Naslov
Influence of extraction time and particle size on conductometric determination of flour and semolina mineral content

Autori
Jukić, M. ; Ugarčić-Hardi, Ž. ; Koceva Komlenić, D. ; Kuleš, M. ; Pitlik, G.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
CERWORLD 21st, Book of abstracts / Collar, Concha - Madrid : AETC-Spanish Association for Cereal Science and Technology, Madrid, Spain, 2008

ISBN
978-84-612-4517-8

Skup
13th ICC Cereal and Bread Congress, Cereals worldwide in the 21st century: present and future

Mjesto i datum
Madrid, Španjolska, 15.06.2008. - 18.06.2008

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
mineral content; wheat flour; electrical conductivity; conductometric method

Sažetak
The ash (mineral) content serves as a measure for the flour extraction level 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 simple as possible. Common standard method (ICC Standard 104/1) for the ash determination prescribes an incineration of sample, using much time and energy. Conductometric determination of ash content (ICC Standard No. 157) based on the measuring of electrical conductivity in the flour extract takes less time and is cheaper than a common method. However, for the industrial purpose, conductometric method still takes too much time, because the procedure includes thermostating of flour-water suspension for one hour followed by centrifugation. Therefore, the aim of this work was to modify conductometric method insomuch that procedure could be simplified and shortened for implementation in the industrial environment. The effect of a shorter extraction time and the influence of electrical conductivity measurements were analyzed directly in flour-water suspension at room temperature (without previous centrifugation), using the simple portable (pocket) conductometer. Samples of wheat flour with the ash content ranging from 0, 403-1, 498% were tested. The ash contents were predicted by measuring electric conductivity in the flour-water suspensions every 10 minutes and results were compared with the results obtained with the standard method of incineration. In addition to that, influence of flour particle size was also studied with samples of semolina of different particle size but with the same ash content. The obtained results showed that electric conductivity measurements can provide high precision results of flour ash content even if analysis are carried out directly in flour-water suspension at room temperature for only 30 minutes (without previous centrifugation) considering the fact that flour particle size should also be taken into account. Therefore, this modification of conductometric method (ICC Standard No. 157) could have an excellent application in industrial practice in cases when it is necessary to have rapid feedback of ash content values in wheat flour. References: ICC Standard No. 157. Standard Methods of the International Association for Cereal Chemistry. Verlag Moritz Schäfer, Detmold (1995). Ugarčić-Hardi Ž., Kuleš M., Koceva Komlenić D., Kuleš A., Jukić, M., Sabo M.: Comparison between conductometric and standard methods for ash determination in wheat flour, Proceedings of International Congress Flour-Bread '01, Faculty of Food Technology Osijek (2002) 29-33. Clements RL.: Electrical conductivity of flour suspensions and extracts in relation to flour ash, Cereal Chemisry (1977) 54, 847-854

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

POVEZANOST RADA