The purpose of this study was to investigate the Maillard reaction–related physicochemical properties of three maize varieties (Kwangpyeongok, Sinhwangok2ho and Gangdaok) after roasting them for different times (0, 15, 25, 40, and 55 minutes). The Maillard reaction is a non-enzymatic browning reaction involving reducing sugars and amino compounds. The content of reducing sugar, the causative agent of the Maillard reaction, decreased as roasting time increased. Gangdaok showed the lowest reducing sugar content of 1.04 mg/g after 55 minutes of roasting. In the elapsed roasting time, chromaticity ‘L’ and ‘b’ values decreased. At 55 minutes of roasting, wherein the Maillard reaction occurred most actively, Gangdaok showed the lowest ‘L’ value of 56.37 and the highest ‘a’ value of 7.60. Gangdaok had superior conditions for inducing the Maillard reaction compared to other varieties, and it is consider that 'flint–type', an endosperm characteristic, may have been the influencing agent. This study detected a total of 52 types of volatile aroma compounds (VACs), of which 28 were produced after roasting. Of the total VACs detected, 2-Formyl-5-methylfuran and 2-Furancarboxaldehyde accounted for 43.8~45.5% and have been confirmed to be the major VACs present in roasted maize. Most of the correlations between the Maillard reaction–related characteristics showed high correlation coefficients.

The effect of roasting intensity and extraction time of coffee bean on the antioxidant activity of roasted ground coffee extract was investigated. Coffee was roasted at 185oC using a rotating fluidized bed roaster for 5.17 (medium roasting) and 6.00 (dark roasting) min, respectively. Both roasted coffees were extracted in 90oC hot water according to the increased extraction time. Until 20 min, an increase in extraction time significantly increased soluble solute, caffeine, brown color, and phenolic compound. The soluble solid and caffeine contents showed no significant difference among medium- and dark-roasted coffee extracts. The brown color intensity and free radical scavenging activity of dark-roasted coffee extract were higher than those of medium-roasted coffee. On the contrary, the total phenolic content of dark-roasted coffee extract was lower than that of medium-roasted coffee. The free radical scavenging activity of coffee extracts showed a positive correlation with brown color intensity, as well as total phenolic content.

This study was investigated the optimal time that enhanced the functional activities of mung beans for use of functional food resources. Mung beans were roasted according three levels of roasting time levels (10, 20 and 30 minutes) at 110℃ and then the physicochemical compositions were determined. The reducing sugar content was decreased with the increased roasting time. Moisture was decreased with increased roasting time, whereas, crude fat, crude ash, crude protein and carbohydrate were increased with prolonged roasting time. The highest contents of total phenol and flavonoid were shown at a roasting condition 110℃ for 30 minutes. The highest inhibitory activities of DPPH radical, ABTS radical and xanthine oxidase was the best at the condition of 110℃ for 30 min. From these results optimal roasting time of mung beans were 30 minutes for use of functional food resources.

This study was performed in order to determine the effect of roasting (160 for 0, 30, 60, 90 min) on the physicochemical characteristics and antioxidant activity of hot water extracts of dried Liriope platyphylla. With respect to Hunter’s color value, lightness and yellowness decreased roasting time increased. The difference (ΔE value) in lightness, redness and yellowness was 15.88 and 22.94 for 30 and 60 min. The 30 min roasted sample contained more soluble solid content (12.7 °Brix) than other samples. The pH and acidity of the 60 min roasted sample were 5.06 and 0.14%, respectively. The highest contents in reducing sugar and total phenolic compounds contents was obserned in the 60 min roasted sample (17.68, and 35.01 g/100 g, respectively), and flavonoid content was the highest in the 90 min roasted sample (10.53 mg/100 g). The crude saponin content of the 90 min roasted sample (21.90 mg/100 g) was higher than that of others samples (8.0-15.36 mg/100 g). Moreover, ginsenosides such as Re, Rg3, and Rh2, were detected, among which the Rh2 content was the highest. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (31.64-53.72%), 2,2'-azinobis(3-ethylbenzothiazoline)- 6-sulfonic acid (ABTS) radical scavenging activity (61.59-96.71%), and the ferric reducing antioxidant power (72.38-183.11%) were higher in the roasted samples than in the control group. As a result, we confirmed that roasting increased the amount of active compounds, which increased the yield of useful extract.

가정용 소량의 볶음용 참깨 최적 볶음온도 및 시간은 팽창율, 색도, 착유량, 관능평가 등을 고려해 보았을 때 220℃ 에 3분간 처리가 적당하였고, 참기름용 최적 볶음온도 및 시간은 220℃ 에 5분간 처리가 가장 적당한 것으로 나타났다. 볶음처리 조건시험에서는 변온처리 효과는 고정온도 처리보다는 적은 것으로 나타났으며, 고정온도 처리가 볶음참깨 및 참기름 가공에 적합한 것으로 사료되었다. 가공용 대용량의 볶음참깨 볶음온도는 흰깨, 검은깨 모두 240℃ 에 15분간 처리가 총평에서 가장 높은 평점을 받아 대용량으로 참깨를 볶아서 가공할 때는 소량으로 볶았을 때 보다 20℃ 정도 더 높은 온도처리가 적절한 것으로 사료되었다. 대용량의 참기름 가공용으로 사용하기 위한 대용량 참깨 복음온도는 흰깨는 280℃ 에 10분간 처리가, 검정깨는 260℃ 에 15분간 처리가 총평에서 가장 높은 평점을 얻었고, 검정깨 보다는 흰깨는 더 높은 온도로 처리되어야 함을 알 수 있었다.