Effect of Adding Red Propolis to Edible Biodegradable Protein Films for Coating Grapes: Shelf Life and Sensory Analysis.

Red propolis is an active ingredient of great nutritional interest which offers numerous benefits as an antioxidant and antimicrobial agent. Thus, the objective of this research was to evaluate the application of an edible and antimicrobial gelatine coating containing red propolis to increase the shelf life of grapes. Gelatine films with an addition of 5, 10, 15, 20 and 25% of red propolis extract were produced to evaluate their antimicrobial activity using the disk diffusion test in solid media. The films with 25% red propolis extract showed antimicrobial activity against the bacteria Staphylococcus aureus and Pseudomonas aeruginosa. The grapes were coated with pure gelatine, without a plasticizer and with gelatine with 25% red propolis and then stored for 1, 4, 10, 19 and 25 days at temperatures of 25 °C and 5 °C. The results showed that the gelatine coating with propolis reduced the mass loss of grapes stored at 25 °C for 19 days by 7.82% and by 21.20% for those kept at 5 °C for 25 days. The pH, total titratable acidity, soluble solids and color of the grapes increased due to the ripening process. Furthermore, the sensory acceptability indexes of the refrigerated grapes with coatings were superior (>78%) to those of the control samples (38%), proving the effectiveness of the coatings in maintaining the quality of grapes during storage.

Multipurpose arrowroot starch films with anthocyanin-rich grape pomace extract: Color migration for food simulants and monitoring the freshness of fish meat.

Extraction of anthocyanins from grape pomace, is a way of valuing these abundant by-products with low added value. Its integration into films may allow it to be used in bioactive packaging, which creates new color and solubility properties for food and smart food packaging which tracks the freshness of fish. Films of arrowroot starch added with different concentrations of grape pomace extract (GPE) were flexible to handle, reddish and presented a high content of anthocyanins. The water vapor permeability increased by 17 %, while the tensile strength of arrowroot starch film decreased by 79 % with the addition of 40 % GPE. The addition of GPE increased the solubility of the starch film in aqueous and lipid food simulants by 121 and 119 %. The GPE pigment preferentially migrated to the aqueous simulant due to the hydrophilic nature of anthocyanins and starch. The GPE film showed distinguishable color changes in different pH buffer solutions from pink at pH 2 to light blue at pH 7 and slightly yellowish green at pH 10. When the composite films were monitored for fish meat freshness, the change in color of the film from reddish pink to slightly green after 96 h of storage at 25 °C was evident.

Effect of the addition of Euterpe oleracea Mart. extract on the properties of starch-based sachets and the impact on the shelf-life of olive oil.

This study aimed to produce and characterized active biodegradable packages by extrusion of cassava starch, biodegradable polyester, plasticizer, and acai extract (EA 0, 1, 2, 3 and 4%) and to evaluate its effects on extra virgin olive oil (EVOO) for 120 days. All analyses were performed at the beginning (day 0) and the end of the experiment (day 120). The oil was characterized for acidity index (IA), peroxide index (IP), thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD), phenolic compounds (PC) and color parameters. The incorporation of EA at the initial time caused increased thickness, mechanical properties, solubility in water and oil in all formulations. The some values of properties increased or decreased, due to the interaction of the stored product and packaging. At the end of the storage period, the values of IA and IP were below the limits established by current legislation. The EVOO showed a gradual decrease in PC from day 1 to day 120, for all treatments.

Bioactive Films Based on Starch from White, Red, and Black Rice to Food Application.

Packages from renewable sources have been the focus of many studies, due to the consumer needs for high-quality food, environmental concern related to the inadequate discard of packaging, low percentage of packaging recycling, and starch application by a viable method. Thus, this work aimed to develop bioactive packages based on white, red, and black rice starch and analyze the influence of macromolecule and plasticizer type, even its blends, on the characteristics of films. Films were characterized by color, opacity, thickness, water solubility, water vapor permeability, and bioactive properties. The use of rice starch in the development of edible and/or biodegradable films was feasible, with all the formulations tested presenting a homogeneous matrix and the films obtained varying in hue, to the naked eye, as a function of the starch used. Variation of the type of starch and plasticizer, as well as the concentrations of the same, resulted in films with differences in all studied properties. Films prepared with 5% of starch and 30% of sorbitol showed phenolic compounds and antioxidant capacity, using the DPPH and ABTS methods, indicating that these can be considered bioactive packages and also suitable for food application.

Production of Edible Films Based on Pea Starch with Incorporation of Active Compounds Obtained from the Purple Araçá (Psidium myrtoides).

