engleski

Modified conductometric method of ash determination in wheat flour

The ash (or mineral) content serves as a measure for the share level of layer particles in flour and is used for determining the flour type. It is necessary, especially during wheat milling, to determine the ash content in wheat flour as fast and as simple as possible. There are two methods for determining the ash content according to ICC Standard Methods: method of incineration (ICC– Standard No. 104/1) and the method of ash determination by conductivity (ICC-Standard No. 157). Since these two methods take a lot of time, we tried to modify conductometric method insomuch that procedure could be simplified and shortened. ICC-Standard No. 157 demands thermo stating of flour suspension during 1 hour at 30°C and 5 minute centrifugation at 4000 rpm. We, therefore, tested the influence of a shorter extraction time and the influence of electrical conductivity measurement directly in flour-water suspension (without previous centrifugation) on result accuracy. Fifteen samples of wheat flour with the ash content ranging from 0.403 to 1.536 % were tested. Based on the gained results, it could be concluded that electric conductivity measurements indicate high precision results even if carried out directly in flour-water suspension and after only 15 min. Thus, the standard conductivity method of determining the ash content in wheat flour is being modified and therefore, this particular way of determining ash content, is far more simpler, faster and less expensive than the standard method of incineration (ICC– Standard No. 104/1) and the method of ash determination by conductivity (ICC-Standard No. 157). So, it could have an excellent application in industrial practise in cases when it is necessary to quickly obtain data.

wheat flour; ash; conductometric method

nije evidentirano