Optimization of the saccharification conditions for the production of sweet potato Jocheong(syrup) and identification of unpleasant odor generated during saccharification 고구마 조청 제조를 위한 당화조건 확립 및 당화과정에서 생성되는 불쾌취 원인 물질 규명
이희원 Hee Won Lee , 백충훈 Chung Hun Baek , 마상용 Sang Yong Ma , 정미남 Mi-nam Chung , 정문웅 Mun Yhung Jung
Optimization of the saccharification conditions for the production of sweet potato Jocheong(syrup) and identification of unpleasant odor generated during saccharification 고구마 조청 제조를 위한 당화조건 확립 및 당화과정에서 생성되는 불쾌취 원인 물질 규명
이희원 Hee Won Lee , 백충훈 Chung Hun Baek , 마상용 Sang Yong Ma , 정미남 Mi-nam Chung , 정문웅 Mun Yhung Jung
DOI:10.9724/kfcs.2023.39.1.1
Abstract
Purpose: Jocheong (syrup) is traditionally prepared by saccharifying starch sources (commonly rice) with barley malt, followed concentrating by boiling. Methods: In this study, the saccharification conditions (time, temperature, addition of malt) of sweet potato paste were examined by analyzing the free sugars in the saccharified solution during saccharification (every 2 hrs for 10 hrs). Results: Free sugar contents in saccharified solutions were found to be dependent on malt addition, temperature, and time. It was also observed that a sour and unpleasant odor occurred after 6 hrs of the saccharification process. Through volatile compound analysis using HS-SPME-GC-MS, the main component of this unpleasant odor was positively identified as acetic acid. Considering both free sugar content and odor quality, the optimal saccharification condition was determined to be 60℃, 5 hrs, sweet potato paste 225 g, malt 15 g, and water 1 L. Saccharification was thereafter conducted in a pilot plant scale (20 L capacity tank) under the selected temperature and time conditions with sweet potato paste 2250 g, malt 150 g, and water 10 L. Moisture was evaporated by subjecting the saccharified solution to boiling, to obtain the Jocheong (total solid content of 76°Bx). Conclusion: The Jocheong syrup yield obtained from raw sweet potato was 26.8% (w/w), with total free sugar content of 44.5 g/100 g. The contents of fructose, glucose, sucrose, and maltose were determined to be 2.4, 3.2, 9.2 and 29.8 g/100 g, respectively, showing the exceptionally high proportion of sucrose as compared to the value reported in rice Jocheong. Our results clearly indicate that the free sugar profile obtained from sweet potato Jocheong differs greatly from the reported free sugar profile of rice Jocheong.
Antioxidant activities of 16 natural materials: Effect of the extraction solvent and analytical method applied during the measurement 추출용매와 항산화 활성 시험법에 따른 16종 천연 소재의 항산화 활성
이지예 Jiyea Lee , 손다연 Dayeon Son , 서정희 Jeonghee Surh
Antioxidant activities of 16 natural materials: Effect of the extraction solvent and analytical method applied during the measurement 추출용매와 항산화 활성 시험법에 따른 16종 천연 소재의 항산화 활성
이지예 Jiyea Lee , 손다연 Dayeon Son , 서정희 Jeonghee Surh
DOI:10.9724/kfcs.2023.39.1.14
Abstract
Purpose: This study investigates the effects of the extraction solvent and analytical method applied to determine the antioxidant activity of 16 natural food materials. Methods: Sixteen raw materials were extracted using solvents with different polarity index (PI): water (PI 9.0), ethanol (PI 5.1), and hexane (PI 0). The solvent extracts were measured for total reducing capacity (TRC), ABTS+ radical scavenging activity, and DPPH radical scavenging activity. All antioxidant data of the raw materials were subsequently characterized using Pearson’s correlation analysis and principal component analysis. Results: Except wheat flour, all materials showed higher TRC in the water and ethanol extracts compared to the hexane extracts. ABTS+ radical scavenging activity was also higher in water and ethanol extracts than the hexane extract. However, green tea and ginger showed the highest ABTS+ radical scavenging activity in hexane extracts. Pearson’s correlation analysis revealed that the analytical methods for TRC and ABTS+ radical scavenging activity correlated well in water (ρ=0.838, p<0.001) and hexane extracts (ρ=0.816, p<0.001), but not in the ethanol extract. DPPH radical scavenging activity was higher in the ethanol and hexane extracts compared to the water extract. Principal component analysis revealed that leek, green tea, and ginger possess distinctive characteristics as antioxidant raw materials. Conclusion: The results demonstrate that the antioxidant activity varies depending on the extraction solvents and analytical methods applied to measure the antioxidant activity, even for the same material. This study can be utilized for selecting natural antioxidant ingredients that successfully retard food oxidation.
