• 한국환경과학회지
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• 제17권2호
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• pp.211-224
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• 2008

Characteristics of the esterification reaction between free fatty acid in rice bran oil and methanol was investigated in the presence of catalysts, such as PTS(p-toluene sulfonic acid), Amberlyst 15 dry and SCX(silica gel based strong cation exchange resin). While reaction temperature was kept constant at $65^{\circ}C$, initial feed content of free fatty acid was varied from 100% to 1% by addition of pure free fatty acid which was previously made from rice bran oil. Also, the effect of mole ratio of methanol to fatty acid on the final conversion was examined. When esterification of pure free fatty acid was catalyzed by several acids, final conversions were increased in order of Amberlyst 15 dry, SCX and PTS. Using PTS catalyst, initially the reaction proceeded in homogeneous 2nd oder reaction mechanism. However, phase of reaction mixture changed from homogeneous to heterogeneous along the reaction time and then reaction rate was retarded by mass transfer resistance of methanol. Final conversion of free fatty acid in reaction mixture was depended on initial feed content of free fatty acid, and had maximum value at 30% of initial feed free fatty acid content for all kinds of catalysts used. And the final conversion was increased with mole ratio of methanol by the improvement of reaction rate. When initial feed free fatty acid content below 10% and the reaction was catalyzed by PTS, concentration of free fatty acid in reaction mixture was increased in the middle of reaction time by hydrolysis of triglyceride in reaction mixture. Also, if silica gel was added into the reaction mixture which had initial feed free fatty acid content below 50%, final conversion was increased by the adsorption of moisture produced. The SCX catalyst made the esterification reaction of free fatty acid to progress like in case of PTS catalyst. However, when initial feed free fatty acid content below 10%, concentration of free fatty acid in. reaction mixture was decreased monotonically and not increased in the middle of reaction time on the contrary to the case of PTS. Thus, SCX catalyst accomplished more high value of final conversion than PTS catalyst for the initial feed fatty acid content range from 50% to 5% In case of initial feed free fatty acid content of 1% and mole ratio of methanol was 2, concentration of free fatty acid in reaction mixture increased over the initial feed free fatty acid content for all kind of catalysts used. Although SCX catalyst was added into reaction mixture which had 1% of initial feed fatty acid content, final conversion was hardly raised by mole ratio of methanol.

• 한국식품영양학회지
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• 제37권2호
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• pp.123-127
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• 2024

The fatty acid composition and free amino acid content of domestic soybean cultivars were analyzed to confirm the quality characteristics of protein and fat contained in soybeans. The saturated fatty acid content of soybeans included palmitic acid at 9.47~11.15%, followed by stearic acid and myristic acid. The total saturated fatty acid content in soybeans was 12.56~14.34%, with Taekwang having the lowest content, followed by Daewon, Seonyu, Cheonga, and Jinpung. The linoleic acid content, an unsaturated fatty acid, was 45.69~58.17%, with Taekwang showing the lowest composition and Jinpung showing the highest composition. Next was oleic acid at 14.69~33.86%. Jinpung had the highest linoleic acid composition, had the lowest and Taekwang which had the least linoleic acid, had the highest. The unsaturated fatty acid content was in the order of linolenic acid, eicosatrienoic acid, eicosadienoic acid, and eicosapentaenoic acid. The total free amino acid content was 217.28~456.66 mg%, with Daewon showing the highest free amino acid content, followed by Seonyu, Taekwang, Cheonga, and Jinpung. The free amino acid content varied depending on the cultivars, but in general, the free amino acids in the soybeans used in the experiment showed higher aspartic acid, glutamic acid, and proline contents than other amino acids.

