The accumulation of saffron corms as agricultural waste and the inherent limitations of native starch such as poor cold-water solubility and structural instability necessitate the development of clean-label modification techniques. This study aimed to optimize the thermosonication of saffron corm starch (UHSCS) and comprehensively compare its physicochemical, structural, and functional properties with native (NSCS) and commercial pre-gelatinized starch (CPGS). A matrix of ultrasound amplitudes (50%, 75%, 100%), temperatures (25°C, 50°C, 100°C), and durations (10, 20, 30 min) was screened to evaluate the interactive effects of these variables. The optimal condition, yielding maximum solubility (16.02%), was identified at 75% amplitude, 50°C, and 30 min. Under these conditions, UHSCS exhibited a swelling power of 43.94 at 90°C (compared to 14.84 for NSCS) and a shift toward smaller granules, with a reduced volume-weighted mean diameter (D4,3). XRD analysis indicated increased crystallinity while maintaining the B-type structure. DSC analysis showed elevated onset (67.62°C) and peak (73.73°C) gelatinization temperatures with reduced enthalpy (11.69 J/g). Syneresis and turbidity were significantly reduced during storage compared to NSCS. Color parameters revealed that UHSCS had significantly higher redness ( a * = 3.185) and yellowness ( b * = 19.99), along with a 95.7% higher whiteness index than CPGS. These structural and functional enhancements demonstrate that thermosonication effectively overcomes native starch limitations, making UHSCS a highly promising clean-label thickener, stabilizer, and texture modifier for applications in soups, sauces, and dairy alternatives.
Einafshar et al. (Fri,) studied this question.