RICE GROATS FRESHNESS DETERMINATION METHOD

摘要

FIELD: food industry.SUBSTANCE: groats sample is collected and boiled in water at a ratio of 1:3 during 15-20 min for intensification of aroma and then cooled to 20-25°C. Then one collects five samples, 5 g each, into five vials and places them into the automatic sampling device. Analysis is performed using a VOCmeter type multisensor system for identification of components of gas mixtures. The samples are heated to 50-55°C during 10-20 min with volatile substances passed through the four non-selective metal oxide sensors. The electrical conductivity of the sensors sensitive layer changes in the presence of the ample volatile components, converted to an electrical signal. Then the signal is computer-processed and compared to reference samples data by the principal components method. The report is retrieved in the form of a diagram by which one determines the coordinates of the gravity centre of the cluster of five points corresponding to the cluster centre along the principal components axis. Rice groats are regarded fresh if the cluster gravity centre is not in excess of 25000 conventional units.EFFECT: invention ensures quantitative determination of rice groats freshness and reduces analysis duration and labour intensity.2 ex, 4 dwg