3. Hygienic quality control

Agricultural products - and, in particular, those of animal origin such as eggs and milk - contain proteins with bactericidal or bacteriostatic properties. These biomolecules are either lytic (lysozyme E.C.3.2.1.17), or inhibit micro-organisms (peroxidase E.C.1.11.1.7). These properties are used to control the hygienic quality of foodstuffs. In addition, certain enzymes such as catalase (E.C.1.11.1.6) or β-lactamase (E.C.3.5.2.6) can destroy molecules that have been introduced into the medium (hydrogen peroxide, antibiotic); other biocatalysts (e.g. glucose oxidase E.C.1.1.3.4) generate inhibitory products in the medium [6] .