Encapsulação do óleo essencial de laranja em β-ciclodextrina: Ação antifúngica e aplicação em bolos

Abstract

This work was divided into five studies. The first study was performed to establish the best conditions in the formation and stability of inclusion complex between cyclodextrins (Cds) and orange essential oil by the co-precipitation technique, using the commercial β-cyclodextrin (β-CD). Inclusion complexes were evaluated for their chemical composition, morphology, thermal stability and analysis of volatile compounds through the headspace technique. The slow loss of the essential oil volatile compounds, when complexed with β-CD, showed greater stability compared to its physical mixture and its free form. Therefore, the results showed that the use of β-CD in the inclusion complexes with orange essential oil formation can expand to potential applications in foods. In a second study, the objective was to produce CDs from germinated wheat starch for encapsulation of orange essential oil and evaluation of the thermal stability of the inclusion complex formed. The germination increased the enzymatic activity of all the samples, as well as a greater production of cyclodextrins. In addition, the inclusion complex formed between CDs/OEL significantly improved the thermal stability of the orange essential oil, promoting its protection at high temperatures. Despite the promising result, the difficulty to separate the cyclodextrins and the reducing sugars from the solution and the low yield obtained, prevented the use of these in the following steps. Therefore, it was decided to use the commercial cyclodextrin, which presented satisfactory results in the first study. The third study aimed evaluated the effect of the process used (electrospinning or electrospraying) on the efficiency of encapsulation of orange essential oil was evaluated, where the electrospinning process proved to be more efficient for the encapsulation of the orange essential oil with high encapsulation efficiency. . In the fourth study in vitro antifungal activity of orange essential oil (OEL) was evaluated against six isolates of Aspergillus spp. was evaluated, as well the in situ antifungal activity of OEL, in free form and encapsulated, in cakes. The results showed that OEL ncreased the microbiological stability of cakes, delaying the fungal contamination of the cakes from 30 to 150 days. In the latter study, the free OEL and encapsulated in β-cyclodextrin was applied to cake pre-mixtures, which were stored for 6 months. The cakes obtained from these pre-mixtures were evaluated at time zero and after 3 and 6 months of storage. The β-CD/OEL cake presented higher volume after storage of the respective premix for 6 months; lower hardness and lower percentage of hydrolyzed starch after in vitro digestibility. On the other hand, in the sensorial analysis, the cake with free OEL was preferred by 60% of the panelists.