QUALITY OF CUSTARD APPLE (ANNONA SQUAMOSAL L.) IN RELATION TO PACKAGING AND STORAGE PERIOD

Abstract

This work aimed to evaluate the postharvest quality of custard apple (Annona squamosa L.) fruits submitted to different packaging under refrigerated storage. Fruits were unpacked (control), individually packed in polyvinylchloride (PVC) film, or packed in expanded polystyrene trays enveloped in PVC film, and tested during five periods of storage (0, 4, 8, 12, and 16 days) at 10°C. Data of mass loss, pulp hardness, soluble solids (SS), titratable acidity (TA), pH, vitamin C, and water activity (WA) were recorded at harvest and every 4 days over the storage period. Custard apple fruits stored at 10°C and packed in PVC film had reduced mass loss. The modified atmosphere packaging also resulted in decreased loss of firmness, providing about a 12 day postharvest life. Soluble solids and total titratable acidity concentra- tions did not increase significantly during storage. All fruits presented reduction of water activity (WA) during the storage period. The use of packaging films significantly reduced weight loss, preserved firmness and color of fruit. The modified atmosphere allowed for a shelf-life of 12 days at 10°C. Brazil plays a very important role in the world production and consumption of tropical fruits. Among these are fruits of the Annonaceae family. This family includes around 120 genera and 200 species, encompassing a group of fruit crops of economical importance - sour soup (Annona muricata L.), custard apple (Annona squamosa L.), cherimoya (Annona cherimola Mill.), and atemoya (Annona cherimola × A. squamosa L.) - in countries such as Chile, Australia, and Brazil. The specie Annona squamosa L. produces delicate fruits with much appreciated taste. Custard apple fruits reach high prices and are placed in the European and North American markets as an exotic fruit. The northeast region of Brazil has perfect conditions for cultivation of a diverse variety of fruit species that can help in its social-economic development. However, the development of post-harvest fruit conservation technologies, despite some evolution in the last years, is still rare or non-existent for some fruits. It is apparent that there is a growing demand in the internal and external markets for custard apple fruits. This increasing demand has stimulated fruit growers and companies to request researchers to develop methodologies that can favor higher production and better fruit quality. The large interest from consumers and the food industries for frozen pulp justifies the inclusion of custard apple among the Brazilian tropical fruits of excellent commercial value. Inadequate handling and storage of delicate products, lack of refrigeration and inappropriate installations for processing can lead to physical, nutritional and quality losses. Therefore, post-harvest knowledge and awareness of the available technologies is of vital importance for the maintenance of fruit quality. Processes for fruit conservation became very important to increase the market value of products. In general, post-harvest life span of Annona fruits is limited by physiological deterioration, caused by fruit over ripening, loss of pulp firmness, and darkening of the skin caused by the development of pathogens (Silva et al., 2009). Being a climacteric fruit, the loss of flesh consistency and skin darkening are associated with rapid elevation of the ethylene synthesis at the beginning of the ripening process (Martinez et al., 1993).