Application of enzymes for food protection

i) Enzymes as antioxidants
Enzyme catalysis can be employed as antioxidant principle by a) removal of active oxygen species, b) competitive removal of oxygen, c) reduction of lipid hydroperoxides. The effect of all three principles was tested by us in previous projects. we have thus shown that enzymatic removal of oxygen is an efficient and that reduction of lipid hydroperoxides is a workable principle. The present objectives are to study the efficacy of new oxidases and to continue the studies on application of peroxidases to reduce lipid hydroperoxides.
ii) Inhibition of microbial growth by lytic enzymes
Lysozyme (EC 3.2.1.17) catalyses hydrolysis of peptidoglycan in bacterial cell walls. Lysozyme from hen egg white has been approved as a food additive in EU to inhibit late blowing of hard cheeses caused by Clostridium tyrobutyricum. We investigate the antibacterial effect of lysozyme. In particular the effects of various micro-enviromental food parameters on stability and activity of the enzymes.