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Plantain bananas of the variety ''Terra'' (Musa paradisiaca) may have industrial value due to their high starch content. In this research, the flour and starch of such unripe fruit were isolated and their chemical, physicochemical, and structural characteristics were determined. Banana flour and starch had a dry basis yield of 50.6 and 28.5%, and an average granule size of 31.7 and 47.3 mm, respectively. Both raw materials revealed a C-type pattern and high gelatinization temperatures.

Cellulose nanofibers were isolated from banana peel using a combination of chemical and mechanical treatments with different number of passages through the high-pressure homogenizer (0, 3, 5, and 7 passages). New nanocomposites were then prepared from a mixed suspension of banana starch and cellulose nanofibers using the casting method and the effect of the addition of these nanofibers on the properties of the resulting nanocomposites was investigated. The cellulose nanofibers homogeneously dispersed in the starch matrix increased the glass transition temperature, due to the strong intermolecular interactions occurring between the starch and cellulose. The nanocomposites exhibited significantly increased the tensile strength, Young's modulus, water-resistance, opacity, and crystallinity as the number of passages through the homogenizer augmented. However, a more drastic mechanical treatment (seven passages) caused defects in nanofibers, deteriorating the nanocomposite properties. The most suitable mechanical treatment condition for the preparation of cellulose nanofibers and the corresponding nanocomposite was five passages through the high-pressure homogenizer. In general, the cellulose nanofibers improved the features of the starch-based material and are potentially applicable as reinforcing elements in a variety of polymer composites.

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The present study evaluated the effect of using electrospun polycaprolactone (PCL) as a barrier coating and black pepper oleoresin (OR) as a natural extract on the morphology, thermal, mechanical, antimicrobial, oxygen, and water vapor barrier properties of solvent cast gelatin (GEL). The antimicrobial activity of the developed multilayer system obtained by the so-called electrospinning coating technique was also evaluated against Staphylococcus aureus strains for 10 days. The results showed that the multilayer system containing PCL and OR increased the thermal resistance, elongated the GEL film, and significantly diminished its permeance to water vapor. Active multilayer systems stored in hermetically closed bottles increased their antimicrobial activity after 10 days by inhibiting the growth of Staphylococcus aureus. This study demonstrates that addition of electrospun PCL ultrathin fibers and OR improved the properties of GEL films, which promoted its potential use in active food packaging applications.

Achira (Canna indica L.) is a plant native to the Andes in South America, a starchy source, and its cultivation has expanded to different tropical countries, like Brazil. In order to evaluate the potential of this species, starch and flours with different particle size were obtained from Brazilian achira rhizomes. Proximal analyses, size distribution, SEM, swelling power, solubility, DSC, XRD analysis, and FTIR were performed for characterization of these materials. Flours showed high dietary fiber content (16.5-32.2% db) and high concentration of starch in the case of the smaller particle size fraction. Significant differences in protein and starch content, swelling power, solubility, and thermal properties were observed between the Brazilian and the Colombian starch. All the studied materials displayed the B-type XRD pattern with relative crystallinity of 20.1% for the flour and between 27.0 and 28.0% for the starches. Results showed that the starch and flour produced from achira rhizomes have great technological potential for use as functional ingredient in the food industry.

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This study focused on the development of gelatin-based films with incorporation of microcrystalline cellulose as reinforcement material. Clove (Syzygium aromaticum), nutmeg (Myristica fragrans), and black pepper (Piper nigrum) oleoresins containing antimicrobial compounds of natural origin were incorporated into the films. The mechanical, thermal, optical, and structural properties, as well as color, seal strength and permeability to water vapor, light, and oil of the films were determined. Adding oleoresins to the gelatin matrix increased the elongation of the material and significantly diminished its permeability to water vapor and oil. Evaluation of the potential use of films containing different oleoresins as bread packaging material was influenced by the film properties. The biocomposite film containing oleoresin from black pepper was the most effective packaging material for maintaining bread’s quality characteristics.