The aims of this work were to use the isotope analysis method to quantify the carbon of the C3 photosynthetic cycle in commercial cashew pulp and its reconstituted juice, and measure the legal limit based on Brazilian legislation in order to identify beverages that do not conform to the norms of the Ministry of Agriculture, Livestock and Food Supply (MAPA). The juices were produced in a laboratory according to Brazilian law. Adulterated juices were also produced with a quantity of cane sugar above the limit permitted by MAPA. The isotopic analyses measured the relative isotope enrichment of the cashew juices and pulps and of their fractions - purified sugar and insoluble solids. The quantity of C3 source was estimated from these results using the isotope dilution equation. To determine the existence of adulteration it was necessary to create a legal limit according to Brazilian law. Seven commercial cashew products (juice and pulp) were analyzed and four were not in agreement with the MAPA norms. The carbon isotope analysis methodology (13C/12C) based on the C3 and C4 photosynthetic metabolisms efficiently measured the C3 source concentration in commercial cashew juices and pulps. The legal limit enabled the identification of beverages not conforming with Brazilian law.
quality; legal limit; carbon-13; IRMS; Anacordium occidentale
