RESUMEN

In this study, biodegradable films produced with starch, citric pectin, and functionalized with antioxidant compounds from feijoa (Acca sellowiana (Berg) Burret) were in situ applied for the conservation of ground beef, bread, and grapes. The results demonstrated that the films produced were an excellent source of stable antioxidant compounds, with antimicrobial activity against Escherichia coli, Salmonella, and Shigella. The bioactive films based on biological macromolecules positively stabilized the polyunsaturated fatty acids and deterioration reactions in ground beef. The release of bioactive compounds from the films was responsible for inhibiting molds and yeasts in bread, increasing their shelf life for 30 days of storage. The application of film coating and packaging in grapes increased postharvest conservation and maintained steady physicochemical characteristics. Therefore, the innovative films produced can release bioactive compounds with antioxidant and antimicrobial activity, and consequently, can be proposed as an effective material for food conservation, increasing the shelf life of perishable food products.

Asunto(s)

RESUMEN

BACKGROUND: Feijoa [Acca sellowiana (Berg) Burret] is a Brazilian native fruit with few commercial-level plantations and high agroindustrial potential. A genotype evaluation experiment was conducted from 1996 onward, aiming to obtain fruits based on the agronomical parameters; however, the selection based on chemical composition had not been evaluated with respect to developing a new cultivar. Accordingly, the present study aimed to discriminate seven accessions of feijoa in terms of nutritional composition, phenolic compounds and antioxidant activity using multivariate analysis (principal component analysis and multivariate contrast), targeting the potential production of a new cultivar with better nutritional value and high antioxidant capacity. RESULTS: Feijoa husk presented high content of ashes, lipids, proteins, carbohydrates, phenolic compounds and antioxidant activity compared to feijoa pulp. However, only feijoa pulp was selected to multivariate analysis because it is the fruit edible part. Data variability was explained in 78% and the feijoa pulp accessions were discriminated into four groups related to their characteristics. The accession 5 discrimination can be explained by the high content of ashes, carbohydrates, soluble solids, phenolic compounds and antioxidant activity. Accession 6 was also discriminated by the high content of total acidity, pH and proteins, as well as a low content of soluble solids. CONCLUSION: Feijoa accessions may be indicated for increasing plant selection via hybridization with the other accessions, aiming to produce new cultivars with better nutritional composition and antioxidant capacity. For example, accession 5 is the most suited fruit for human consumption and is a potential plant with respect to becoming a new cultivar. © 2020 Society of Chemical Industry.

Asunto(s)

RESUMEN

Innovative biodegradable packaging with antimicrobial and antioxidant properties was developed, and functionalized with Acca sellowiana waste by-product (feijoa peel flour, FPF). Physicochemical, morphological, antioxidant, antimicrobial properties, and in situ application in the postharvest conservation of apple were conducted with the packaging produced. The results obtained demonstrate that FPF addition had a positive influence on the packaging characteristics, for all the parameters tested. The high concentration of antioxidant compounds in the films with FPF promoted antimicrobial activity against Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa. The packaging produced maintained the quality of apples during storage, with constant weight after 5 days of storage. Based on our results, the bioactive, antioxidant and antimicrobial packaging functionalized with Acca sellowiana waste by-product may be considered as a new alternative to packaging in food systems.

Asunto(s)

RESUMEN

BACKGROUND: The international marketing of native Brazilian fruits may benefit from research into discrimination between plants with particular properties. Plants with certain characteristics have strong potential for use in agroindustry and for the development of new processed products. In the current study, 12 uvaia plants (Eugenia pyriformis Cambess), native to Brazil, were geographically discriminated by chemometric methods, using nutritional composition, physicochemical characterization, bioactive compounds, and antioxidant capacity data. RESULTS: Uvaia fruits presented good nutritional value, with a high moisture and carbohydrate content. All fruits presented a pH value lower than 4, being classified as highly acidic, and the total soluble solids (°Brix) ranged between 2.90 and 9.80. Some plants had a higher vitamin C content, and all the plants had a high bioactive compound content (phenolic and flavonoids) and antioxidant capacity in 1,1-difenil-2-picrilhidrazil (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Hydroethanolic solution was the best extraction solvent tested when compared with water and ethanol. Using principal component analysis, it was possible to discriminate among the plants in five different groups; however, just one group was responsible for higher antioxidant compound content. CONCLUSION: In this work, 12 native uvaia plants were discriminated by their geographical origin using a chemometric approach. Genetic improvement based on natural selection could be accomplished with some of the plants to improve the quality of uvaia pulp and to develop new cultivars. © 2019 Society of Chemical Industry.

Asunto(s)

RESUMEN

Methylcellulose is a biopolymer, which can be used in the preparation of films for the production of biodegradable active packaging. In this work, the methylcellulose films containing biosynthesized silver nanoparticles (AgNPs) were developed using Lippia alba extract. The physico-chemical, antioxidant, and antimicrobial properties of the films were studied. The insertion of Lippia alba compounds was verified using infrared spectroscopy (FTIR), with the appearance of a band at 1595 cm-1 and 1410 cm-1 which is characteristic of CCC stretches of the aromatic ring, and the increase in the hydrophobicity of the films containing the extract in relation to the control film. The films containing AgNPs presented a decrease in tensile strength and elastic modulus, but increased elongation. It was observed that the films that contain AgNPs presented superior antioxidant activity compared to the other films, besides antimicrobial activity against the tested microorganisms.

Asunto(s)

RESUMEN

This study evaluated whether the essential oil of Lippia alba (EO) used as a sedative for fish transport would increase the stability of silver catfish during ice storage. Fish were transported (6 h) with water alone (control), 30 or 40 µL/L of EO in water. After transport, fish were slaughtered and stored in ice. Data on mesophilic and psychrotrophic bacteria counts during storage did not support the evidence for the antimicrobial activity of EO. However, fish treated with EO (30 and 40 µL/L) had delayed onset of rigor mortis, delayed increase of pH after 34 days of storage, and delayed peak of hypoxanthine formation and its degradation. In addition, the demerit sensory score of EO-treated fish (30 and 40 µL/L) was lower than that of controls along the storage. Thus, the use of EO as a sedative in the water used to transport silver catfish can delay the loss of freshness and the deterioration of whole fish stored in ice.