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Summary: Roasting processing was commonly applied to enhance flavour characteristics, and thus this study was to investigate the taste and aroma compounds between broccoli floret and stem during oven‐roasting processes. In electronic tongue analysis, sourness, saltiness, umami, and sweetness in florets showed an increasing tendency during the roasting, however, decreasing bitterness. Besides, In electronic nose analysis, methanethiol was reduced after the roasting processes and other sulfur compounds were generated in oven‐roasted florets and stems. Furthermore, furans were generated after the roasting. Pyridine and pyrazines were only identified in oven‐roasted florets, however, pyrrole was only identified in oven‐roasted stems. Principal component analysis and cluster analysis were conducted based on combined taste and aroma profiles. Broccoli floret roasted at 15 min was affected by numerous variables compared with the others, and broccoli stems roasted at 15 and 20 min were affected by numerous variables. Additionally, the floret roasted at 15 min was the highest dissimilarity amongst all florets, and the stems roasted at 15 and 20 min were the highest dissimilarity amongst all stems. Accordingly, oven‐roasting induced higher changes in taste and aroma characteristics with increasing times. In addition, this research may provide a basis for enhancing the flavour characteristics of broccoli. [ABSTRACT FROM AUTHOR]

This study investigated the effects of four brewing methods (cold and hot brew, espresso, and cezve) on the chemical sensory properties of green and roasted coffee beans (cv. Yellow Bourbon) extract. The caffeine and chlorogenic acid contents of the coffee were analyzed using HPLC. The taste and volatile aromatic compounds of coffee were analyzed using an electronic tongue and nose, respectively, and the results were analyzed using principal component analysis. For the taste components analyzed using the electronic tongue, the degree of separation was relatively large depending on the extraction method, and the degree of separation was larger depending on roasting for the volatile compounds analyzed using the electronic nose. Our findings provide basic data for the coffee industry. Practical Application: The use of an electronic sensor will provide flavor characteristics for four different types of coffee extracted from green beans and roasted beans. In this study, it was confirmed that the extraction method had a greater effect on the taste of coffee, and in the case of the volatile aromatic compounds of coffee, there was a large difference depending on the green beans and roasted beans. Therefore, our findings will provide data based on the sensory properties of coffee. [ABSTRACT FROM AUTHOR]

In this study, the chemosensory components of microwave- or oven-roasted Coffea arabica L. were compared using high-performance liquid chromatography and electronic sensors. The contents of caffeine and chlorogenic acid were the highest in green bean extract and were decreased with micro- and oven-roasting time. The decreases in the content of the two components were observed more in oven roasting. In electronic tongue analysis, green bean extract had a relatively higher bitterness, sweetness, and sourness than others. After the roasting process, the bitterness decreased at 10 min, however, increased after 15 min. In addition, sourness tended to decrease over time. Microwave-roasted extracts were lower shifted than those of oven-roasted extracts during each roasting process. Accordingly, higher changes of taste patterns were represented during oven-roasting processes. In electronic nose analysis, volatile alcohols and esters were abundant in the green bean extract, and thus, these components were considered as the main volatiles in the green bean. Through the roasting process, the number of volatiles has increased. In particular, pyrazines were generated in those of roasted samples, and the amounts of furans increased. These results provide basic data regarding the chemosensory components of Yellow Bourbon and may be utilized to optimize the roasting conditions. • Chemical sensory properties of microwave- or oven-roasted coffee were studied. • Electronic tongue quantified five basic tastes in coffees roasted by microwave and oven. • Total 75 volatile compounds were identified using electronic nose. • Principal component analysis segregated coffee sample clusters with different thermal processing. [ABSTRACT FROM AUTHOR]