Films of PBAT/TPS (poly(butylene adipate-co-terephthalate)/thermoplastic starch) (starch plasticized with glycerol containing citric and stearic acids) without and with 0.6 wt% starch nanoparticles were produced by extrusion. The presence of nanoparticles during the extrusion process led to a higher degree of starch gelatinization improving starch compatibility with PBAT. Nanoparticles modified the interaction between the different components of the PBAT/TPS composite. The hydroxyl groups of the starch nanoparticles interacted with starch amylose by means of hydrogen bonds. In addition, nanoparticles modified the structure of the PBAT rigid segment (BT): a shift of T m of BT toward lower temperatures and a slight shift of the relaxation of the BT segment to higher temperatures were observed. The incorporation of nanoparticles also had a reinforcing effect on the PBAT/TPS matrix. The composite presented slight increases of Young's modulus (E) and stress at break ( b ) without affecting the strain at break ( b ). The rate of biodegradability was improved with the use of starch nanoparticles. The composite showed faster deterioration than the matrix, showing the first changes in its tonality and breakdowns at only 6 days of burial in compost.

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Active packaging can be defined as packaging that includes additives that help to extend the shelf life of food; among the advantages of its use is the possibility to reduce the amount of additives added to the food during processing. The aim of this study was to develop, characterize, and apply active films of low‐density polyethylene, incorporating carotenoid and yerba mate extracts as active additives. Active films were obtained by extrusion and were characterized for water vapor permeability, thickness, color, and mechanical and thermal properties. The effectiveness of the films was evaluated using butter packed in the formulated films. There was a significant reduction in thickness, and mechanical, thermal, and water vapor barrier parameters of the films compared to the control. The concentration of additives directly influenced coloration and antioxidant and antimicrobial action of the films. The formulated films provided protection against oxidative action and inhibition of microbial growth. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46461.

The aim of this study was the physicochemical characterization of traditional cassava flours from Copioba Valley in Reconcavo Baiano (Northeast Brazil). Samples were collected in flour houses and analyzed by official methods of proximate composition and chromatography and spectroscopy for fatty acids and volatile compounds. Regardless of geographical origin (inside and outside the Valley) and processing type (Copioba and Common flour), there were no significant differences in water activity, ash, crude protein, starch, carbohydrates or acidity. By contrast, significant differences were observed in moisture, particle size, total lipids, palmitic acid and volatile compounds, mainly nonanal. Discriminant classification by principal component analysis according to origin and processing was obtained using this differentiation. These parameters are important for associations of reputation, authenticity and differentiation with the Protected Geographical Indication of Copioba cassava flours.