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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.

The stability after hydrostatic high pressure (HHP) (600 MPa/8 min/ 10 • C) and 180 days of storage at 4 and 20 • C was evaluated on Iberian drycured pork sausages (chorizo) packaged sliced or as half-pieces from pigs raised outdoors. Microbiological, physical-chemical, oxidative, and sensory changes were analyzed. The evolution of mesophilic aerobic and molds and yeasts counts was different in the half and sliced packaged pork sausages after processing and during storage. Sliced and half-packaged pork sausages had instrumental color stability after HHP and during storage. TBA-RS values were quite stable in both products. Protein oxidation values of pork sausage in half-products were increased by at 20 • C. In sliced pork sausage, both HPP and 20 • C storage favored the development of protein oxidation at the end of storage. In the sensory analysis, the sliced product developed more rancidity than the half-pieces during the storage. Therefore, the storage temperature has great importance for the preservation of dry-cured pork sausages, the increases of protein oxidation, and rancidity could reduce the shelf-life at these conditions. The presentation of the product is also relevant when HHP is applied, and this would also compromise the stability of the product when it is stored at room temperature. Practical Application: Chorizo is a traditional dry-fermented pork sausage that is generally considered to be microbiologically safe. However, the initial contamination of the raw materials, and some processes, such as the slicing or packaging, can compromise the safety of these products. Additionally, packaged dry-cured sausages require long shelf-life, and although they are normally stored at refrigeration temperature; sometimes, they are preserved at room temperature. The application of hydrostatic high pressure could increase the safety of dry-cured meat products even when they are stored at room temperature. Initial characteristics of each type of pork sausage could determine their technological behavior during processing or during storage under different conditions.