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To design a consumer-oriented package that complements the taste and aroma of ready-to-drink chilled-cup coffee beverages by using the food kansei model, the effects of the diameter and the color of drinking straws as well as the cognition terms of coffee on consumer sensory characteristics and preferences were investigated. Variance and factor analyses of the sensory scores for chilled-cup coffee with milk and sugar using straws of different diameters, as rated by consumer panelists, extracted two perceived factors (F1, contribution ratio 36.5%, and F2, 28.6%). A two-dimensional plot of the average F1 and F2 scores of 123 panelists showed that the perceived characteristics of the same taste and aroma varied according to the straw diameter. An image investigation of different straw colors and another sensory evaluation using “black,” “brown,” and “green” straws were also performed. A principal component analysis of the image data revealed that the sensory characteristics of coffee with milk and sugar were imaged from the straw color. The second evaluation suggested that the images of straw colors affected the sensory characteristics. In addition, cluster and multiple-comparison analyses of Internet research data from consumers regarding the cognition terms for coffee exhibited three clusters representing the cognitive characteristics of terms by consumers and by developers and the differences of attractiveness degree on the cognition terms due to the consumers’ personal attributes. These studies provide useful information for the development of packages of chilled-cup coffee beverages.

Differences in flavor characteristics of coffee drinks originating from different thermal sterilization processes (ultra-high temperature (UHT) and retort sterilization) were investigated. The sensory evaluation by an analytical panel revealed that the sensory characteristics of a retort-sterilized product were significantly different from those of unsterilized and UHT-sterilized products, suggesting that the sensory characteristics of the UHT-sterilized product are more similar to those of the unsterilized product. The results of gas chromatography/olfactometry analysis revealed three odorants (2-furanemethanethiol, 3-(methylthio)propanal, and 3-mercapto-3-methylbutyl formate) whose flavor dilution (FD) factors decreased in the unsterilized, UHT-sterilized, and retort sterilized products in this order and eight odorants (2-((methylthio)methyl)furan, 3-mercapto-3-methyl-1-butanol, 3-methylbutyric acid, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 4-methylphenol, and three unidentified odorants) whose FD factors increased in the unsterilized, UHT-sterilized, and retort sterilized products in this order. Changes in these odorants, which decrease or increase with an increase in the F0 value (sterilization value), which serves as an indicator of heating, supported the sensory evaluation results that the retort-sterilized product is significantly dissimilar to the unsterilized and UHT-sterilized products. Electronic nose and taste-sensing measurements further supported the sensory evaluation results.

A quick (headspace: 1 min and retronasal aroma simulator (RAS): 2 min) sampling method for capturing volatiles released from coffee drinks by solid-phase microextraction (SPME) (fiber type; divinylbenzene (DVB)/carboxen/polydimethylsiloxane (PDMS)) has been applied to freshly brewed espresso and cafe latte (espresso and milk). Headspace volatiles and volatiles in the RAS effluent were collected from espresso and cafe latte, and examined by gas chromatography/mass spectrometry (GC/MS) and GC/olfactometry (GC/O, CharmAnalysis™). When milk was added to espresso in 60% by weight, aroma release (odor activities) was generally suppressed, both in headspace and RAS aromas. The relative charm value of sweet-caramel odor increased in the headspace aroma, while the phenolic odor increased markedly and the smoke-roast odor decreased in the RAS aroma. These results suggested that milk addition had different effects on the headspace and RAS aromas.

The characteristic volatile compounds released during the grinding of roasted coffee beans are as attractive for coffee-flavored products as the aroma of fresh-brewed coffee itself. In this study, the volatile compounds released during the grinding of various roasted robusta coffee beans (originating in Vietnam and Indonesia ; roasting degree L26, L23, and L18) were collected by exposing a solid-phase microextraction (SPME) fiber to nitrogen gas discharged from a glass vessel in which the electronic coffee grinder was enclosed. Identification and characterization of the volatile compounds were achieved using gas chromatography/mass spectrometry (GC/MS) and GC/olfactometry (GC/O), and by applying principal component analysis (PCA) to the GC/O results. The variation in volatile compounds released during grinding, based on origin, roasting degree and species, is described and compared with the results of a previous study on the compounds released during grinding of roasted arabica coffees.