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The Maillard reaction (MR) involves interactions between reducing sugars and amino acids or proteins during heating, producing Maillard reaction products (MRPs) that influence food flavour, aroma, and colour. Some MRPs exhibit antioxidant properties, prompting interest in their potential as natural food preservatives. This study aimed to develop a method for detecting and identifying antioxidant MRPs using high-pressure liquid chromatography (HPLC) coupled with high-resolution mass spectrometry (HRMS). By improving chromatographic conditions, the separation of antioxidant MRPs was optimised using known antioxidant MRPs as reference signals. This work also examined the effects of pH, reaction time, and different sugar–amino acid combinations on the production and composition of antioxidant MRPs. Results indicated that neutral to basic pH facilitated faster reactions, with pH 7 selected as optimal. A library of 50 m/z signals for potential antioxidant MRPs was created, and the best combinations of amino acids and sugars for their production were identified. These findings pave the way for more precise analyses of antioxidant MRPs, with future research focusing on isolating and characterising specific MRPs to understand their structures and mechanisms, ultimately contributing to the development of functional foods with natural antioxidant properties. [ABSTRACT FROM AUTHOR]

The aim of this work was to assess the effect of in vitro human digestion on the chemical composition (carbohydrates and phenolic compounds) and bioactivity of hydro-alcoholic-acid pomace extracts from two mandarin varieties (Clemenule and Ortanique) by measuring their antioxidant, antidiabetic, anti-glycative, hypolipidemic, and anti-inflammatory properties. The phenolic compound profile showed that nobiletin was the main flavonoid found in the extracts and digests of Clemenule pomace and extract, while isosinensetin/sinensetin/tangeretin were the ones in the Ortanique samples. The digests of Clemenule and Ortanique extracts showed Folin reaction values of 9.74 and 9.20 mg gallic acid equivalents (GAE)/g of sample, ABTS values of 83.2 and 91.7 µmol Trolox equivalents (TE)/g of sample, and ORAC-FL values of 142.8 and 891.6 µmol TE/g of sample, respectively. Extracts (50–500 µg/mL) inhibited intracellular reactive oxygen species (ROS) formation in CCD-18Co cells under physiological and oxidative-induced conditions. Clemenule and Ortanique extract digests showed IC50 values of 13.50 and 11.07 mg/mL for α-glucosidase, 28.79 and 69.64 mg/mL for α-amylase, and 16.50 and 12.77 mg/mL for AGEs, and 2.259 ± 0.267 and 0.713 ± 0.065 mg/mL for pancreatic lipase inhibition, respectively. Ortanique extract (250–1000 µg/mL) inhibited the production of nitric oxide in RAW264.7 macrophages under inflammation-induced conditions, and intracellular ROS formation. In conclusion, altogether, the results supported the potential of mandarin extracts to be used as health promoters by reducing the risk of non-communicable chronic diseases. [ABSTRACT FROM AUTHOR]

La preocupación por el cuidado de la salud y el medio ambiente por parte de los consumidores de vino está aumentando en los últimos años, centrándose el interés en los vinos elaborados con prácticas de producción de bajo impacto en el uso de productos químico. Una de las estrategias potenciales es pasar de un enfoque orientado al tratamiento químico a un enfoque de prevención de enfermedades mediante la utilización de variedades resistentes a hongos, generalmente conocidas como uvas híbridas o cruzamientos interespecíficos. En este estudio, se investigaron los vinos elaborados a partir de cinco variedades resistentes cultivadas en el Instituto Estatal de Viticultura y Enología de Friburgo (Cabernet Cantor, Cabernet Cortis, Cabernet Carbon, Prior y Regent) y provenientes de parcelas experimentales ubicadas en la Provincia de Trento. Los vinos fueron sometidos a evaluación olfativa, y el perfil volátil estudiado por cromatografía de gases-olfatometría (GC-O). Las regiones seleccionadas de los cromatogramas fueron investigadas en detalle por GC-MS.

Among the Moscato grapes, Moscato Giallo is a winegrape variety characterised by a high content of free and glycosylated monoterpenoids, which gives wines very intense notes of ripe fruit and flowers. The aromatic bouquet of Moscato Giallo is strongly influenced by the high concentration of linalool, geraniol, linalool oxides, limonene, α-terpineol, citronellol, hotrienol, diendiols, trans/cis-8-hydroxy linalool, geranic acid and myrcene, that give citrus, rose, and peach notes. Except for quali-quantitative analysis, no investigations regarding the isotopic values of the target volatile compounds in grapes and wines are documented in the literature. Nevertheless, the analysis of the stable isotope ratio represents a modern and powerful tool used by the laboratories responsible for official consumer protection, for food quality and genuineness assessment. To this aim, the aromatic compounds extracted from grapes and wine were analysed both by GC-MS/MS, to define the aroma profiles, and by GC-C/Py-IRMS, for a preliminary isotope compound-specific investigation. Seventeen samples of Moscato Giallo grapes were collected during the harvest season in 2021 from two Italian regions renowned for the cultivation of this aromatic variety, Trentino Alto Adige and Veneto, and the corresponding wines were produced at micro-winery scale. The GC-MS/MS analysis confirmed the presence of the typical terpenoids both in glycosylated and free forms, responsible for the characteristic aroma of the Moscato Giallo variety, while the compound-specific isotope ratio analysis allowed us to determine the carbon (δ13C) and hydrogen (δ2H) isotopic signatures of the major volatile compounds for the first time. [ABSTRACT FROM AUTHOR]