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Several analytical methods have been developed to characterize starch properties and concentration in products and by-products before and after processing. In sugar manufacture, starch is considered an impurity and is, therefore, quantified so that processing aids can be added or processors can be modified if necessary. Current sugar industry starch methods use extensive heating to completely solubilize starch and iodine to measure soluble polysaccharides since enzymes are too expensive and labor intensive. These methods are simple, rapid, and selective, use a soluble potato starch standard (which is not an ideal model for sugarcane starch), but are unable to effectively solubilize or accurately quantify starch amounts in various factory products like juices, massecuites, molasses, syrups, or raw and refined sugars. The newly developed USDA Starch Research method, based on microwave-assisted probe ultrasonication, offers the ability to solubilize <40 g/L insoluble starch in 6 mins while extrapolating results to a corn starch (which corn and sugarcane are both grasses and very similar) standard curve and incorporating a color correction step. This is the only method that quantifies total, insoluble, and soluble starch in various products. The method was validated following the International Commission for Uniform Methods of Sugar Analysis and found to be applicable to sugarcane and sweet sorghum bagasse (3% CV), mixed juices (2%), massecuites (4%), molasses (7%), and raw sugars (12%) and, 100% satisfactory performance z-scores were also obtained. Total starch values obtained with the USDA Starch Research method were significantly higher than those measured using other sugar industry methods. Future work includes expanding the utility of this method to other starch industries.