시판 고산도 식초의 이화학적 품질 및 항산화 특성

조덕조(Deokjo Jo),박은주(Eun-Joo Park),여수환(Soo-Hwan Yeo),정용진(Yong-Jin Jeong),권중호(Joong-Ho Kwon) 한국식품영양과학회 2013 한국식품영양과학회지 Vol.42 No.8

총 산도 10% 이상의 시판 고산도 식초를 원료(사과농축액, 맥아엑기스, 액상포도당 및 현미당화농축액)와 산도(2배 및 3배)에 따라 구입하여 이화학적 품질 및 항산화 특성을 확인하였다. 총산 함량은 2배 식초(12.10~13.41%)와 3배 식초(18.15~18.36%) 사이 유의적인 차이를 나타내었고, 식초의 당도 및 환원당 함량은 각각 7.00~10.80°Brix 및 1.32~3,885.90 mg% 범위로 확인되었으며 일정한 경향은 관찰되지 않았다. 고산도 식초의 유리당으로 fructose 및 glucose가 주로 확인되었고, 2배 식초의 경우 3배 식초에 비해 종류와 함량 측면에서 비교적 우수한 것으로 분석되었다. 식초의 품질지표인 acetic acid는 모든 식초에서 7,171~14,762 mg% 함량으로 분석되었고, oxalic acid의 경우 시판 고산도 식초에서는 확인할 수 없었다. 맥아엑기스를 사용 Various commercial vinegars of high-strength acidity (10% or more of total acidity) were investigated to compare their physicochemical and antioxidant properties. The total acidity of double-strength vinegars was relatively lower than triple-strength vinegars. Irrespective of the acidity, sugar and reducing sugar content ranged from 7.00~10.80°Bx and 1.32~3,885.90 mg%, respectively. Free sugars were mainly composed of fructose and glucose, and were relatively high in double-strength vinegars. The content of acetic acid (a principal organic acid in vinegars) increased with acidity, but oxalic acid was not identified in commercial high-strength acidity vinegars. Double-strength vinegars using malt extracts were the highest in free amino acid content, showing 24 kinds of amino acids. The content of total phenolics and flavonoids was highest in apple vinegars of double-strength acidity, which affected the scavenging ability of DPPH and ABTS radicals. Overall, the quality of high-strength acidity vinegars was affected by its content and production methods, and double-strength acidity vinegar using apples showed the best antioxidant activities.

포도과즙을 이용하여 제조한 고산도 식초의 품질특성

우승미,여수환,권중호,김선화,정용진 한국식품저장유통학회 2015 한국식품저장유통학회지 Vol.22 No.1

This study was conducted to develop a high-acidity vinegar production (over TA 10%) technology using grape juice to reduce the importation of high-acidity vinegar. The manufacturing condition’s effect on the quality of high-acidity vinegar using pure grape juice without the addition of other nutrients for fermentation was investigated. Twelve percent acidity in vinegar was obtained from grape wine with 6% alcohol content. The acetic-acid yield from grape wine decreased when the wine’s initial alcohol content was high, which extended the induction time. The pH value was similar in all the treatment groups. The sugar content of the 1st-stage fermentation (1st AAF) was proportional to the initial alcohol content whereas in the 2nd-stage fermentation (2nd AAF), the sugar content was highest in the 6%-alcohol treatment. The major organic acids of the high-acidity grape vinegar included tartaric acid, malic acid, and citric acid. The acid content of the high-acidity initial alcohol group was higher than that of the low-acidity initial alcohol group due to the alcohol content added by the fed-batch and acetic-acid yield difference. The ethyl alcohol content was 364~6,091 ppm (the main alcohol while the others had only traces in all the groups). In conclusion, it was possible to manufacture 12% high-acidity vinegar without the addition of an external nutrient source to grape wine containing 6% initial alcohol content. Finally, a complementary study will be required to shorten the fermentation period through the fed-batch-style addition of alcohol for the purpose of industrialization.

