Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/15/2004
Publication Date: 5/30/2004
Citation: Johnston, D., Thomas, J.L. The effects of processing chemicals on corn starch pasting properties. Proceedings of the Corn Utilization & Technology Conference, Indianapolis, IN., June 7-9, 2004. Poster Presentation CD Rom.
Technical Abstract: The use of starch pasting properties to monitor starch quality is a common practice in research and industry. Several companies sell dedicated equipment designed to measure these properties. In our laboratory we have used the RVA-4 as a tool to measure the pasting properties of starches generated using enzymatic wet milling (Johnston & Singh, 2001, Singh & Johnston 2002). With enzymatic wet milling studies, we have used a variety of pH modifiers, sulfur dioxide, enzymes and other chemicals that could potentially remain and alter the pasting properties of the starches we produce. In this work we addressed the effects that these compounds have on the pasting properties by adding them at several concentrations to a standard starch and measuring a standard pasting profile. We examined the effects of lactic acid, acetic acid, sulfur dioxide, sodium chloride, sodium acetate and sodium hydroxide. Each compound was added in at least two different concentrations and each was done in triplicate. Statistical analysis of each was compared to water as the standard control. Statistically significant differences were determined for peak, setback, breakdown, and final viscosities as well as for peak time and pasting temperature. While differences were not found for all the compounds tested, the effects shown indicate how difficult comparison between pasting properties for starches milled using different procedures can be. The potential use of a standard buffering system for measuring pasting properties is currently being examined.