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1.
Foods ; 12(16)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37628068

RESUMO

Chocolate is a confectionery product whose consumption has increased, particularly dark chocolate. Chocolate is produced with varying amounts of cocoa liquor (CL), cocoa butter (CB) and cocoa powder (CP). The main chocolate types are dark, milk and white. Processing steps for chocolate production are described, and nutritional compositions examined for benefits and risks to health. Chocolate processing comprises steps at farm level, initial industrial processing for production of CL, CB and CP (common for all chocolate types) and mixing with other ingredients (like milk and sugar differing according to chocolate type) for industrial chocolate processing. All chocolate types present similar processing levels, and none involve chemical processing. Nutritional profiles of chocolate products differ according to composition, e.g., dark chocolate contains more CL, and so a higher antioxidant capacity. Chocolate is an energy-dense food rich in bioactive compounds (polyphenols, alkaloids, amino acids). Studies have demonstrated benefits of moderate consumption in reducing cardiovascular risk and oxidative and inflammatory burden, improving cognitive functions, maintaining diversity in gut microbiota, among others. In our view, chocolate should not be classified as an ultra-processed food because of simple processing steps, limited ingredients, and being an important part of a healthy diet when consumed in moderation.

2.
Int J Biol Macromol ; 164: 1399-1412, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32763389

RESUMO

Biodegradation tests of chitosan (CH), polybutylene adipate terephthalate (PBAT) and high density polyethylene (HDPE) polymers were carried out using the standard OECD 301D guidelines. The results showed that the CH samples biodegraded faster than those of PBAT. Photographs registered exhibited the complete or partial disintegration of the samples, and a more opaque color was observed with the increase of biodegradation. FTIR analysis showed some changes in the intensity of the typical bands of the HDPE sample. The presence of P. nitroreducens bacteria was revealed on the PBAT sample surface by SEM studies. Additionally, a clear increase in elastic modulus (EM) and tensile strength (TS) values were observed in PBAT and HDPE samples on day 3, which decreased significantly at the end of the study. Furthermore, an increase in the crystallinity of the HDPE sample was observed on day 28.


Assuntos
Biodegradação Ambiental , Quitosana/química , Poliésteres/química , Polietileno/química , Polímeros/química , Adipatos , Módulo de Elasticidade , Teste de Materiais , Microscopia Eletrônica de Varredura , Peso Molecular , Nanocompostos , Oxigênio/química , Pressão , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Resistência à Tração
3.
Heliyon ; 6(4): e03809, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32382679

RESUMO

Food packaging materials are commonly derived from petroleum that increases global contamination; this raises the interest to evaluate raw material from renewable sources such as whey protein for the development of packaging materials, especially to produce active films. This research aimed to evaluate whey protein-based film properties when natamycin, nanoemulsioned α-tocopherol, or both were added. An oil-in-water (O/W) nanoemulsion of antioxidant (α-tocopherol) was prepared by microfluidization technique. Four films were prepared with different levels of natamycin and nanoemulsified α-tocopherol and were characterized in terms of physicochemical, mechanical, optical-properties, water vapor barrier, FTIR, microstructure, antioxidant and antimicrobial activity. The natamycin, nanoemulsified α-tocopherol, or both did not modify the moisture content of the films. Moreover lead to a significant reduction of tensile strength and elastic modulus, while presenting growth in the elongation at break. Film opacity, the total color difference, the UV-Vis light barrier, and the water vapor permeability values increased when compounds were incorporated into the film. The microstructure studies showed uniformly distributed porosity throughout the films. The addition of nanoemulsioned α-tocopherol into whey protein-based films provoked antioxidant activity and the addition of natamycin produced films with effectivity against C. albicans, P. chrysogenum, and S. cerevisiae, allowing develop a material appropriate for use as active food packaging.

