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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 antiobesogenic effects of the inhalation of volatile compounds derived from basil essential oil (BEO) in high fat diet‐induced obese rats. A total of 47 volatile compounds were identified in BEO using gas chromatography‐mass spectrometry. Major volatile compounds identified by olfactory testing include linalool oxide, linalool, 1‐menthene, and carvone. White adipose tissue significantly decreased in the rats that inhaled 0.3% BEO (more than +10%) compared to the control. Plasma marker analysis showed increased high‐density lipoprotein‐cholesterol (ca. double fold) and decreased low‐density lipoprotein‐cholesterol (more than −30%) levels in inhaled 1% BEO group compared to the control. Leptin significantly decreased in the 0.3 and 1% BEO groups (more than −70 and −85%, respectively). Last, systolic blood pressure at week 12 was significantly lower in inhaled 1% BEO group (more than −15%) compared to the control. The results of this study suggest that BEO inhalation may be effective in managing plasma lipid markers (cholesterols and leptin) and possibly metabolic disorders such as obesity. Practical Application: Changes in metabolic health markers, which are effected by inhalation of volatiles in basil (Ocimum basilicum) essential oil, will provide physiological variations in vivo to the public. In this study, the opposite effects were identified between 0.3% and 1% inhalation, respectively. Therefore, our findings will provide optimized and useful guidance for inhalation of basil essential oil. [ABSTRACT FROM AUTHOR]

This study aims to investigate the taste and odor characteristics of broccoli by different thermal processes. For electronic tongue analysis, sourness and umami tastes increased after thermal processing, however, saltiness, sweetness, and bitterness decreased after thermal processing. Among all broccolis, air‐fried broccoli was the highest sourness (6.9) and umami (7.8) tastes, however, saltiness (8.7), sweetness (6.2), and bitterness (10.0) were the highest in the raw broccoli. For electronic nose analysis, a total of 28 volatiles were identified. Among sulfur‐containing compounds, methanethiol and 2,4,5‐tirmethylthiazole were identified as major volatiles in the raw broccoli, however, these volatiles were decreased upon thermal processes. In addition, dimethyl disulfide, 2‐methyl‐3‐furanthiol, and 2‐acetylthiazoline may be generated by thermal processes. In multivariate analysis, the flavor dissimilarity between oven‐heated and microwaved broccolis showed the lowest dissimilarity among all broccolis. Raw broccoli showed the highest dissimilarity among all broccolis. This study is believed to be the first study demonstrating flavors in broccoli by different thermal processing. Novelty impact statement: The present work further investigates the effects of various heating processes, including blanching, oven‐heating, microwave heating, and air‐frying. Thus, this study will be utilized by researchers and food industry that are interested in consuming cooked broccoli. The changes in tastes and odors in thermally processed broccolis were rarely reported. Therefore, this study will be considered worthy that contributes to basic data for further study to characterize flavor and taste in broccoli. [ABSTRACT FROM AUTHOR]

Platycodon is a ubiquitous plant widely grown in Asia. This study investigated changes in odor/aroma associated sensory attributes and chemical properties in Platycodon grandiflorum roots upon roasting. Amino acid analysis, electronic tongue analysis, chemical property analysis, volatile compound analysis, GC‐olfactometry‐assisted sensory attributes, and electronic nose analysis were performed. In results, amino acid profiles showed diverse patterns. Electronic tongue analysis somewhat corresponded to the free amino acid profiles. Total phenolic content, antioxidant capacity, and browning intensity significantly increased up to 4 min and slightly decreased afterward. Various pyrazines relevant to roasted odor such as 3‐ethyl‐2, 5‐dimethyl‐pyrazine, and 2, 6‐dimethyl‐pyrazine were generated by roasting. In electronic nose analysis, positive odor parameter significantly increased and potential unpleasant odorants significantly decreased over time. This is believed to be the first study demonstrating overall insight on odor/aroma and chemical characteristics and utilizing objective sensory measures on roasted Platycodon grandiflorum roots for food applications. Practical applications: This study will be utilized (a) to researchers and food companies who are interested in medicinal foods (b) to individuals and food industry that search for changes in sensory characteristics and chemical changes of foods induced by roasting, and (c) to farmers and crop producers who look for utilization and applications of Platycodon grandiflorum roots as food sources and ingredients. [ABSTRACT FROM AUTHOR]

