masterThesis
Desenvolvimento de filmes biodegradáveis ativos contendo coprodutos da extração de própolis comercial e da indústria de suco de maçã
Fecha
2019-10-29Registro en:
BERTOTTO, Carlize. Desenvolvimento de filmes biodegradáveis ativos contendo coprodutos da extração de própolis comercial e da indústria de suco de maçã. 2019. Dissertação (Mestrado em Tecnologia de Processos Químicos e Bioquímicos) - Universidade Tecnológica Federal do Paraná, Pato Branco, 2019.
Autor
Bertotto, Carlize
Resumen
Active packaging is an innovative approach to maintain or extend the lifespan of food products, ensuring their quality, safety and integrity. The addition of active substances, such as antimicrobials and antioxidants may extend shelf life and decrease the use of preservatives in foods. Based upon this theoretical basis, the main goal of this study was to develop active films with the co-product (CP) from propolis commercial extraction, as well as with apple juice co-product (CM) in order to create a biodegradable plastic packaging for food use. Initially, CP and CM were described regarding their physicochemical composition (moisture, ashes, protein, lipids, glucose and fiber sugars). Subsequently, the biodegradable plastic films containing the co-products produced by blow extrusion in balloon were analyzed regarding their physical properties (elasticity, flexibility and stiffness of the films). Ethanolic extracts of co-products and plastic films containing co-products were prepared and analyzed for total phenolic content, antioxidant activity and antimicrobial activity. In addition, the profile of volatile compounds of these materials were determined by solid phase extraction, these compounds were also identified and quantified by gas chromatography coupled to the mass spectrometer. The content of total phenolic compounds was determined by the Folin-Ciocalteau method, while the antioxidant activity was determined by four methods: DPPH (2,2-diphenyl-1-picrylhydrazine); ABTS 2,2-azino-bis- (3-ethyl-benzothiazoline-6-sulfonic acid) and FRAP (iron reducing antioxidant power). Antimicrobial activity was determined by the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (CBM) against the microorganisms Staphylococccus aureus, Salmonella thyphimurium and Escherichia coli. As a result, both co-products showed phenolic and antioxidant activity and could be used to make the active packaging. The CP presented MIC against the Staphylococccus Aureus bacterium at the concentrations of 12.5 e 6,25 mg/mL. Regarding the mechanical properties of flexibility, strength and stiffness the added concentrations of co-product were satisfactory compared to the control film. By the volatile analysis, it was possible to detect 118 compounds for CP and its respective film, and 65 compounds for CM and its respective films. The major classes of compounds identified were terpenes, esters and aldehydes, with benzenopropanoic ethyl ester acid with 25.13% for PC and 32.93% in the 4% CP film of the total area for esters. For the CM and its respective films, 65 compounds were identified, the classes with the largest number of identified compounds were aldehydes, esters and terpenes, highlighting the compound α-Farnesene representing 25.72% of the total area for the class of terpenes.