Effect of Initial Fermentation Degree of Soybean Pastes on the Physicochemical Properties of Lactobacillus plantarum-Inoculated Soybean Pastes

Dayeon Ryu,Ki-Hyo Jang,Jeonghee Surh 한국식품영양과학회 2013 한국식품영양과학회 학술대회발표집 Vol.2013 No.11

Determination of Ethyl Carbamate in Alcoholic Beverages and Fermented Foods Sold in Korea

Dayeon Ryu,Bogyoung Choi,Eunjoo Kim,Seri Park,Hwijin Paeng,Cho-il Kim,Jee-yeon Lee,Hae Jung Yoon,Eunmi Koh 한국독성학회 2015 Toxicological Research Vol.31 No.3

Ethyl carbamate (EC) classified as a probable human carcinogen (Group 2A) is naturally formed in alcoholic beverages and fermented foods during fermentation process and/or during storage. The objective of this study was to analyze EC in 34 food items including 14 alcoholic beverages and 20 fermented foods sold in Korea. Each food was collected from 18 supermarkets in 9 metropolitan cities in Korea, and then made into composite. According to food composition and alcohol content, samples were divided into four matrices such as apple juice, milk, Soju (liquor containing about 20% alcohol), and rice porridge. The maximum EC value of 151.06 μg/kg was found in Maesilju (liquor made from Maesil and Soju). Whisky and Bokbunjaju (Korean black raspberry wine) contained 9.90 μg/kg and 6.30 μg/kg, respectively. EC was not detected in other alcoholic beverages. Of 20 fermented foods, Japanese-style soy sauce had highest level of 15.59 μg/kg and traditional one contained 4.18 μg/kg. Soybean paste had 1.18 μg/kg, however, EC was not found in other fermented foods.

In Vitro Digestion Stability of the Oxidation Products Generated from Thermally Oxidized Linolenic Acid in the Presence of Casein Protein

Dayeon Ryu,Jeonghee Surh 한국식품영양과학회 2012 한국식품영양과학회 학술대회발표집 Vol.2012 No.10

Determination of Ethyl Carbamate in Alcoholic Beverages and Fermented Foods Sold in Korea

Ryu, Dayeon,Choi, Bogyoung,Kim, Eunjoo,Park, Seri,Paeng, Hwijin,Kim, Cho-il,Lee, Jee-yeon,Yoon, Hae Jung,Koh, Eunmi Korean Society of ToxicologyKorea Environmental Mu 2015 Toxicological Research Vol.31 No.3

Ethyl carbamate (EC) classified as a probable human carcinogen (Group 2A) is naturally formed in alcoholic beverages and fermented foods during fermentation process and/or during storage. The objective of this study was to analyze EC in 34 food items including 14 alcoholic beverages and 20 fermented foods sold in Korea. Each food was collected from 18 supermarkets in 9 metropolitan cities in Korea, and then made into composite. According to food composition and alcohol content, samples were divided into four matrices such as apple juice, milk, Soju (liquor containing about 20% alcohol), and rice porridge. The maximum EC value of $151.06{\mu}g/kg$ was found in Maesilju (liquor made from Maesil and Soju). Whisky and Bokbunjaju (Korean black raspberry wine) contained $9.90{\mu}g/kg$ and $6.30{\mu}g/kg$, respectively. EC was not detected in other alcoholic beverages. Of 20 fermented foods, Japanese-style soy sauce had highest level of $15.59{\mu}g/kg$ and traditional one contained $4.18{\mu}g/kg$. Soybean paste had $1.18{\mu}g/kg$, however, EC was not found in other fermented foods.

