Increasing the Efficiency of Fryers
Frying invariably involves the evaporation of significant quantities of water from the food product. The process is also complex to control due to the variability of raw materials, the large number of parameters involved and the interactions between these parameters. Good control of the process is, however, important as it determines not only the final product quality attributes but also has a significant influence on energy consumption.
Investment in energy-efficient technologies can make a significant contribution towards reducing production costs. Energy-efficient technologies can also offer additional benefits, such as quality improvement, and improved environmental performance in terms of reductions in CO2 emissions.
Arnaud Jansse, Applications Engineer (Food Technologist), tna solutions says their fryers incorporate several design features aimed at improving the sustainability for their customers’ frying processes. “Alongside insulated fryer hoods and filter housing, we offer indirect heating systems (via steam or thermal oil heat exchangers), which are generally considered more energy efficient than direct heating systems. That said, steam generators, commonly powered by gas burners, aren’t considered the most sustainable option. In the future, however, these systems have the potential to run on green energy sources (e.g. wind or solar power), which will eliminate the need for burning fossil fuels and further reduce emissions,” he explains.
Meanwhile, frying using minimal oil volumes means less energy is required to heat the oil and can therefore reduce energy consumption. In addition, energy recovery systems for frying emissions and blanchers can support the re-use of energy across the entire production line for even greater optimization.
“Looking ahead, we’re currently exploring opportunities to enhance insulation of the oil circulation system piping, as well as the fryer kettle to further minimize heat loss. Alternative energy sources for steam heating systems are also a key focus with opportunities to look for cleaner alternatives, such as electric or hydrogen-powered models,” Jansse points out.
The challenge in making fryers more efficient comes from the process itself, since energy is needed to heat the oil that is used to cook the raw materials. Most frying systems, however, have an open design or structure, which can result in energy loss via heat radiation. This includes the emission of frying vapors into the environment. Additional features such as insulation of the fryer hood can therefore help to save energy by preventing heat and emissions being lost from the fryer. Although, such additions, despite bringing significant benefits, can often introduce design challenges due to additional weight. Equipment manufacturers must therefore seek alternative solutions such as lighter composite building materials or re-designing the hood and lifting system.
In a recent interview, Göran Wadsten, who is a senior advisor for Rosenqvists Food Technologies, told Potato Business about the different strategies a processor might use in order to increase the efficiency of the frying process.
“If you’re going to produce one ton of finished potato chips then you need to add nearly four times as many raw potatoes per hour into the line. So in fact, you need to evaporate almost 3000 liters of water per hour, which would take about 2.5 megawatts of power to accomplish. Of this amount, about 500 kilowatts would be spent on the blancher alone,” he exemplifies.
You can read the rest of this article in the Spring Issue of Potato Business Digital magazine, which you can access by clicking here.