Application of artificial smell systems for bakery products state monitoring

Abstract

Examples of the integrated analytical system "electronic nose" use to discover early signs of bakery products deterioration are studied in the article. The development of physical and chemical analysis methods goes along the path of samples composition differentiating and making decisions on the components set content that determine the product safety and quality. However, the differentiation and descriptor assessment of the integral organoleptic properties, especially of smell and taste, does not reflect the product true state. The development of innovative methods is based on the approximation of instrumental analysis of smell and taste to human perception. The results of quality assessment and changes in the state of white and black bread during storage by the signals of an array of chemical sensors based on highly sensitive piezoelectric scales are presented. Piezoelectric quartz microscales are modified with nanostructured phases of various nature and mass. Modifiers were selected taking into account their selectivity and sensitivity to easily volatile biomolecules, the content of which can be changed with the maturation or spoilage of bread, or during storage. As such phases, biohydroxyapatite, multilayer carbon nanotubes oxidized with nitric acid, zirconium nitrate are used. It was shown that the MAG-8 electronic nose signals based on eight piezosensors with nanostructured phases it is possible to detect changes in the state of bread by the qualitative and quantitative composition of the mixture of volatile biomolecules that the array is tuned to. For samples of a loaf of wheat flour and black bread, the composition of marker substances was determined, reflecting the nature of the products and their change during storage and spoilage. Changes in the content of water, acetic acid, ketones, alcohols, acetates and amines were noted in the article. The calculated parameters of the "electronic nose" associated with the content of these compounds and allowing them to be recognized in a mixture in the presence of other compounds were offered in the work.