Effect of thermal and high-pressure processing on the nutritional value and quality attributes of a nectarine purée with industrial origin during the refrigerated storage

Abstract

The application of hydrostatic high pressure on an industrial line of nectarine (Prunus persica L.) purées was assessed in comparison with the traditional thermal treatment of pasteurization. Changes after thermal processing (85 °C, 5 min) and after high-pressure processing (HPP: 450 or 600 MPa for 5 or 10 min) and during the refrigerated storage (60 d) of an industrially produced nectarine purée were evaluated. Conventional heat pasteurization as well as HPP showed similar microorganisms' inactivation and maintained the microbial stability of purées until the end of the refrigerated storage (60 d). In general, thermally treated purée and HP-treated purée at 600 MPa showed more intense color changes after processing than the other treatment. In addition, thermally treated purée showed more intense color changes during storage than HPP. The highest carotenoids extractability was found in those purées treated at the lowest high-pressure-treatment intensity and holding time (450 MPa/5 min), but at the end of the storage (day 60), no differences in individual or total carotenoid levels were found between the purées. HPP at 600 MPa/10 min showed the highest polyphenols content after the treatment and during the storage. At day 0, significantly higher values were found of total antioxidant activity in purée HP-treated at 450 MPa/10 min than in untreated purée; while at the end of the storage, HP-treated purée at 600 MPa/10 min had the highest antioxidant activity. Hydrostatic high-pressure application in the industrial line of nectarine purée presented some advantages compared to the thermal treatment; however, some of the changes found were lessen during the storage period. In addition, more studies need to be carried out for HP-treatment intensity optimization.