1P-364 Effect of acidity of zeolite catalysts in esterification of oleic acid dissolved in soybean oil

정상민,이원준,정경환,이헌,정상철 한국공업화학회 2017 한국공업화학회 연구논문 초록집 Vol.2017 No.1

Effect of acidity of zeolite catalysts was evaluated in esterification of oleic acid dissolved in soybean oil. The catalytic activity of zeolites was studied in the esterification of oleic acid with methanol in soybean oil. The influences of acidity and pore structure of the zeolites were investigated in relation to conversion of the oleic acid on the zeolite catalysts. H+ ion exchanged ZSM-5 (HMFI) and mordenite (HMOR) zeolites conducted with different Si/Al ratio were employed to examine an influence of acidity in the reaction. Conversion of oleic acid was about 80% on HMOR zeolites and HMFI(25) zeolite. The conversion of oleic acid was improved as the amount of acid site increased. The amount of acid site of the zeolites affected significantly the catalytic activity in the esterification of oleic acid.

동결농축법을 이용한 고산도 복분자 농축식초 제조에 관한 연구

성지연,이익희 한국융합학회 2021 한국융합학회논문지 Vol.12 No.11

최근까지 고산도 식초 제조를 위한 다양한 연구가 진행되어 왔으나 식초의 농축공정에 대한 연구는 거의 없었다. 본 연구에서는 고품질의 고산도 식초 제조를 위해 동결농축법의 도입 가능성을 알아보았다. 총산도가 서로 다른 3종류 (7.53, 5.43, 및 3.72)의 복분자 발효식초를 동결 및 융해시켜 얻은 동결농축식초분획을 대상으로 총산도, 산도pH, 비중 및 포도당 농도를 측정하였다. 총산도, 비중 및 포도당 농도 모두 최초식초의 15%가 융해되었을 때 가장 높은 것으로 나타났다. 산도pH는 최초식초의 15%가 융해되었을 때 가장 낮은 것으로 나타났다. 누적산도 측정결과 최초식초의 20% 가 융해되었을 때 9.32로 가장 높았는데 이는 최초식초보다 3.89높은 수치였다. 본 연구에서는 동결농축법을 이용하여 식초를 효과적으로 농축할 수 있을 뿐 만 아니라 융해비율 조정으로 원하는 총산도의 식초를 효과적으로 얻을 수 있음을 확인하였다. 그러나 고산도 농축식초 제조공정에 동결농축법의 도입여부를 판단하기 위해서는 유기산 및 아미노산 분석 등의 연구가 필요할 것으로 사료된다. Until recently, various studies for the production of high-acidity vinegar have been conducted, but there have been few studies on the concentration process of vinegar. In this study, the possibility of introducing freeze-concentration method was investigated for the production of high-quality, high-acidity vinegar. Acidity, pH, specific gravity, and glucose concentration were measured for frozen concentrated vinegar fractions obtained by freezing and thawing three types of Rubus coreanus vinegar with different acidy (7.53, 5.43, and 3.72). Acidity, specific gravity, and glucose concentration were all highest when 15% of the original vinegar was thawed. pH was the lowest when 15% of the original vinegar was melted. As a result of the measurement of cumulative acidity, when 20% of the original vinegar was melted, it was the highest at 9.32, which was 3.89 higher than that of the original vinegar. In this study, it was confirmed that vinegar can be effectively concentrated using the freeze concentration method and at the same time, the thawing ratio can be controlled to effectively obtain vinegar with the desired acidity. However, it is considered that studies such as organic acid and amino acid analysis are needed to determine whether the freeze-concentration method is introduced into the high-acidity concentrated vinegar manufacturing process.