Application of response surface methodology to acidified water extraction of black soybeans for improving anthocyanin content, total phenols content and antioxidant activity

Ryu, Dayeon,Koh, Eunmi Elsevier 2018 Food chemistry Vol.261 No.-

<P><B>Abstract</B></P> <P>Acidified water extraction of total anthocyanin content, total phenol content and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity from black soybeans (<I>Glycine</I> max [L.] Merr. Cheongja4ho) was optimized using response surface methodology (RSM). A five-level, three-factor central composite design was employed to optimize the conditions for the maximum yields of these three components using19 different experiments. The HCl concentration (0.3–0.5%), solid-liquid ratio (1/30–1/50 g/mL) and extraction temperature (30–50 °C) significantly affected three components. The optimized conditions were HCl concentration of 0.359%, solid-liquid ratio of 1/54.2 g/mL and extraction temperature of 56.8 °C for total anthocyanin content (136.68 mg/100 g), total phenol content (1197.09 mg/100 g) and ABTS<SUP> +</SUP> scavenging activity (211.65 mg/100 g). These experimental values fit well with the predicted values. Among three anthocyanins found in the black soybean extracts, cyanidin-3-<I>O</I>-glucoside was the major one (65–73% of the total), followed by petunidin-3-<I>O</I>-glucoside (17–23%) and delphinidin-3-<I>O</I>-glucoside (10–12%).</P> <P><B>Highlights</B></P> <P> <UL> <LI> The conditions for the maximum yield of anthocyanins from black soybeans were optimized. </LI> <LI> A five-level, three-factor central composite design was employed. </LI> <LI> HCl concentration, solid-liquid ratio and extraction temperature affected the yields. </LI> <LI> The differences between the predicted and experimental values were <3%. </LI> <LI> These results confirm the validity and adequacy of the predicted model. </LI> </UL> </P>

Influences of Co-incubated Native or Denatured Proteins on the In Vitro Digestion Stability of Linolenic Acid-Induced Oxidation Products

