The demand for proteins is rising and alternatives to meat proteins are necessary since animal husbandry is expensive and intensive to the environment. Plant proteins appear as an alternative; however, their techno-functional properties need improvement. High-pressure processing (HPP) is a non-thermal technology that has several applications including the modification of proteins. The application of pressure allows modifying proteins' structure hence allowing to change several of their properties, such as hydration, hydrophobicity, and hydrophilicity. These properties may influence the solubility of proteins and their ability to stabilize emulsions or foams, create aggregates or gels, and their general role in stability and texture of food commodities. Commonly HPP decreases the proteins' solubility yet increasing their surface hydrophobicity exposing sulfhydryl groups, which promotes aggregation or gelation or enhance their ability to stabilize emulsions/foams. However, these effects are not verifiable for all the proteins and are immensely dependent on the type and concentration of the protein, environmental conditions (pH, ionic strength, and co-solutes), and HPP conditions. This review collects and critically discusses the available information on how HPP affects the structure of plant proteins and how their techno-functional properties can be tailored using this approach.

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(2015) Preservation under pressure (hyperbaric storage) at 25°C, 30°C and 37°C of a highly perishable dairy food and comparison with refrigeration, CyTA -Journal of Food, 13:3, 321-328, DOI: 10.1080/19476337.2014 To link to this article: https://doi.org/10. 1080/19476337.2014 Hyperbaric storage (HS) under mild pressure of requeijão, a traditional Portuguese whey cheese, as a case study of a highly perishable dairy food, was evaluated as a possible energy costless alternative to refrigeration. Whey cheese was stored for 4 and 8 hours, at different pressure levels (0.1, 100 and 150 MPa) and temperatures (25°C, 30°C and 37°C), and the results were compared with refrigeration (4°C). Microbial analyses showed that storage for 4 hours at 100 MPa was able to maintain microbial counts similar to refrigeration and initial load, ≈3 Log 10 CFU/g, at all tested temperatures. By increasing the pressure to 150 MPa and the storage time to 8 hours, microbial loads were reduced to undetectable counts, with the exception for total aerobic mesophiles that were reduced to about ≈1 Log unit. HS in general maintained pH, water activity and lipid oxidation values, at levels similar to that in refrigeration.Keywords: food preservation; high pressure; hyperbaric storage; refrigeration; whey cheeseEl almacenamiento hiperbárico bajo una presión suave del requeijão, un queso de suero típico en Portugal, como caso de estudio de un producto lácteo altamente perecedero, fue evaluado como una alternativa sin ningún coste energético a la refrigeración. El queso de suero fue almacenado durante 4 y 8 horas, a diferentes niveles de presión (0,1; 100; y 150 MPa) y temperaturas (25, 30, y 37°C). Los resultados fueron comparados con la refrigeración (4°C). Los análisis microbianos mostraron que el almacenamiento de 4 horas a 100 MPa era capaz de mantener los recuentos microbianos similares a los de la refrigeración y carga inicial, ≈3 Log 10 CFU/g, para todas las temperaturas examinadas. Mediante el incremento de la presión a 150 MPa y el tiempo de almacenamiento a 8 horas, la carga microbiana fue reducida a recuentos indetectables, excepto el total de aerobios mesófilos que fue reducido alrededor de ≈1 unidad Log. El almacenamiento hiperbárico en general conservó pH, actividad del agua y valores de oxidación lipídica, a niveles similares a la refrigeración.Palabras clave: conservación alimentos; alta presión; almacenamiento hiperbárico; refrigeración; queso de suero

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Sargassum muticum is an important source of bioactive polysaccharides; hence, high hydrostatic pressure (HHP) was used to improve their extraction efficiency. Response surface methodology and a Box‐Behnken full factorial design were employed to assess and optimize the effects of extraction conditions on the yield, total sugars, total sulfated sugars and antioxidant activity of S. muticum extracts. The extraction yield ranged between 32 and 40.4% independently of the extraction conditions or seaweed solid/liquid ratio resulting in average increases of 3.6 to 4.8‐fold for total sugars and sulfated sugars, as compared to conventional extraction. Extracts displayed improved antioxidant activities, yet maximum values were achieved under different optimum conditions of HHP processing, for example, 5–5.5 min, 300 MPa and 1 g of dry seaweed for yield. In conclusion, the optimal HHP technology conditions described in this paper enables to obtain enriched bioactive polysaccharide S. muticum extracts. Practical Applications High hydrostatic pressure (HHP) is a suitable method used to improve the extraction of natural ingredients with added value both in terms of nutritional value as in biological properties from different natural sources. In this study it was intended to evaluate the potential and the effectiveness of HHP to obtain extracts concentrated in bioactive polysaccharides from the brown seaweed Sargassum muticum. A new and possible strategy to valorize this invasive brown seaweed rich in sulfated polysaccharides with several health benefits associated. The main results have demonstrated that HHP increased extractability (higher extraction yields) and bioactivity from the seaweed S. muticum, providing extracts with higher content in polysaccharides which can be used as ingredients to develop novel functional foods.