Stability of antioxidants encapsulated in freeze-dried prebiotic matrices

FAROUX, J.M.; URETA, MARIA MICAELA; GOMEZ ZAVAGLIA, A.; TYMCZYSZYN E. E.

Basic Protocols in Encapsulation of Food Infredients

Springer

Año: 2021;

Preservation of bioactive compounds present in food has been the subject of various studies in the last decade. Freeze-drying microencapsulation is a methodology used to preclude degradation of such sensitive compounds (1).The ability of some prebiotic compounds, such as galactoand fructo-oligosacharides (GOS and FOS, respectively), to form amorphous solids (glass matrix) underlines their importance as food components potentially enabling the encapsulation of functional ingredients.However, these amorphous solids can lose this glassy state under certain storageconditions(e.g., high temperature and humidity), which is known asglass transition.This phenomenon can impact negatively in the integrity of the bioactive components by collapse of the matrix structure(2).FOS and GOSarecomplex mixtures of oligosaccharides with different degrees of polymerization (DP),well known for their prebiotic properties.Additionally, as they have a sweet flavor and are not hydrolyzed or absorbed in the upper part of the gastro-intestinal tract, the arrive unaltered to the gut, thus contributing to the body weight control as low caloric sweeteners, and also giving the feeling of (3).Vitamin C, also known as ascorbic acid, is involved in several body functions (e.g., formation of collagen, iron absorption, immunomodulation, wound healing, maintenance of cartilage, bones, and teeth). However, it is very labile to heat, oxygen, technological and physiological processes. Therefore, retention of vitamin C is of great importance to ensure its biological functions. Furthermore, as its retention correlates well with that of other nutrients in food, it can be used as a model to study the stability of other bioactive components in processed, dried and store food (2).In order to evaluate the ability of different freeze-driedprebiotic matrices to stabilizelabile nutrients, solutions of GOS, FOS and sucrose(control sample) were used as protectant of freeze-dried ascorbic acid samples stored in different conditions.