PEF Systems: A Cost-effective Processing Technology
Pulsed Electric Field technology (PEF) enables the development of innovative, cost-effective, and sustainable processing concepts for the manufacturing of French fries, crisps and other potato specialties. PEF treatment is already being applied in the production of French fries on an industrial scale around the world and offers a host of benefits and possibilities.
By Mark de Boevere, managing director Pulsemaster bv
PEF is a non-thermal technology for food processing based on the application of repetitive, short electric field pulses to the food. This creates miniscule holes in membranes of the plant cells, which makes the cells porous and facilitates transport of water and other valuable compounds. This technology induces poration of membranes of potato cells, leading to cell disintegration. A typical PEF system for potato processing consists of a high voltage pulse generator and a treatment chamber through which the potatoes flow in water. In the treatment chamber the high voltage pulses are applied. PEF technology has also been tested and validated for other applications such as fresh fruit juices, tomato processing, olive oil and red-wine making.
In the potato industry, PEF technology results in improved cut quality: a softer texture facilitates French fries cutting. This results in less breakage and shattering, producing longer and thinner French fries, from large potatoes. Improved cut quality gives the French fries a smoother surface, which then reduces oil absorption during frying. French fries are long because the potatoes break less during processing, post cutting. Improved cutting of crisps results in smoother surfaces and less coloration. Crisps processors experience a noticeable improvement in cutting or slicing of potatoes and other vegetables which has a two-fold effect. Firstly, your slicer yield is higher and secondly the slicer blade life is extended. Even important, the improved texture of the potato slices themselves means there is less oil uptake during the cooking process, resulting in a healthier product. Processors can also realize further cost savings by the reduction of blanching requirements in the preparation of the product.
The subsequent reduced oil uptake and water retention leads to crunchier crisps. In potato mash production, pulsed electric field processing evens out the structural variations in potatoes, resulting in a large reduction of the number and size of lumps and a smoother mash for a better bite. New cuts, shapes and French fries and crisps made from different vegetables are among the possibilities. Tough and inconsistent raw materials like sweet potato, turnip and beet root become easily processable with PEF. French fries cutting at optimum product texture results in less breakage and shattering, producing longer and thinner French fries. A French fry cut potato after PEF is much less rigid than an untreated potato.
The complete article is available in our latest Potato Processing International print magazine issue (November/December 2019).