GC-MS Untargeted Analysis of Volatile Compounds in Four Red Grape Varieties (Vitis vinifera L. cv) at Different Maturity Stages near Harvest

Catalytic infrared radiation dry-peeling Technology for non-Frozen and Frozen Grapes: Effects on temperature, peeling performance, and quality attributes

This study introduces catalytic infrared radiation (CIR) heating technology as an eco-friendly alternative to conventional grape lye peeling (LP). The effects of heating time and distance on non-frozen and frozen grapes were assessed for temperature, peeling performance, and quality attributes. The findings indicate that CIR heating achieves complete dry-peeling of grapes. Extended heating times and reduced distances improve peeling performance, with more favorable results observed in frozen grapes compared to non-frozen ones. Grapes peeled using CIR demonstrated enhanced hardness, color, sugar-acid ratio, bioactive compounds, and antioxidant capacity, compared to those peeled using LP. Importantly, the frozen samples preserved their quality after CIR dry-peeling treatment. Based on peeling performance and quality attributes, the optimum heating times are established at 160 s for non-frozen grapes and 50 s for frozen grapes, at a heating distance of 5 cm. Therefore, CIR dry-peeling is recommended as an eco-friendly and quality-enhancing sustainable grape processing technology.

The Content of Volatile Organic Compounds in Calypogeia suecica (Calypogeiaceae, Marchantiophyta) Confirms Genetic Differentiation of This Liverwort Species into Two Groups

Calypogeia is a genus of liverworts in the family Calypogeiaceae. The subject of this study was Calypogeia suecica. Samples of the liverwort Calypogeia suecica were collected from various places in southern Poland. A total of 25 samples were collected in 2021, and 25 samples were collected in 2022. Volatile organic compounds (VOCs) from liverworts were analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 107 compounds were detected, of which 38 compounds were identified. The identified compounds were dominated by compounds from the sesquiterpene group (up to 34.77%) and sesquiterpenoids (up to 48.24%). The tested samples of Calypogeia suecica also contained compounds belonging the aromatic classification (up to 5.46%), aliphatic hydrocarbons (up to 1.66%), and small amounts of monoterpenes (up to 0.17%) and monoterpenoids (up to 0.30%). Due to the observed differences in the composition of VOCs, the tested plant material was divided into two groups, in accordance with genetic diversity.

Application of benzothiadiazole to Cabernet Gernischt grapes (Vitis vinifera L.) for quality improvement: Effects on aroma metabolism precursors and related genes expression

Pre-harvest spraying of benzothiadiazole (BTH) can improve the winemaking properties of grapes, especially their aroma compounds and phenolics. Limited research has explored the molecular mechanisms by which BTH influences the accumulation of grape aroma precursors during early grape development. This study investigated the effects and putative molecular mechanisms of applying 0.37 mM BTH through whole-plant spraying on the accumulation of aroma metabolism precursors and gene expression in Cabernet Gernischt grapes during ripening. The results showed that BTH treatment increased the levels of fructose, alanine, aspartate, threonine, myristic acid, myristoleic acid, palmitic acid, β-cryptoxanthin, norisoprenoids and methoxypyrazines. Contrarily, it decreased the levels of glucose, sucrose, phenylalanine, tyrosine, leucine, valine, glycine, arginine, histidine, total unsaturated fatty acids (particularly linoleic acid), zeaxanthin, lutein, and organic acids. Additionally, BTH upregulated the expression of genes associated with the production and degradation of amino acids, fatty acids, and carotenoids while decreasing the expression of genes involved in the synthesis and degradation of soluble sugars and organic acids. Ten different metabolites, including fumaric acid, were identified as potential biological markers for distinguishing BTH-treated grapes from control grapes. The study demonstrates that BTH treatment had a substantial impact on the concentration and developmental patterns of aroma metabolism precursors. Furthermore, it altered the winemaking characteristics of Cabernet Gernischt grapes by modulating genes associated with the production and breakdown of metabolites.

Food Perception: Taste, Smell and Flavour

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

A Review on Wine Flavour Profiles Altered by Bottle Aging

The wine flavour profile directly determines the overall quality of wine and changes significantly during bottle aging. Understanding the mechanism of flavour evolution during wine bottle aging is important for controlling wine quality through cellar management. This literature review summarises the changes in volatile compounds and non-volatile compounds that occur during wine bottle aging, discusses chemical reaction mechanisms, and outlines the factors that may affect this evolution. This review aims to provide a deeper understanding of bottle aging management and to identify the current literature gaps for future research.