BIOSENSORS FOR FOOD INDUSTRY.

Novel biosensor systems were constructed for food industry. In order to determine fish freshness, a multifunctional enzyme sensor system was developed by combining a double membrane consisting of a 5 prime -nucleotidase membrane and a nucleoside phosphorylase-xanthine oxidase membrane with an oxygen electrode. Each nucleotide concentration was determined as the current decreased. One assay was completed within 20 min. Good comparative results were observed between the KI values determined by the sensor proposed and by the conventional method. An enzyme sensor for meat freshness consisted of a monoamine oxidase-collagen membrane and an oxygen electrode. The response time of the electrode was 4 min. A linear relationship was observed between the amine (tyramine) concentration in the range 50-200 mu M and the difference in current. Monoamine in meat extract was determined by the enzyme sensor. Micro-glutamate sensor was constructed using silicon fabrication technology.