EQA - Escola de Química e Alimentos
URI permanente desta comunidadehttps://rihomolog.furg.br/handle/1/1610
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4 resultados
Resultados da Pesquisa
- ItemUsing edible coatings fromWhitemouth croaker (Micropogonias furnieri) protein isolate and organo-clay nanocomposite for improve the conservation properties of fresh-cut ‘Formosa’ papaya(Elsevier, 2014) Cortez-Vega, William Renzo; Pizato, Sandriane; Souza, Juliana Tais Andreghetto de; Prentice-Hernández, CarlosEdible coatings have been used in the fresh-cut industry as a strategy to reduce the deleterious effects of minimal processing on plant tissues. The objective of this study was to apply edible coatings from protein isolate of Whitemouth croaker with organo-clay montmorillonite in minimally processed papaya slices, throughout the storage of 12 days at 5 °C, and assess their properties and verify the effectiveness of this coating as a barrier against theweight loss of papaya, aiming to increase its shelf-life. The different coatings appliedwith andwithout montmorillonite in minimally processed papaya were effective during the 12 days of storage. The croaker protein isolate (CPI) and montmorillonite (MMT) coating applied to minimally processed papaya showed lower mass loss (5.26%), lower microbial growth and a smaller decrease of firmness, lightness and pH, and therefore showed the best results in coating of minimally processed papaya. Industrial relevance: Papaya is verymuch appreciated in its minimally processed, but this type of processing causes injuries so that its shelf-life is reduced. This perishability of papaya needs a good preservation strategy. The present results demonstrated the feasibility of using edible coatings on the basis of fish protein isolate and organo-clay nanocomposite, with low cost and high shelf-life compared to the control sample. The study further confirms that the viability of fish protein of low value for the industries becomes a great potential to increase the shelflife of minimally processed papaya, without changing the characteristics in relation to odor and appearance of minimally processed fruit.
- ItemBiofilmes nanocompósitos obtidos de isolado proteico de corvina (Micropogonias furnieri) e Montmorilonita: avaliação das propriedades físicas, mecânicas e de barreira(2013) Cortez-Vega, William Renzo; Bagatini, Daniela Cardozo; Souza, Juliana Tais Andreghetto de; Prentice-Hernández, CarlosO objetivo deste trabalho foi avaliar as propriedades de biofilmes nanocompósitos de isolado proteico de corvina (Micropogonias furnieri) com argila organofílica. Inicialmente, foi obtido isolado proteico de corvina (IPC) utilizando-se o processo de mudança de pH. O IPC foi obtido a partir de subprodutos da industrialização de corvina. Para o desenvolvimento dos filmes, foi executado um planejamento experimental de Box e Behnken, com três níveis de IPC (2; 3,5; 5 g.100 g–1 de solução), argila montmorilonita MMT (0,3; 0,5; 0,7 g.100 g–1 de solução) e glicerol (25, 30, 35 g.100 g–1 IPC). Os filmes poliméricos foram desenvolvidos pela técnica de casting. Os valores de resistência à tração variaram entre 7,2 e 10,7 MPa, e os valores de alongamento, de 39,6 a 45,8%. Os valores de permeabilidade ao vapor de água (PVA) variaram entre 3,2 e 5,5 g mm m–2 d–1kPa–1. O IPC apresentou teor médio de proteína de 97,87% (b. s.). Pode-se concluir que os filmes nanocompósitos produzidos a partir de IPC com MMT foram promissores, desde o ponto de vista das propriedades mecânicas, da aparência visual e do fácil manuseio até a baixa permeabilidade ao vapor de água e a baixa solubilidade. Com relação às propriedades mecânicas, as concentrações de IPC e MMT foram os principais fatores que influenciaram o desenvolvimento dos filmes nanocompósitos. Os resultados obtidos no planejamento experimental utilizado indicaram que 3,5 g de IPC.100 g–1 de solução, 0,5 g de MMT.100 g–1 de solução e 30 g de glicerol.100 g–1 IPC seriam os parâmetros ideais para a preparação de filmes nanocompósitos por casting.
- ItemInfluence of heating, protein and glycerol concentrations of film-forming solution on the film properties of Argentine anchovy (Engraulis anchoita) protein isolate(2013) Rocha, Meritaine da; Loiko, Márcia Regina; Gautério, Gabrielle Victoria; Tondo, Eduardo César; Prentice-Hernández, CarlosThis study was conducted to evaluate the influence of thermal treatment (74, 82, and 90 _C), glycerol (30%, 35%, and 40%, w/w) and protein concentrations (3.0%, 3.5%, and 4.0% w/w) of film-forming solution on the properties of Argentine anchovy (Engraulis anchoita) protein isolate (API) films produced by casting. The API presented 88.8% of proteins, 5.5% moisture, 1.3% lipids, 1.0% ash and 53.3% of polar amino acids. The DSC of protein isolate was observed at maximum temperature of 62.2 _C and DH 6.4 J/g. The thickness, water vapor permeability, color difference and opacity of the films were not affected by the experimental variables studied (p > 0.05). The lowest solubility, elongation, and highest tensile strength of the films occurred at low temperature, low protein and glycerol concentrations (p < 0.05). Micrographs obtained by scanning electron microscopy of the films showed homogeneous surfaces at low temperature.
- ItemChemical modification and structural analysis of protein isolates to produce hydrogel using whitemouth croaker (micropogonias furnieri) wastes(2011) Martins, Vilásia Guimarães; Costa, Jorge Alberto Vieira; Damodaran, Srinivasan; Prentice-Hernández, CarlosRecovery and alteration of fish protein from wastes and its use has been regarded as a promising alternative to develop useful products once polymer gels have a high capacity of water uptake. This study aims to produce hydrogel, a super absorbent biopolymer from modified fish protein, in order to evaluate the protein structure. In the modified proteins, analyses of the extent of modification of the lysine residues, electrophoresis, and electrometric titration were performed. In the hydrogels were realized assays of swelling water. The proteins with more modifications were shown as 63.5% and 75.9% of lysine residues, from fish protein isolate obtained with alkaline and acid solubilization, respectively. The modified protein in that same rate presented 332.0 and 311.4 carboxyl groups. Accordingly, the hydrogel produced from alkaline and acid isolates reached a maximum water uptake in 24 h of 79.42 and 103.25 gwater/gdry gel, respectively.