ABSTRACT The aim of this study was to evaluate the effect of controlled atmosphere storage on quality of native and cultivated yerba mate produced in Arvorezinha (RS) and São Mateus do Sul (PR) after 0, 3, 6 and 12 months of storage under ambient conditions, low oxygen (1.0 kPa) and high carbon dioxide (3.0 kPa) partial pressures. Total chlorophyll concentration reduced over the storage period regardless of the atmosphere condition, form of cultivation and production region. Total carotenoids, regardless of the form and place of cultivation, decreased until three months of storage under 1.0 kPa O2. Although, the O2 reduction to 1.0 kPa maintains greener color and higher chlorophyll concentration after 12 months of storage. High carbon dioxide partial pressures (3.0 kPa) in the storage chamber increases the polyphenol concentration until six months of storage. The raw material originated from São Mateus do Sul (PR) has higher chlorophyll concentration and greener color, resulting in greater storage potential.

O objetivo deste estudo foi avaliar o efeito da atmosfera controlada na alteração da cor, degradação da clorofila e concentração de compostos fenólicos em erva-mate cancheada e socada. Amostras de erva-mate provenientes de Arvorezinha (RS) e São Mateus do Sul (PR) foram armazenadas em quatro níveis de oxigênio (1, 3, 6 e 20,9kPa de O2) e quatro níveis de gás carbônico (0,3, 6 e 18kPa de CO2), as quais foram analisadas ao final de nove meses de armazenamento. Segundo os resultados, a redução das pressões parciais de O2 reduziu a perda da coloração verde, manteve maior teor de clorofilas e de compostos fenólicos totais. Em relação aos diferentes níveis de CO2, não se constatou uma resposta tão marcante como na de O2. Tanto no armazenamento com O2 como com CO2, a erva-mate cancheada apresentou melhor potencial de armazenamento do que a erva-mate socada. A condição com 1kPa de O2 manteve a erva-mate mais verde, maior teor de clorofilas e compostos fenólicos totais após 9 meses de armazenamento. A pressão parcial de CO2, independente do nível utilizado, mantém a coloração da erva-mate mais verde, maior teor de clorofilas e compostos fenólicos totais nas ervas provenientes dos dois locais de cultivo.

The aim of this study was to evaluate the effect of controlled atmosphere in the change of color, chlorophyll degradation and phenolic compounds concentration in yerba maté thickly ground (“cancheada”) and thinly milled (“socada”). Yerba maté samples from the towns of Arvorezinha (RS - Brazil) and São Mateus do Sul (PR - Brazil) were stored in four levels of oxygen (1, 3, 6 and 20.9kPa of O2) and four levels of carbon dioxide (0, 3, 6 and 18kPa of CO2) and then were analyzed, after nine months of storage. According to the results, the O2 partial pressure reduction decreased the loss of green coloration, kept a higher content of chlorophylls and of total phenolic compounds. In relation to the different levels of CO2, a response as remarkable as O2 was not observed. The yerba maté that was thickly ground (“cancheada”) presented a better storage potential than the one thinly milled (“socada”) in the storage with O2 and with CO2. The 1kPa of O2 condition kept the yerba maté greener and with a higher content of chlorophylls and of total phenolic compounds after nine months of storage. The CO2 partial pressure kept the yerba maté coloration greener and with a higher content of chlorophylls and of total phenolic compounds, regardless of the level used, in the maté from both cultivation areas.