinous but varying in energy contents and three 21 d periods. The treatments were basal diet (Control), basal diet supplemented with 2.5% lard (LD), and basal diet supplemented with 2.5% commercial Prilled fat (PF). In trial 2, three rumen canulated pregnant nonlactating Holstein cows with 550 kg average body weight were allotted into a $3{\times}3$ Latin square design with diets same as in trial 1 were fed to the cows at the level of 1.5% body weight on dry matter (DM) basis. The results indicated that the DM intake did not differ among the treatments. Milk yield and 4% FCM yield were greater (p<0.05) in PF than in Control. LD and PF resulted in greater milk fat percentage. Protein, lactose and solid contents in milk were not different among the three dietary treatments. The concentration of nonesterified fatty acids (NEFA) in plasma was significantly greater in LD and PF than that in Control. However, the concentrations of triglycerides, urea nitrogen, and cholesterol in plasma were not significantly different among the three treatments. Although the ruminal molar percentage of isobutyrate in LD and PF was greater, no significant difference was observed in ruminal pH, NH3-N concentration and VFA production among the three treatments. Diet supplemented with fat can improve milk yield and milk fat percentage without resulting in disadvantages of ruminal characteristics in cows at early lactation and under warm climate.

• Journal of Dairy Science and Biotechnology
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• 제24권1호
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• pp.43-51
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• 2006

Producer prices of raw milk include following elements: a basic price, payment according to fat content, payment according to bacteriological quality and somatic cell count. The quality of raw milk has increased since last change of payment system according somatic cell count. But last change of payment system according to fat content is not effective. It is necessary to widen the range of equal price by fat content. Also it is necessary to include payment according to protein content.

• 한국식품위생안전성학회지
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• 제1권1호
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• pp.47-50
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• 1986

Sanitary condition for raw milk in Korea was investigated in this study. It is hoped that the information will be used for reference in future endeavors of study in the field of public health and food sanitation in Korea. The results were summerized as follows: 1) The viable cell counts of bacteria in raw milk were tend to be increased under the various atmospheric temperature, and the correlation coefficient between temperature and total viable cells was r=+0.921(p<0.01). 2) The correlation coefficient between methylene blue reduction time test and viable cell counts of bacteria in raw milk was r=-0.799(p<0.01). 3) The relationship between total solid rate(%) and milk fat rate(%) was highly significant level as r=+0.745(p<0.01). 4) Highly significant correlation coefficient was r= +0.945(p<0.01) between milk fat and protein rate in raw milk.

• Animal Bioscience
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• 제35권2호
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• pp.281-289
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• 2022

Objective: The aim of this study was to characterize the exopolysaccharides (EPS)-producing lactic acid bacteria from Taiwanese ropy fermented milk (TRFM) for developing a clean label low-fat fermented milk. Methods: Potential isolates from TRFM were selected based on the Gram staining test and observation of turbid suspension in the culture broth. Random amplified polymorphic DNA-polymerase chain reaction, 16S rRNA gene sequencing, and API CHL 50 test were used for strain identification. After evaluation of EPS concentration, target strains were introduced to low-fat milk fermentation for 24 h. Fermentation characters were checked: pH value, acidity, viable count, syneresis, and viscosity. Sensory evaluation of fermented products was carried out by 30 volunteers, while the storage test was performed for 21 days at 4℃. Results: Two EPS-producing strains (APL15 and APL16) were isolated from TRFM and identified as Lactococcus (Lc.) lactis subsp. cremoris. Their EPS concentrations in glucose and lactose media were higher than other published strains of Lc. lactis subsp. cremoris. Low-fat fermented milk separately prepared with APL15 and APL16 reached pH 4.3 and acidity 0.8% with a viable count of 9 log colony-forming units/mL. The physical properties of both products were superior to the control yogurt, showing significant improvements in syneresis and viscosity (p<0.05). Our low-fat products had appropriate sensory scores in appearance and texture according to sensory evaluation. Although decreasing viable cells of strains during the 21-day storage test, low-fat fermented milk made by APL15 exhibited stable physicochemical properties, including pH value, acidity, syneresis and sufficient viable cells throughout the storage period. Conclusion: This study demonstrated that Lc. lactis subsp. cremoris APL15 isolated from TRFM had good fermentation abilities to produce low-fat fermented milk. These data indicate that EPS-producing lactic acid bacteria have great potential to act as natural food stabilizers for low-fat fermented milk.

• 한국식품과학회지
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• 제30권3호
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• pp.574-580
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• 1998

유지방을 초임계 이산화탄소로 추출한 후 흡착제를 통과시켜 콜레스테롤이 제거되고, 지방산 조성이 다른 유지방 분획들을 얻기 위하여, 콜레스테롤 흡착능이 있는 것으로 알려진 몇 가지 흡착제를 선택하여, 추출온도 $40^{\circ}C$, 추출압력 276, 345 bar에서 3 또는 4시간 동안 추출하면서 흡착제의 종류별, 입자크기별, 비율별로 추출시간에 따른 유지방의 수율, 콜레스테롤 함량, 지방산 조성을 측정하였다. 흡착제로서 ${\beta}-cyclodextrin,\;talc,\;celite,\;florisil$ 중에서 florisil이 유지방으로부터 콜레스테롤 제거율이 가장 높았다. Florisil의 입자크기별로 콜레스테롤 제거율은 30/60 mesh가 가장 높았으며, 그 다음 100/200, 60/100 mesh순이었다. 유지방에 대하여 흡착제의 비율이 높으면 콜레스테롤 제거율은 높은 반면, 지방의 수율은 감소하였는데, 유지방의 수율을 높이면서 콜레스테롤 제거율을 높이기 위해서는 유지방과 흡착제의 비율은 20:10이 적당하였다. 추출분획물의 지방산 조성을 측정한 결과 저급 지방산들은 초기 추출물 분획들에 농축되었고, 고급 지방산들은 추출잔류물 분획에 농축되었다. 이상의 결과로부터 초임계유체 추출 및 흡착법은 유지방으로부터 콜레스테롤을 제거하는 동시에 저급지방산, 불포화지방산, 버터향, 색소가 농축된 분획 등을 얻을 수 있었다.