HOT WATER AS AN ALTERNATIVE POSTHARVEST TREATMENT IN Citrus reticulata VAR. MURCOTT AND W-MURCOTT

MORALES, LUISINA; MARGARIT, EZQUIEL; MONTECCHIARINI, MARINA; RIVADENEIRA, FERNANDA; BELLO, FERNANDO; GOLLÁN, AGUSTÍN; VÁZQUEZ, DANIEL; PODESTÁ, FLORENCIO; TRIPODI, KARINA E. J.

Congreso; Congreso de SAIB; 2020

SAIB

Citrus commercialization is an important resource of the regional economies in our country. The time passed by until the fruitreach most of the export markets may seriously affect their quality and health. To overcome this, fruits are kept at lowtemperatures. However, citruses are especially sensitive to cold, and conditioning treatments are usually carried out to preservetheir desirable organoleptic features. This work aims to compare the performance of two mandarin varieties: Murcott(traditionally employed in our country) and W-Murcot (recently incorporated into local production), under thermal treatmentwith hot water (HT). The internal quality parameters, carbohydrate metabolism enzymes, and fatty acids were examined in thefruit’s flavedo of both varieties. Treated fruits maintained their parameters of internal quality in comparison with control ones,meaning that they do not decay during the postharvest period. Moreover, they achieved a lower dehydration than control fruit,although this effect was less noticeable in W-Murcott, that showed in general, a greater dehydration. The enzymatic activitiesof adenosine triphosphate-dependent phosphofructokinase (ATP-PFK), pyrophosphate-dependent phosphofructokinase (PPiPFK) and pyruvate kinase (PK), varied according to the storage period and not due to exposure to HT, although the differencein ATP-PFK/PPi-PFK activities between varieties was remarkable. In Murcott mandarins, there was a significant decrease inoleic acid in treated samples after 9 days of storage, compared to non-treated fruits. In contrast, the W-Murcott variety onlyshowed differences regarding storage time, and not due to the treatment. In conclusion, varieties responded differently to HT,mainly in terms of dehydration during the postharvest period. Other changes that probably involve varietal diversity in carbonpartitioning are connected with the storage period and not with HT.