| abstract |
The present invention relates to a composition for gauging the freshness of nitrogen-containing organic materials using ammonia, and to a device therefor. More specifically, the composition comprises an ammonia-dependent nicotinamide adenine dinucleotide+ (NAD+) synthetase, an NAD derivative, an NAD+ reducing agent, and an NADH-selective indicator, and is capable of gauging the freshness of the nitrogen-containing organic materials by visually indicating the presence of ammonia after detecting the same. |