• 대한가정학회지
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• 제23권1호
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• pp.25-31
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• 1985

This study designed not only to elucidate free amino acid, fatty acid composition and mineral content in dried alaska pollack but also to examine calcium, magnesium, poassium and sodium contents in its cooking broth according to each boiling time such as 2.5, 5, 10, 20, and 30 minutes. RESULTS : 1. Glutamic acid in dried alaska pollack was the most abundant free amino acid and was followed in order of aspartic acid, lysin, leucine and histidine. They composed of 50.95% of the total amino acid contents. 2. In dried alaska pollack the most abundant fatty acid was palmitic acid. Essential fatty acid content was 26.57% of the total fatty acid. 3. The calcium, magnesium, potassium and sodium contents in dried alaska pollack showed 10.721 mg%, 9.235mg%, 4072.5mg% and 2299.8% respectively. The amount of magnesium and potassium in cooking broth arrived at the highest level when 20 minute boiling was undertaken and the quantities of magnesium and sodium were the highest when 30 minute boiling was made.

• Applied Biological Chemistry
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• 제29권4호
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• pp.346-351
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• 1986

이조대맥의 맥아제조시 유리 및 결합지질과 중성지질의 함량변화와 구성지방산의 변화를 조사하였다. 1. 이조대맥의 지질함량 27.9mg/g-d.w.중 유리지질과 결합지질이 각각 22.6, 5.3mg/g-d.w.으로서 유리지질이 대부분을 차지하였으며, 맥아제조시 발아일수가 경과함에 따라 다 같이 감소하였다. 2. 이조대맥의 중성지질의 함량은 21.0mg/g-d.w.으로서 전지질의 75% 정도 차지하였으며, 맥아제조시 발아일수가 경과함에 따라 감소하였다. 3. 이조대맥의 주지질인 중성지질의 조성은 triglyceride가 54.6%로 대부분을 차지하였으며, 다음으로 free fatty acid, free sterol, 1,2-diglyceride, 1,3-diglyceride순이었고, 이들 중 triglyceride는 발아기간중 감소하였으며, free fatty acid와 sterol ester는 증가하였다. 4. 유리지질 및 결합지질의 구성지방산은 다같이 linoleic acid가 50% 이상을 차지하였으며, 다음으로 palmitic acid, oleic acid 등이 주지방산이었다. 그리고 주지방산인 linoleic acid는 발아기간 중 증강이 뚜렷하지 않았으나 palmitic acid는 유리지질에서 증가하는 반면에 결합지질에서는 감소하였고, oleic acid는 유리지질에서 감소하는 반면 결합지질에서 변화하지 않아 뚜렷한 차이를 나타내었다. 5. 중성지질의 구성지방산 조성은 유리지질과 결합지질은 다같이 linoleic acid가 주지방산이었고 다음으로 palmitic acid, oleic acid순이었다. 발아과정중의 구성지방산의 변화는 palmitic acid가 증가하는데 비하여 주지방산인 linoleic acid나 stearic acid가 다소 감소하는 경향이었다.

• KSBB Journal
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• 제30권2호
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• pp.91-95
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• 2015

Production of biodiesel from microalgae is dependent on the microalgal lipid content and free fatty acid composition. Both lipid and free fatty acid are regulated by nutrient sources. In this study, newly developed mutant Chlamydomonas reinhardtii with higher lipid content was investigated for the effect of nutrient limitation. Nitrogen $NO_3{^{-}}$ and phosphate $PO_4{^{3-}}$ were limited for nutrient starvation during the cultivation. Under nutrient starvation, total lipid content level was increased to 27~33% and C16:0 fatty acid content constituted over 31~43% of total fatty acid. Interestingly, we also found that the expression of fatty acid desaturase (FAD7) was decreased when nutrients were starved.