Effect of various freezing and thawing methods on quality properties of passion fruit(Passiflora edulis) 냉동과 해동방법에 따른 백향과의 품질 특성
황영 Young Hwang , 박지현 Ji-hyun Park , 조용식 Yong-sik Cho , 김경미 Kyung-mi Kim , 장현욱 Hyun-wook Jang
DOI:10.9724/kfcs.2023.39.1.22
Abstract
Purpose: As tropical and subtropical fruit cultivation areas are increasing due to climate warming, this study evaluated the quality characteristics of each freezing and thawing method for passion fruit storage to find out how to minimize quality changes. Methods: As the freezing method, air cooled freezing, immersion freezing, and quick freezing were applied, and as the thawing method, room temperature thawing, running water thawing, and high pressure thawing method were applied. Drip loss, color, soluble solids, pH, acidity, hardness, and microbial properties after storage were evaluated. Results: The freezing speed was 0.05℃/min for air freezing, 0.47℃/min for immersion freezing, and 7.83℃/min for quick freezing and thawing in running water was faster than air cooled freezing after immersion or quick freezing. The drip loss was small in all thawing treatments of immersion freezing, and in quick freezing, except for high pressure thawing. Soluble solid content was highest in immersion freezing in room temperature thawing and air cooled freezing in running water thawing, and the lowest in quick freezing in case of high pressure thawing. Overall, the hardness decreased compared to the fresh fruit through freezing and thawing. When penetrating the peel, there was no significant difference between immersion freezing and quick freezing, and it was further decreased in air freezing. Conclusion: In conclusion, running water thawing after immersion freezing had the lowest drip loss and high soluble solids content, so it was advantageous for quality maintenance. And high pressure thawing after quick freezing, which is excellent for freezing speed and color maintenance, significantly affected the increase of drip loss due to outflow of nectar and the reduction of soluble solids, suggesting that it is not a suitable method for passion fruit storage.
Key Words
passion fruit, freezing, thawing, quality, drip loss
Characteristics of brownies prepared using rice bran protein 미강 단백질 첨가 브라우니의 특성 연구
백만희 Manhee Baek , 이경애 Kyong-ae Lee , 문세훈 Saehun Mun
Characteristics of brownies prepared using rice bran protein 미강 단백질 첨가 브라우니의 특성 연구
백만희 Manhee Baek , 이경애 Kyong-ae Lee , 문세훈 Saehun Mun
DOI:10.9724/kfcs.2023.39.1.34
Abstract
Purpose: Low-gluten brownies were prepared by partially replacing wheat flour with varying amounts of rice bran protein (RBP; 0, 10, 20, 30, and 40% (w/w)), and their characteristics were examined. Methods: The viscosity of the brownie batters was measured using a viscometer, the textural properties were evaluated using a texture analyzer, and Hunter color values were determined using a colorimeter. In addition, brownie appearances were evaluated visually. Results: Results of the viscosity measurement revealed that compared to the control group, the change in the brownie batter viscosity was minimal when RBP was added at 30% or less, but was significantly lower with 40% RBP addition. Increasing amounts of RBP resulted in decreased hardness, cohesiveness, and chewiness, but with no significant difference between samples, indicating that there was almost no change in texture with RBP supplementation. No differences were observed in the appearance of brownies, and no significant differences were obtained between samples in their L, a, and b values. Conclusion: Our results indicate that substituting wheat flour with less than 30% RBP, produces low-gluten and protein-enriched brownies without affecting the overall desired brownie qualities.
Quality characteristics and fresh noodle-making performance of commercial whole wheat flour milled from Korean domestic wheat with different particle sizes 입자크기가 다른 시판 국내산 통밀가루의 품질 특성 및 생면 제조 적성
김정언 Jeongeon Kim , 김형섭 Hyungseop Kim , 문유진 Yujin Moon , 이은정 Eun Jung Lee , 권미라 Meera Kweon
Quality characteristics and fresh noodle-making performance of commercial whole wheat flour milled from Korean domestic wheat with different particle sizes 입자크기가 다른 시판 국내산 통밀가루의 품질 특성 및 생면 제조 적성
김정언 Jeongeon Kim , 김형섭 Hyungseop Kim , 문유진 Yujin Moon , 이은정 Eun Jung Lee , 권미라 Meera Kweon
DOI:10.9724/kfcs.2023.39.1.41
Abstract
Purpose: This study aimed to assess the effect of particle size of commercial whole wheat flour milled from Korean domestic wheat on flour quality and fresh noodle-making performance. Methods: Whole wheat flours were analyzed for particle size, physiochemical properties, solvent retention capacity (SRC), sodium dodecyl sulfate (SDS) sedimentation volume, and pasting properties by rapid visco analyzer (RVA). The noodle-making performance of the flours was evaluated, and the total phenolic content and antioxidant activity of the whole wheat flours, and fresh and cooked noodles were measured. Additionally, the major flour quality parameters that influence the noodle-making performance were identified. Results: Two distinct groups (S and L group) of whole wheat flours based on ash content and particle size showed significant differences in all flour properties except for the protein content and pasting properties, and noodle quality parameters. The total phenol content and antioxidant activity of whole wheat flour and fresh and cooked noodles were not significantly different between both groups. Among the flour quality characteristics, ash, particle size, water SRC, sodium carbonate SRC, and SDS sedimentation volume correlated significantly with the noodle quality. Conclusion: Noodle-making performance of whole wheat flour is affected significantly by the ash content and particle size. Besides, water and sodium carbonate SRC and SDS sedimentation volume can be applied as useful quality parameters for the specification of whole wheat flour to produce noodles.
