Applications of ultrasound in food technology: Processing, preservation and extraction

http://irep.iium.edu.my/28632/4/Santanu_J_Food_Eng%2D2013.pdf

Techniques for extraction of bioactive compounds from plant materials: A review

Bacteriocin-based Strategies for Food Biopreservation

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骨髄異形成症候群のgenome-wide analysis

Ultrasound has attracted considerable interest in food science and technology due to its promising effects in food processing and preservation. As one of the advanced food technologies it can be applied to develop gentle but targeted processes to improve the quality and safety of processed foods and offers the potential for improving existing processes as well as for developing new process options. Some applications like cutting or sieving have already found their place as state of the art technologies. Others are currently considered as possible candidates for industrial application. In this review selected and potential applications of ultrasound mainly in the field of food preservation and product modification are discussed.

Applications and potential of ultrasonics in food processing

In excess of a critical transmembrane potential ΔϕM of −1 V produced by high intensity pulsed electric fields a rapid electrical breakdown and local conformational changes of cell membranes occur which result in a drastic increase in permeability and an equilibration of the electrochemical and electrical potential differences of the cell plasma and the extracellular medium. As irreverible membrane permeabilization impairs most vital physiological control systems, high intensity pulsed electric fields may be applied as a highly effective process for the microbial decontamination of liquid foods. The efficiency of the treatment is largely influenced by the inherent properties of the foods and of the spoiling microorganisms. In addition a number of technical limitations have to be considered. In this review an approach is presented which reduces the diversity of parameters that affect microbial inactivation during pulsed power treatment. In particular, the required total specific energy input is discussed.

Preservation of liquid foods by high intensity pulsed electric fields-basic concepts for process design

Preservation of liquid foods by high intensity pulsed electric fields (PEF) is an interesting alternative to traditional techniques like thermal pasteurization. Based on the underlying mechanism of action, in this paper the crucial process parameters electrical field strength, total pulse energy input and treatment temperature were investigated experimentally. Inactivation studies were performed with three bacteria ( E. coli, Bacillus megaterium, Listeria innocua ) and one yeast ( Saccharomyces cerevisiae ). Stainless steel and carbon electrodes have been tested to investigate their applicability as electrode material. Simulating the influence of cell size and orientation as well as the presence of agglomerations or insulating particles indicated that the applied field strength has to be increased above the critical one to achieve product safety. It was found that temperatures higher than 40 °C can strongly increase the lethality of the PEF process. In this way also small cells like Listeria are easily affected by pulsed fields even at a field strength as low as 16 kV cm −1 . In addition, heating of the product prior to PEF has the advantage that most of the required process energy can be recovered using heat exchangers. Exemplary, such a process is analyzed by an enthalpy balance.

High intensity pulsed electric fields applied for food preservation

Food production is among the highest human environmental impacting activities. Agriculture itself accounts for 70–85 % of the water footprint and 30 % of world greenhouse gas emissions (2.5 times more than global transport). Food production’s projected increase in 70 % by 2050 highlights the importance of environmental impacts connected with meat production. The production of various meat substitutes (plant-based, mycoprotein-based, dairy-based, and animal-based substitutes) aims to reduce the environmental impact caused by livestock. This article outlined the comparative analysis of meat substitutes’ environmental performance in order to estimate the most promising options. The study considered “cradle-to-plate” meal life cycle with the application of ReCiPe and IMPACT 2002+ methods. Inventory was based on literature and field data. Functional unit (FU) was 1 kg of a ready-to-eat meal at a consumer. The study evaluated alternative FU (the equivalent of 3.75 MJ energy content of fried chicken lean meat and 0.3 kg of digested dry matter protein content) as a part of sensitivity analysis. Results showed the highest impacts for lab-grown meat and mycoprotein-based analogues (high demand for energy for medium cultivation), medium impacts for chicken (local feed), and dairy-based and gluten-based meat substitutes, and the lowest impact for insect-based and soy meal-based substitutes (by-products allocated). Alternative FU confirmed the worst performance of lab-grown and mycoprotein-based analogues. The best performing products were insect-based and soy meal-based substitutes and chicken. The other substitutes had medium level impacts. The results were very sensitive to the changes of FU. Midpoint impact category results were the same order of magnitude as a previously published work, although wide ranges of possible results and system boundaries made the comparison with literature data not reliable. The results of the comparison were highly dependable on selected FU. Therefore, the proposed comparison with different integrative FU indicated the lowest impact of soy meal-based and insect-based substitutes (with given technology level development). Insect-based meat substitute has a potential to be more sustainable with the use of more advanced cultivation and processing techniques. The same is applicable to lab-grown meat and in a minor degree to gluten, dairy, and mycoprotein-based substitutes.

Volker Heinz

Papers

Applications and potential of ultrasonics in food processing

Preservation of liquid foods by high intensity pulsed electric fields-basic concepts for process design

High intensity pulsed electric fields applied for food preservation

Meat alternatives: life cycle assessment of most known meat substitutes

High pressure application for food biopolymers.