• 한국식품과학회지
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• 제21권1호
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• pp.17-24
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• 1989

가열처리 및 건조방법이 새우의 지방질 함량과 중성지방질에 미치는 영향을 밝히고자 하였다. 생새우의 총지방질 함량은 건물기준으로 6.0%였으며, 가열 및 건조방법에 따라 총지방질의 함량은 유의적인 변화가 없었다. 생새우의 중성, 당 및 인지방질의 함량비는 각각 36.8:21.5:41.7% 이었고 동결건조한 것은 열풍건조한 것보다 중성시방질의 함량이 유의적으로 많은 반면에 당 및 인지방질의 함량은 적었다. 중성지방질의 주요성불은 triglyceride, free sterol, free fatty acid 및 esterified sterol이었으며, 동결건조한 것은 열풍건조한 것보다 triglyceride 함량은 유의적으로 많았고 free fatty acid 함량은 적었는데, 이는 열풍건조중 triglyceride가 분해된 것으로 생각되었다. 생새우의 총지방질의 구성 주요지방산은 palmitoleic acid, eicosapentaenoic acid 및 docosahexaenoic acid이었고, 중성지방질의 구성 주요 지방산은 palmitic acid, palmitoleic acid, oleic acid, eicosapentaenoic acid 및 docasahexaenoic acid이었다.

• 한국의류학회지
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• 제5권1호
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• pp.15-21
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• 1981

The effect of fatty acid content in oily soil and conditions of washing on the removal of triglyceride have been studied. Cotton lawn was soiled with the four-component soil-tripalmitin, palmitic acid, dodecyl alcohol and dodecane-and washed in constant temperature waterbath shaker. The detergency was estimated by analysis of triglyceride labelled carbon-14 on fabrics before and after washing by means of liquid scintillation counting. It was shown that the detergency of triglyceride washed with the nonionic, nonylphenol poly (10)-ethylene oxide and soap was increased steadily with increasing temperature, whereas with the anionics Na-DBS and SLS, the detergency was rather decreased when the temperature was elevated above $40^{\circ}C$. To investigate the effects of free fatty acid content in soil on the removal of triglyceride, the fabrics were soiled altering palmitic acid content, and then washed. From the results, the detergency of triglyceride was developed with increasing free fatty acid content. With soils containing less than $30\%$ of free fatty acid, of the three detergents tested, the nonionic was by far the most effective soil removal. Soap was intermediate and the synthetic anionic was the poorest. With soil containing $45\%$ of free fatty acid, soap was the most effective soil removal. When NaOH was added to detergent solution. the detergency of triglyceride was improved without regard to detergents. The optimum alkalinity was obtained according to free fatty acid content. And the alkalinity changed to low NaOH concentration with increasing free fatty acid content. From the results mentioned above, it could be concluded that the major removal mechanisms of triglyceride containing oily soil were mesomorphic phase formation, solubilization and soap forma-tion when alkali was added in detergent solution.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.541-543
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• 2006

The feasibility of biodiesel production from soapstock by acid catalyst was tested. The water content of soapstock was more than 40%. Before the esterification of soapstock, the pre-treatment of soapstock was conducted adding potassium hydroxide and sulfuric acid. The pre-treated soapstock contained 99.6wt% of free fatty acid. When the free fatty acid was esterified with methanol, the fatty acid methyl ester content became 91.7wt% under the solid acid catalyst, Amberlyst-15. When this biodiesel was distilled the methyl ester content was 98.1wt% which satisfied the biodiesel Standard. Amberlyst-15 could be recovered easily because it was the soliid catalyst. When sulfuric acid was used as the acid catalyst, the fatty acid methyl ester content was 91.0wt%. From the results, it was possible to produce biodiesel efficiently from soapstock after pre-treatment. Because soapstock is very cheap, it will become good feedstock for biodiesel product ion.