Changes in antioxidant and colon cancer cell growth inhibitory activities of Eragrostis tef extract according to cooking methods 조리방법에 따른 테프 추출물의 항산화 및 대장암세포 성장 억제 활성 변화
Changes in antioxidant and colon cancer cell growth inhibitory activities of Eragrostis tef extract according to cooking methods 조리방법에 따른 테프 추출물의 항산화 및 대장암세포 성장 억제 활성 변화
서진아 Jina Seo , 이중재 Jungjae Lee , 주지형 Jihyeung Ju
DOI:10.9724/kfcs.2023.39.1.53
Abstract
Purpose: The study aimed to investigate the changes in antioxidant and colon cancer cell growth-inhibitory activities of Eragrostis tef (ET) prepared using different cooking methods. Methods: Raw, steamed, baked, and roasted ET were freeze-dried and extracted with 80% ethanol (ETE). Total polyphenol content (TPC) and total flavonoid content (TFC), radical-scavenging activity (RSA) using 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2.2’-azino-bis(3-ethyl-benzthiazline-6-sulfonic acid) diammonium salt (ABTS), and ferric reducing antioxidant power (FRAP) of ETE were measured. Assays using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) were performed to determine the effect of ETE on the growth of HCT116 human colon cancer cells. Cell cycle analysis was also performed in HCT116 cells to assess the effect of ETE on cell cycle distribution. Results: TPC and TFC of raw ET were 0.87 mg gallic acid equivalent/g dry weight (DW) and 3.09 mg quercetin equivalent/g DW, respectively. DPPH RSA, ABTS RSA, and FRAP of raw ETE were 10.78-31.38% (at 375-1,500 μg/mL), 12.82% (at 1,500 μg/mL), and 23.71-71.80% (at 375-1,500 μg/mL), respectively. Steaming resulted in increased TPC and DPPH RSA but decreased TFC. Baking resulted in increased TPC, DPPH RSA, and FRAP. Roasting resulted in increased TPC, DPPH RSA, ABTS RSA and FRAP. Treatment of HCT116 cells with raw ETE at 100-1,000 μg/mL resulted in decreased growth (57.61-92.24% of control) along with G2/M arrest. Roasted ETE at 100-1,000 μg/mL resulted in further decreases in the growth of HCT116 cells, which was associated with both G2/M arrest and apoptosis induction. Conclusion: These results indicate that the antioxidant content and activities of ET are influenced by cooking methods and that roasting effectively enhances both the antioxidant and colon cancer cell growth-inhibitory activities in vitro.
Effects of heated onion peel extract on adipocyte differentiation and fat accumulated gene in 3T3-L1 cell 열처리한 양파껍질 추출물이 3T3-L1 지방세포 분화와 지방축적 관련 유전자 발현에 미치는 영향
Effects of heated onion peel extract on adipocyte differentiation and fat accumulated gene in 3T3-L1 cell 열처리한 양파껍질 추출물이 3T3-L1 지방세포 분화와 지방축적 관련 유전자 발현에 미치는 영향
김지은 Ji-eun Kim , 배지윤 Ji-yun Bae , 김미자 Mi-ja Kim
DOI:10.9724/kfcs.2023.39.1.65
Abstract
Purpose: This study was conducted to investigate the effect of onion peel extract heated at various temperatures on inhibition of fat accumulation during 3T3-L1 adipocyte differentiation. Methods: Onion peel were heated at 0(OPE), 140(140H-OPE), 170(170H-OPE), and 200(200H-OPE)℃ and extracted with 70% ethanol. Fat accumulation in 3T3-L1 adipocyte was observed by Oil red O staining. Expression of fat accumulation-related genes was analyzed by real-time PCR, and protein expression was determined using Western blot. Results: As a result of Oil red O staining in 3T3-L1 adipocyte, 50 μg/mL OPE, 140H-OPE, 170H-OPE, 200H-OPE treated group was significantly reduced by 21.77, 73.08, 79.00, and 79.66%, respectively, compared to adipocyte group(p<0.05). Moreover, 50 μg/mL 170H-OPE treatment of 3T3-L1 adipocyte significantly decreased the expression level of the adipogenic transcription factor gene including pparγ, c/ebpα, and srebp-1c by 55.94, 84.85, and 67.36% respectively. In addition, those of the level of lipogenic genes such as acc1, fas, scd1, ap2, and cd36 reduced significantly by 64.79, 72.95, 94.57, 53.33, and 70.54%, respectively compared to the adipocyte control, respectively(p<0.05). Conclusion: These results imply that heated onion peel extract is a functional natural ingredient possessing potential inhibitory fat accumulation.