This study aims to investigate alterations in volatile compounds and chemical components that may affect the sensory properties of Cynanchi wilfordii roasted at 120 °C and 180 °C for various durations of time (0 to 4 min). For volatile compound profiles, tridecane, tetradecane, and ethyl hexyl ether were detected as major compounds of the sample without roasting. As the roasting temperature increased, the types of volatile compounds increased, whereas the content decreased with an increase in heterocyclic compound generation. The sample roasted at 120 °C for 1 min showed a notably different profile pattern from the other roasted samples. For the sniffing test performed by trained panelists using gas chromatography olfactometry, naphthalene and nonanal, which induce spicy and raw C. wilfordii, respectively, were perceived most intensely throughout all the samples. In the electronic tongue analysis, the sample roasting at 180 °C showed an increased and decreased pattern in umami taste and saltiness, respectively, with increased roasting time. Electronic tongue analysis results showed that the sample roasted at 180 °C for 4 min would have the best sensory preference. Along with the volatile compound profiles, the sample roasted at 120 °C for 1 min had more sourness than the other samples, and would potentially have distinctive sensory characteristics. This study should provide baseline data on variations in the sensory properties and industrial applications of C. wilfordii upon roasting. Practical Application: Various applications of food ingredients through changes in sensory characteristics by roasting will provide consumers more options for food selections. Accordingly, this study will be utilized by (1) individuals and food companies who are interested in functional foods, (2) individuals and food industries that seek optimum roasting conditions for proper sensory characteristics of foods, and (3) farmers and crop producers who seek for utilization the applications of Cynanchi wilfordii as a food ingredient. [ABSTRACT FROM AUTHOR]

Pet owners think of their animals as part of their family, which further promotes the growth of the pet food market, encouraging pet owners to select nutritious, palatable, and high-quality foods for pets. Therefore, the evaluation of taste and volatile compounds in pet foods is essential to improve palatability. In this study, the sensory characteristics of taste and odor compounds in 10 commercially available dry dog foods were investigated using electronic tongue (E-tongue), electronic nose (E-nose), gas chromatography–mass spectrometry (GC-MS), and gas chromatography–olfactometry (GC-O). Dry dog foods were separated based on the sensory properties of taste and volatile compounds through the multivariate analysis of integrated results of the E-tongue and E-nose. A total of 67 odor active compounds were detected through GC-MS and GC-O, and octanal, nonanal, 2-pentyl furan, heptanal, and benzaldehyde were identified as key odor compounds which may have positive effects on food intake. The multivariate analysis was used to classify samples based on key odor compounds. Volatile compounds responsible for aroma properties of samples were evaluated using GC-O and multivariate analysis in this present study for the first time. These results are expected to provide fundamental data for sensory evaluation in producing new dog foods with improved palatability. [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]

• Excessive oven-roasting of pomegranate seeds breaks down the innate carotenoid pigments and reduces the a* (redness) value. • Oven roasting increases the total phenolic and flavonoid content of pomegranate seeds, which improves their antioxidant capacities. • Proper roasting conditions increase antioxidant properties and positive flavors such as furan derivatives, pyrazines. • Higher temperatures and a long roasting time increase the amounts of off-flavor such as sulfur compounds and amines. This study investigated the effects of oven-roasting temperature (160, 180, and 200 ℃) and time (5, 10, 15, and 20 min) on pomegranate seeds. Physicochemical properties, such as color (L*, a*, and b* values), browning index (BI), total phenolic and flavonoid contents, 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity, and chemosensory properties, including taste and volatile compounds, were analyzed. The L* and a* values, and level of sourness, umami, sweetness, and terpenes decreased, whereas the b* value, BI, and level of saltiness, bitterness, furan derivatives, pyrazines, and sulfur-containing compounds, increased with roasting time. The findings of this study showed that the positive roasting conditions for pomegranate seeds were 10–20 min at 160 ℃ and, 5–10 min at 180 ℃. This study is expected to be used as a primary reference for selecting the optimal oven-roasting conditions in which positive effects appear and for developing products utilizing pomegranate seeds. [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]