무 쥬스 제조를 위한 starter로써 동치미에서 분리한 유산균의 동정 및 발효 특성

김정희,김종일,Kim, Jung-Hee,Kim, Jong-Il 한국미생물학회 1999 미생물학회지 Vol.35 No.4

본 연구는 동치미에서 유산균을 분리하여 동치미의 가능성이 강화된 무 주스를 제조하기 위한 starter로써의 가능성을 검토하기 위하여 유산균의 발효특성을 조사하였다. 동치미에서 분리 동정된 40 균주는 당 발효능과 양상에 따라 5개의 group으로 분류되었다. Species별 분포를 살펴본 결과는 Leuconostoc mesenteroides, Lactobacillus brevis, Lactobacillus sake, Lactobacillus plantarum, Lactobacillus fermentum의 5개 균종이었으며, 유산균의 분포는 Leuconostoc mesenteroides가 52.5%로 최 우점종으로 나타났다. 분리된 5개의 group에서 가장 생육능이 왕성한 1개 균주씩 Leuconostoc mesenteroides J-9, Lactobacillus brevis J-12, Lactobacillus plantarum J-39, Lactobacillus fermentum J-7 등 5균주를 선정하여 한외 여과한 무즙에 각각 0.3($10^6$ cfu/㎖)%씩 접종하여 25${\circ}C$에서 9일간 숙성하면서 pH 및 총 산도, 비휘발성유기산함량의 변화 등을 조사하였다. 각 접종 균주 중 Lactobacilus plantarum의 생육능이 가장 빠르게 나타났으며 Lactobacillus sake가 가장 느리게 성장하였다. 발효 개시 전의 한외 여과한 무즙의 pH 및 총 산도는 6.30~6.36, 0.09~1.0%이었으나 9일째 pH 3.2~4.3, 0.85~1.2%로 나타났다. 각 접종 균주의 pH, 산도의 변화를 비교해보면 미생물의 생육능과 상관성이 높아 유산균수의 증가속도가 빠를수록 pH는 빠르게 감소하고, 산도는 빠르게 증가하였다. 비휘발성 유기산의 변화를 보면 모든 접종구에서 시트르산, 말산, 말론산, 숙신산은 감소하는 경향으로 나타났으며 락트산은 발효가 진행됨에 따라 증가하였다. 관능적으로 맛에 좋은 영향을 주는 유기산으로 알려진 숙신산과 락트산의 함량을 보면 L. mesenteroides J-9가 가장 높게 나타났다. 락트산 단독의 경우는 L. plantarum J-39m, L. brevis J-12 접종구의 순으로 높게 나타났다. 이 ${\cdot}$ 화학적 검사와 향미에 대한 관능검사결과 L. mesenteroides J-9, L. brevis J-12, L. fermentum J-7이 무쥬스의 젖산발효를 위한 starter로써 적합한 것으로 나타났다. This study was aimed at the investigation of the possibility of the addition of lactic acid bacteria as "starter"for the preparation of radish juice. Forty strains of lactic acid bacteria were isolated from dongchimi that was fermented by a traditional method. The isolates were assorted into 5groups, Leuconostoc mesenteroides subsp. mesenteroides (J-9), Lacobacillus brevis (J-12), Lactobacillus fermentum (J-7), Lactobacillus sake (J-20), and Lactobacillus plantarum (J-39). Leuconostoc mesenteroides was predominated in the sample of dongchimi with frequency of 52.5%. Each of the strain, which exhibited the beat growth in the species, was selected in the 5species, and investigation of the fermentation characteristcis was carried out. The fermentation were performed for 9 days at 25${\circ}C$ after the inoculation of 0.3% ($10^{6}$ cfu/㎖) to each ultra-filtrated radish juice. The pH, total acidity, content of non-volatile organic acids were examined during the fermentation period. Lactobacillus plantarum showed the highest growth rate and the growth rate of Lactobacillus sake was the lowest. The pH (6.3-6.36) and total acidity (0.09-1.0 %) fo the ultrafiltrated radish juice before fermentation were changed to 3.2-4.3 and 0.65-1.2% after 9days, respectively. The changes of the pH and total acidity were related with the growth of the lactic acid bacteria; the better growth of lactic acid bacteria, the more rapid decrease of pH and increase of the total acidity. when the amount of non-volatile organic acids were estimated during fermentation, citric acid, malic acid, malonic acid, and succinic acid were decreased in all cases. However, the content of lactic acid increased with the progression of fermentation. L. mesenteroides (J-9), L. brevis (J-12) and L. fermentum (J-7) were chosen for the candidates of the starter for the lactic fermentation of radish juice based on the biochemical analysis and sensory evaluation.

