Conductive frying of meat: current state and prospects

Abstract

One of the major economic challenges for the countries of the former Soviet Union, including Ukraine and Kazakhstan, is the low energy efficiency of technological processes. Energy efficiency is one of the key integral indicators of the state and development of the economy, the fuel and energy sector, and energy management systems. It refers to the efficient use of fuel and energy resources at various stages of a product’s life cycle: design and development of technical requirements, product development, manufacturing, quality control, testing and inspection, operation, and disposal. Energy efficiency is sometimes referred to as the “fifth” fuel because using energy more efficiently means using less energy to achieve the same level of energy supply in technological processes. The food industry is a vital sector of the economies of Ukraine and Kazakhstan, and it faces the same challenges. However, between 2007 and 2024, the energy efficiency of the food industry increased by 6.5% – from 38.4% to 44.9% of the EU level – due to the implementation of new production methods, modern equipment, and improved quality control. Based on this, the minimum potential for energy savings in the food industry can be estimated at 55.1% of current energy consumption. Frying meat products is one of the most widespread methods of thermal processing. This process is characterized by significant mass loss (up to 11–35%) and high specific heat consumption (up to 1000–1300 kJ/kg). The energy efficiency of this process largely depends on the method of heat supply and the design features of the equipment and is generally low. The process requires maintaining high-temperature conditions (423–473 K), and the equipment used is subjected to considerable thermal stress on the heating surfaces (up to 45 kW/m²). An analysis of the development of conductive frying equipment and the scientific literature on the topic shows that issues related to energy efficiency of the process and its equipment, as well as yield improvement and product safety, have not received sufficient attention. Conductive frying of meat is also limited by resource constraints. Only specific cuts of carcasses from slaughtered animals are suitable for frying: tenderloin, loin, sirloin, and top and inside round cuts of the hindquarter. These parts constitute no more than 10–20% of the total carcass weight of cattle. These cuts are characterized by a thin, delicate network of connective tissue composed mainly of collagen fibers. Other parts of the carcass (neck, hindquarter, shoulder) contain significantly more connective tissue and are therefore unsuitable for conductive frying. Instead, they are used to produce minced or chopped semi-finished products. Each year, the cattle and pig population in Ukraine and Kazakhstan decreases by an average of 4.5%, significantly reducing the resource base for conductive frying processes. This negatively affects the cost of semi-finished products. To mitigate this, the governments of Ukraine and Kazakhstan import meat raw materials from various countries (Brazil, Poland, Germany, etc.). As a rule, the cost of imported raw materials, including customs duties, is lower than that of domestic products. However, the quality of such imported meat is often low, which negatively impacts the energy efficiency of thermal processing. Moreover, the presence of rabies virus and traces of genetically modified organisms (GMOs) in imported meat cannot be ruled out due to the use of GMO-based feeds. This monograph addresses and proposes solutions to the pressing scientific and applied problems of low energy efficiency, low product yield, and insufficient resource base in the process of conductive meat frying. The monograph is intended for a wide audience, including academic staff, researchers, higher education students, and practitioners in the food production industry, including the restaurant sector. The authors express their sincere gratitude to the reviewers of the monograph and to their colleagues – academics and researchers – who provided valuable critical feedback on its content.