H NMR spectrometry for methanol quantification in apple wines and ciders as optimised by comparison to SIDA-HS-GC-MS.

Methanol, a hepato- and neurotoxic compound, is present in apple-based beverages as a by-product of the enzymatic degradation of pectin. Stable isotope dilution assay (SIDA) employing gas chromatography-mass spectrometry (GC-MS) is the state-of-the-art method for methanol determination in beverages. Despite higher initial investment costs, quantitative H NMR spectroscopy (qNMR) is a simpler and faster analytical technique to quantify numerous analytes in liquid foods.

Sun protection by red wine?

Background: There is increasing evidence that polyphenols, antioxidants from plants such as green tea or grapes, may impair the UV-induced erythema reaction as well as carcinogenesis and metastasis of melanoma and epithelial skin cancer. The UVB-protective potential of wine polyphenols has not been studied so far in humans.

Patients And Methods: We tested the influence of local and systemic application of three red wines on the minimal erythema dose (MED) after UVB exposure in 15 healthy male physicians.