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Isotopic analysis was used to characterize authentic samples of orange juice (Citrus sinensis) from Brazil. Site specific natural isotopic fractionation nuclear magnetic resonance (SNIF-NMR) was used to determine deuterium/hydrogen ratios at the methyl [(D/H)I] and methylene [(D/H)II] sites of ethanol produced by fermentation of orange juice. Stable isotope ratio mass spectrometry (SIRMS) was used to determine the ratio of carbon isotopes (13C/12C) in the same ethanol and the ratio of oxygen isotopes (18O/16O) in the citrus juice water. The mean ratios found for these parameters in authentic hand-squeezed orange juice were as follows:  (D/H)I, 102.3 ppm (SD = 1.7); (D/H)II, 126.5 ppm (SD = 1.8); 13C/12C, δ13C = −26.6‰ PDB (SD = 0.9); and 18O/16O, δ18O = +2.27‰ SMOW (SD = 2.48). Retail samples taken from the Brazilian market place were evaluated by comparison against these data. No evidence was found for the addition of sugar to orange juice or for the dilution with tap water of samples labeled as freshly squeezed. Keywords: Authenticity; orange juice; SNIF-NMR; SIRMS; isotopic analysis; D/H; 13C/12C; 18O/16O

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Samples of vegetable oils on the Brazilian market including rape seed, corn, soybean, sunflower, rice, palm and garlic were analysed for benzo(a)pyrene (B(a)P). The analytical method involved liquid-liquid extraction, clean-up on silica gel column and determination by high performance liquid chromatography using fluorescence detection. The limit of detection was 0.5 microgram/kg. Benzo(a)pyrene was detected in almost all samples, at levels up to 58.9 micrograms/kg. The mean levels of B(a)P in rice, sunflower, soybean, corn and palm oils were 1.8, 0.2, 2.2, 10.8 and 2.1 micrograms/kg respectively. No B(a)P was detected in garlic and rape seed oils. The data indicate that the levels of B(a)P found in Brazilian corn oils are relatively higher than those published in the literature for European corn oils.