Sequential extraction of anthocyanins and pectin from jabuticaba (Plinia cauliflora) peel: Peel pretreatment effect and ultrasound-assisted extraction.

The jabuticaba bark is rich in anthocyanins and fibers, and its use may be of industrial interest. In the food sector, its used as an ingredient in the production of fermented products, liqueurs or enriched flours. It also has pharmaceutical and cosmetic applications. The objective was to evaluate the effect of pretreatment and fresh use of jabuticaba peels in the extraction of total phenolic compound (TPC) and total anthocyanin (TA) contents with and without ultrasound assistance and in the sequential extraction of pectin from the residue. In the TPC and TA extraction, a 3x2 factorial design was used. For conventional anthocyanin extraction (CAE), occurred in an incubator under agitation. For ultrasound-assisted anthocyanin extraction (UAE) was utilized an ultrasonic homogenizer with probe (20 kHz, 160 W). The extracts were quantified (TPC, TA, antioxidant activity and color). The residues were characterized and used for sequential pectin extraction, which was quantified and characterized. The results were subjected to analysis of variance. Fresh jabuticaba peel is a residue that can be used to sequentially extract phenolic compounds, particularly anthocyanins and pectin. The use of ultrasound (UAE) was less efficient than CAE for extracting TPC and TA or performing sequential extraction on all pretreatment peels.

Rheological parameters of mixed Brazilian Cerrado fruits sugar-free preserves: the effect of body agents.

The aim of this study was to evaluate the effect of the bodying agents (erythritol, sorbitol, xylitol, and polydextrose) and their mixtures on the preparation of mixed Brazilian Cerrado fruit preserves (marolo, soursop, and sweet passion fruit). Mixture design was used for product optimization and the preserves were evaluated by texture profile, stress relaxation test, and uniaxial compression test. The research data were analyzed using regression equations on SAS software. The results indicated that the rheological parameters were affected by the body agents. Erythritol should not be used as an isolated component because it provoked changes in the properties of the final product (harder and brittle preserves); xylitol and sorbitol made preserves more elastic, cohesive, and more fragile; and polydextrose showed a synergistic effect with erythritol for rupture deformation and lesser effects for hardness, adhesiveness, and gumminess.

Mechanical and structural characterization of whey protein concentrate/montmorillonite/lycopene films.

BACKGROUND: The production/characterization of nanocomposites based on whey protein concentrate (WPC) and montmorillonite (MMT) with lycopene as functional substance is presented and their potential use as alternative biomaterials in foodstuff applications is discussed. A full factorial design with varying levels of MMT (0 and 20 g kg-1 ) and lycopene (0, 60 and 120 g kg-1 ) was used. The mechanical properties (tensile and puncture tests), thermal stability, Fourier transform infrared vibrational spectra and film morphology of the resulting materials were evaluated. RESULTS: Lycopene and MMT nanoparticles could be successfully included in WPC films using the casting/evaporation method. The films were flexible and homogeneous and a uniform dispersion of the components was achieved. CONCLUSION: Inclusion of 20 g kg-1 of MMT in the polymeric matrix improved both mechanical and thermal properties. Lycopene at the tested concentrations, besides its red coloring ability, did not promote any detectable interference in the structural or physical properties. These findings are important in devising applications and open a new perspective on the use of these materials in bioactive packaging processing. © 2017 Society of Chemical Industry.

Use of allyl isothiocyanate and carbon nanotubes in an antimicrobial film to package shredded, cooked chicken meat.

We developed antimicrobial packaging incorporated with allyl isothiocyanate (AIT) and carbon nanotube (CNT), and this packaging was used for shredded cooked chicken meat inoculated with Salmonella Choleraesuis. The following parameters were analysed during the 40 days of storage: microbial counts, colour characteristics and changes in the oxidation of the meat as well as changes in the mechanical properties of the film, the structure of the antimicrobial film and the diffusion of the antimicrobial agent into the food. The incorporation of AIT into the films increased the elongation at the break (E) value of the films and decreased the tensile strength (TS) value of the films. The CNT was important to retain the AIT which is a volatile substance in the film. The diffusion of the AIT from the film into the chicken reduced the microbial contamination, controlled oxidation and reduced the colour changes. Thus, these packages were effective for the 40 days of storage.