Inulin/fructooligosaccharides/pectin-based structured systems: Promising encapsulating matrices of polyphenols recovered from jabuticaba peel

Abstract

Abstract This paper investigated the effects of fructooligosaccharides (FOS) and inulin with different degrees of polymerization (DP) on the rheological, physical, and microstructural properties of pectin-based structured systems and their performance as encapsulating matrices of polyphenols extracted from jabuticaba (Myrciaria jabuticaba (Vell.) Berg) peel. The pseudoplastic pectin-based systems presented a predominantly viscous behavior. The addition of FOS diminished their apparent viscosity and the consistency index. On the other hand, the increase of inulin DP increased them. The rheological characteristics and microstructure found in the pectin-based encapsulating systems with the addition of inulin with DP\xa0≥\xa023 (P\xa0+\xa0IN23) enable its use as a functional structuring food ingredient. The addition of inulin darkened the samples with the increase in DP, indicating better color retention in the pectin-based matrix with higher inulin DP. It also showed the highest values of chemical properties like bioactivity and encapsulation efficiency (EE) (85.7%), followed by the sample with the addition of inulin with DP\xa0≥\xa010 (P\xa0+\xa0IN10) (80.6%), and the sample with the addition of FOS (P\xa0+\xa0FOS) (77.9%). Pectin-based sample (P) had the lowest values and EE (75.5%). Therefore, the addition of inulin improved these parameters, and this improvement was gradual with the increase of DP. During the four weeks of stability evaluation, only P\xa0+\xa0IN10 and P\xa0+\xa0IN23 samples remained stable. In the last week evaluated, P\xa0+\xa0IN23 presented the highest percentage of relative oxygen radical absorbance capacity (94%), and the values decreased with the decrease of DP (P\xa0+\xa0IN10\xa0=\xa076% and P\xa0+\xa0FOS\xa0=\xa061%). The P encapsulating matrix presented the second-highest percentage (82%). P and P\xa0+\xa0IN23 samples were efficient in protecting the jabuticaba peel extract. They exhibited good retention of the antioxidant capacity. Likewise, the inulin addition and its molecular chain size contributed to the binding reordering of the system.