Reaction Kinetics at High Pressure and Temperature: Effects on Milk Flavor Volatiles and on Chemical Compounds with Nutritional and Safety Importance in Several Foods

Abstract

Consumers demand, in addition to excellent eating quality, high standards of safety and nutrition in ready-to-eat food. This requires a continuous improvement in conventional processing technologies and the development of new alternatives. Prevailing technologies such as thermal processing can cause extensive and undesirable chemical changes in food composition while minimal processing strategies cannot eliminate all microbial pathogens. This review focuses on pressure-assisted thermal processing, a new alternative for shelf-stable foods. Its implementation requires an analysis of reaction kinetics at high pressure and elevated temperature. Acceleration of the inactivation of bacterial spores by the synergistic effect of pressure and temperature is expected to allow processing at lower temperature, shorter process time, or a combination of both. Therefore, thermal degradation of quality is expected to be lower than that of conventional thermal processes. However, few studies have focused on the effect of the conditions required for the inactivation of bacterial spores on the kinetics of chemical reactions degrading food quality, particularly at the high temperatures required for the processing of low-acid foods.

High-Pressure Processing Technologies for the Pasteurization and Sterilization of Foods

“…Although pressure levels in the range of 400-800 MPa inactivates the vegetative forms of pathogenic and spoilage bacteria (San Martin et al 2002;Smelt et al 2002;Velazquez et al 2002Velazquez et al , 2005aMoermann 2005;Torres and Velazquez 2008;Valdez-Fragoso et al 2010), the inactivation of bacterial spores by pressure alone is not possible. Therefore, current HPP products on the market rely on refrigeration, reduced water activity and/or low pH to prevent bacterial spore outgrowth.…”

“…Immediately available to commercialize PATP technology, is alternative (c) in Table 2, i.e., temperatures above 100°C to inactivate bacterial spores in a reasonably short time. The limitation of this alternative is the need for research on reaction kinetics in the pressure and temperature range required for this alternative, a severe limitation at this time (Ramírez and Torres 2009;Torres et al 2009b;Martínez Monteagudo et al 2011;Valdez-Fragoso et al 2010) when compared to the large availability of data on the inactivation of bacterial spores (Reddy et al 2003;Margosch et al 2004Margosch et al , 2006aRajan et al 2006;Ahn et al 2007a,b;Paredes-Sabja et al 2007;Naim et al 2008;Zhu et al 2008;Juliano et al 2009;Ratphitagsanti et al 2009). …”

High Pressure Treatment Effect on Physicochemical and Nutritional Properties of Fluid Foods During Storage: A Review

“…High pressure (HP) processing has been used to achieve this goal without affecting food quality. Although the effectiveness of these treatments for making food safe has been known for some time, it is only now that it has become possible to develop this technology and apply it on a large scale in order to bring HP‐processed foods to market (Heinz and Buckow 2009; Valdez‐Fragoso and others 2011). HP treatment is based on two fundamental principles: the Le Chatelier principle, which proposes that pressure favors all structural reactions and changes that involve a decrease in volume; and the isostatic principle, which proposes that the distribution of pressure is proportional in all parts of a foodstuff irrespective of its shape and size (Heremans 2002; Valdez‐Fragoso and others 2011).…”

Benefits and limitations of food processing by high-pressure technologies: effects on functional compounds and abiotic contaminants Beneficios y limitaciones del procesamiento de alimentos por tecnologías de alta presión: efectos en componentes funcionales y contaminantes abióticos

“…The greater the magnitude of V a (positive or negative) the higher the sensitivity of a chemical reaction to pressure while reactions with V a ¼ 0 are pressure independent (Mussa & Ramaswamy, 1997;Valdez-Fragoso et al, 2011). The corresponding pressure effects on E a values are a decrease, no change or an increase if V a 5 0, ¼ 0, or 40, respectively.…”