Catalyst for Catallix

Recent EU legislation (2032/2003) says the use of sodium hypochlorite and chlorine in contact with food will be forbidden in 2006 in all European Union countries.

As both are currently used to kill the pathogens commonly found on fresh foods, alternative methods of fresh food sterilisation need to be sought. One such alternative is a biotechnological process that mimics nature's defence system and is effective against gram negative and gram positive bacteria, moulds and viruses (table 1). The Catallix system, which was perfected by TMI Europe in partnership with Biopole, of Belgium, and the Anvar Innovation Institute in France, is a means of obtaining a continuous supply of pure, natural, clean water that has its own built-in biocidal properties. Easily inserted into a wide range of food or beverage processing lines, the process 'activates' water to give it biocidal and bacteriostatic properties. Essentially, the system draws on an enzymatic reaction to create a natural anti-bacterial agent and, thanks to a new immobilisation technology developed by the company, the enzyme can be used, recycled and used continuously in a biogenerator (figure 1) to give a constant flow of activated water. The aim of the immobilisation is to be able to recover the enzyme and recycle it for a continuous flow production at low cost. The enzyme, a lactoperoxidase, has no antimicrobial activity by itself, but catalyses an oxidation reaction between hydrogen peroxide and thiocyanate ions. The oxidation products are hypothiocyanite ions (OSCN-) and water, and it is the former that is responsible for the destruction and/or inhibition of the bacteria. The Campden & Chorleywood Research Association, at the request of various UK fresh food retailers and manufacturers, carried out an independent assessment of Catallix technology in comparison with chlorine. The challenge test was carried out (table 2), and the results are shown in table 3 and figures 2-4. These trials, carried out on iceberg lettuce, revealed that Catallix was more efficient than chlorine in destroying the pathogens commonly found on fresh foodstuffs. The results also show an interesting aspect of the Catallix activity: the listeria kill by Catallix compared with chlorine is initially not as good, but after three days the Catallix kill has increased. This is because by using the OSCN- the listeria is critically injured and recovery is made unlikely. On the Campden tests the second analysis was taken at day three; however, other tests have shown that the same kill rate seen at day three is obtained within a matter of hours (the initial analysis was within 30 minutes of washing with Catallix/chlorine). In addition to the antibacterial effects, other benefits when using the technology for the treatment of fresh foods include: • no neo-formed compounds (in the packaged product, there is no toxic compound such as organo-chlorinated compounds) • safety of the employee environment (no risk to the production staff) • final product has no changes to taste or mouthfeel • packaged product smells only of vegetables • the molecule has no negative effects on micro-organisms in environmental areas, (e.g. rivers, soil, sewerage systems), thereby allowing easy disposal of waste water. "The Catallix product is crystal clear, like sterile water. It has no smell or taste and is totally recyclable. We have seen that it can actually improve not only the flavour of washed salad and vegetables, because there is no chlorine deterioration in the finished product, but also the shelf life of the treated products," commented Richard Stead, from UK supplier Rigest.