Identification of Non-Volatile Compounds Generated during Storage That Impact Flavor Stability of Ready-to-Drink Coffee

Identification of Compounds That Impact Consumer Flavor Liking of American-European Hazelnut Hybrids Using Nontargeted LC/MS Analysis

American-European (Corylus americana × Corylus avellana) hazelnut hybrids are being developed for the Midwest-growing region of the United States. However, an inadequate understanding of the compounds that impact the consumer acceptance of hazelnuts limits breeding programs. Nontargeted liquid chromatography/mass spectrometry (LC/MS) chemical profiles of 12 roasted hybrid hazelnut samples and the corresponding consumer flavor liking scores were modeled by orthogonal partial least squares with good fit and predictive ability (R2Y > 0.9, Q2 > 0.9) to identify compounds that impact nut liking. The five most predictive compounds (1-5) were negatively correlated to flavor liking, selected as putative markers, purified by multidimensional preparative LC/MS, structurally elucidated (nuclear magnetic resonance, MS), quantified, and validated for sensory relevance. Compound 1 was identified as 1″-O-3'-b-glucofuranosyl-1'-O-1-b-glucofuranosyl-(2,6-dihydroxyphenyl)-ethan-4-one. Compounds 2 and 4 were identified as rotamers of 2-(3-hydroxy-2-oxoindolin-3-yl) acetic acid 3-O-6'-galactopyranosyl-2″-(2″oxoindolin-3″yl) acetate, whereas compounds 3 and 5 were identified as rotamers of 1″-O-1'-b-glucofuranosyl-9-O-6'-b-glucopyranosyl-2″-(2″-oxoindolin-3″yl) acetate. Sensory evaluation determined that all compounds were characterized by bitterness and/or astringency. The sensory threshold values of compounds 1-5 were determined to be below the concentrations reported in 91, 83, 41, 25, and 41% of all 12 hybrid hazelnut samples, respectively, indicating they contributed to aversive flavor attributes.

Vicatia thibetica de Boiss: Botany, Traditional Uses, Phytochemistry, Quantitative Analysis, and Pharmacology

BACKGROUND

Vicatia thibetica de Boiss is a common Tibetan medicine used for both medicine and food, belonging to the family Apiaceae. This plant has the functions of dispelling wind, removing dampness, dispersing cold, and relieving pain. It has great development potential and application prospects in food development and medicinal value.

METHODS

The related references on botany, traditional uses, phytochemistry, quantitative analysis, and pharmacology of V. thibetica de Boiss had been retrieved from both online and offline databases, including PubMed, ScienceDirect, Web of Science, Elsevier, Willy, SpringLink, SciFinder, Google Scholar, Baidu Scholar, ACS publications, SciHub, Scopus, and CNKI.

RESULTS

V. thibetica de Boiss exerts nourishing, appetizing, and digestive effects according to the theory of Tibetan medicine. Phytochemical reports have revealed that V. thibetica de Boiss contains flavonoids, coumarins, sterols, and organic acids. Meanwhile, the quantitative analysis of the chemical constituents of V. thibetica de Boiss has been done by means of UPLC-Q-TOF-MS. It has also been found that V. thibetica de Boiss possesses multiple pharmacological activities, including anti-fatigue, anti-oxidant, anti-aging, and non-toxic activities.

CONCLUSION

This paper has comprehensively summarized botany, traditional uses, phytochemistry, quantitative analysis, and pharmacology of V. thibetica de Boiss. It will not only provide an important clue for further studying V. thibetica de Boiss, but also offer an important theoretical basis and valuable reference for in-depth research and exploitation of this plant in the future.

Identification of subthreshold chlorogenic acid lactones that contribute to flavor instability of ready-to-drink coffee

Flavor instability of ready-to-drink (RTD) coffee during storage negatively impacts product quality. Untargeted liquid chromatography/mass spectrometry (LC/MS) analysis was applied to identify chemical compounds that degraded during storage and impacted the flavor attributes of RTD coffee. LC/MS chemical profiles of non-aged and aged coffee samples were modeled against the degree of difference sensory scores by orthogonal partial least squares with good fit (R²Y = 0.966) and predictive ability (Q² = 0.960). The top five predictive chemical features were subsequently purified by off-line multidimensional Prep-LC, revealing ten coeluting chlorogenic acid lactones (CGLs) compounds that were identified by LC/MS and nuclear magnetic resonance (NMR). The concentrations of eight CGLs significantly decreased in the coffee during the 4-month storage. Sensory recombination testing revealed the degradation of 3-O-caffeoyl-ɣ-quinide and 4-O-caffeoyl-ɣ-quinide significantly impacted the flavor stability of RTD coffee at subthreshold concentrations.