Selection of Key Excipients and Optimization of Formula for Spray-dried Sweet Corn Nutritional Paste

【Objective】In order to analyze the effects of different types of food excipients on the dissolving ability and main carotenoid content of spray-dried sweet corn nutritional paste, and to screen the key excipients that are beneficial to improving the dissolving ability and carotenoid stability of spray-dried sweet corn nutritional paste, so as to provide a reference to producing high-quality spray-dried sweet corn nutritional paste.【Method】The water solubility index (WSI), dispersal time, caking rate, total content of lutein and zeaxanthin were used as evaluation indicators to select key additives for improving the dissolving ability and carotenoid stability of sweet corn paste by single-factor experiments. WSI, carotenoid (total lutein and zeaxanthin) content were used as evaluation indicators to optimize the slurry formula for preparing spray-dried sweet corn paste by response surface methodology. And practical applications verified the optimized formula.【Result】The additives such as maltodextrin, sucrose, and fructooligosaccharide which could significantly improve the dispersibility and carotenoids stability were defined as key excipients for spray-dried sweet corn paste. The optimal homogenate formula for preparation of sweet corn nutritional paste by spray drying obtained by response surface optimization was as follows: 25% maltodextrin, 1% fructooligosaccharide and 12% sucrose, calculated based on sweet corn dry base. Verification experiments of the the optimized slurry formula showed that the WSI of the spray-dried sweet corn flour was 70.67 (±1.24)%, and the total lutein and zeaxanthin content was 152.12 (±1.30) μg/g (dry weight). Compared with sweet corn flour without additives, the WSI increased by 34.84%, and the total lutein and zeaxanthin content increased by 11.37%.【Conclusion】Compared with protein and lipid, carbohydrate such as maltodextrin, sucrose, and fructooligosaccharide could significantly improve the dissolving ability and carotenoids stability of sweet corn paste and therefore could be used as key excipients for the preparation of sweet corn nutritional paste by spray drying. This study provided a feasible formulating way for producing high-quality sweet corn nutritional paste by spray drying, which could effectively improve the dissolving ability and the stability of carotenoids.