Physicochemical, thermal, mechanical, optical, and barrier characterization of chia (Salvia hispanica L.) mucilage‐protein concentrate biodegradable films

Abstract

In this study, the effect of chia mucilage (CM) and protein concentrate (CPC) contents on the physicochemical, thermal, mechanical, and optical characteristics of developed films was evaluated. Films were prepared dissolving CM:CPC mixtures (1% w/v) in seven ratios (0:1, 1:4, 1:2, 1:1, 2:1, 4:1, 1:0). Microstructure of treatments with higher CM revealed the formation of polysaccharide granules. A semicrystalline behavior was manifested in 1:0, which decreased as CPC content in the formulations increased. Contact angle values obtained for 1:1 and 2:1 were the highest (61.24°and 62.44°), evidencing less affinity to water than other films. TGA analysis suggest that films showed thermal stability at less than 225°C. Melting temperatures above 85°C were found for all films in the evaluated range (50°C to 200°C) of DSC analysis. Higher CM concentrations in films increased the force required to break them (13.5 MPa) and their elongation capacity (5.20%). As the CM ratio in formulations was increased, the color difference was lower ( E = 27.45), water vapor permeability was higher (10.9 × 10 −11 g/m·s·Pa), but transparency was statistically the same for all treatments (6.62 to 7.26). After analyzing all films properties, 2:1 formulation corresponding to 25:75% w/v mixtures of CM:CPC would be the best option for use in food packaging.

Anticancer activity of protein fractions from chia (Salvia hispanica L.)

“…The protein content of the degummed and defatted flour obtained from S. hispanica seeds was 75.28 ± 1.08%. The percentage obtained in the present study is higher than the percentage reported by Salazar et al (2020), who despite obtaining a protein concentrate had a lower protein content (40.5 ± 0.5%), probably attributed to differences in the degumming procedure and the additional defatting steps performed in the present study.…”

“…The method reported by Salazar et al. (2020) was followed with some adjustments. The mucilage was extracted by preparing a suspension with whole seeds and distilled water in a 1:40 (w/v) proportion.…”

Use of Chia by-Products Obtained from the Extraction of Seeds Oil for the Development of New Biodegradable Films for the Agri-Food Industry

“…The films formed with defatted flour showed lower thickness than films made with chia flour by Dick et al [23] due to the different amounts of CM used in the film formation. The thickness of films made with whole seeds was consistent with those obtained by Muñoz et al [28] and Salazar Vega et al [29] in films made with whole chia seeds. Moreover, comparing the thickness of both films with other polysaccharide films, it was noticed that the values were slightly higher (0.09-0.012 vs. 0.07-0.08 mm) than films made with cress seed gum [30], psyllium seed [31], Balangu seed mucilage [32], and chitosan [26].…”

“…Thickness determines the technological properties of the films, so its control plays an important role. It has been observed that the main factors modifying film thickness are the amount of plasticizer added to the film [18] and the amount of coating cast [23,29]. Likewise, for its industrial application as a coatings/film, the factors to consider are the immersion time and the number of times the food is immersed.…”

Chia protein hydrolysates: characterisation and emulsifying properties

“…A chia protein concentrate (CPC) was obtained according to Salazar-Vega et al (2020). After the CM extraction, the residual seed material was ground with a laboratory Thomas-Wiley mill (Model 4, Thomas Scientific, USA) and subjected to lipid extraction with n-hexane.…”