Akademik Veri Yönetim Sistemi
NCC-8 National Catalysis Congress, Ankara, Türkiye, 9 - 12 Eylül 2021, ss.120
Damaged starch ratio determines the amylolytic activity in the flour which dominates the
physical quality standard of the final product like color, strength etc.[1,2,3]. In the food industry,
amperometric method which is based on the amount of iodine absorbed by starch granules is used for
determination of damaged starch ratio. Besides longer analysis time, amperometric technique also brings
a cost of about 1-2% of the profit in the food industry [4]. Therefore these issues give birth to this study
for the purpose damaged starch analysis by using less amount of chemicals, at shorter analysis times. In
this study, as a preliminary step for a screen printed electrode system, platinum, glassy carbon (GC)
electrodes and synthesized catalaysts were tested in a three-electrode system with electrolytes mixed
with flours at different damaged starch ratios (at 16.5, 25 and 30 UCD values). For the electrochemical
tests related with iodine absorption, electrolyte solutions were prepared according to Medcalf and Gilles
principle [4]; cyclic voltammetry experiments were performed at five different sweep rates, 50-150
mV/s in the range of 0-1 V vs. SCE; and chronoamperometry experiments were carried out at a potential
of 1 V vs. SCE.
Electrochemical tests indicate that platinum electrode was more sensitive than GC electrode. In
addition, when graphenes synthesized by three different electrochemical exfoliation techniques [5,6]
used as an electrode material, it was seen that electrode materials synthesized in an electrolyte mixture
of dimethyl carbonate (DMC) and ethylene carbonate (EC) , LiClO4 and tetraethylammonium
tetrafluoroborate exhibit highest sensitivity to iodine absorbtion and ; for the three different electrode
materials, initial FTIR results indicate a peak related with C=C bond at a wavelength of about 1600 cm1
. Further electrochemical and spectroscopic results will also be presented to compare the
electrochemical sensitivity and chemical structure of synthesized electrode materials.
In addition to experimental work, iodine oxidation mechanism were also studied by simulation
of cyclic voltammetric experiments at different scan rates . It was seen that on GC electrode, iodine
oxidation follows EC mechanism. Further simulation works will be performed for the determination of
electrochemical mechanisms on other electrode materials.