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High pressure in the food industry, as a new non-thermal method, is applied in many phases of food processing. This new non-thermal technology was developed in the 1990s. The main advantages of high-pressure processing are in the short time of processing which is between a few seconds and 30 minutes. Processing of solid or liquid food products with or without packaginghappens in the temperature interval 5 – 90 °C, and pressures 50 – 1000 MPa. The driving pressure is distributed uniformly through the whole product independently of its quantity and shape. These processing characteristics combined with improved food microbiological safety, less energy expenditure, low concentration of waste products and longer shelf life make high-pressure processing a very promising novel food technology. Combined with lower cost of treatment (but unfortunately higher initial cost of equipment) compared to traditional processing technologies, it is also economically profitable. The main purpose of such treated food products are in preservation of sensory, nutritive and textural properties. As the temperature increase is very low, there are no significant changes in sensory properties, in contrast to conventional thermal processing (sterilization, pasteurization). However, with the combination of heating or cooling and high pressure, modification of existing and creation of new food products is possible. Today, high pressure is used for the treatment of meat products (inactivation of microorganisms), freezing and defrosting of foodstuffs, production of fruit juices (pasteurization), processing of oysters, modificationof milk characteristics (foaming) etc. The main purpose of this work is to present the working principle and application of high pressure in the food industry.

An innovative ultrasound-assisted extraction (UAE) is the rapid non-thermal extraction technique, which in comparison to conventional extraction (CE), offers high reproducibility in a short time with simplified manipulation, reduced solvent consumption and lower energy. Optimization of ultrasonic conditions was conducted for devices with nominal output power of 100 and 400 W, including the influence of geometrical parameters of probes regarding ultrasound-assisted extraction. The results showed that the optimal parameters for extraction of total phenols and rosmarinic acid as a dominant compound in sage extracts were as follows: solvent: 30% ethanol, extraction duration of 11 minutes, and ultrasonic device output power of 400 W. The antioxidant capacity of the obtained extract correlated with the concentration of total phenols and flavonoids, and among individual phenols the rosmarinic acid contributed the most to the antioxidant capacity. The achieved results and statistical analysis (p ≤ 0.05) have shown how UAE resulted in shorter extraction time, and increased extraction capacity of phenolic compounds by using solvents with a less amount of organic phase. [ABSTRACT FROM AUTHOR]

Innovative and eco-friendly food technologies in practical usage today like Ultrasound (US) and High Hydrostatic Pressures (HHP) are feasible to adequately maintain various food properties while processed, such as texture, sensorial and organoleptic characteristics, and microbiological issues as well. Benchmarked attribute of the mentioned approach lies in the ability of US and HHP to control and withhold both temperature and treatment duration. While temperature could be controlled within room ambient, treatment time is mostly below 30 minutes. US and HHP treatment were performed as separate treatments in order to obtain better homogenization. Goat milk was exposed to ultrasonic propagation up to 100 W of nominal power and high pressures up to 600 MPa. Maximum treatment time was 9 minutes. Ultrasonic homogenization indicates enhanced homogeneity of fat globules while high pressure process parameters have a significant influence on the observed mean particle diameter (fat globules). Improved stability and quality of emulsions (goat milk) was obtained by both applied processes. Statistical analysis indicated the influence of process parameters on fat globule size distribution between 0.3 - 4 µm and variance lower than 0.6. [ABSTRACT FROM AUTHOR]