Production of Glucose Syrup through Enzymatic Hydrolysis of Flint and Floury Corn Flour Mixtures and Evaluating its Properties as Cost-Effective Syrup

Corn starch derivatives, including glucose syrups, are nowadays widely used in food industry. Glucose syrup is used in food industry, not only due to its sweetening power and nutritional value, but also for its functional properties (moisture stabilization, softening ability, improving texture and preventing sucrose crystallization). Floury (soft) corn is usually used to produce glucose syrup, but the most imported corn in Iran is flint or hard corn which is all the year round available and consequently, using both corn flour types would be inevitable. Therefore, the purpose of this study was to investigate the effect of using flint (hard) and floury (soft) corn flour to produce glucose syrup. Four treatments including hard flour + soft flour in four ratios of 30% + 70%, 50% + 50%, 70% + 30% and 100% soft flour as control were prepared and the physicochemical and organoleptic properties of the produced syrups were evaluated. According to the obtained results, using flint corn flour affected physicochemical and organoleptic properties of the samples. Increasing the ratio of flint corn flour had significantly decreased DE (Dextrose Equivalent), soluble solids and pH of glucose syrups. Also induced the increasing of color parameters and sulfated ash values of the produced syrups. However, cost estimates indicated a reduction in the cost of raw materials and consequently general reduction in production costs by replacing hard corn flour. It can be concluded from the results that hard flour can be used on all surfaces, but the best treatment was 50% replacement level or a bit more, in the production which had a good effect on the properties of glucose syrup and showed more similarity with the control sample. All of these, along with being cost effective, appeared this treatment to have the potential of supposing as a sugar substitute in food industry.