The aim of this study was to incorporate the active compounds present in purple araçá (Psidium myrtoides) in pea starch-based films and to verify the influence of different plasticizers (glycerol, sorbitol, and polyethylene glycol 400) on film properties. Films were produced and characterized in relation to visual appearance, active compounds, antimicrobial activity, and mechanical and barrier properties. Pea starch has a high amylose content and a final viscosity of 5371.5 RVU, which contributes to the elaboration of films even without the addition of plasticizers. Purple araçá and pea starch formed films with good water vapor barrier characteristics (0.398 g·mm/m2·h·KPa) and low solubility (33.30%). Among plasticizers, sorbitol promoted a lower permeability to water vapor. The selected formulations, 0%, 20%, and 30% sorbitol, presented a high concentration of phenolic compounds (1194.55, 1115.47, and 1042.10 mg GAE 100 g-1, respectively) and were able to inhibit the growth of Staphylococcus aureus. Therefore, films contained the active compounds of purple araçá and potential to be used as food packaging.

Antimicrobial Activity and GC-MS Profile of Copaiba Oil for Incorporation into Xanthosoma mafaffa Schott Starch-Based Films.

The present study evaluated the effect of the incorporation of copaiba oil, in direct and in microencapsulated form, into films based on Xanthosoma mafaffa Schott starch. Initially, the characterization of copaiba oil by gas chromatograph coupled with mass spectrometry (GC-MS) and its antimicrobial activity against gram-positive and gram-negative bacteria was performed. The films were produced by the casting technique and characterized in relation to physical, chemical, structural, and antimicrobial activity. Sesquiterpenes, mainly ß-caryophyllene, were the predominant compounds in copaiba oil, showing antimicrobial activity against B. subtilis and S. aureus. The films showed forming capacity, however, was observed a decrease in solubility and revealed an increase in hydrophobic characteristics. However, the oil reduced the tensile strength and elongation, while the microcapsules did not influence the mechanical properties in comparison to the control film. From microstructure analysis, changes in the films roughness and surface were observed after the addition of oil both directly and in microencapsulated form. Films incorporated with microparticles were able to inhibit the gram-positive bacteria tested, forming inhibition zones, indicating that the encapsulation of copaiba oil was more efficient for protecting bioactive compounds from the oil, suggesting the possible application of mangarito starch-based films incorporated with copaiba oil as biodegradable packaging.

Methods of Incorporating Plant-Derived Bioactive Compounds into Films Made with Agro-Based Polymers for Application as Food Packaging: A Brief Review.

Plastic, usually derived from non-renewable sources, is among the most used materials in food packaging. Despite its barrier properties, plastic packaging has a recycling rate below the ideal and its accumulation in the environment leads to environmental issues. One of the solutions approached to minimize this impact is the development of food packaging materials made from polymers from renewable sources that, in addition to being biodegradable, can also be edible. Different biopolymers from agricultural renewable sources such as gelatin, whey protein, starch, chitosan, alginate and pectin, among other, have been analyzed for the development of biodegradable films. Moreover, these films can serve as vehicles for transporting bioactive compounds, extending their applicability as bioactive, edible, compostable and biodegradable films. Biopolymer films incorporated with plant-derived bioactive compounds have become an interesting area of research. The interaction between environment-friendly biopolymers and bioactive compounds improves functionality. In addition to interfering with thermal, mechanical and barrier properties of films, depending on the properties of the bioactive compounds, new characteristics are attributed to films, such as antimicrobial and antioxidant properties, color and innovative flavors. This review compiles information on agro-based biopolymers and plant-derived bioactive compounds used in the production of bioactive films. Particular emphasis has been given to the methods used for incorporating bioactive compounds from plant-derived into films and their influence on the functional properties of biopolymer films. Some limitations to be overcome for future advances are also briefly summarized. This review will benefit future prospects for exploring innovative methods of incorporating plant-derived bioactive compounds into films made from agricultural polymers.

Extraction and characterization of starches from pigmented rice.

The aim of this work was to extract and characterize starch from three varieties of pigmented rice (named white, red and black), preserving the bioactive compounds. The extraction yield was 44.0%, 47.0% and 35.7%, respectively. The scanning electron microscopy showed that the granules of the three varieties presented polygonal and angular format and absence of impurities. The chemical analyzes, showed more than 83.0% of carbohydrates in the three compositions. There was retention of the phenolic compounds from the raw material in the starches. With regard to pasting properties of the starches, differences were observed in initial temperature, which was of 80.6 °C, 79.1 °C and 88.8 °C for the starches of white, red and black rice, respectively. Black rice starch also showed slightly higher crystallinity and thermal stability than white and red rice starches. Gels of red rice starch have higher syneresis in five freeze-thaw cycles, when compared to the others.

Influence of spray drying on bioactive compounds of blackberry pulp microencapsulated with arrowroot starch and gum arabic mixture.

