Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 7, pp. 1195−1199.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
S.M. Butrim, V.V. Litvyak, V.V. Moskva, 2009, published in Zhurnal Prikladnoi Khimii, 2009, Vol. 82, No. 7, pp. 1098−1103.
OF SYSTEMS AND PROCESSES
A Study of Physicochemical Properties of Extruded Starches
of Varied Biological Origin
S. M. Butrim
, V. V. Litvyak
, and V. V. Moskva
Research Institute of Physicochemical Problems, Belarussian State University, Minsk, Belarus
Scientiﬁ c-Practical Center for Food of the National Academy of Sciences of Belarus,
Republican Unitary Enterprise, Minsk, Belarus
Received November 11, 2008
Abstract—Morphological structure of native and extruded starches of varied biological origin was studied, their
X-ray phase analysis was made, and their solubility in cold water was examined.
Modiﬁ ed starch products are extensively used in
food, pulp-and-paper, building, and other industries.
Most widely occur starch products modiﬁ ed by various
chemical and biochemical methods (esterification,
oxidation, cross-linking, acid and enzymatic hydrolysis)
At present, steadily increasing attention is being given
to “healthy” feeding, with the result that a tendency
is observed for chemically modified products to be
gradually abandoned, which is due to difﬁ culties in
their puriﬁ cation to remove toxic low-molecular-weight
chemical substances unreacted with a polysaccharide or
formed in the course of its modiﬁ cation. In some cases,
a thermomechanical modiﬁ cation of starch-containing
products can serve as a good alternative to chemical
modiﬁ cation. An extrusion treatment of starch in various
modes can yield products with prescribed quality
parameters, which can satisfy the demand of various
The key role in the formation of target properties of
thermomechanically modiﬁ ed starch products is played
by changes in their physicochemical properties in the
course of an extrusion treatment. It is important to note
that differences in morphology and physicochemical
characteristics (moisture content, amount of amylose,
etc.) between starches of varied origin affect the extent
to which their structure and physicochemical properties
change in the course of extrusion .
The aim of this study was to perform a morphological
and X-ray diffraction analysis of potato, corn, and tapioca
starch subjected to extrusion treatments under various
conditions. In addition, the effect of extrusion on the
moisture content and solubility in cold water of extruded
starch products was analyzed.
As objects of study served extra-quality potato starch
[GOST (State Standard) 7699–78, Belarus), extra-quality
corn starch (GOST 7697–82, Russia), and tapioca starch
The extruded starches were obtained at Mashpishcheprod
Open Joint-Stock Company (Mar’ina Gorka) on an RZ-
KED-88 double-screw extrusion installation under the
following conditions: temperature 140–170°C; rotation
frequencies of the dosing screw, working screws,
and cutting device, 90–92, 90–94, and 80–84 rpm,
respectively; matrix (extrusion nozzle) diameter 4 mm;
no preliminary moistening of the raw material.
The morphology of structural units constituting
particles of native starches and extruded starch samples
was studied with a LEO 1420 scanning electron
microscope (Germany). When fabricating preparations,
powdered starch samples were deposited onto a metallic
substrate and ﬁ xed on its surface with an electrically
conducting glue. Then a gold layer was deposited in an
EMITECH K 550X vacuum installation (Germany).
Diffraction curves were recorded on an HZG-4A X-