The high antioxidant capacity of tea is well-known, but the effect of flavorings like honey or lemon has been less studied. Their antioxidants can interact with each other, the global result being also affected by the brewing temperature.
The combined effect of heat (55 and 80 °C) and flavorings (acacia and honeydew honeys, lemon juice) on the total polyphenol, total flavonoid content and antioxidant capacity of black and green teas was studied.
In many cases higher antioxidant capacity was obtained at 80 °C. Teas flavored with honeydew honey had higher antioxidant capacity than those containing acacia honey. Addition of lemon decreased the antioxidant capacity of tea with honey. No synergies were confirmed in any of the compositions investigated. Vitamin C content of lemon-containing black tea was reduced by half at 80 °C compared to tea brewed at 55 °C; while honey was shown to partly prevent this loss of ascorbic acid.
Hungarian fruit vinegars were characterised in terms of physicochemical attributes (total polyphenol content, antioxidant characteristics/FRAP, CUPRAC, ABTS/, ascorbic acid content, pH, total soluble solids), sensory profiles, and antimicrobial properties.
Both compositional and sensory profiles showed distinct patterns depending on the type of vinegar (Tokaj wine, balsamic or apple) and the additional fruit used. Balsamic vinegars maturated on rosehip, sea buckthorn, and raspberry showed outstanding antioxidant performances. Rosehip, raspberry, and quince vinegars, as well as vinegars produced from Tokaji aszú and balsamic apple obtained high scores for fruity and sweet notes.
Antimicrobial activities were tested on Gram-negative and Gram-positive organisms, including probiotic bacteria. Generally, only weak activities were obtained, which was attributed to the natural sugar content of the samples, depending on the type of the vinegar and the fruit. Similar results, but more pronounced bacterial growth inhibitions were obtained for probiotic strains, however, some probiotic strains were resistant to at least two of the vinegars. Based on these, balsamic apple, raspberry, rosehip, quince, and sea buckthorn may qualify as potential functional components of probiotic preparations containing some of the strains tested.
People have recently started to pay more attention to the healthier lifestyle, which also includes the consumption of more natural and less processed food products. Honey as one of the most often used natural sweeteners has also been reconsidered and more commonly used. However, honey has also been the target of food adulteration due to its emerging use and relatively high price. Therefore, there is an increasing need to develop rapid evaluation methods for the identification of honey from different sources. Experiments have been performed with 79 authentic honey samples of different floral and geographical origins, mainly from Hungary. The standard analytical parameters used to characterize the nutritional values of honey such as antioxidant capacity, polyphenol content, ash content, pH, conductivity have been determined. The samples were also analyzed with a benchtop near infrared (NIR) spectrometer to record their NIR spectra. The data acquired with NIR spectroscopy measurements were evaluated with various univariate and multivariate statistical methods. Results gained with a limited sample set show that NIR spectroscopy might be useful for the identification of floral and geographical origin of honey samples. Further experiments are proposed to build a robust database, which could support the use of NIR spectroscopy as a quick alternative for honey authentication.