The objective of this study was to develop and characterize cassava-starch-based films incorporated with buriti (Mauritia flexuosa L.) oil and emulsifier (Tween 20). An experimental factorial design 22 with three central points was used to develop the films, by varying the concentrations of buriti oil (0.15 to 0.45% w/v) and emulsifier (0.02 to 0.04% w/v). Film thickness and weight increased with increasing buriti oil concentration. The water vapor permeability of the films ranged from 0.22 to 0.366 g mm h−1 m−2 kPa−1. The tensile strength values varied from 4.21 to 6.95 MPa, the elasticity modulus varied from 538.53 to 722.78 MPa, and elongation to rupture varied from 1.13 to 1.66%. The film color was characterized as yellowish, dark, and intense (higher oil content); and clear and a low-intensity color (lower oil content). The films presented a total carotenoid content ranging from 3.63 to 29.73 μg β-carotene/g, which may have resulted in their antioxidant potential against DPPH• (1,1-diphenyl-2-picryl-hydrazyl) radical (from 74.28 to 87.74%). The central formulation of the experimental design (buriti oil 0.30% and emulsifier 0.03%) presented a good performance and can be applied as packaging for foods with a lower water content and that demand protection against oxidation.
Native fruits are economically important to small producers, and they are a important part of the diet of several communities. Therefore, postharvest studies of these fruits are essential. In addition, research involving their chemical composition can identify substances that add potential value to the fruits, especially from a nutritional and medicinal standpoint. This study characterized the fruits of the muricizeiro shrub (Byrsonima crassifolia, Malpighiaceae), which were harvested from native plants on private properties and stored for 16 days at a mean temperature of 12 °C. The fruits were evaluated during storage for: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ascorbic acid content, phenolics and carotenoids total, carotenoids profile, glucose, fructose and sucrose contents. Overall, the temperature that the fruits were storage at was effective at maintaining the quality of the fruit. However, the ascorbic acid content of the fruits did decrease during the storage period. Results showed that the fruits had a high antioxidant capacity, possibly because of the presence of phenolic compounds and carotenoids. It is also important to highlight that this fruit is source of vitamin A, owing to the high concentration of β-carotene.
1 March 2019 in Brazilian Journal of Chemical Engineering
Nanocomposite coatings functionalized with antimicrobial nanoparticles could be a promising alternative for the postharvest preservation of fruits. This study aimed to develop nanocomposite coatings based on pectin incorporated with zinc oxide (NPZ) nanoparticles to preserve the postharvest quality of papaya fruits. The coatings were prepared using pectin (3%) and NPZ (0%–0.4%). The materials were characterized for water-related properties (water solubility and water vapor permeability) as well as physical, mechanical, morphological, rheological, and structural properties. The coatings were applied to papaya fruits, which were analyzed for weight loss, firmness, titratable acidity, and soluble solids over nine days of storage. Incorporating NPZ (0%–0.4%) did not affect the films’ water solubility and vapor permeability. However, films with NPZ exhibited lower mechanical properties than pure pectin films. Rheological behavior testing indicated that the pectin solution was a Newtonian fluid, whereas pectin solutions with zinc nanoparticles were non-Newtonian fluids. The pectin coating with 0.2% NPZ was the most effective in preserving the postharvest quality of papaya by reducing fruit weight loss and acidity content. Therefore, the developed coatings incorporated with NPZ showed promise for the postharvest preservation of papaya fruits.
The objective of this study was to investigate the influence of temperature and pressure on the extraction of Baru almond oil using pressurized CO2. From the obtained data, it was found that variations in pressure and temperature influenced the oil yield and total amount of phytosterols. The maximum yield of Baru oil achieved was approximately 30%, obtained at a pressure of 28 MPa and 60 °C. The phytosterols identified were campesterol, stigmasterol, and β-sitosterol, with a maximum content of 169.5 ± 4.2 mg/100 g of oil obtained at 20 MPa and 60 °C. Among these, β-sitosterol was the most abundant, accounting for 60% of the total phytosterol content under all the experimental conditions. The flavonoid content in the extracts was also quantified, with the total flavonoid levels ranging between 255 and 275 mg/100 g of oil depending on the experimental conditions. The fatty acid profile of the extracted oil predominantly consisted of oleic (51%) and linoleic (28%) acids.