Consumer Expectation of Flavored Water Function, Sensory Quality, and Sugar Reduction, and the Impact of Demographic Variables and Woman Consumer Segment

Characterization of the key differential aroma compounds in five dark teas from different geographical regions integrating GC-MS, ROAV and chemometrics approaches

Dark tea (DT) holds a rich cultural history in China and has gained sizeable consumers due to its unique flavor and potential health benefits. In this study, headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS), relative odor activity value (ROAV), and chemometrics approaches were used to detect and analyze aroma compounds differences among five dark teas from different geographical regions. The results revealed that the five DTs from different geographical regions differed in types, quantities, and relative concentrations of volatile compounds. A total of 1372 volatile compounds of were identified in the 56 DT samples by HS-SPME-GC-MS. Using ROAV and chemometrics approaches, based on ROAV>1 and VIP>1. Eighteen key aroma compounds can be used as potential indicators for DT classification, including dihydroactinidiolide, linalool, 1,2,3-trimethoxybenzene, geranyl acetone, 1,2,4-trimethoxybenzene, cedrol, 3,7-dimethyl-1,5,7-octatrien-3-ol, β-ionone, 4-ethyl-1,2-dimethoxybenzene, methyl salicylate, α-ionone, geraniol, linalool oxide I, linalool oxide II, 6-methyl-5-hepten-2-one, α-terpineol, 1,2,3-trimethoxy-5-methylbenzene, and 1,2-dimethoxybenzene. These compounds provide a certain theoretical basis for distinguishing the differences in five DTs from different geographical regions. This study provides a potential method for identifying the volatile substances in DTs and elucidating the differences in key aroma compounds. Abbreviations: DT, dark tea; FZT, Fuzhuan tea; LPT, Guangxi Liupao tea; QZT, Hubei Qingzhuan tea; TBT, Sichuan Tibetan tea; PET, Yunnan Pu-erh tea; ROAV, Relative odor activity value; OT, Odor threshold; HS-SPME, Headspace solid-phase microextraction; GC-MS, Gas chromatography-mass spectrometry; PCA, Principal components analysis; PLS-DA, Partial least squares-discriminant analysis; HCA, Hierarchical clustering analysis.

Effects of brewing water on the volatile composition of tea infusions

There is a huge demand for brewing water in tea consumption, and the sensory flavor of tea infusion is significantly affected by the water used for brewing. To investigate the impact of brewing water on the aroma of tea infusions made from Camelia senensis, the three tea infusions of green, oolong and black tea brewed by six different drinking waters were analyzed by sensory evaluation, solid-phase microextraction, gas chromatography-mass spectrometry, and chemometrics. Brewing water with high pH values (>8.10) and high TDS content (>140 ppm) resulted in a lower overall aroma acceptability for tea infusion, where HCO3-, Ca2+ and Mg2+ were key influencing ions. A total of 86, 106, and 131 volatiles were identified in green, oolong and black tea infusions, respectively, which were strongly influenced by six different brands of waters. Decanal, dimethyl sulfide, β-ionone and linalool were potent volatiles in tea aroma changes caused by brewing water.

Erosive potential of vitamin waters, herbal drinks, carbonated soft drinks, and fruit juices on human teeth: An in vitro investigation

Background

Dental erosion is the loss of dental hard tissues through the acid dissolution of tooth minerals. One of the major factors that cause erosion is the consumption of acidic food and drinks. This study investigated and compared the effect of vitamin waters, herbal beverages, carbonated soft drinks, and fruit juices on the loss of human dental hard tissue.

Methods

Human tooth samples were immersed in various drinks: vitamin waters, herbal beverages, carbonated soft drinks, and fruit juices. The pH value of each drink was measured using a pH meter. The weight of each sample was determined before and after six days of immersion in the tested drink, and the weight loss percentage was calculated. The exposed tooth surfaces were also examined under a scanning electron microscope.

Results

Most of the tested drinks were acidic and displayed pH values lower than the critical pH for enamel erosion. Significant weight loss of the tooth samples was found in all tested drink groups. Additionally, the samples immersed in fruit juices and herbal beverages exhibited significantly greater weight loss than those immersed in carbonated soft drinks. Scanning electron micrographs showed samples immersed in the tested drinks to demonstrate structural disintegration with occasional void spaces, except for samples immersed in Doi Kham® Lemongrass drink.

Conclusion

Most of the tested drinks have the potential to cause dissolution and destruction of dental hard tissues. Consumers should be aware that prolonged exposure to these drinks could lead to permanent loss of tooth mineral and dental erosion.

Food Perception: Taste, Smell and Flavour

Flavor is the most important sensory quality in food [...].

Mushroom-Mediated Reductive Bioconversion of Aldehyde-Rich Essential Oils for Aroma Alteration: A Rose-like Floral Bioflavor from Citronella Oil

The bioflavors are of high demand in food and beverage industries. The current study identified reductive processes mediated by mushroom species to alter the aroma of aldehyde-rich essential oils in the submerged culture. Neofomitella polyzonata, a polypore mushroom, reduced citronellal and citral in the citronella oil into corresponding alcohols that altered the oil aroma, creating a new bioflavor. The screening with 43 aldehydes showed its broad substrate scope within aromatic and linear aldehydes, yet influenced by the electronic and steric factors. Under an optimized condition, it efficiently converted up to 1.5 g/L citrusy and sharp citronella oil into a terpene alcohol-rich (citronellol and geraniol) floral, sweet, fresh, and rosy oily product within 12 h. The preparative-scale fermentation in the shake flask followed by distillation, an organic solvent-free downstream process, furnished the product in 87.2% w/w yield. Detailed sensory analyses and volatile chemo-profiling established the uniqueness in the product aroma and identified citronellol and geraniol as the key odorants. The chemometric analysis found best compositional similarity of this product with Damask or Turkish rose oils. The preference test for the water flavored with the fermented product (0.001-0.005% v/v) indicated its potential as a rosy bioflavor for the beverages.