The objective of this research work was to obtain blackberry pulp in microencapsulated powder with a of arrowroot starch/gum arabic mixture by spray drying. Experimental design, with 11 runs, was performed to evaluate the effects of inlet air temperature (100-150 °C) and encapsulating agent concentration (1:0.5-1:2, blackberry pulp solids: arrowroot starch/gum arabic) on the functional properties of powders. The ascorbic acid content and luminosity of the powder increased with increasing encapsulating agent concentrations, whereas the b* values decreased. Increasing the inlet air temperature and decreasing the encapsulating agent concentration, the content of anthocyanins also increased. The powders were able to reduce Fe+3 and to trap free radicals, showing antioxidant property. The temperature of 143 °C and concentration of encapsulating agent 1:1.78 were the ideal conditions to have high content of ascorbic acid and good content of anthocyanins and antioxidant properties.

Active Edible Films Based on Arrowroot Starch with Microparticles of Blackberry Pulp Obtained by Freeze-Drying for Food Packaging.

This research work evaluated the influence of the type of incorporation and variation in the concentration of blackberry pulp (BL) and microencapsulated blackberry pulp (ML) powders by freeze-drying on the chemical and physical properties of arrowroot starch films. Blackberry powders were added to the film-forming suspension in different concentrations, 0%, 20%, 30% and 40% (mass/mass of dry starch) and through two different techniques, directly (D) and by sprinkling (S). Scanning electron microscopy (SEM) images revealed that the incorporation of blackberry powder has rendered the surface of the film rough and irregular. Films incorporated with BL and ML powders showed an increase in thickness and water solubility and a decrease in tensile strength in comparison with the film containing 0% powder. The incorporation of blackberry BL and ML powders into films transferred colour, anthocyanins and antioxidant capacity to the resulting films. Films added with blackberry powder by sprinkling were more soluble in water and presented higher antioxidant capacity than films incorporated directly, suggesting great potential as a vehicle for releasing bioactive compounds into food.

Bioactive films of arrowroot starch and blackberry pulp: Physical, mechanical and barrier properties and stability to pH and sterilization.

The influence of the incorporation of blackberry pulp on properties of arrowroot starch films has been studied. The blackberry pulp transferred bioactive compounds, antioxidant capacity and color to arrowroot starch films. Increasing the concentration of blackberry pulp (from 0 to 40%, mass/mass of dry starch) in the film resulted in increased thickness (from 0.065 to 0.133 mm), increased elongation (from 3.18 to 13.59%), decreased tensile strength (from 22.71 to 3.97 MPa), increased water vapor permeability (from 3.62 to 4.60 g.mm/m2.day.kPa) and solubility in water (from 14.18 to 25.46%). The films were stable to different media, maintaining the same initial diameter dimensions after immersion in acidic, neutral and alkaline solutions, but their color intensity was reduced, probably due to the release of anthocyanins to the solutions. The films with blackberry pulp presented darkness after sterilization process.

Characterization and optimization of oil microcapsules from Attalea phalerata Mart. for the preservation of bioactive compounds

This study aimed microencapsulating Attalea phalerata Mart. oil, containing high carotenoid and phenolic compounds content, with Arabic gum and gelatin, using the complex coacervation method. The yield, efficiency, morphology of microcapsules and content of phenolic compounds, carotenoids and antioxidant activity in different processes conditions (concentration of the filling, temperature and agitation speed) were evaluated. The results showed 88% of yield, efficiency up to 70% and a characteristic size of microcapsules. The amount of carotenoids was high in crude oil (394.84 µg of carotenoids/g oil) and the microencapsulation tests showed amounts of 19.19 to 166.40 µg of carotenoids/g oil. The phenolic compounds in the crude oil were 20.73 mg GAE/g sample and the microencapsulation tests showed amounts of 3.17 to 15.16 mg GAE/g oil. The values of bioactive compounds influenced in the antioxidant activity though ABTS•+ method with values of 161.70 µM trolox/g oil to crude oil and 7.70 and 159.54 µM trolox/g oil for microcapsules tests.

Extraction and characterization of arrowroot (Maranta arundinaceae L.) starch and its application in edible films.

This research work aimed extraction and characterization of arrowroot starch. Besides, the effects of different concentrations of starch (2.59-5.41%, mass/mass) and concentrations of glycerol (9.95-24.08%, mass versus starch mass) on films properties were evaluated by a rotational central composite 22 experimental design. Arrowroot starch showed high amylose content (35%). Low values were found for the swelling power and solubility index. The X-ray diffraction showed "C" type crystalline structures, while thermogram showed Tg around of 118 and 120 °C. The thermogravimetric analysis showed that 40% of mass loss of starch occurred between 330 and 410 °C. The films were homogeneous, transparent and manageable. Starch and glycerol concentrations played a significant role in thickness and solubility in water of films, but was not significant for water vapor permeability and tensile strength. Therefore, arrowroot is a very promising starch source for application in films.