METHOD OF IDENTIFICATION OF GRANULATED HOPE SAMPLES BY ODOR WITH CHEMICAL SENSORS Russian patent published in 2018 - IPC G01N33/00 

FIELD: chemistry.

SUBSTANCE: invention relates to analytical chemistry and can be used to assess the identity or authenticity of food products, namely, granulated hop samples from different batches. To do this, sample preparation is carried out and an equilibrium gas phase is taken. Volatile odor components are identified using a "piezoelectronic nose" static detection device with a matrix of 7 chemical sensors based on piezoelectric quartz resonators, the electrodes being pre-modified with sorbent films. To this end, solutions of polyvinylpyrrolidone, polyethylene glycol phthalate, polyethylene glycol succinate, polyethylene glycol PEG-000, dicyclohexane-18-crown-6, bee glue (propolis), polyethylene glycol sebacate are applied to the electrodes so that the weight of the films after drying is 10–15 mcg. Responses of chemical sensors in the vapor of the equilibrium gas phase are fixed for 60 s and formed as a sum signal into the "visual imprint" of the maxima, which is compared in the software of the instrument with the "visual imprint" of the maxima for the standard. Conclusion about the identity of the composition of the analyzed sample and the corresponding standard is made with a relative difference in the parameters of the figures by less than 20 %. With a relative difference of more than 20 % of the parameters of the "visual fingerprint" figures for the sample and standard, the differences in the composition of the mixture of highly volatile compounds are significant and the sample is not identical to the chosen standard.

EFFECT: invention provides express analysis to obtain qualitative and quantitative criteria that allow one to evaluate the degree of identity of granulated hop samples and to assess changes in the product during storage.

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