The food-processing industry has made large investments in processing facilities relying mostly on conventional thermal processing technologies with well-established reliability and efficacy. Replacing them with one of the novel alternatives recently developed is a decision that must be carefully approached. Among them, high-pressure processing (HPP), at room or refrigerated temperature, is now a wellestablished option experiencing worldwide commercial growth. Surveys have shown an excellent consumer acceptance of HPP technology. For financial feasibility reasons, HPP treatments must be kept short, a challenge that can be met by some of the alternatives here reviewed such as the use of the hurdle technology concept. Although HPP technology is limited to pasteurization treatments, the combination of high pressure and high temperature used in pressureassisted thermal processing (PATP) can be used to sterilize foods. An analysis of alternatives to achieve the inactivation of bacterial spores at the lowest temperature possible highlights the need for additional research on the use of germinants. Because of incomplete research, PATP presents several implementation challenges, including the modeling of food temperature, the determination of inactivation kinetics particularly for bacterial spores, and the prediction of chemical changes including the potential formation of toxic compounds.

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The combined effect of relative humidity (RH) and temperature on O2 and CO2 permeability and selectivity (CO2 to O2 permeability ratio) of a wheat gluten film was evaluated using response surface methodology. Studied ranges of RH and temperature were 0−100% and 3−45 °C, respectively. CO2 and O2 permeabilities ranged from 88 to 55 580 and from 77 to 1970 amol m-1 s-1 Pa-1, respectively. RH had an exponential effect on the CO2 and O2 permeabilities and selectivities of wheat gluten film. The effect of temperature appeared to be less pronounced in comparison with that of RH. High selectivity values (28 at 24 °C and 100% RH) of wheat gluten films would be very advantageous for fresh fruit and vegetable preservation under modified atmospheres. Keywords: Wheat gluten films; edible films; gas permeability; selectivity

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Apple juice was pasteurized by an ultra‐high temperature treatment (UHT) at 115, 125 and 135C for 3 and 5 s, and compared with a high‐voltage pulsed electric field treatment (PEF) at ranges between 33 and 42 kV/cm with frequencies of 150, 200, 250 and 300 pulses per second (pps). Enzyme inactivation and physicochemical properties of the treated juices were compared using a nontreated sample as control. The UHT treatment was more efficient in enzyme inactivation, reducing 95% the residual activity of polyphenoloxidase at the maximum temperature and time. However, a PEF treatment at 38.5 kV/cm and 300 pps combined with a temperature of 50C achieved a 70% reduction of residual PFO activity. In terms of quality characteristics as a function of physicochemical properties, color, pH, acidity and soluble solids were all less affected by PEF than by UHT when compared with the untreated juice. PRACTICAL APPLICATIONS Apple juice is a popular beverage worldwide and it is consumed nearly as much as orange juice. Consumers prefer fresh‐squeezed fruit juices with high nutrient value and fresh‐like sensory attributes. Enzymatic browning negatively impacts appearance, nutritive value and flavor of fruit juices. The use of ultra‐high temperature processing is efficient in microbial control, as well as in enzyme inactivation. Any thermal processing may, however, decrease the overall quality of the treated juices. Pulsed electric field processing provides a potential alternative to thermal pasteurization of fruit juices.