This paper reviews the research and development results achieved in the Korea Electrotechnology Research Institute (KERI) in a decade. KERI develops pulsed power technology and its applications are mostly based on power electronics. KERI's research and development activity covers components, military systems, and industry applications. High-voltage switching means developed in KERI are a rotary arc gap (RAG) switch (11 kV and 400 kAp), a vacuum RAG (20 kV and 150 kAp), an inverse pinch switch (20 kV and 150 kAp), and 10-kV semiconductor switch stacks made of thyristors and Insulated Gate Bipolar Transistors (IGBTs). The IGBT and thyristor stacks consist of 10 or 12 1.2-kV discrete devices and are operated by only one active drive circuit installed in the groundside. Some ferromagnetic opening switch schemes are also researched on trial bases. Some of KERI's research and development works from devices to application systems will be described. [ABSTRACT FROM AUTHOR]

This study investigated the changes of physicochemical and flavor characteristics of Angelica gigas Nakai roots during roasting. Glutamic acid and arginine were higher in constituent amino acids. In the taste value, glutamic acid was highest in constituent and free amino acids. Total phenol contents were highest in 0 min and lowest in 3 min. Hundred twenty‐six volatile compounds were detected by GC/MS during roasting. α‐pinene, eudesmol, nonane, and limonene were detected as major volatile compounds. For antioxidant ability, 1,1‐diphenyl‐2‐picrylhydrazyl did not change during roasting, and 2,2′‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulphonic acid showed the highest value in 3 min. Browning intensity showed a slight decrease over time. In Electronic nose, fragrance increased by roasting, and strength, NH3, and H2S decreased significantly. In Electronic tongue, sweetness, bitterness, and umami taste increased by roasting, and this was related to amino acid composition. The results provide basic data on the physicochemical and flavor characteristics of A. gigas Nakai according to the roasting process. Practical applications: Angelica gigas Nakai has been known as a medicinal herb in Asian countries and usually consumed in powder, tea, and snacks. In order to produce the powder, tea, or snacks with A. gigas Nakai, thermal treatment is an essential and critical process. Despite that existing studies reported many physiological benefits and functional properties of A. gigas Nakai, studies have rarely discovered how the nutritional properties and volatile compounds of A. gigas Nakai alter when it undergoes thermal treatment. Therefore, this study will be utilized as basic data to optimize the thermal processing conditions (e.g., roasting time) for the production of food products with A. gigas Nakai such as tea and snacks. This study further provides objective chemical measures of sensory profiles of A. gigas Nakai using electronic tongue and electronic nose during the thermal processing. [ABSTRACT FROM AUTHOR]

This study investigated changes of volatile compounds, sniffing test-assisted sensory properties, taste associated-constituent and free amino acid compositions, taste description by electronic-tongue, and chemical characteristics in Perilla frutescens Britton var. acuta Kudo after roasting at 150 °C for 0–8 min. A total of 142 volatile compounds were identified, among which methyl benzoate and limonene were predominant, regardless of roasting time, and these were also detected as the major compounds in the sniffing test by GC-olfactometry. For constituent amino acids analyzed by the acid hydrolysis method using hydrochloric acid (HCl), the concentration of glutamic acid, aspartic acid, and leucine showed an increase pattern with increased roasting time, which results in umami taste, sour taste, and bitter taste, respectively. For free amino acids, valine and hydroxylysine eliciting bitter and bitter and sweet tastes, respectively, also tend to increase by roasting. The pattern of amino acid concentration by roasting was readily matched to the taste description by electronic-tongue but that of sweetness and sourness by electronic-tongue did not coincide with the amino acid composition. For the chemical properties, total phenolic content, antioxidative capacity, and browning intensity tend to increase with roasting but decreased by 8 min. The results of this study provide fundamental information on perilla in both the food industry and cooking environment for the sake of increasing the utilization of perilla as a food source and ingredient. [ABSTRACT FROM AUTHOR]