The isolated effect of low oxygen and high carbon dioxide on yerba mate quality keeping

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.

Key words Ilex paraguariensis; carotenoids; coloration; polyphenol concentration; storage time