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1.
Artigo em Inglês | MEDLINE | ID: mdl-38865045

RESUMO

Recognized for its bioactive compounds, açaí has become a functional food, but it has a low pulp yield, and the seeds are the main waste. This study investigates the potential of açaí seeds (Euterpe oleracea Mart.) to produce mannooligosaccharides (MOS) through enzymatic hydrolysis. Using response surface methodology (RSM), the research optimizes MOS extraction while minimizing mannose production and reducing processing time, achieving MOS production of about 10 g/L, a value within the range of similar investigations. The RSM quadratic models establish correlations between MOS production (M2-M5) and enzymatic hydrolysis conditions, with R2 values ranging from 0.6136 to 0.9031. These models are used to emphasize MOS performance (M2-M5) while reducing mannose production, which also promotes profitability by reducing time. Experimental validation agrees with model predictions, highlighting optimal conditions near 40 °C, intermediate enzyme loading, and basic pH that effectively promotes MOS generation on mannose within an accelerated processing time frame. With predictions of experimental results within a margin of error of < 9%, the validity of the models was acceptable. This research contributes to the advancement of the understanding of the enzymatic hydrolysis of açaí seeds, which is a step toward the sustainable use of resources with a focus on process engineering aspects.

2.
Data Brief ; 30: 105605, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32382614

RESUMO

This data article is related to the research article "Comparative life cycle assessment of coffee jar lids made from biocomposites containing poly (lactic acid) and banana fiber". The article reports the model parameters used to construct each stage and unit process inventory of the life cycle of coffee jar lids, and the subsequent inventories of the investigated system. It also contains details of calculations and descriptions of inventory uncertainties. Primary data were obtained from lab-scale and pilot-scale tests during product preparation. Secondary data collection was based on detailed review of related international and regional literature, databases and recognized web sites. The data presented here can be used by future life cycle assessment studies on natural fiber composites in packaging applications.

3.
J Environ Manage ; 266: 110493, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32310114

RESUMO

Composites containing bio-based materials, like banana fiber and poly(lactic acid) (PLA), are potential food-packaging materials. We carried out an environmental life cycle assessment (LCA) of coffee jar lids made from high density polyethylene (HDPE), PLA, and banana fiber to assess their environmental performance. We considered differences in the type of blend (content of PLA and banana fiber in the composite), origin of the banana fiber feedstock (considered as either biowaste or as a co-product from banana production) and banana fiber pretreatment conditions (either no pretreatment or pretreatment using chemicals). Irrespective of the scenario, a lid made from 40% banana fiber and equal amounts of HDPE and PLA performed significantly better in all 18 impact categories when compared to a lid made from 100% PLA. By contrast, the same lid performed significantly better in 3 impact categories only (climate change, photochemical oxidant formation and fossil depletion) when compared to a lid made from 100% HDPE. Thus, environmental performance of the biocomposite strongly depends on which polymer base is replaced by the banana fiber in the composite. Replacing PLA with banana fiber is generally expected to bring environmental benefits.


Assuntos
Musa , Café , Poliésteres , Polímeros
4.
J Food Sci ; 84(8): 2269-2277, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31339566

RESUMO

The objective of this study was to explore the drivers of choice and perceptions of healthiness that specific ingredient or energy content information displayed on the front-of-pack label of cereal bars triggers among different groups of consumers. The participants (18 to 50 years old), classified as exercisers (n = 103, 52 women) or nonexercisers (n = 101, 51 women), completed a questionnaire and then rated their interest using images of cereal bars that varied in four characteristics ("With fruit," "With chocolate," "High protein," and calorie content). Conjoint analysis showed that the most important motives were associated with the convenience, pleasure/indulgence and liking dimensions, which did not differ between groups. These were followed by two other motives introduced in this study: energy/physical activity and satiety, in which the exercisers showed a distinctively higher level of interest than the nonexercisers. Chocolate and a low calorie content were the outstanding drivers of interest, at similar levels for both groups. A high protein content claim increased the interest of all participants, but more so for exercisers and for men. Fruit had a low impact on interest, which was only significant for women. These results indicate that front-of-pack label information influences choice in a distinctive way for some targeted population groups. PRACTICAL APPLICATION: This study contributes knowledge about the impact that front-of-pack label information about certain ingredients and the energy content has on the motives and drivers for snack choices and perceptions of healthiness. The results contribute interesting results on the behavior of some consumer segments, in particular, exercisers and people involved in fitness activities, who are supposed to have special dietary needs.