Dehydration of glycerin to acrolein over H₃PW₁₂O₄₀ heteropolyacid catalyst supported on silica-alumina

Kang, Tae Hun,Choi, Jung Ho,Bang, Yongju,Yoo, Jaekyeong,Song, Ji Hwan,Joe, Wangrae,Choi, Jun Seon,Song, In Kyu Elsevier 2015 Journal of molecular catalysis Chemical Vol.396 No.-

<P><B>Abstract</B></P> <P>A series of tungstophosphoricacid (H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>) catalysts supported on silica-alumina (SA-X (<I>X</I> =0, 15, 30, 50, 70, 85, and 100)) with different SiO<SUB>2</SUB> content (<I>X</I>, mol%) were prepared, and they (H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-X) were applied to the gas-phase dehydration of glycerin to acrolein. The effect of support composition on the physicochemical properties and catalytic activities of H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-X catalysts was investigated. Total acidity and Brønsted acidity of H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-X catalysts determined from pyridine-adsorbed in situ FT-IR spectroscopy measurements showed volcano-shaped trends with respect to SiO<SUB>2</SUB> content. Among the catalysts, H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-50 exhibited the largest total acidity while H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-85 showed the largest Brønsted acidity. The results of <SUP>27</SUP>Al NMR spectroscopy analyses of H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-X (<I>X</I> =15, 30, 50, 70, and 85) catalysts clearly demonstrated that Brønsted acidity of the catalysts was proportional to the amount of Al<SUP>IV</SUP> species. It was revealed that yield for acrolein increased with increasing Brønsted acidity rather than total acidity of H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-X catalysts. Among the catalysts tested, H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-85 with the largest Brønsted acidity showed the highest yield for acrolein. A synergistic effect between H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB> and SA-85 for H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-85 catalyst was also observed in the dehydration of glycerin to acrolein. Moreover, the catalytic performance of regenerated H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-85 catalyst was almost recovered compared to that of fresh H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SA-85 catalyst.</P> <P><B>Highlights</B></P> <P> <UL> <LI> H<SUB>3</SUB>PW<SUB>12</SUB>O<SUB>40</SUB>/SiO<SUB>2</SUB>-Al<SUB>2</SUB>O<SUB>3</SUB> (SA-X) catalysts with different SiO<SUB>2</SUB> content (<I>X</I>) were prepared. </LI> <LI> Gas-phase dehydration of glycerin to acrolein was conducted. </LI> <LI> Brønsted acidity of the catalysts played an important role in the reaction. </LI> <LI> Yield for acrolein increased with increasing Brønsted acidity of the catalysts. </LI> </UL> </P>

Grafting Effects on Root Activity and Amino Acid Contents in Bleeding Sap of Muskmelon

Tianlai Li,Yifei Liu,Hongyan Qi,Chunming Bai 한국원예학회 2009 Horticulture, Environment, and Biotechnology Vol.50 No.3

The grafting effects on the yield and quality of muskmelon fruits were studied based on the measurements of root activity, acidity, electric conductivity and amino acids of bleeding sap. The results revealed that grafting enhanced significantly the activities of root systems and increased the volume and electric conductivity of bleeding sap in muskmelon during growth period. The fruit yield of grafted plants increased by 9.12%. The amino acids in bleeding sap of self-rooted and grafted muskmelon mainly consisted of threonine and glutamic acid. Grafting decreased significantly the contents of threonine, glutamic acid, cysteine, lysine and NH₃ in bleeding sap in the early and late growth stages, but increased the contents of aspartic acid, threonine, serine, glutamic acid, alanine, valine, isoleucine, leucine, tyrosine, phenylalanine, lysine, histidine and arginine in the middle growth stage. In the late growth stage, the contents of threonine, glutamic acid, cysteine, lysine and arginine in bleeding sap of grafted plants were reduced by 44.88%, 52.45%, 41.67%, 58.62% and 62.61%, respectively. The total amino acid content of self-rooted and grafted muskmelon plants showed the same trend of high-low-high in the whole growth period. In the early and late growth stages, the total amino acid content of self-rooted plants was significantly higher than that of the grafted plants. The increment of total amino acid in self-rooted muskmelon from middle to late growth stage was also greater than that in grafted muskmelon. It is suggested that the nutritional quality of grafted muskmelon fruits might be due to the changes of amino acid supply in bleeding sap.

