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Cellulose at the nanoparticle scale has been studied as a reinforcement for biodegradable matrices to improve film properties. The goal has been to investigate the properties of starch/gelatin/cellulose nanocrystals (CNC) films. Eleven treatments were considered using RCCD (rotatable central composite design), in addition to four control treatments. For each assay, the following dependent variables were measured: water vapor permeability (WVP), thickness, opacity and mechanical properties. The microstructure and thermal properties of the films were also assessed. Increases in gelatin and CNC concentrations lead to increases in film thickness, strength and elongation at break. The films containing only gelatin in their matrix displayed better results than the starch films, and the addition of CNC had a positive effect on the assessed response variables. The films exhibited homogeneous and cohesive structures, indicating strong interactions between the filler and matrix. Films with low levels of gelatin and CNC presented the maximum degradation temperature.

The objective of the present study was to evaluate lignocellulosic particles from sub-products of the coffee industry (coffee parchment -CP and husk -CH) into polyhydroxybutyrate (PHB) as a promising reinforcing filler in the biocomposites. The effects of type (CP or CH) and content (neat, 10% and 20%) of coffee wastes on the thermal, mechanical, microstructural and physical properties of the ensuing composites were evaluated. Thermal stability of the composites was improved by the coffee residues at different contents, while degree of crystallinity was decreased with the inclusion of CP. The addition of 10% of CP has not influenced significantly the tensile strength (TS) and Izod strength (IS), in relation to the neat PHB. Tensile strength (TS), MOE and Izod strength (IS) of the composites have increased significantly with the inclusion of 20% of CP. The increase in the content of coffee waste particles increased the water absorption of the composites.

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RESUMOObjetivou-se com este trabalho foi avaliar três marcas de diferentes sucos de uva integral (Vitis labrusca L.) oriundos de duas regiões do Brasil (Sudeste e Centro-Oeste). Os sucos foram avaliados quanto às seguintes análises: sólidos solúveis (°Brix), acidez titulável (AT), pH, vitamina C, açúcares redutores, totais e não-redutores. Os resultados indicaram variabilidade entre as diferentes marcas de sucos de uva, evidenciando que estas encontram-se fora dos padrões estabelecidos pela legislação brasileira em vigor. De acordo com os elevados valores de açúcares totais e não redutores, pode-se inferir que houve adição de sacarose nas três marcas dos sucos analisados.Termos para indexação: Suco de uva, vitamina C, composição. ABSTRACTThe purpose of this work was to evaluated three different marks of juice of integral grape (Vitis labrusca L.) originating from two regions of Brazil (Southeast and Center-west). The juices had been evaluated as the following analyses: soluble solids (ºBrix), titratable acidity (AT), pH, vitamin C, reducing sugars, total and no-reducing sugars. The results indicated variability among the differents marks of grape juice, showing that they find themselves out of the established patterns by the vigorating Brazilian legislation. Acording to the high values of total and non reducing sugars, it may be inferred that there was addition of sucrose in the three analyzed juice marks.

e aim of this study was to develop a chitosan/cellulose nano bril (CNF) nanocomposite and evaluate its e ect on strawberry's postharvest quality after coating. From the results of color, thickness, and scanning electron microscopy (SEM) and permeability to water vapor analyses, the best lm formulation for coating strawberries was determined. ree coating formulations were prepared: 1% chitosan, 1% chitosan + 3% CNF, and 1% chitosan + 5% CNF. e strawberries were immersed in the lmogenic solutions and kept under cold storage (1 ± 1°C). e color of the lm was not a ected by increased concentration of cellulose nano brils; however, the thickness and water vapor permeability were a ected by the CNF addition. e coating with the highest CNF concentration performed better in reducing fruit mass and rmness loss. e color was positively in uenced by the addition of the coating, regardless of formulation, as well as soluble solid content, PG enzymatic activity, and the fruit appearance. e pH and titratable acidity showed no signi cant di erence among treatments. It was observed that the vitamin C, phenolic compounds, and anthocyanin content, as well as the PAL activity and the antioxidant activity (except for % protection), were a ected by chitosan coating, however not by the addition of CNFs.

RESUMOConduziu-se o presente trabalho para estudar o efeito de diferentes sanificantes, na conservação pós-colheita de morangos, armazenados sob refrigeração (9± 1ºC e 99% UR), por um período de 12 dias. O delineamento experimental utilizado foi inteiramente casualizado, com 3 repetições, constituindo dos seguintes tratamentos: T1) Controle, imersão em água destilada, 15 min, T2) imersão em solução de dicloro s. triazinatriona sódica dihidratada (Sumaveg®) a 200 ppm, por 15 min; T3) imersão em solução de peróxido de hidrogênio 10%, por 15 min; T4) imersão em solução de dicloro isocianurato de sódio (Hidrosan®) a 200 ppm, por 15 min. As análises de pH, SS, AT, Cor L*a*b e microbiológicas foram realizadas a cada 3 dias. Os processos de sanificação adotados foram eficientes para manter a qualidade de morangos minimamente processados por 12 dias de armazenamento. Verificou-se, no presente trabalho, que o uso de sanificantes foi de fundamental importância para manter baixas as contagens de fungos filamentosos e leveduras dos morangos minimamente processados. Termos para indexação:Fragaria ananassa Duch., Pós-Colheita, Sanificante, Armazenamento. ABSTRACTThe aim of this work was to study the effect of different sanitizing in the conservation postharvest of strawberry, stored in 9°C and 99% R.H. for 12 days. The experiment was conducted in completely randomized design, with three replicates, the treatments constituted by: T1) Control, immersion in distilled water; T2) immersion in solution of dychlorine s. triazinatriona sodiumdehydrated (Sumaveg®) at 200 ppm, for 15 min; T3) immersion in solution of hydrogen peroxide 10%, for 15 min; T4) immersion in solution of dychlorine isocianurate of sodium (Hidrosan®) 200 ppm, for 15 min. The analyses of pH, SS (soluble solids), TA (titrable acidity), Color L*a*b and microbiological was evaluated in 0, 3, 6, 9 and 12 days. The process of sanitizing was efficient to maintain the quality of strawberry minimally processed for 12 days. The use of sanitizing was of fundamental importance to maintain low containing of microorganisms of the group mold and yeasts.

This work extends the method to follow in real time the reduction of the clay particle size by light extinction measurements (turbidity), obtained via an in‐line optical detector fitted at the extruder die exit, to monitor multiple extrusions of PP/MMT nanocomposites. The optical detector was calibrated and showed to follow the Mie Theory. This theory states that the transmitted light intensity decreases for suspension of particles smaller than 500 nm. Corroborating with these results, off‐line color measurements has shown that the luminosity decrease and the yellow color increases during multiple extrusions of the nanocomposites. In addition, the color difference and the yellowness indexes of the nanocomposites using organic modified montmorillonite (MMT) are higher then the MMT Na+ (sodium MMT) after multiple extrusions. The addition of clay to a PP matrix produced an increase in the opacity. Results from X‐ray do follow the same trend as those obtained from the in‐line light extinction measurements. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers