RESUMO
Biodegradable starch foam trays offer an eco-friendly substitute for petroleum-based single-use packaging, notably polystyrene foams. However, they lack flexibility, tensile strength, and water-sensitivity, addressable through lignocellulosic reinforcement. This study aimed to develop biodegradable starch foam trays filled with different food-chain side streams for sustainable alternative packaging. Corncob, soybean straw, cassava peel, araucaria seed hull, yerba mate stalks and yerba mate leaves petiole were collected, dried and ground to <250 µm. The trays were filled with 13 % (w/w) of each food-chain side streams and produced by hot molding. The trays morphology, moisture, water activity (aw), thickness, bulk density, tensile strength, elongation at break, Young's modulus, bending strength, maximum deflection, and sorption isotherms were investigated. Reinforcements slightly increased the foams bulk density, reduced the tensile strength and maximum deflection and while bending strength increased from 0.20 MPa to 1.17-1.80 MPa. The elasticity modulus decreased by adding any filling, that resulted in ductility improvement; however, these packaging have moisture-sensitive material especially for aw higher than 0.52, which drives the use recommendation for dry products storage or shipping/transport. The biodegradable starch foam trays filled with side streams were successfully produced and offer excellent alternative to petroleum-based packaging low-density material with bending strength improved.
Assuntos
Amido , Resistência à Tração , Amido/química , Água/química , Embalagem de Alimentos/métodos , Manihot/químicaRESUMO
Ilex paraguariensis is a native tree from South America known for the presence of bioactive compounds, and its processed leaves are consumed as hot and cold infusions. After harvest (step 1), the leaves are subjected to flame blanching to inactive the enzymes (step 2), followed by drying and milling (step 3). The impacts of I. paraguariensis processing on leaf composition were investigated by extracting the major compounds (chlorogenic and isochlorogenic acids (3-CQA, 4-CQA, 5-CQA, 3,4-DQA, 3,5-DQA and 4,5-DQA), p-coumaric acid, caffeine and rutin) using different ratios of ethanol and water as extraction solvent (EW 25:75, 50:50, and 75:25 (w/w)). The solvent ratio of EW 50:50 was more effective in extracting the chlorogenic acids isomers, with retention of chlorogenic acids of 3463, 9485, and 9516 µg mL- 1 for steps 1, 2, and 3, respectively. Rutin and p-coumaric acid exhibited similar behavior with the increment of processing steps; however, p-coumaric acid was only detected in steps 2 and 3 for the solvent ratios EW 50:50 and 25:50. The caffeine extraction from I. paraguariensis varied from 936 to 1170 µg mL- 1 for all processing steps, with emphasis on its concentration extracted in step 1. The evolution of processing steps led to a higher retention of phenolic compounds from I. paraguariensis, which was not observed when using different solvent ratios, and the solvent ratio EW 50:50 was more effective for the extraction of chlorogenic acids. The successful extraction of chlorogenic acids from I. paraguariensis in this study proved to be a promising alternative for the use of yerba mate beyond the cuia cup.
Assuntos
Ilex paraguariensis , Cafeína , Extratos Vegetais , Rutina , SolventesRESUMO
The yerba mate (Ilex paraguariensis A.St.-Hil.) is abundant on phenolic compounds and their preservation by encapsulation can promote increased stability. The objective was to produce mate extract with a high concentration of bioactive compounds, microencapsulate and characterize them. A commercial yerba mate was used to produce the extracts and select the best extraction solvent (ethanol, water, and ethanol:water (1:1). The ethanol:water extract was encapsulated at 1:1 (w/w) by fructooligosaccharide (FOS) and gum arabic (GA), in different combinations: FOS, GA:FOS (1:3), GA:FOS (1:1), GA:FOS (3:1) and GA. The encapsulation of chlorogenic acids was around 80%, considering the major phenolic compounds by HPLC. Thermal stability, by DSC, increased at treatments FOS, GA:FOS (1:3), and GA:FOS (1:1) compare to the unencapsulated extract, and changes were noticed in ATR-FTIR bands and antioxidant activity. The encapsulated phenolic compounds from I. paraguariensis can be stable in food under heat processing.