wind solar family power supply system Hengfeng Wind Power Generator Co., Ltd. , http://www.china-wind-turbines.com
Freshness is one of the important indicators for evaluating food quality. It is usually tested by human perception, but the sensory test is subjective and individual differences, so people have been looking for objective physical and chemical indicators instead. Volpe et al. used xanthine oxidase as a biosensing material, combined with a hydrogen peroxide electrode, to measure the inosine monophosphate (IMP), inosine (HXR) and hypoxanthine (HX) produced during fish degradation. Concentration to evaluate the freshness of the fish.
Here, the freshness sensing system is composed of a mixed membrane of xanthine oxidase and nucleoside phosphate oxidase and an oxidizing electrode, and the measurement can reach 20%. The K value of the target fish, squid, horse mackerel, wolf squid, etc. has been measured using this sensor. In addition, if the amount of IMP, HXR, and HX is radiated to the three axes (radar pattern), the freshness can be evaluated from a visual angle according to the stripe shape.
Now, European and American countries use the amount of histase to evaluate freshness. Histamine is a toxin that causes food poisoning. It can be produced when fish are left for a long time. In the future, the K value measurement and the histidine enzyme measurement can be used simultaneously in the measurement, and the safety of the food can be ensured more reliably.
Freshness can also be evaluated using an olfactory sensor (gas sensor). The odor of trimethylamine (TMA) in the ammonia series is the same as that of the fish when it is not fresh (smelly smell). Therefore, we can try to use TAM oxide semiconductor as the measurement sensor. For example, when measured using ruthenium titanium oxide, its electrical resistance will decrease as the degree of deterioration of the fish. Therefore, the degree of reduction in freshness can also be evaluated by the reduction in electrical resistance. Can be used for fresh-keeping packaging of aquatic products.
There is also a report on the evaluation of the taste and quality of the instrument using a multi-membrane potentiometer-type taste sensor. Make our future food packaging safer.
Latest developments in food freshness sensors
Biosensors can be widely used in the production of food industry, such as the detection of food raw materials, semi-finished products and product quality, online monitoring in fermentation production. Various amino acids (including more than ten amino acids such as glutamic acid, L-aspartic acid, and L-arginine) can be determined by using an amino acid oxidase sensor. There are many types of food additives, such as sweeteners, sour agents, antioxidants, etc., and biosensors have been reported for the analysis of food additives.