Banca de DEFESA: NAYARA TAÍNE BOHNENBERGER

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : NAYARA TAÍNE BOHNENBERGER
DATE: 18/03/2024
TIME: 08:30
LOCAL: Campus Feliz (defesa online)
TITLE:

COMPARATIVE STUDY OF METHODOLOGIES FOR ADDING THYME ESSENTIAL OIL TO CASSAVA STARCH-BASED FOAM: EFFECTS ON THE PROPERTIES OF THE MATERIAL

KEY WORDS:

Starch foam. Essential oil. Active packaging.

PAGES: 88
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Polímeros, Aplicações
SUMMARY:

Nowadays, the packaging industry has been striving to meet the increasing market demands for sustainable and active materials. In this scenario, the use of starch becomes promising, especially when combined with essential oils, which have antimicrobials and antifungals properties. However, the volatility of these substances represents a challenge. Therefore, this study aimed to evaluate two methods of incorporation of thyme essential oil into cassava starch foams, focusing on the characterization of their physical, chemical, morphological, mechanical, thermal, and microbiological properties. Initially, the minimum inhibitory and minimum bactericidal concentrations of the essential oil were determined. Then, this substance was incorporated into sodium montmorillonite clay, using the emulsion method. After that, the starch foams were produced by mixing with a magnetic stir, followed by the thermoforming. The addition of the essential oil occurred through the incorporation of the clay hybrid in the formulation and the application of this substance on the surface of the foams.  Minimum inhibitory and bactericidal concentrations of 12,5 e 25 %(v/v), respectively, were verified. The highest amount of incorporated essential oil (~18,88%) was reported for the clay sample produced with Tween 80. The loss of part of the essential oil was verified through the thermogravimetric analysis, when simulate the starch foam processing conditions. However, the presence of this substance was detected in the E-HB through FTIR, after thermoforming. When comparing OET incorporation techniques, E-HB showed greater thermal stability. However, the E-SUP-25 sample presented smaller and more closed air bubbles, greater impact resistance, and lower water absorption rates compared to the E-HB. In the microbiological analysis, this sample presented inhibition zones of 2,82 ± 0,22; 2,85 ± 0,15, and 2,39 ± 0,22 cm against S. aureus, S. enterica and E. coli. Comparing E-NaMt and E-HB samples, the presence of essential oil in the interlayer space seemed to affect the interaction between starch and the clay. Therefore, among the methods analyzed, surface application was the most effective, being a promising alternative for application in food packaging, especially for products containing low water content.

COMMITTEE MEMBERS:
Externa à Instituição - Cleide Borsoi - UNIVATES
Interna - 2383615 - DAIANE ROMANZINI
Externa ao Programa - 1809526 - JANETE WERLE DE CAMARGO LIBERATORI
Externo à Instituição - MATHEUS VINICIUS GREGORY ZIMMERMANN - UNESC