Rita Margarete Donato Machado

Presença dos ácidos benzóico e sórbico em vinhos e sidras produzidos no Brasil

This study determined benzoic and sorbic acid contents in Brazilian wines and ciders in order to verify whether these preservatives are used in accordance with Brazilian regulations. Forty-nine samples of commercially available wines (35 red wines, 11 white wines and 3 ciders) were analyzed by HPLC coupled to a photodiode array detector. Although the use of benzoic acid in wines and ciders is not permitted, this preservative was detected in three samples, one wine and two ciders, which contained benzoic acid levels of 295.6, 424.7 and 608.4 mg.L-1, respectively. Sorbic acid was detected in 49% of the analyzed samples, with levels ranging from 91.0 to 309.5 mg.L-1. Considering only the samples containing sorbic acid, the mean content detected was 171.2 mg.L-1. Six red wine samples presented sorbic acid content above the maximum level allowed by Brazilian regulations. The results showed that, in some cases, the content of benzoic and sorbic acids in wines and ciders, as well as their labels, do not meet current national regulations.This study determined benzoic and sorbic acid contents in Brazilian wines and ciders in order to verify whether these preservatives are used in accordance with Brazilian regulations. Forty-nine samples of commercially available wines (35 red wines, 11 white wines and 3 ciders) were analyzed by HPLC coupled to a photodiode array detector. Although the use of benzoic acid in wines and ciders is not permitted, this preservative was detected in three samples, one wine and two ciders, which contained benzoic acid levels of 295.6, 424.7 and 608.4 mg.L–1, respectively. Sorbic acid was detected in 49% of the analyzed samples, with levels ranging from 91.0 to 309.5 mg.L–1. Considering only the samples containing sorbic acid, the mean content detected was 171.2 mg.L–1. Six red wine samples presented sorbic acid content above the maximum level allowed by Brazilian regulations. The results showed that, in some cases, the content of benzoic and sorbic acids in wines and ciders, as well as their labels, do not meet current national regulations.

Determinação de glicoalcalóides em batatas in natura (Solanum Tuberosum L.) comercializadas na cidade de Campinas, Estado de São Paulo

Potato is included among the main horticultural crops in Brazil. Due to its broad availability and nutritional characteristics, it has been considered one of the most important components in the human diet. Nevertheless, members of the family Solanaceae produce potentially toxic compounds known as glycoalkaloids during growth and post-harvest, amongst which a-solanine and a-chaconine predominate. The recommended safety level for these compounds in unprocessed potato tubers for human consumption, expressed as total glycoalkaloids, is 200mg·kg-1. In this study, samples of potato tubers of different commercial varieties collected in the city of Campinas, State of Sao Paulo, were extracted and analysed for their total glycoalkaloid (TGA) content using a C18 HPLC column with a photodiode array detector. The mean recoveries of a-solanine and a-chaconine were 102.6% and 100.2%, respectively. The limit of quantitation was 2.5µg·mL-1 for a-solanine and 1.4µg·mL-1 for a-chaconine. The levels of TGA in individual samples of whole tubers of different varieties and type (Bintje, Monaliza, Asterix and Bolinha), ranged from 22.4 to 246.9 mg·kg-1. In 82% of the samples the levels of TGA were below 100mg·kg-1, which indicates that the studied potatoes were safe for human consumption.