Non-thermal concentration methods for Amazonian fruits
The traditional thermal concentration methods used in the elaboration of concentrated fruit juices remarkably affect the sensory characteristics and nutritional value of final products, especially for highly thermolabile compounds. The present study evaluated the effect of the use of alternative thermal concentration methods, such as cryoconcentration and partial spray drying, on the conservation of the bioactive compounds in asai fruits (Euterpe precatoria) and camu camu (Myrciaria dubia). Each fruit was evaluated using two working temperatures as process variables and two filtration methods of the initial sample for the cryoconcentration method. The results showed that, for the asai juice, there was an increase of more than 500% for the mg L‑1 of cyanidin-3 glucoside with respect to the original sample; a similar result was obtained for the camu camu juice, which, besides being a fruit with one of the highest concentrations of vitamin C worldwide, achieved an increase of more than 300%. The sensory characteristics of the concentrates were not affected, as compared to the adverse effects observed with the traditional thermal concentration methods, resulting in a product that was rich in the compounds of interest with a high sensory quality that can be used in the food industry.
Martínez, A.M., Hernández, M.S. and Fernández-Trujillo, J.P. (2020). Non-thermal concentration methods for Amazonian fruits. Acta Hortic. 1274, 131-136
anthocyanins, juice processing, juice quality, vitamins