• 한국식품과학회지
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• 제17권4호
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• pp.271-275
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• 1985

녹두(綠豆)를 7 일간(日間) 발아(發芽)시키면서 2 일(日)간격으로 자엽부(子葉部)와 배축부(胚軸部)의 조지방량(粗脂肪量), 구성지방질(構成脂肪質) 및 구성지방산(構成脂脂酸)의 변화(變化)를 연구(硏究)한 결과(結果) 녹두발아(錄豆發芽)중 자엽부(子葉部)와 배축부(胚軸部)의 조지방질(粗脂肪質)은 다 같이 감소(減少)하였는데 감소(減少)정도는 자엽부(子葉部)에서 더 심하게 나타나며 자엽부(子葉部)의 triglyceride는 계속 감소(減少)하였고 free fatty acid의 함량(含量)은 계속 증가(增加)하였으나 배축부(胚軸部)에서는 반대(反對)경향을 보였다. sterol은 자엽부(子葉部)에서 증가(增加)했고 배축부(胚軸部)에서는 약간씩 감소(減少)경향을 나타냈으며 인지질은 배축부(胚軸部)에서 약간의 증가(增加) 현상(現狀)을 나타냈고 자엽부(子葉部)에서는 계속적으로 감소(減少)하였다. 발아(發芽)중 자엽부(子葉部) 및 배축부(胚軸部)의 구성지방산(構成脂肪酸)은 불규칙하게 변화(變化)했고 자엽부(子葉部)에서는 linoleic acid가 배축부(胚軸部)에서는 stearic acid가 주요(主要) 구성지방산(構成脂肪酸)으로 나타났다.

• 한국식품영양학회지
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• 제17권2호
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• pp.206-211
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• 2004

오리 난황유는 난황을 성형 증자하여 만든 증자난황을 일정 조건 하에서 건조 후 용제 추출하여 제조하게 된다. 이때 증자 난황의 건조가 유제품의 품질에 집적적인 영향을 미치게 된다. 따라서 청둥 오리알로부터 직접분리 조제한 난황으로부터 난황유 추출 및 저장과정 중에 일어나는 유지의 품질 변화를 방지하기 위하여 오리난황유의 추출 이전 단계인 증자 난황의 건조 방법 및 수분함량, 온도, 건조 시간에 따른 산가 및 수분 함량의 변화를 조사한 결과, 열풍건조 분무건조 및 동결건조에 따른 산가는 각각 3.7, 3.5 및 3.5였으며, 수분의 함량은 각각 4.0%, 3.0%, 3.0%이었고, 유리지방산의 함량은 각각 0.83%, 0.80% 및 0.79%로 동결건조 및 분무 건조에 의한 건조 시 비교적 낮은 산가 및 수분함량을 보였으나 각 건조 방법 간의 유의한 차이는 보이지 않았다. 건조 온도의 영향은 6$0^{\circ}C$에서 수분의 함량은 최저치에 도달하여 일정한 값을 보인 반면, 산가 및 유리 지방산의 함량은 추출온도가 60%이상에서 급격히 증가하는 결과를 보였다. 건조시간에 따른 산가 및 수분함량과 유리 지방산의 함량 모두 건조 9시간 후 각각 3.1, 3.0% 및 0.98%로 최저값에 도달하여 건조 12시간까지 변화를 보이지 않았다. 또한 산가에 따른 난황유 지방산 조성의 변화는 $C_{18:0}$(stearic acid)의 함량은 산가가 1.5 증가함에 따라 4.76%에서 7.11%로 약 1.5배 가량 증가한 반면 불포화 지방산의 함량은 급격히 감소함을 보였다. 불포화 지방산 중 함량이 많은 지방산의 감소폭이 커짐을 보였다. 불포화 지방산 중 linolenic acid( $C_{18:3}$)의 경우 1.29%에서 0.96%로 약 3배 가량 감소되었으며, Arachidonic acid($_{20:4}$)의 경우 0.63%에서 0.40%로 약 1.5배 가량 감소되었다. 이상의 실험결과로부터 최적의 증자난황 건조조건으로 열풍건조법으로 6$0^{\circ}C$, 9시간 건조시 수분함량과 산가 및 유리지방산이 함량이 낮은 양호한 품질의 난황유를 얻을 수 있는 것으로 판단되었다.판단되었다.