Isolation of an Acetic Acid Bacterium Acetobacter pasteurianus CK-1 and Its Fermentation Characteristics

방규호,김채원,김철호 한국생명과학회 2022 생명과학회지 Vol.32 No.2

막걸리 식초 생산에 효과적인 초산균을 분리하기 위해 다양한 시료에서 초산균을 검색하였고, 그 중 초산 생산이 우수한 균주인 Acetobacter pasteurianus CK-1을 최종 분리하였다. 분리균주의 최적 생육온도는 30.0℃로 확인되었고, pH 6.0에서 가장 왕성하게 생장하였으며, pH 5.5~6.5 범위에서 잘 생장하였다. A. pasteurianus CK-1은 배지의 초기 에탄올 농도가 4%일 때 가장 왕성하게 생장하였고, 7%의 에탄올 농도에서도 생장이 가능하였다. 분리균주를 막걸리에 접종하여 초산 발효를 유도하였을 때, 발효 초기 pH 3.54였던 것이 발효가 진행되면서 점차 낮아져서 발효 18일 후에는 pH 2.77이 되었다. 산도는 발효 초기에 0.75%였던 것이 발효 4일경부터 점차 증가하여 최종 산도는 5.54%로 증가하였다. A. pasteurianus CK-1 발효 식초에서는 acetic acid가 3,575.7±48.6 mg%로 높게 검출되었고, malic acid와 citric acid는 각각 2,150.8±27.6 mg%와 55.8±3.7 mg%로 검출되었다. 접종한 균주의 종류에 따라 생성되는 유기산의 함량과 비율이 유의하게 차이가 나는 것을 확인하였다. 초산 발효 동안 발효액 내의 효모와 A. pasteurianus CK-1의 개체군은 반비례적으로 변화하였다. 발효 초기에는 효모가 우점하였으나, 발효가 진행됨에 따라 A. pasteurianus CK-1이 서서히 증식하여 10일 후에는 정체기에 이르렀다. To effectively isolate acetic acid bacteria for producing makgeolli vinegar, various products were researched, and Acetobacter pasteurianus CK-1, a strain that is excellent in acetic acid production, was finally isolated. The optimal growth temperature of the isolated strain was confirmed to be 30℃, and it grew well in the pH range of 5.5~6.5, with optimal growth at pH 6. A. pasteurianus CK-1 had the most active proliferation when the initial ethanol concentration in the medium was 4%, and growth was possible even at an ethanol concentration of 7%. When inoculating the isolated strain into makgeolli to induce acetic acid fermentation, the pH at the beginning of fermentation was 3.54, which was gradually lowered to 2.77 after 18 days of fermentation. The acidity was 0.75% at the beginning of fermentation and gradually started to increase from the 4th day of fermentation. The final acidity at the end of fermentation was 5.54%. In the vinegar fermented by inoculating A. pasteurianus CK-1, acetic acid content was detected to be as high as 3,575.7±48.6 mg%, and the malic acid and citric acid contents were 2,150.8±27.6 and 55.8±3.7 mg%, respectively. Further, it was confirmed that the content and ratio of the organic acids produced significantly differed depending on the type of inoculated bacterial strain. During acetic acid fermentation, the populations of yeast and A. pasteurianus CK-1 were inversely changed. In the initial stage of fermentation, yeast dominated, and after 10 days of fermentation, A. pasteurianus CK-1 slowly proliferated and reached stationary phase.

전처리과정과 분석방법에 따른 막걸리의 총산 함량 비교

김예슬(Ye Seul Kim),신광섭(Kwang Seup Shin),이정희(Jeung Hee Lee) 한국식품영양과학회 2017 한국식품영양과학회지 Vol.46 No.5

