Sensorial and Biochemical Parameters of Avocado Product with Addition of α-Tocopherol and Ascorbic Acid

Erica      R. Daiuto; Rogerio      L. Vieites; Lidia      R. de Carvalho; Maria      A. Tremocoldi

Abstract

Commercialization of processed avocado is difficult due to darkening of the pulp and sensorial alterations during the storage. The objective of this research was to verify the sensorial parameters, along with polyphenol oxidase and peroxidase activities in an avocado product with added α-tocopherol and ascorbic acid and stored at low temperature. Samples of products were wrapped in polyethylene and polyethylene plus nylon packing, with and without being vacuum sealed. They were submitted to low temperature treatments: refrigeration, slow and fast freezing. Evaluations were done on days 0, 1, 3, 5 and 7 for the refrigerated treatment (± 4 ºC) and days 0, 7, 30, 60 and 90 for the samples submitted to the slow and fast freezing. Enzyme activities decreased in the product (24.55 mM of catechol/gram of fresh mass) in relation to the avocado pulp (58.31 mM of catechol/gram of fresh mass of sample). They were almost unaltered during low temperature storage, but were slightly lower in the vacuum packed samples. The ascorbic acid concentration was not enough to inhibit the enzyme activity totally. Sensorial analysis showed that the addition of ascorbic acid allowed the conservation of product refrigerated in polyethylene bags without altering its sensorial characteristics. The α-tocopherol addition proved to be unviable as it did not conserve the product’s flavor.

Keywords: Persea americana mill, avocado., vitamin C, frozen foods, α-Tocopherol, enzymes, fatty acids, polyethylene bags, sensorial characteristic, storage.