During the cultivation of wheat sprouts, antioxidant activity was measured during each cultivation period. Wheat sprouts from the cultivation period showing the highest antioxidant activity were added at different concentrations to make wheat sprout sulgidduk. Their physicochemical properties then were measured. As a result, when wheat sprouts were cultivated to about 14 cm, contents of ascorbic acid and polyphenol compounds were the highest. Their ABTS radical scavenging activities also showed high values. Thus, wheat sprouts grown about 14 cm were added at a concentration of 0 to 7% to prepare wheat sprout sulgidduk. The lightness (L) of the control was the highest. Redness (a) and yellowness (b) of wheat sprout sulgidduk increased as the amount of wheat sprout added increased. Contents of ascorbic acid and polyphenol compounds and ABTS radical scavenging activities of wheat sprout sulgidduk added with the highest wheat sprout content were significantly higher than those of others. Regarding the texture, the addition of wheat sprout resulted in slightly higher hardness, gumminess, and chewiness than the control. However, springiness and cohesiveness were not significantly different between treatment groups.

본 연구는 설기떡에 보리수를 이용하여 보리수의 첨가량에 따른 설기떡에 미치는 품질 특성을 알아보고 건강 기능성 떡으로의 이용 가능성을 연구하였다. 1. 보리수의 수분함량은 81.64%이었고, 조단백질은 1.75%, 조지방은 0.81%이었으며 조회분은 0.56% 이었다. 보리수는 다른 과실에 비하여 폴리페놀 함량이 높고 항산화성을 가진 식품소재로서의 가치가 있 는 것으로 나타났다. 2. 보리수를 첨가하여 설기떡을 제조하였을 때 보리수 첨가량이 증가함에 따라 a, b값, 당도, 경도, 탄 력성, 씹힘성, 검성은 높아졌고, 수분함량, L값, pH, 부착성과 응집성은 낮아졌다. 특성차이검사 결과 보 리수 첨가량에 따라 모든 검사 항목이 강하다고 평가되었으며 기호도 검사 결과 보리수 첨가 설기떡의 제조 시 보리수는 4%를 첨가하는 것이 가장 선호되었다. 3. 보리수 설기떡의 저장에 따른 특성은 저장 기간이 지남에 따라 a, b값, 경도, 탄력성, 씹힘성과 검 성은 증가하였으며, 수분함량, L값, 부착성, 응집성은 감소하였다. 저장기간이 길어질수록 총균수는 증가 하였으나 보리수 첨가량이 증가할수록 총균수는 낮아 보리수를 첨가하였을 때 떡의 저장성을 높일 수 있음을 알 수 있었다. 이상의 실험결과 설기떡을 제조할 때 보리수의 첨가량은 4%가 적합한 것으로 사료되며 적절한 보리 수 가루의 첨가는 설기떡의 기호도에 긍정적인 영향을 미치며, 관능적 및 기계적인 품질 특성의 향상이 가능한 것이 확인되었다.

The purpose of this study was to evaluate of black carrot on the antioxidant activity and quality characteristics of Sulgidduk. Sulgidduk was prepared with different amounts (0, 1, 2, 3, 4%) of black carrot. As the amount of added black carrot increased, the moisture content (p<0.05) and pH were decreased (p<0.001). Sugar content results showed the increase with the addition of black carrot (p<0.01). L (lightness) values and b (yellowness) values decreased whereas a (redness) values increased with an increased concentration of black carrot powder (p<0.001). The mechanical texture of Sulgidduk was decreased by the addition of black carrot considering hardness, chewiness and gumminess (p<0.001) while those of springiness, cohesiveness increased. Consumer acceptability test revealed that the 2% black carrot groups had a higher score than the other groups in respect to color, flavor, taste, texture, overall palatability. To examine antioxidant activities of Sulgidduk, total phenolic, DPPH radical scavenging activity, and total anthocyanin were tested. Total phenolic, DPPH radical scavenging activity, and total anthocyanin showed good vitality as amounts of black carrot powder increased (p<0.001). Based on the various aspects of results, 2% of black carrot added into Sulgidduk showed the best functionality and sensory qualities.

In this study, sulgidduk was prepared by addition of varying amount of black doraji extract and the physicochemical quality characteristics and antioxidant activities were investigated in order to explore the commercialization potential of sulgidduk supplemented with black doraji extract. The moisture content of sulgidduck supplemented with black doraji extract exhibited a significant decrease compared to the control. The pH of sulgidduck tended to decrease with increasing concentration of black doraji extract, and the reducing sugar content increased significantly from 0.33% to 3.51%. With an increase in the content of black doraji extract, a decrease in lightness (L*) and increase in redness (a*) was observed. A significant increase in the total polyphenol content and antioxidant activity (DPPH and ABTS radical scavenging activity) was observed with the addition of the black doraji extract. Consequently, it is proposed that black doraji extract can be used for recipe development and commercialization of various rice cakes.