Dayeon Ryu,Jeonghee Surh 한국식품영양과학회 2012 한국식품영양과학회 학술대회발표집 Vol.2012 No.10

한국인의 안토시아닌 섭취량과 주요 급원식품

류다연(Dayeon Ryu),고은미(Eunmi Koh) 동아시아식생활학회 2017 동아시아식생활학회지 Vol.27 No.4

매실주의 에틸카바메이트 분석

류다연(Dayeon Ryu),고은미(Eunmi Koh) 동아시아식생활학회 2015 동아시아식생활학회지 Vol.25 No.2

숙성기간이 다른 강원도 재래식 된장의 품질 특성 및 산화 안정성

류다연(Dayeon Ryu),서정희(Jeonghee Surh) 한국식품영양과학회 2021 한국식품영양과학회지 Vol.50 No.1

본 연구에서는 프리미엄 된장에 대한 소비자 요구를 겨냥하여 전통방식으로 소규모 제조된 강원도 재래식 된장의 품질특성을 숙성기간에 따라 평가함으로써 상품화 가능성을 탐색하였다. 숙성기간이 긴 된장일수록 탄수화물, 단백질, 조회분 등 주요 일반성분과 총 아미노산 함량이 높았으며, 글루탐산 함량의 감소 없이 GABA가 유의적으로 증가한 특성을 보였다. 이는 수분감소로 된장이 농축된 결과로 해석되었다. 미생물이 지닌 가수분해효소 작용으로 2년 정도 숙성된 판매 시점의 재래식 된장은 숙성 초기와 비교해 식이섬유는 유의적으로 낮았고 유리아미노산 비율, 가용성 고형분, 적정산도는 높았다. 특히 7년 정도 숙성된 된장에서는 산도가 다소 감소하는 경향이 관찰되었는데, 이는 축적된 유기산이 유산균 증식을 feedback 제어했거나 알코올 발효의 기질로 사용되었기 때문으로 해석하였다. 된장 숙성 초기에 증가했던 페놀 함량은 1년 이상 숙성기간이 길어지면 일정하게 유지되는 경향을 나타내었다. 이 현상은 된장 속 이소플라본 배당체 대부분이 숙성 1년 이내에 비배당체로 전환되었기때문으로 해석되었다. 한편 숙성기간이 증가할수록 된장 속 입자들은 동일한 크기 범위 내에서 넓은 단봉분포에서 좁은 다봉분포로 변해 숙성과 함께 물질의 저분자화가 일어남을 시사해주었다. 미생물에 의한 물질 분해가 충분치 않았던 숙성 초기 된장은 높은 수분함량에도 경도가 높았으며, 상대적으로 물질 분해가 충분히 진행된 숙성 후기 된장은 수분감소로 단단한 특성을 나타내었다. 이 결과는 숙성시기에 따라 된장 경도에 영향을 미치는 주요인이 다를 수 있음을 시사하였다. 숙성기간이 다른 강원도 재래식 된장의 이화학적 특성들은 상업용 된장의 품질 지표 범위와 대부분 유사하였으나 산화 안정성에서는 유의적으로 뚜렷한 차이를 나타내었다. 산화 유도시스템 하에서 재래식 된장은 숙성기간과 관계없이 상업용 된장보다 많은 양의 지방산화물질(MDA)을 생성함으로써 낮은 산화 안정성을 보여주었다. 이는 재래식 된장의 원료가 콩, 소금, 물로 상업용 된장의 원료조성보다 상대적으로 단순하였기 때문으로 해석하였다. 이 결과는 전통재래식 된장의 상품화 과정에서 숙성에 따른 된장의 이화학적 특성 및 산화 안정성에 관한 과학적 자료가 반영되어야 할 필요성을 시사해주었다. Traditional doenjang fermented for periods ranging from 4 months to 7.3 years were collected from a local supplier in Gangwon province. Doenjang were analyzed for physicochemical properties and oxidative stability depending on the fermentation time, to include them as specialty products. Doenjang when fermented for a longer time tended to have higher content of carbohydrates, protein, crude ash, total amino acids and γ-aminobutyric acid. The proportions of free amino acids and soluble solids were also found to be higher, while the dietary fiber content was lower. In addition, particle size distribution turned multimodal from monomodal in the same size range. This could be attributed to the increasing enzymatic breakdown of macromolecules by microorganisms in the doenjang. The hardness of doenjang appeared to decrease for the same reason. Total phenol content that increased at the beginning of fermentation remained the same after 1 year of fermentation, indicating that most of the isoflavone glycosides had been converted to aglycone. Under an oxidation accelerating system, the traditional doenjang generated appreciably higher amounts of malondialdehyde compared with the commercial products, indicating lower oxidative stability. These results could be used as a scientific basis for setting fermentation time and storage conditions for the successful development of specialty doenjang.

반응표면분석법을 이용한 캠벨얼리 포도의 총 안토시아닌과 총 페놀의 초음파 추출조건 최적화

류다연(Dayeon Ryu),고은미(Eunmi Koh) 한국식품과학회 2018 한국식품과학회지 Vol.50 No.5

포도의 안토사이아닌과 페놀 화합물의 고효율 추출을 위해 초음파 추출방법을 이용하여 반응표면분석법으로 조건을 최적화하였다. Box-Behnken design을 사용하여 시료-용매 비율, 추출시간, 초음파의 진폭을 독립변수로 하였으며, 총 안토사이아닌과 총 페놀 함량을 최대로 하는 추출조건을 최적화하였다. 총 안토사이아닌 함량은 3가지 독립변수가 유의적인 요인으로 시료-용매 비율이 증가할수록, 추출시간과 진폭은 감소할수록 총 안토사이아닌 함량이 증가하는 경향을 보였으나, 총 페놀 함량은 3가지 독립변수 모두 유의적인 요인이 아닌 것으로 나타났다. 총 안토사이아닌과 총 페놀 함량의 예측 값과 실측 값이 유사하여 본 연구에서 예측된 회귀식을 신뢰할 수 있음을 보여주었다. In this study, ultrasound-assisted extraction conditions of total anthocyanins and total phenolic compounds from Campbell early grape (Vitis labruscana) were optimized via response surface methodology using a Box-Behnken design. Three independent variables, including solid-liquid ratio (1/30-1/50 g/mL), extraction time (2-10 min), and amplitude (20-100%), significantly affected total anthocyanin content. However, no significant effect of these variables was observed in the total phenolic compound content. The optimized extraction conditions were solid-liquid ratio of 1/48.13 g/mL, extraction time of 2 min, and amplitude of 20%. Under these conditions, the predicted values of total anthocyanins and total phenolic compounds were 94.96 and 1,661.16 mg/100 g dry weight (DW), respectively. The experimental values of total anthocyanins and total phenolic compounds were 88.25 and 1,554.37 mg/100 g DW, respectively, which is well matched with the predicted values within 7.5% difference.