4.
Int J Biol Macromol ; 151: 178-185, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32044371

RESUMO

Biodegradable films based on pure gelatin (GEL100), chitosan (CH100) and sodium caseinate (SCas100), and gelatin-chitosan (GEL50:CH50) and gelatin­sodium caseinate (GEL50:SCas50) blends, without or with boldo-of-Chile leafs extract (BoC) were studied. The solubility in water (%) of all the pure films was analyzed. Moreover, the disintegration process was evaluated throughout the mass loss (%), structural (FTIR) changes and visual analyses of films up to 5 days of composting conditions. The Boltzmann function allowed obtaining the half-maximal disintegration time (t50) of all the films. Only Scas100 films exhibited complete solubility in water, compared to the other films (P < 0.05). At day 1, SCas100 + B film exhibited total mass loss, meanwhile for the other film samples this parameter varied between 47.9 ± 3.0% (CH100 + B) and 6.8 ± 1.3% (GEL100 + B) (P < 0.05). FTIR analysis showed some changes in the intensity of the typical bands of the pure or blended films. Photographs registered exhibited the complete disintegration of all films into 5 days. Finally, Boltzmann equation displayed that pure SCas100 film disintegrated in the shortest time (0.500 days), and GEL50:CH50 blended film in the longest time (1.766 days). In conclusion, the results of this work show an appropriate and complete disintegration of all studied films in composting conditions.


Assuntos
Caseínas/química , Quitosana/química , Gelatina/química , Extratos Vegetais/química , Biopolímeros/química , Fenômenos Químicos , Folhas de Planta/química , Sensibilidade e Especificidade , Solubilidade , Análise Espectral , Água/química
5.
J Biotechnol ; 231: 232-238, 2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27316828

RESUMO

Agro-industrial waste can be the production source of biopolymers such as polyhydroxyalkanoates. The aim of this study was to produce and characterize Polyhydroxyalkanoates produced from pineapple peel waste fermentation processes. The methodology includes different pineapple peel waste fermentation conditions. The produced biopolymer was characterized using FTIR, GC-MS and NMR. The best fermentation condition for biopolymer production was obtained using pH 9, Carbon/Nitrogen 11, carbon/phosphorus 6 and fermentation time of 60h. FTIR analyzes showed PHB group characteristics, such as OH, CH and CO. In addition, GC-MS showed two monomers with 4 and 8 carbons, referred to PHB and PHBHV. H(1) NMR analysis showed 0.88-0.97 and 5.27ppm signals, corresponding to CH3 and CH, respectively. In conclusion, polyhydroxyalkanoate production from pineapple peels waste is an alternative for the treatment of waste generated in Colombia's fruit industry.


Assuntos
Ananas/química , Cupriavidus necator/metabolismo , Poli-Hidroxialcanoatos/química , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Resíduos Industriais , Ressonância Magnética Nuclear Biomolecular , Poli-Hidroxialcanoatos/análise , Espectroscopia de Infravermelho com Transformada de Fourier
6.
J Sci Food Agric ; 90(7): 1185-93, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20394000

RESUMO

BACKGROUND: Amaranth is a little-known culture in Brazilian agriculture. Amaranthus cruentus BRS Alegria was the first cultivar recommended by Embrapa for the soil of the Brazilian scrubland. In order to evaluate the potential of this species in the production of flour, starch and protein concentrates, the latter products were obtained from A. cruentus BRS Alegria seeds, characterized and compared with the products obtained from the A. caudatus species cultivated in its soil of origin. RESULTS: The seeds of A. cruentus BRS Alegria furnished high-purity starch and flour with significant content of starch, proteins, and lipids. The starch and flour of this species presented higher gelatinization temperatures and formed stronger gels upon cooling compared with those obtained from the A. caudatus species. This is due to their greater amylose content and a difference in the composition of the more important fatty acids, such as stearic, oleic and linoleic acids, which indicates that they have greater heat stability. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and differential scanning calorimetry revealed the presence of albumins, globulins, glutelins and prolamins in the protein concentrate, which was obtained as a byproduct of starch production. CONCLUSION: Amaranthus cruentus BRS Alegria has potential application in the production of flour, starch and protein concentrates, with interesting characteristics for use as food ingredients.


Assuntos
Amaranthus/química , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Farinha , Proteínas de Plantas/análise , Sementes/química , Amido/química , Albuminas/análise , Amilose/análise , Ácidos Graxos/análise , Farinha/normas , Géis , Globulinas/análise , Glutens/análise , Temperatura Alta , Prolaminas/análise , Reologia , Sementes/genética , Amido/normas
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