In this study, Seolgi Tteok was made in order to increase consumption of Geuk, which possesses numerous nutritional advantages, and its optimum content as a new food coloring for rice cake was determined. Quality characteristics and quantitative description analysis (QDA) of Seolgi Tteok, in which Geuk was added at 0, 4, 8, and 12%, was conducted. Consumer acceptability test was also conducted. As the amount of added Geuk increased, moisture content of Seolgi Tteok increased as well. Brightness (L-value) was the highest in the control group, and more Geuk resulted in higher values of red index (a-value) and yellow index (b-value), which corresponded to the results of the sensory evaluation. As result of the mechanical texture measurement, only adhesiveness and resilience show a significant difference. As a result of the QDA, 17 sensory characteristic terms were assessed. Among them, only 13 showed a significant difference. Among the different sensory characteristics, almost all of them except for taste characteristics were significantly influenced by the amount of Geuk. The aroma and taste of Geuk were not largely influenced. It can be suggested that Geuk is not a factor that strongly influences flavor. In conclusion, Geuk does not have a strong influence on the taste or aroma of Seolgi Tteok but does on color characteristics. It can be suggested that Geuk is qualified as a coloring material for food, and the reasonable addition amount is 8%. As a result of this research, Geuk can be considered as a coloring material for other types of rice cake, traditional Korean sweets, and even confectioneries as well as for Seolgi Tteok. This implies that Geuk can be utilized to develop various new products as a coloring material with abundant nutritional content, which will contribute to the promotion of Geuk consumption.

This study examined the characteristics of Sulgidduk with different amounts of apios powder (0, 10, 20, 30, and 40%). The moisture content of Sulgidduk significantly increased with the addition of apios powder. Also, the pH values of Sulgidduk significantly decreased with the addition of apios powder. The addition of apios powder in the Sulgidduk decreased the lightness (L) in Hunter’s color value, but increased the redness (a) and yellowness (b). By increasing the quantity of apios powder, the hardness, gumminess, and chewiness of Sulgidduk decreased and its springiness increased. The addition of apios powder in the Sulgidduk increased the total polyphenol content and DPPH-radical-scavenging activity. In the sensory evaluation, the addition of 20, 30% apios powder had the best score in taste and overall preference. This study suggests that apios powder is an excellent ingredient for improving the sensory preference and functionality of Sulgidduk. The study also shows that it was the addition of 30% apios powder can be used to make functional Sulgidduk.

Roselle (Hibiscus sabdariffa L.) is a shrub which grows well in a tropical climate. There are large amounts of anthocyanins, organic acids and other compounds in roselle. Mostly, roselle is cultivated to use its red calyx. Its calyx is used as a natural food colorant and commonly consumed as a tea. This quality study was conducted to investigate the characteristics and antioxidant activities of Sulgidduck with roselle calyx powder. Four samples and a control were made with different ratios of added roselle calyx powder (0.5%, 1%, 1.5%, 2%). The moisture content of the 0.5%-sample was the highest as 40.60%, and that of the 2%-sample was the lowest as 37.37%. The pH of samples significantly decreased from 6.26 to 3.65 as the amount of roselle calyx powder increased (p<0.05). The L-value of samples also significantly decreased (p<0.05). In contrast, a-value and △E of samples significantly increased with elevated amounts of roselle calyx powder (p<0.05). The b-value of roselle calyx added Sulgidduck samples significantly increased compared to the control (p<0.05). Hardness and chewiness of Sulgidduck samples with added roselle calyx also significantly increased compared to the control (p<0.05). Cohesiveness of Sulgidduck samples with roselle calyx significantly decreased compared to control (p<0.05), with the exception of the 1% sample. There were no significant differences in springiness among samples. Total phenolic contents significantly increased when roselle calyx powder was added above a level of 1.5% (p<0.05). The flavonoid content of the control was the lowest as 0.73. ABTS radical scavenging activity significantly increased with increasing amounts roselle calyx powder (p<0.05). The 2%-sample got the lowest sensory preference scores in sweetness and overall acceptability. In contrast, the control and 1%-sample got the highest sensory preference scores. Based on these study findings, addition of 1% roselle calyx powder optimized the preparation of Sulgidduck and roselle calyx is therefore a useful natural colorant and antioxidant.

The effects of substituting whey protein concentrate (WPC) powder for rice flour in the preparation of seolgiddeok were determined by objective and subjective tests. Milk whey is drained from milk curd as a by-product of the cheese manufactureing process. Whey protein is known as a good nutritional source and is a functional material for many processed foods. WPC contains more than 80% whey protein. The moisture content decreased gradually during storage and the decrease in moisture was less in the control than in the WPC powder substituted groups. The color lightness (L) decreased significantly as the amount of WPC powder increased, wherease redness (a) and yellowness (b) both increased. Texture analyses revealed that the hardness, chewiness, gumminess and adhesiveness of seolgiddeok tended to increase in proportion to the amount of WPC powder in the formula. Seolgiddeok gelatinization was investigated by amylographing. Initial pasting temperature, peak viscosity, hot pasting viscosity and breakdown were low in seolgiddeok prepared with WPC powder substituted for rice flour. Setback had the lowest value in the control. Sensory evaluations revealed that, seolgiddeok prepared with 3% WPC powder had the highest overall acceptability score. These results indicated that WPC seolgiddeok with 3% WPC powder has the best quality.

