Amazon natural indicators of acid-base: methods and possibilities

Abstract

This work aims to evaluate Amazon fruits potential to natural indicators of acid-base to chemistry teaching and optimize pigment extraction with proven efficiency. Methodology was experimental research with qualitative and quantitative approach. Extraction of the tucumã (Astrocaryum aculeatum), bacaba (Oenocarpus bacaba mart.), açaí (Euterpe precatoria), bacuri (Garcinia madruno), piquiá (Caryocar villosum) and buriti (Mauritia flexuosa) pigments was realize by different extraction techniques. Reversibilidade assay of the chemical balance. Açaí, bacaba and tucumã extracts presented variations of colorations when added in solutions acid, basic and neutral, and showed considerable reversibility. The samples of the açaí and tucumã in cold maceration, and bacaba fruit and hot maceration show more appropriate method for the pigment’s extraction. These results suggest that açaí, bacaba and tucumã fruits can be used to acid-base natural indicator model, be through the extract or paper indicator, with viable alternative to conventional teaching chemistry methods.