막걸리의 총산 함량은 함유된 부유물과 발효과정에서 발생한 탄산가스의 제거 여부 및 분석방법들에 의해 영향을 받는다. 시중 유통되는 막걸리를 여과하여 부유물을 제거하고 magnetic bar로 stirring 하여 탄산가스를 제거한 후 총산을 분석한 결과 살균막걸리(4종)의 여과 전 0.379~0.477% 총산이 여과 후 0.167~0.225%로, 탄산 제거 후에는 0.132~0.170%로 유의적으로 감소하였고(P<0.05), 생막걸리(5종)는 여과 전 0.412~0.467%의 총산이 여과 후에는 0.157~0.365%로(P<0.05), 탄산 제거 후에는 0.143~0.280%로 유의적으로 감소하였다(P<0.05). 총산 분석방법을 비교한 결과 BTB+NR 지시약을 사용한 경우 살균막걸리와 생막걸리의 총산 함량은 각각 0.105~0.123%와 0.105~0.200%로써 막걸리의 총산 기준 규격인 0.5(acetic acid%) 이하로 분석되었다. 반면 AOAC 분석법인 phenolphthalein 용액으로 적정한 경우 살균막걸리와 생막걸리의 총산 함량은 각각 0.129~0.154%와 0.130~0.255%였고, pH 8.2를 적정점으로 한 경우 0.137~0.162%와 0.140~0.279%로 나타나 총산 함량이 높게 나타났다. BTB 용액으로 적정한 경우 BTB+NR 지시약을 사용한 경우보다는 높고 AOAC법보다는 낮은 것으로 확인되었다. 막걸리에 함유된 유기산은 oxalic acid, malic acid, citric acid, lactic acid, acetic acid+succinic acid였으며, malic acid는 H와 I를 제외한 모든 막걸리에서 0.030~0.134 mg/mL, acetic acid+succinic acid는 0.056~0.372 mg/mL, lactic acid는 0.127~0.776 mg/mL로 살균막걸리보다 생막걸리에 비교적 많이 함유되었고, citric acid는 ND~1.159 mg/mL로 분석되었다. The total acidity (TA) of Makgeolli was affected by suspended solids and CO2 produced during the fermentation process. Nine Makgeollis (four sterilized and five unsterilized Makgeollis) were collected in the market, and their TAs were compared before and after filtration and CO2 removal. TAs of sterilized Makgeollis were 0.379∼0.477%, which significantly decreased to 0.167∼0.225% after filtration and 0.132∼0.170% after CO2 removal (P<0.05). TAs of unsterilized Makgeollis were 0.412∼0.467% and decreased to 0.157∼0.365% after filtration and 0.143∼0.280% after CO2 removal (P<0.05). TAs of Makgeollis were compared by three methods using different indicators. The TAs of sterilized and unsterilized Makgeollis were 0.105∼0.123% and 0.105∼0.200%, respectively, by bromthymol blue+neutral red (light green), 0.129∼0.154% and 0.130∼0.255%, respectively, by phenolphthalein (faint pink), and 0.120∼0.146% and 0.130∼0.232%, respectively, by bromthymol (blue). Nowadays, Makgeolli is commercialized with various distinct colors, and thus it is important to select appropriate indicators for proper titration endpoint identification for TA measurement. The compositions of organic acids profiles varied depending on sterilized or unsterilized Makgeollis, in which oxalic acid (0.108∼0.329 mg/mL), malic acid (ND to 0.134 mg/mL), lactic acid (0.127∼0.776 mg/mL), and citric acid (ND to 1.159 mg/mL) were found, and lactic acid was in unsterilized more than sterilized Makgeollis.

Esterification of oleic acid in soybean oil on zeolite catalysts with different acidity

Kyong-Hwan Chung,Byung-Geon Park 한국공업화학회 2009 Journal of Industrial and Engineering Chemistry Vol.15 No.3

The catalytic activity of zeolites was studied in the esterification of oleic acid with methanol in soybean oil. The influences of acidity and pore structure of the zeolites were investigated in relation to conversion of the oleic acid on the zeolite catalysts. H+ ion exchanged ZSM-5 (HMFI) and mordenite (HMOR) zeolites conducted with different Si/Al ratio were employed to examine an influence of acidity in the reaction. Conversion of oleic acid was about 80% on HMOR zeolites and HMFI(25) zeolite. The conversion of oleic acid was improved as the amount of acid site increased. The amount of acid site of the zeolites affected significantly the catalytic activity in the esterification of oleic acid.