This study investigated the antioxidative properties of Yangha Buds (Zingiber Mioga R) and quality characteristics of Korean steamed-rice cake, Sulgidduk, prepared with Yangha Buds juice. Antioxidative activities were measured based on DPPH radical and ABTS radical scavenging activities, total phenol content, and total flavonoid content in Yangha Buds (water extract and juice). Sulgidduk was prepared by adding Yangha buds at concentrations of 0, 1, 2, 3, and 4% of juice. To analyze quality characteristics, proximate composition, color, texture profiles, and sensory evaluations were measured. As content of Yangha buds juice increased, L-value significantly decreased while a-value and b-value increased (p<0.05). For texture profiles, control group scored higher score for hardness as compared to groups added with Yangha buds juice. Springiness, chewiness, and adhesiveness were not significantly different among the groups. In the sensory evaluation, samples containing 3% Yangha buds juice showed better results for attitude. Based on these results, we suggest that Yangha buds are a good ingredient for increasing consumer acceptability and functionality of Sulgidduk.

The objective of this study was to investigate the quality characteristics of Baeksulgi (BS) and Sulgidduk added with Makgeolli (MS, BS+ Makgeolli) during storage at 20±2 for 3 days. Moisture contents of MS were significantly higher than those of BS during storage. Reducing sugar contents (%) were higher in MS. The pH values were 6.23 and 5.93, for BS and MS, respectively. The pH of MS was lower and thus indicated higher in acidity. The Hunter color L (lightness) and a (redness) values were higher for BS, whereas b (yellowness) value of MS was lower. In the texture analysis, hardness and chewiness of MS were found to be lower, whereas springiness, gumminess, and resilience were higher than those of MS. According to DSC (Differential scanning calorimeter) analysis, enthalpy of MS appeared to be lower than that of BS during storage, which suggests retrogradation of MS was delayed. The total phenol content was higher in MS. The IC50 value of DPPH and hydroxyl radical scavenging activity was lower in MS, which means antioxidant activity increased in MS. Results of the preference test showed that appearance, flavor, taste, and overall acceptability of MS scored higher than those of BS. From these results, high quality of MS was derived from Makgeolli addition.

The results of testing general components, physical property and physical function after having made steamed rice cake by adding eggplant, which caters to consumers’ tastes are as follows. It showed that when eggplant powder content increased, the moisture content of steamed rice cake with eggplant was decreased. It also showed that the lightness value (L) of steamed rice cake with eggplant powder was the highest as 82.75 in the control group. When eggplant powder content increased, the redness (a) and yellowness (b) were increased. From the results of having measured the antioxidant potential over the steamed rice cake with freezing-drying eggplant powder by DPPH radical elimination, we figured out that it was the lowest as 48.30% in the control group. As more eggplant powder was added, its elimination increased accordingly. As per hardness of steamed rice cake with eggplant, the added group with 7% was revealed as the highest at 0.757. It showed that adhesiveness was the lowest as 30.233 in the control group, and springiness and cohesiveness were on the rise as freezing-drying eggplant powder was increased. Furthermore, softness and chewiness were shown to be high in the added group with eggplant powder of 3, 5%. The evaluation over the overall preference was the highest in 5% added group. Judging from this, adding 3~5% eggplant powder against non-glutinous rice powder is considered an optimal quantity in making steamed rice cake with eggplant.

본 연구에서는 약리작용과 기능성이 함유된 국내산 산수유를 설기떡에 활용하여 건강식품으로 보급 발전시키기 위하여 산수유를 설기떡 재료의 최적 배합 비율을 얻고자 하였다. 멥쌀가루에 0, 5, 10, 15, 20%의 동결건조한 산수유 분말을 첨가하여 설기떡을 제조하고 20oC에서 저장하여 시료로 사용하였으며, 수분함량, 색도, 당도, pH, 기계적 품질특성, 관능적 품질특성을 측정한 결과는 다음과 같다. 산수유 분말 첨가량이 증가할수록, 수분 함량이 증가하는 경향을 보였고 색도에서 L값은 감소하였으며, a값과 b값은 증가하는 경향을 나타냈다. 당도는 첨가량이 증가할수록 증가하는 경향을 보였지만 pH 측정값은 낮아졌다. 경도(hardness), 부착성(adhesiveness)은 대조군이 가장 높았고, 첨가량이 증가할수록 낮아지는 경향을 보였다. 응집성(cohesiveness)과 탄력성(springiness)은 산수유 분말 15% 첨가군이 가장 높은 값을 나타냈다. 씹힘성(chewiness)은 대조군과 산수유 첨가량의 유의적 차이는 나타나지 않았지만 산수유 15%일 때 가장 높은 값으로 측정되었다. 관능평가의 전체적인 기호도(overall-acceptability)는 산수유 첨가군 15% > 10% > 20% > 5% > 0% 순으로 나타났다. 따라서, 동결건조한 산수유 분말 첨가량이 15% 수준에서 설기떡에 첨가하여 제조하는 것이 적정한 수준으로 여겨진다.