• Journal of Nutrition and Health
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• v.3 no.3
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• pp.137-140
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• 1970

The fatty acid compositions of cow's and human milk fats of Korea were compared by Gas-Liquid Chromatography(GLC) and general chemical compositions of their milks were also analyzed. Some similarities between human and cow's milk fatty acids were found. Human milk contained little butyric, caproic and caprylic acid were rich in linoleic acid. Cow's milk contained short chain fatty acids. Methylesters of the fatty acids were prepared by methanolysis.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.574-580
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• 1998

The technical feasibility of removing cholesterol from milk fat by supercritical carbon dioxide $(SC-CO_2)$ extraction followed by adsorption on different adsorbents and of fractionating milk fat into different fatty acid composition at $40^{\circ}C/276$ bar was investigated. Cholesterol could be selectively removed from milk fat by adsorption on a typical commercial florisil with $SC-CO_2$ extraction. Lower weight ratio of milk fat feed to florisil showed higher reduction of cholesterol, but gave lower yield in the milk fat fractions. The effective capacity of florisil for removing cholesterol from milk fat was 2.0g/g, which is the ratio of the fat feed to the adsorbent for 89% cholesterol reduction with a fat yield of 57.5%. Fatty acid composition showed higher short-chain and lower unsaturated long-chain fatty acids in the extracted fractions. Milk fat fractionation method by supercritical fluid extraction in coupled with adsorption would appear suitable for removing undesirable ingredients such as cholesterol and for enriching short-chain fatty acids in the fractions.

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.89-95
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• 1986

The five short-chain fatty acids such as isobutyric(C-4), butyric(C-4), isovaleric(C-5), valeric(C-5) and caproic (C-6) acids obtained from the extract of common purslane showed wide antifungal spectra against spore germination and mycelial growth of the twenty five phytopathogenic fungi tested in vitro, although there were differences in antifungal potency among them. The antifungal potency of each fatty acid varied significantly against different fungi in spore germination and mycelial growth. The seventeen fungi used for spore germination test and the sixteen fungi used for mycelial growth test can be divided into three groups depending upon differences in minimal inhibitory concentration of each fatty acid for them, respectively. Caproic acid was significantly more toxic to germination than to mycelial growth of the test fungi, while the other four fatty acids did not show such a significant differences in toxicity with a few of exceptions as shown in valerie acid. The longer the chain-length of fatty acid was, the higher the antifungal potency was shown. The normal fatty acids such as butyric and valerie acid were more toxic than their isomers to spore germination and mycelial growth of the test fungi. Each fatty acid was more toxic to spore germination of obligate parasites and some of facultative parasites, and mycelial growth of facultative parasites than to spore germination and mycelial growth of saprophytes, respectively.

• Korean Journal Plant Pathology
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• v.2 no.2
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• pp.82-88
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• 1986

Five antifungal substances were isolated from the long-term storaged extract of common purslane, and identified as isobutyric, butyric, isovaleric, valerie and caproic acids belonging to short-chain fatty acids (C4­C6). Each of these fatty acids showed more or less antifungal potency against spore germination and mycelial growth of Alternaria alternata Japanese pear pathotype in vitro. Antifungal potency of each fatty acid against spore germination was greater than that against the mycelial growth. No one of these fatty acids completely inhibited the mycelial growth at concentration lower than 200 ppm, while 50 ppm of caproic acid and 200 ppm of valerie acid completely inhibited the spore germination. The results of bioassay also suggested that chain-length of the fatty acids might be related with the antifungal potency, since fatty acids with longer chain showed higher antifungal potency.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1038-1044
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• 1997

The mode of the combined effect of adipic acid and medium chain monoglycerides was investigated by using nine strain. Though monoglycerides alone had little antibacterial activity against gram negative strains, the combined use with adipic acid showed much higher activity against others of gram positive strains as well as gram negative strains. But exceptionally, it seemed difficult practically to prevent the growth of lactic acid bacteria completely by the combined use of adipic acid and monoglyceride. For yeast and mold, monoglycerides alone had a high activity but adipic acid had a little activity. In antibacterial mechanism, we thought that adipic acid acted on the cell envelope and then monoglyceride acted on the altered cell.

• Journal of Animal Science and Technology
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• v.50 no.1
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• pp.111-120
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• 2008

The average milk fat content in goat milk was 3.88% on yearly basis. The milk fat content of 3.8% during summer season was lower than 4.2% during winter season. Total solid content increased in proportion to milk fat. When goat milk was stored at 4℃ for 24 hr, short-chain FFA(C4:0~C10:0) and medium- and long-chain FFA(C12:0~C18:1) increased about 106% and 203%, respectively. Induced lipolysis of goat milk by homogenization increased short-chain FFA and medium- and long-chain FFA by 22% and 199%. When goat milk was treated with calf lipase, there was increase of short-chain FFA by 9 times greater than increase of medium- and long-chain FFA by 5.6 times. Treatment with lipases from Candida rugosa and Pseudomonas fluorescens resulted in increase of medium- and long-chain FFA by 34 and 162 times, respectively, which was greater than increase of short-chain FFA by 6 and 14 times, respectively. Lipolysis in goat milk stored at 4℃ for 24 hr was correlated with LPL activity in goat milk(r=0.5635). Off-flavor of goat milk was correlated with LPL activity(r=0.5777). Milk fat content was negatively correlated with LPL activity(r=－0.4627). Palmitic acid content in goat milk was correlated with off-flavor(r=0.7226).