Assuntos
Comportamento de Escolha , Rotulagem de Alimentos , Percepção , Lanches/psicologia , Adolescente , Adulto , Comportamento do Consumidor , Grão Comestível/química , Grão Comestível/metabolismo , Ingestão de Energia , Feminino , Ingredientes de Alimentos/análise , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
5.
Rev. colomb. quím. (Bogotá) ; 40(2): 149-164, mayo.-ago. 2011.
Artigo em Espanhol | LILACS | ID: lil-636713

RESUMO

Se preparó una serie de películas de quitosano-gelatina variando la relación de los constituyentes, quitosano-gelatina entre 1:2, 1:5 y 1:10, con concentración total de biopolímeros entre 3,0%, 3,5%, 4,0% y pH de 5,5. Se deshidrataron los soportes por crioconcentración (congelaciones descongelaciones sucesivas) y secado convectivo con aire. La inmovilización de lipasa de Candida antarctica se realizó sobre un hidrogel entrecruzado iónicamente con quitosano por atrapamiento y por adsorción; los mejores resultados en cuanto a actividad enzimática y reutilización del soporte se obtuvieron con el método por atrapamiento. Se llevaron a cabo pruebas de caracterización fisicoquímica de los soportes, actividad del sistema biocatalítico y estabilidad.


A set of chitosan-gelatin films were prepared by varying the chitosan-gelatin ratio between 1:2, 1:5 and 1:10, with total concentration of biopolymers from 3,0% 3,5%, 4,0 and pH of 5,5. We carried out the dehydration of the supports through cryoconcentration (successive freeze thawing) and convective drying with air. Immobilization of lipase from Candida antarctica was performed on an ionically crosslinked hydrogel with chitosan by entrapment and adsorption, getting the best results in terms of enzymatic activity and reuse of the support with the entrapment method. Tests of physicochemical characterization of the supports, biocatalytic system activity and stability were carried out.


Uma serie de filmes de gelatina quitosana foi preparada variando a proporção dos componentes, a quitosana-gelatina entre 01:02, 01:05 e 01:10, com concentração total de biopolímeros de 3,0%, 3,5% 4,0% e pH de 5,5. Realizou-se a desidratação dos suportes por crioconcentração (ciclos sucessivos de descongelamento-congelamento) e secagem por convecção com o ar. A imobilização de lipase de Candida antarctica foi realizada em um hidrogel ionicamente entrecruzado com quitosana por adsorção e atrapamento, obtendo os melhores resultados em termos de atividade enzimática e reutilização do suporte com o método de atrapamento. Foram realizados testes de caracterização físico-química dos suportes, da atividade do sistema biocatalítico e da estabilidade.

6.
Bioprocess Biosyst Eng ; 32(2): 197-206, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18546023

RESUMO

When gelification is performed by freezing-thawing repeated cycles, the resultant gel-like polymer systems are called cryogels. This work aims to assess the effect of the addition of glutaraldehyde and 18 Crown Ether-6 on surface properties and protein loading of dried chitosan cryogel films. Residual water content of treated chitosan membranes ranged between 11.93 and 13.86%, while their water activities vary from 0.5 to 0.7 (measured from 4 to 60 degrees C). Based on thermal data, water evaporation peak and degradation temperatures of chitosan membranes shifted to a higher temperature for crosslinked samples. X-ray diffractograms provide high values of crystallinity for all the samples (70.67-92.86%), the highest value being for the glutaraldehyde-treated membrane. Candida rugosa lipase can be immobilized successfully on chitosan membranes. Lipase immobilized on glutaraldehyde-crosslinked chitosan yielded the highest efficiency in terms of total coupled protein and protein loading efficiency.


Assuntos
Quitosana/química , Géis , Membranas Artificiais , Varredura Diferencial de Calorimetria , Candida/enzimologia , Congelamento , Lipase/química , Microscopia de Força Atômica , Difração de Raios X
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