Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 7, pp. 1188−1194.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
T.A. Kuchmenko, Yu.A. Asanova, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 7, pp. 1092−1097.
OF SYSTEMS AND PROCESSES
Use of Piezosensors for Determining the Composition
of the Equilibrium Gas Phase of Aqueous Protein Solutions
T. A. Kuchmenko and Yu. A. Asanova
Voronezh State Technological Academy, Voronezh, Russia
Received May 27, 2008
Abstract—Possibility of using modified piezosensors to determine the composition of multicomponent gas
mixtures was studied. The sorption conditions of readily volatile components of aqueous protein solutions on
modifier films of varied nature for piezoquartz resonators were examined and optimized. A set of methods for
determining aroma-forming components of complex mixtures was developed. The possibility of using the methods
developed for determining the nature of aroma-forming additives to milk drinks was demonstrated.
The increasing impact of anthropogenic contaminants
on the tropo-, hydro-, and atmosphere leads to severe
negative changes in not only physical and moral, but
also social health of humans and human society. The
contamination of air, water, and soil and the possibility
of their being severely damaged has become a frequent
topic only recently; because of pronounced changes
in technologies and formulations in food industry, the
problem of safe food products is being openly discussed.
Undoubtedly, toxic and poorly studied food components
are the most hazardous to the human health.
According to the International Health Organization,
80–90% of substances foreign to humans comes with
foodstuff, 4–7%, with water, and an even lesser amount,
with air . About 5% of samples of domestic products
fail to satisfy hygienic regulations in their sanitary-
chemical parameters .
Contamination of food raw materials is possible
via introduction of artiﬁ cial additives (aromatizers,
dyes, stabilizers, emulsifiers), by metabolites of
microorganisms used in manufacture of food, and
by anthropogenic substances via soil, water, and
raw materials. It is known that the same substances
are differently distributed among the main matrix of
food or nonfood nature and the gas phase and thereby
determine numerous quality and safety parameters of
ﬁ nished products (emission level of readily volatile
components from plastics, aroma of food products).
As a consequence, there is an increased interest in
development of new methods for detecting trace
amounts of readily volatile components in complex
mixtures, including protein matrices.
The aim of the study was to develop a set of methods
for determining microscopic concentrations of alcohols,
aldehydes, ketones, carboxylic acids in a gas phase that
is in equilibrium with aqueous protein solutions by the
As detecting elements served piezosensors in the form
of AT-cut piezoquartz resonators (PQRs) with sensitive
sorbent ﬁ lms on their electrodes.
In development of methods for determining how
the composition of gas media changes, the following
problems were to be solved: choice of the optimal
modiﬁ er ﬁ lms for PQR electrodes, sensitive to the
main readily volatile components of aqueous protein
solutions and inert toward water vapor; modeling and
fabrication of an array of piezosensors; development
of an algorithm for formation of the overall response
of the detector, processing of the experimental results
(matrix of piezosensor responses), and deciding on the
composition of the equilibrium gas phase (EGP); and
development of a set of methods for determining trace
amounts of aroma-forming components in complex
mixtures (for the example of milk drinks).