As a part of master's thesis we checked the authenticity, quality and the origin of juniper berries (Fructus juniperi) available on the Slovenian market. Juniper berries contain a highe amount of antioxidants, which we confirmed with DPH analysis. The content of total phenolic compounds was determined by the Folin-Ciocalteu method and a positive correlation was found between the content of total phenolic compounds and antioxidant potential of juniper berries, as many phenolic compounds are present in them. Using Fourier transform infrared spectroscopy (FTIR), we determined the presence of certain functional groups in juniper berries, gin and other junipers. We checked the compliance of the product contents for domestic and commercially available junipers and gin with the declaration. The measured alcohol level in junipers was around 40.0 vol.%, which is in accordance with the legislation. The alcohol level in gin samples was in accordance with the declaration, in most samples 37,5 vol.% up to a maximum of 45 vol%. Brinjevec must have alcohol level above 40 % vol. Higher alcohols (1-propanol, 2-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-methyl-1-butanol) and acetaldehyde, ethyl acetate and methanol were determined in brinjevec in gin samples by gas chromatography with a mass detector. Statistically significant differences between juniper berries by country are observed for Cs, V, Pb, Mo, Al, Ba and Na determined by inductively coupled plasma mass spectrometry (ICP-MS). Isotopic composition of carbon and nitrogen (δ13C and δ15N values) were determined in juniper berries and δ13C values in gin and juniper brandy by isotope ratio mass spectrometry. Higher δ13C values were found in gin samples G1, G4, G5, G10, G12 and in juniper brandy B4 which indicates the presence of C4 plants, i.e. sugar from sugar cane or inconsistency with the declaration.
|
