Production of resistant maltodextrin and starch as novel prebiotics by the reaction of maltodextrin and starch with malic acid and citric acid

Resistant maltodextrin and starch are indigestible food components that reach the colon intact, serving as nutrients for Bifidobacteria and Lactobacilli. As typical dietary fibre, they are among the most beneficial due to higher solubility in water. In our experiments, we produced resistant maltodextrin and resistant starch via reactions between maltodextrin or starch with malic acid and citric acid under controlled concentrations, durations, and optimal temperatures. We determined the optimal reaction parameters, estimated the consumption of starting materials and the formation of end-products by measuring the two organic acids, examined the molecular weight distribution, glucose equivalent, and purity of the maltodextrin, and tested the resistance of the products after enzymatic hydrolysis. In vitro experiments confirmed that the final products (resistant maltodextrin and starch) exhibit high resistance to carbohydrate-degrading enzymes, a fundamental requirement for any resistant food component to effectively serve as a nutrient for probiotic bacteria in the colon.