Thermal inactivation studies on toxic seeds from fruits of the Brazilian Central Plain

Abstract

Seeds from endemic Brazilian fruits (Mangaba, Cagaita, Jatoba and Araticum), previously confirmed to be toxic using Artemia salina bioassay were exposed to different temperatures and heating times aiming to test inhibitory effects on toxicity, as a first approach to characterize and identify toxic compounds and their thermal stability. After treatment, water extracts from kernels were filtered and added to Artemia cultures for 24 hours after which the survival of cultures was calculated. The inhibitory effect of temperature on toxicity was significant, whereas toxins from Mangaba and Cagaita were the most labile, showing 90% Artemia survival after heating at 78 °C for 2 minutes and 10 minutes, respectively. The most resistant toxins were those found in Araticum seeds which remained active (0% Artemia survival), even after heating at 160 °C for 12 min. Response surfaces and statistical multivariate analysis showed a significant effect for both temperature and heating time (linear fit) on Cagaita and Mangaba toxicity reduction, while the temperature factor was more significant in Jatoba samples. The results confirm the need to adopt safety procedures during the manufacture of industrialized derivatives for these fruits, in order to minimize toxicity risks after their consumption.