Banca de DEFESA: AUGUSTO BENE TOMÉ CONSTANTIINO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : AUGUSTO BENE TOMÉ CONSTANTIINO
DATE: 28/07/2022
TIME: 14:00
LOCAL: Remota
TITLE:

Microencapsulation of bioactive compounds by complex coacervation using amaranth biopolymers and hydrocolloids

KEY WORDS:

complex coacervation; microencapsulation; food fortification; edible film

PAGES: 154
BIG AREA: Ciências Agrárias
AREA: Ciência e Tecnologia de Alimentos
SUBÁREA: Engenharia de Alimentos
SPECIALTY: Instalações Industriais de Produção de Alimentos
SUMMARY:

Currently, there is an increase in the search for natural sources of polymers for the development of different food products due to their health benefits. Among several vegetables, amaranth (Amaranthus sp.) can be highlighted for containing relatively high concentrations of starch (up to 69%) and proteins (up to 18%). The health benefits of amaranth are broad, including lowering serum cholesterol, and antioxidant and hypoglycemic properties. Amaranth starches and proteins are biopolymers that can have many technological applications, from the production of films and emulsions to the microencapsulation of active ingredients. The objective of this thesis was to microencapsulate bioactive compounds by complex coacervation using amaranth biopolymers and hydrocolloids. Initially, the amaranth protein isolate (API) was modified with high-intensity ultrasound (HIUS). The effects of HIUS on API were pronounced in the increase of sulfhydryl groups, hydrophobic groups, and reduction of particle sizes. These modifications determined improvements in the water solubility and emulsifying properties of the API. At pH 6.5, about 90% of the vitamin D₃ (VD₃) was microencapsulated in heteroprotein complexes of ultrasound-treated API (API-U) and lactoferrin (LF). The microcapsules protected VD₃ from degradation during storage and photolytic degradation. They also protected VD₃ during the in vitro simulation of gastrointestinal digestion, allowing high bioaccessibility (B* = 47%). In addition, the microcapsules also protected 86% of VD₃ during bread production, thus ensuring their effectiveness in fortifying this food. Complex coacervates formed by API-U and sodium carboxymethylcellulose (CMC) were used to encapsulate betanin at pH 3. Because betanin is water-soluble, a water-in-oil-in-water double emulsion was formed. Betanin microcapsules with high encapsulation efficiency (EE = 87%), good thermal stability (50ºC), and a high B* (85%) were obtained. Betanin microcapsules were used to produce edible gelatine films and increased elongation at break values, reduced light transmission, and improved antioxidant properties. The release of antioxidants present in the films was governed by Peppas-Sahlim kinetic. In the end, beta-carotene (β-C) microcapsules were produced using complex coacervates of carboxymethylated amaranth starch (CMS) and LF as wall material. CMS with a degree of substitution of 0.27 showed high affinity when interacting electrostatically with LF. High EE of β-C (98%) was obtained at pH 5. The β-C microcapsules showed good thermal and photolytic stability. The release of β-C from microcapsules was low (19%) and slow in the aqueous food matrix (50% ethanol) compared to the oily matrix. Applying β-C microcapsules to manufacture gummy candies was feasible, allowing a B* of 22% and reducing its hardness and chewing. Therefore, the results obtained from the present work open a new perspective on the use of amaranth biopolymers in the microencapsulation of bioactive compounds by complex coacervation and show the possibility of applying these microcapsules in the food fortification and the production of Biologically active edible packaging.

BANKING MEMBERS:
Presidente - ***.548.996-** - EDWIN ELARD GARCIA ROJAS - UFF
Interna - ***.646.967-** - LOURDES MARIA CORRÊA CABRAL - EMBRAPA
Externo à Instituição - EDUARDO BASILIO DE OLIVEIRA - UFV
Externa à Instituição - RENATA CRISTINA FERREIRA BONOMO - UESB
Externa à Instituição - LOUISE EMY KUROZAWA - UNICAMP