Volatile Profile of Dry and Wet Aged Beef Loin and Its Relationship with Consumer Flavour Liking

This study investigated the effect of ageing method and ageing time on the volatile profiles of grilled beef striploins (Longissimus thoracis et lumborum) and their relationship with consumer flavour liking. Volatiles were measured in grilled steaks subjected to 35 days of dry ageing, 35 days of wet ageing, 56 days of dry ageing or 56 days of wet ageing, using headspace-solid-phase microextraction followed by gas chromatography-mass spectrometry. Gas chromatography-olfactometry-mass spectrometry was also conducted on 35-day wet and dry aged samples to identify volatiles with high odour impact. The concentration of many odour impact volatiles, e.g., 3-hydroxy-2-butanone, 2-acetyl-2-thiazoline, and various alkyl-pyrazines, was significantly higher in dry aged beef compared to wet aged beef (p < 0.05). Several odour impact volatiles, e.g., 2-acetyl-1-pyrroline, and alkyl-pyrazines, decreased significantly with ageing time (p < 0.05), while volatile products of lipid oxidation and microbial metabolism increased with ageing time. Partial least-squares regression analysis showed that the higher consumer flavour liking for 35-day dry aged beef was associated with higher concentrations of desirable odour-active volatiles.

Evaluation of the anti-SARS-CoV-2 properties of essential oils and aromatic extracts.

Essential oils and aromatic extracts (oleoresins, absolutes, concretes, resinoids) are often used as food flavorings and constituents of fragrance compositions. The flavor and fragrance industry observes significant growth in sales of some natural materials during the COVID-19 outbreak. Some companies worldwide are making false claims regarding their essential oils or blends to be effective (or indirectly points towards this conclusion) against coronaviruses even though the available data on the activity of plant materials against highly pathogenic human coronaviruses is very scarce. Our exploratory study aimed to develop pioneering knowledge and provide the first experimental results on the inhibitory properties of hundreds of flavor & fragrance materials against SARS-CoV-2 main- and papain-like proteases, and antiviral potential of the most active protease inhibitors. As essential oils are volatile products, they could provide an interesting subsidiary inhalation therapeutic strategy in the long term.

Evaluation of the inhibitory potential of essential oils and aromatic extracts on SARS-CoV-2 Mpro and PLpro

Essential oils and aromatic extracts (oleoresins, absolutes, concretes, resinoids) are often used as food flavorings and constituents of fragrance compositions. The flavor and fragrance industry observes significant growth in sales of some natural materials during the COVID-19 outbreak. Some companies worldwide are making false claims regarding their essential oils or blends to be effective (or indirectly points towards this conclusion) against coronaviruses even though the available data on the activity of plant materials against highly pathogenic human coronaviruses is very scarce. Our exploratory study aimed to develop pioneering knowledge, and provide the first experimental results on the inhibitory properties of hundreds of flavor & fragrance materials against SARS-CoV-2 main- and papain-like proteases. As essential oils are volatile products, they could provide an interesting subsidiary inhalation therapeutic strategy in the long term.

Comparative Analyses of Volatile Metabolites Associated With Gene Expression From Non-climacteric and Climacteric Melon.

Melon (Cucumis melo L.) is an important species in the cucurbits family with a large economic importance in the world. Two melon cultivars commercially important in Brazil are the cultivars ‘Yellow’ and ‘Gaúcho’. In addition to the economic importance, these two cultivars display phenotypic differences in aroma, a major trait determining fruit quality. Volatile organic compounds (VOC) impart the different aroma found in these fruit and its biosynthesis is associated with fatty acid and amino acid metabolism. Using SPME-GC–MS and RT-qPCR techniques, volatile production and expression of seven genes (CmLOX9, CmLOX18, CmBCAT1, CmArAT1, CmPDC1, CmADH1 and CmAAT1) were determined during maturation and ripening. The climacteric melon ‘Gaúcho’ had a greater number and higher concentration of volatiles than that in the non-climacteric ‘Yellow’ melon. 2-Methylallyl acetate, 4-amino-1-butanol, 2-methylbutanol and ethyl 2-methylpropanoate were found in high concentrations in ripe climacteric ‘Gaúcho’ melons and were major contributors to its strong fruity aroma, but high concentrations of these volatiles were not found in non-climacteric ‘Yellow’ melons. The lipid pathway played a strong role in determining aroma composition in non-climacteric ‘Yellow’ melons. Most volatiles decreased during maturation and ripening explaining the non-aromatic characteristic of this cultivar. In climacteric ‘Gaúcho’ melons, the amino acid pathway was the main one related to the biosynthesis of esters, which contribute to the aroma of this cultivar. Volatile products of the branched chain amino acid pathway correlated with CmADH1 and CmAAT1 expression demonstrating their role in volatile synthesis of this climacteric melon cultivar. In addition, CmPDC1 contributes to the formation of aldehydes at the beginning of this pathway.

Antimicrobial potential of eucalyptus oil and lemongrass oil alone and in combination against clinical bacteria in planktonic and biofilm mode

The use of natural substances has been trending from past few years. In recent years, the synthetic products obtained from plants have gained immense importance. Essential oils and volatile products obtained from plants are the source of food flavoring, aroma products and fragrance industries. Their use is also common to cure different ailments such as cancer, skin problems and nosocomial infections. Vast research has shown the antimicrobial properties of essential oils obtained from plants. Essential oils of lemongrass and eucalyptus have antiviral, antibacterial, antioxidant and insecticidal characteristics. Lemongrass and eucalyptus oils shows their antibacterial activity towards Gram positive bacteria such as Staphylococcus aureus, Bacillus subtilis and Gram-negative bacteria such as Escherichia coli and Klebsiella pneumonia. Combination of these oils also depicts high antimicrobial activity against different strains of bacteria. This review highlights the use of essential oils of lemongrass and eucalyptus for their in vitro antimicrobial properties against different bacteria in planktonic and biofilm mode. Mode of action by which the oil shows its inhibitory activity will be discussed. Susceptibility shown by different bacteria towards these essential oils and their components will be described