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.250.1-250.1
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• 2010

최근 석유공급 불안정성과 이산화탄소 배출 규제 움직임에 대응하기 위한 수단으로 바이오연료의 공급이 전세계적으로 증가하고 있다. 이와 같은 바이오디젤의 보급 활성화는 식물성 기름의 가격 상승과 수급 불안정 문제, 그리고 식량자원과의 충돌 문제를 야기하고 있다. 국내 바이오디젤 생산 원료로 사용되는 대두, 유채, 해바라기, 팜 등은 모두 식용시장과 수급 균형을 형성하고 있어 바이오디젤의 생산이 증가하게 되면 식용 오일 시장의 수급균형이 깨져 오일곡물 가격의 변동을 초래하게 될 것이다. 과거에는 수거비용을 들여 폐기하던 폐식용유 마저 이제는 돈을 주고 구입해야하는 실정에 다다랐다. 바이오디젤 생산비의 70~80%를 차지하는 원료유의 부족 현상에 따라 바이오디젤 업계에서는 soapstock, trapped grease, 폐식용유 등의 저급유지 활용 방안을 강구하고 있으며 자트로파와 같은 비식용 작물의 해외플랜테이션도 진행하고 있다. 본 연구에서는 커피찌거기에 남아 있는 오일을 속슬렛추출장치를 이용해 추출하고 전이에스테르화 반응을 수행하여 반응 특성과 커피오일 바이오디젤의 지방산 조성을 알아보고 바이오디젤 원료유로서의 사용가능성에 대해 알아보았다. 석유에테르를 용매로 속슬렛 추출장치를 이용해 추출시 원료대비 약 17%(w/w)의 오일을 추출할 수 있었다. 추출된 오일의 산가는 18.79mgKOH/g으로 매우 높아 직접 전이에스테르화 반응이 불가능하다. 고체 산 촉매 하에서 전처리 반응을 실시하여 유리지방산을 전환 제거한 후 염기촉매를 이용해 전이에스테르화 반응을 진행한 결과 약 80%의 바이오디젤(FAME) 함량을 얻을 수 있었다. 지방산 조성 분석 결과 리놀레익산(Linoleic acid, C18:2), 올레익산(Oleic acid, C18:1), 팔미틱산(Palmitic acid, C16:0)이 대부분을 차지하며 이 중에서도 리놀레익산이 44.17%로 가장 많은 함량을 보였다. 이는 커피찌꺼기 추출 오일이 바이오디젤 원료유로 활용 가능성을 나타내는 결과로, 색소성분 등의 불순물을 효율적으로 제거하여 증류정제 전단계에서의 바이오디젤 순도와 생산 수율을 증대시키기 위한 추가 연구가 필요한 것으로 판단된다.

• Journal of Korean Society on Water Environment
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• v.20 no.2
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• pp.183-189
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• 2004

The performance of a membrane-coupled anaerobic fermenter system for the recovery of volatile fatty acids (VFAs) from liquid organic sludge was experimentally investigated. Permeation flux was stably kept around $0.2(m^3/m^2/day)$ during operational period. The membrane-coupled fermenter showed 2.2 times higher VFAs concentration and higher VFAs forming rate than those of fermenter without membrane. The fermenter with membrane proved to be an effective system for the recovery of soluble organic materials from liquid sludge.

• Food Science of Animal Resources
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• v.32 no.1
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• pp.68-76
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• 2012

Olive oil and grape seed oil (10% of meat weight) were added to a package of beef loin. The package was then vacuum-sealed, and high pressure was applied (HP, 600 MPa) to investigate the effect of the penetration of vegetable oil into meat and safety and quality of the meat. Non-HP (0.1 MPa) without any oil treatment was considered as a control. The color $L^*$ and $b^*$-values of beef loin were higher and the $a^*$-value was lower than those of the control after HP at 600 MPa. The total aerobic bacterial number was 3 Log CFU/g in the control but no viable cell was detected in the beef with 600 MPa. All inoculated E. coli and L. monocytogenes were inactivated by HP. The beef loin with vegetable oil added without HP did not show any difference in fatty acid composition, but that treated by HP showed a higher oleic and linoleic acid content when olive oil and grape seed oil were added, respectively. The addition of olive oil inhibited lipid oxidation, and sensory evaluation revealed that there was no difference among treatments. The results indicate that the addition of vegetable oil followed by the application of HP enhances the safety of beef loin, changing the fatty acid composition in a health beneficial way. In addition, the use of olive oil can inhibit lipid oxidation induced by HP.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.795-799
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• 1989

This study was carried out to hydrolyze lactose in commercial milk by ${\beta}-galactosidase$ from Kluyveromyces fragilis and to compare some physicochemical properties of yoghurts made from control and lactase-treated commercial milks. Quantitative analysis of sugars was performed by gas liquid chromatograph (GLC) on trimethylsilyl (TMS) derivatives. In commercial milk, 94.6% of lactose was hydrolyzed after 2 hours incubation at $40^{\circ}C$ with 6.0 units/ml of ${\beta}-galactosidase$. pH, titratable acidity and viable cell number of yoghurt made from lactase-hydrolyzed (LH) commercial milk were 4.1, 1.04% and $6.5{\times}10^8/ml$ of Str. thermophilus, $8.9{\times}10^8/ml$ of L. bulgaricus after 8 hours incubation at $40^{\circ}C$, respectively, The total contents of amino acid were 2.63% in control and 2.19%. in LH yoghurt. The total contents of free amino acid were 26.95 mg% in control and 17.55mg% in LH yoghurt. Analysis of free fatty acids resulted in that the contents of short chain fatty acids in LH yoghurt were a little higher than those in control. Both in control and LH yoghurt, the palmitic acid content was highest and that was followed by oleic and myristic acid.