Radiação gama e atmosfera modificada passiva na qualidade de goiabas 'Pedro Sato'

The aim of this study was to evaluate the effect of gamma irradiation associated with modified atmosphere, on postharvest quality of guavas 'Pedro Sato', checking their physicochemical characteristics. Guavas from the region of Vista Alegre do Alto/SP/Brazil, were used. After harvest, the fruits were immediately transported to the Fruit and Vegetables Laboratory of the Agroindustrial Management and Technology Department, Agronomic Sciences College - UNESP - Botucatu / SP, where they were kept at 10 ° C and 90-95% RH in cold storage, for 28 days. The treatments were: control 1 (without package or irradiation), control 2 (polystyrene package-PS) + low density polyethylene package-LDPE and without irradiation) treatment 1 (PS + LDPE and 0.2 kGy), treatment 2 (PS + LDPE and 0.6 kGy) and treatment 3 (PS + LDPE and 1.0 kGy). The analyses were: firmness, soluble solids (SS), titratable acidity (TA) and maturity index. It was used the randomized design with a factorial design 5 x 5 (treatment x time). In the end of this work it was concluded that high doses of irradiation promoted a negative effect on physicochemical characteristics of guava 'Pedro Sato', verifying that only the lowest dose associated with modified atmosphere provided fruits with higher quality and acceptability, due to the higher maturity index and soluble solids obtained.