Bioplásticos produzidos a partir de subprodutos de processamento de laranja
Carregando...
Data
2022-05-31
Autores
Santos, Leticia Bueno dos [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
A crescente conscientização em relação à saúde e alimentação, bem como mudanças de hábitos alimentares, aliadas ao aumento populacional, têm aumentado a demanda por frutas e seus subprodutos. Ainda que muitas frutas sejam principalmente consumidas in natura, muitas frutas são processadas em produtos mais estáveis, convenientes, baratos de transportar e com maior valor agregado. O processamento de frutas gera uma grande quantidade de resíduos e subprodutos, que são comumente descartados ou subutilizados. As comunidades científica e industrial têm, nos últimos anos, destinado a esses resíduos crescente interesse e atenção, buscando identificar e criar estratégias para seu reaproveitamento, convertendo-os em novos materiais e produtos. Um exemplo são os bioplásticos, materiais biodegradáveis e/ou derivados de fontes renováveis. Vários estudos têm explorado os subprodutos de processamento agroindustrial como fontes de macromoléculas que podem ser usados para formular materiais, como filmes para embalagens de alimentos. Por outro lado, a utilização de subprodutos integrais apresenta alguns desafios a serem superados. As diferenças entre as variedades, assim como diferenças sazonais, regionais e de maturação, influenciam na composição da biomassa, tornando difícil prever as propriedades finais dos materiais obtidos. Outro desafio é a dificuldade em dissolver simultaneamente os componentes, principalmente os lignocelulósicos, em um solvente comum. O presente trabalho teve como objetivo produzir, em escala de laboratório, filmes a partir de resíduos integrais (brutos) de processamento de laranja, utilizando pré-tratamento hidrotérmico da biomassa lignocelulósica em autoclave. Os filmes foram formulados a partir do tratamento de diferentes frações de laranja (casca, bagaço e polpa), combinadas e individualmente, a fim de se avaliar suas propriedades. As formulações tiveram adição de agentes plastificante (glicerol) e antiespumante e foram avaliadas em termos de suas propriedades mecânicas, ópticas (cor e opacidade), de barreira ao vapor de água e morfológicas (MEV). As matrizes vegetais também foram caracterizadas por meio de FTIR-ATR e RMN de 13C. Os filmes apresentaram valores de resistência à tração de pelo menos 4 MPa e elongação na ruptura de pelo menos 7%. Dentre as formulações obtidas, o filme produzido a partir da fração de polpa foi o que apresentou menores valores de permeabilidade ao vapor de água. Os filmes também apresentaram atividade antioxidante e absorção de radiação UV, tornando-os candidatos para a utilização como embalagens ativas, por exemplo. Além disso, pode-se afirmar que o prétratamento hidrotérmico foi eficaz na produção de filmes coesos e homogêneos a partir de resíduos de laranja.
The growing awareness regarding health and nutrition, as well as changes in eating habits and an increasing world population have increased not only fruit consumption, but also the demand for fruits and their by-products. Although fresh fruits are the most usual form of consumption for many fruits, some of them are usually processed into more stable and convenient products, easy and cheap to transport, and also with added value. The fruit processing generates a large amount of residues that usually end up underutilized or disposed, causing several environmental problems. In the last few years, scientific and industrial communities have shown great attention and interest in these materials in order to identify and develop strategies to reuse these by-products. An example of material that can be obtained from fruit processing by-products are bioplastics. These are biodegradable materials from renewable sources, which can potentially be used as an alternative to conventional (petroleum-derived) plastics. Many studies have been exploring fruit processing by-products as sources of macromolecules that can be used as food packaging materials. Using the bulk waste, on the other hand, presents some key challenges, which need to be overcome. The large varietal, regional as well as seasonal changes in their composition have a significant influence in the biomass composition, making it difficult to precisely predict the final properties of the obtained material. Another challenge is dissolving some bulk materials (especially lignocellulosic ones) in a common solvent. The objective of this project was to produce, in laboratory scale, bioplastics from bulk orange waste, by using a hydrothermal pretreatment on the biomass (in an autoclave). The residue fractions (peel, pomace and finisher pulp) were tested individually and combined in order to have their properties evaluated. A plasticizer agent (glycerol) and an antifoaming agent were added, and the films had their opacity, color, tensile properties, water vapor permeability and surface ultrastructure evaluated. The components of the biomass itself were also evaluated through 13C , FTIR-ATR and Soxhlet extraction. The films presented tensile strength and elongation at break values of at least 4 MPa and 7% respectively. Among the formulations, the film made from orange pulp residue showed the lowest water vapor permeability. The films also showed antioxidant capacity and UV absorption, being potential candidates for applications like active food packaging. It can be stated that the hydrothermal pretreatment was effective for the production of cohesive and homogeneous films from orange residues. In general, these materials showed reasonable tensile properties, with results comparable to some other biopolymer materials in the literature.
The growing awareness regarding health and nutrition, as well as changes in eating habits and an increasing world population have increased not only fruit consumption, but also the demand for fruits and their by-products. Although fresh fruits are the most usual form of consumption for many fruits, some of them are usually processed into more stable and convenient products, easy and cheap to transport, and also with added value. The fruit processing generates a large amount of residues that usually end up underutilized or disposed, causing several environmental problems. In the last few years, scientific and industrial communities have shown great attention and interest in these materials in order to identify and develop strategies to reuse these by-products. An example of material that can be obtained from fruit processing by-products are bioplastics. These are biodegradable materials from renewable sources, which can potentially be used as an alternative to conventional (petroleum-derived) plastics. Many studies have been exploring fruit processing by-products as sources of macromolecules that can be used as food packaging materials. Using the bulk waste, on the other hand, presents some key challenges, which need to be overcome. The large varietal, regional as well as seasonal changes in their composition have a significant influence in the biomass composition, making it difficult to precisely predict the final properties of the obtained material. Another challenge is dissolving some bulk materials (especially lignocellulosic ones) in a common solvent. The objective of this project was to produce, in laboratory scale, bioplastics from bulk orange waste, by using a hydrothermal pretreatment on the biomass (in an autoclave). The residue fractions (peel, pomace and finisher pulp) were tested individually and combined in order to have their properties evaluated. A plasticizer agent (glycerol) and an antifoaming agent were added, and the films had their opacity, color, tensile properties, water vapor permeability and surface ultrastructure evaluated. The components of the biomass itself were also evaluated through 13C , FTIR-ATR and Soxhlet extraction. The films presented tensile strength and elongation at break values of at least 4 MPa and 7% respectively. Among the formulations, the film made from orange pulp residue showed the lowest water vapor permeability. The films also showed antioxidant capacity and UV absorption, being potential candidates for applications like active food packaging. It can be stated that the hydrothermal pretreatment was effective for the production of cohesive and homogeneous films from orange residues. In general, these materials showed reasonable tensile properties, with results comparable to some other biopolymer materials in the literature.
Descrição
Palavras-chave
biorrefinaria, resíduo cítrico, bioplásticos, biomassa lignocelulósica, biorefinery, citrus waste, bioplastics, lignocellulosic biomass