These days, food can be kept a lot longer than in the past. But techniques such as pasteurisation and sterilisation also affect the quality of the products. The nutritional quality suffers, the product has less aroma and the flavour and smell of the food sometimes deteriorate. New, milder preservation techniques go a long way to preventing this loss of quality. Wageningen UR Food & Biobased Research has joined forces with a group of Dutch companies in the food industry to explore the application of these techniques.
Credit: Wageningen UR
Three techniques The research focuses on three promising techniques. High pressure processing is an alternative for packaged foods that are currently pasteurised or sterilised. Exposing the products to a pressure of up to 1,000 MPa disables micro-organisms and enzymes without affecting the flavour. The industry has high expectations of pulsed electric field processing for liquid products such as fruit juice, milk, yoghurt and soup. This technique involves treating the products with high voltage pulses. It also lengthens the storage life with no appreciable loss of quality.
The third technique that the consortium is examining is cold plasma. Cold gases (plasmas) with an electrical charge are used to disinfect the surface of food packaging. Here too, the product is expected to suffer minimal damage.
Pulsed electric field processing was recently in the spotlight when Hoogesteger, market leader in fresh fruit juices and smoothies, was nominated for the Food Valley Award. Hoogesteger co-designed the Fresh Micro Pulse, a method whereby ‘PEF’ is used to deactivate micro-organisms at low temperatures.
Agro&food top sector The programme (provisionally dubbed ‘Mild preservation of food products’) is one of the research projects currently being carried out within the Agro&food top sector. Food & Biobased Research is working on the programme together with Struik Foods Europe, Hoogesteger, IXL Nederland, OMVE, Stork Food & Dairy Systems and TNO.
The three mild preservation techniques have another important advantage: they are mild on the purse strings for companies in the food industry. The techniques described above require less energy per kilogram of treated product, because they work at lower temperatures. Bridging the knowledge gap The research programme follows on from a previous European project conducted at 37 knowledge institutes and companies, and headed by Food & Biobased Research. Although this previous project, NovelQ, laid a firm scientific basis, there is still uncertainty about the precise factors that affect the final result of preservation techniques. It is hoped that this new research and innovation programme will bridge the knowledge gap so that companies will know exactly which technique works best with their products under which conditions. Once this knowledge gap has been bridged, there will be room on the shelves for products with a longer shelf life, a better flavour and (possibly) higher nutritional value.