This study aimed to examine the possibility of upcycling extracts of Angelica keiskei and Oenanthe javanica juice by-products through comparing enzyme extraction (EE) and complex extraction (CE) methods to increase the extraction yield and flavor of materials. A higher extraction yield was obtained for free amino acid content with EE and CE for A. keiskei and O. javanica juice by-products, respectively, and a higher extraction efficiency was achieved with juice by-products than with extracts prepared from raw materials before juice production. The content of major amino acids varied depending on the extraction method used. When used according to the characteristics of the extract, their use as a functional material was confirmed along with improvement in the flavor of the food. Consistently high extraction yields for organic acid and sugar levels were obtained with CE in A. keiskei and O. javanica juice by-products. The DPPH radical scavenging ability and TPC were consistently high with CE in A. keiskei and O. javanica juice by-products; the increase in extracted content was likely because of the reaction between the ethanol used for CE and the phenolic compounds. However, because the antioxidant capacity of the juice by-product extracts was somewhat lower than that of the extracts from raw materials before juice production, the amount used should be reviewed. The TFC was found to be higher in extracts obtained with EE than with CE for A. keiskei juice by-products; however, no significant difference was observed between EE and CE in the O. javanica juice by-products. Through this study, the taste compounds and antioxidant properties of extracts obtained from juice by-products produced after the production of A. keiskei and O. javanica green juice were analyzed, and the availability of high value-added materials was confirmed. Based on these research results, expanding specific R&D for practical use should be explored.

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

Evaluation of the antioxidant activity of the bakery products is important in order to establish healthy consumption patterns. Aronia and blackberry extract at different levels (0%, 5%, 10%, 15%, and 20%) were used to investigate their comparative effects on the physical properties and antioxidant capacity of cookies. The final cookies were evaluated for physicochemical and sensory properties as well as total phenol content, DPPH radical scavenging activity, and FRAP assay. Substitution of aronia and blackberry extracts significantly (p<0.05) increased the moisture content and spread ratio compared to the control that did not contain the extract. However, types of the extract (aronia or blackberry) did not significantly affects the moisture and spread ratio of cookies at the same concentrations (p>0.05). The lightness and yellowness values of cookies were decreased while the redness value was increased by the amount of the extract compared to control (p<0.05). For textural properties, the hardness and chewiness of cookies were increased by the concentration of extract, and highest at 20% of both extracts. Polyphenol content in the cookies was increased with the concentration of the extract added into the cookies. Consistently, the antioxidant activity was significantly increased as the concentration of the extract was increased (p<0.05). Cookies with aronia extract showed higher antioxidant activity compared to that with blackberry (p<0.05), due to the presence of higher content of polyphenol. In terms of appearance, flavor, taste, texture and overall acceptability, the sensory evaluation scores of cookies with 20% aronia and 10% blackberry were significantly higher compared to the control (p<0.05). Based on above result, using more than 10% of the aronia or blackberry extracts would appropriate for making cookies.

For the development of processed food for hypoglcemia, it is important to construct model system to confirm factors that reduce the glycemic index in real food. This study was to investigate the relationship between the gel model system and real food the high amylose type of segoami using response surface methodology. The independent variables were concentration (X1; 10, 15, 20, 25, and 30%) and steaming time (X2; 30, 35, 40, 45, and 50 min). The predicted glycemic index (Y1) was analyzed as a dependent variable. The regression of pGI was 0.7343, indicating that the model fits the data well in the prediction test. The predict glycemic index of the gel was in the range of 71.38 ~ 83.78, depending on the gel preparation conditions and predicted optimum condition was 23.7% gel concentration and 43.8 minutes of gelatinization. The predict glycemic index of rice gel were decreased with an increase of gel concentration, rather than the steaming time. In order to confirm the effect on in vitro digestibility in real food, the real food (Garraedduk) was prepared by applying the optimal conditions. As a result, there was no significant difference between the predicted value (77.1) and the experiment value (76.6). This result showed that the in vitro digestibility in real food can be predicted by applying the gel model system.

귀리, 콩, 감자, 밀에서 유래한 다양한 식이섬유를 밀가루 대신 10-40%까지 대체함에 따른 수화능, 동적점탄성, 용매흡착능 및 in vitro starch digestion을 비교하였다. 귀리, 콩, 감자, 밀에서 유래한 다양한 식이섬유를 식이섬유의 대체비율이 증가할수록 수분흡착능과 팽윤력은 증가한 반면, 수분용해도는 감소하였다. 밀가루 대신 콩과 감자 식이섬유를 대체함에 따라 동적점탄성은 증가하였으나, 귀리와 밀 식이섬유 대체에서는 오히려 감소하는 경향을 보였다. 식이섬유 대체에 따른 밀가루의 용매흡착능 변화를 분석한 결과, 낮은 대체량의 귀리 식이섬유와 높은 대체량의 콩과 감자 식이섬유가 활용 가능성을 보였다. 원료별 식이섬유 대체 시 밀가루 겔의 전분소화 패턴은 식이섬유 대체비율이 증가함에 따라 glucose 방출은 감소하였으나, 원료별 특성에 따른 유의적인 차이는 없었다. 특히, 밀식이섬유를 제외한 귀리, 콩, 감자 식이섬유는 모두 RDS감소와 RS증가에 따른 pGI 저하를 보여 실제 식품소재로 활용 시 가공적성을 유지할 수 있다면 전분소화지연효과를 기대할 수 있음을 확인할 수 있었다. 한편, 식이섬유의 원료에 따른 식이섬유 조성과 전분소화 관련 특성 간 상관관계를 분석한 결과, 전분소화를 지연시키는 효과는 수용성 식이섬유보다는 불용성과 총식이섬유 함량이 중요한 인자임을 알 수 있었다.

본 연구에서는 떡 굳음방지기술의 적용하여 저장성이 개선된 건강지향형 잡곡 떡을 제조하기 위하여 멥쌀의 일부를 보리 분말 0, 15, 30, 45%로 대체한 가래떡을 제조한 후 4oC에서 3일간 저장하면서 수분, 색도, 텍스처 및 기호도 검사를 수행하였고, 이들간의 상관성을 분석하였다. 떡굳음방지기술을 적용하여 제조한 가래떡의 경도는 보리 분말로 45% 대체한 가래떡을 제외하고 저장 기간이 경과하였음에도 경도 증가가 억제되었다. 색도는 보리 분말 대체량이 증가할수록 명도(L값)는 감소하고, 적색도(a값) 및 황색도(b값)는 증가하였다. 떡 굳음방지기술을 적용한 가래떡의 전반적인 기호도는 제조 직후에는 보리 분말을 함유하지 않은 가래떡이 가장 높은 결과를 보였으며, 보리 분말 대체량이 증가할수록 전반적 기호도는 저하되었으나, 보리분말 0, 15% 대체 가래떡은 저장 3일 후 유의적 차이가 없었다. 가래떡의 기계적 및 관능적 품질 특성 간의 상관관계를 분석한 결과, 가래떡의 전반적인 기호도는 수분 함량과 높은 양의 상관관계를 보였고, 제조 직후와 저장 3일 후 기호도 평가에서는 각각 경도와 점착성이 높은 음의 상관성을 나타내었다(p < 0.01). 이상과 같이, 굳음방지기술을 적용한 보리 분말 대체 가래떡의 저장 후 노화지연, 기계적 텍스처 및 관능적인 기호도를 고려할 때 보리 분말 대체량 15%가 적합한 것으로 사료된다.