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This study aimed to produce a whey protein isolate (WPI) based nanocomposite film containing copper oxide nanoparticles (CuONPs) with coconut essential oil (CEO) (0, 0.4, 0.8% w/v) and paprika extract (PE) (0, 0.03, 0.06% w/v) using a central compound design (CCD). Antioxidant capacity, water vapor permeability, mechanical properties, antimicrobial activity, morphological characteristics Fourier transform infrared (FTIR), X-ray diffraction (XRD), and thermal properties of films were investigated. In addition to the properties of CuONPs, CEO, and PE, this effect was due to hydrogen interactions between them and the biopolymer matrix. As confirmed by the FTIR and XRD, the co-application of PE and CEO due to the synergistic effect of pigment on the antimicrobial properties of CEO and increasing the content of antimicrobial compounds in the film showed the highest activity against Staphylococcus aureus and Escherichia coli. The results of the thermal property analysis of the films showed the formation of a complex between the nanocomposite film with CEO and PE. In summary, the results of the present study showed that nanocomposite films containing the combination of PE and the CEO could be useful in food packaging. [ABSTRACT FROM AUTHOR]

Considering the significance of natural antioxidants to preserve meat, the present study was undertaken to evaluate the efficacy of a deflavored and decolorised extract of rosemary (StabilRose™) for the production and preservation of naturally colored fresh meat. Oxidative rancidity of meat and color degradation of paprika oleoresin were exploited as model systems and compared with butylated hydroxyanisole (BHA). The results showed similar efficacy for 3% carnosic acid extract and BHA, with further enhancement in efficacy with respect to the carnosic acid content. A synergetic antioxidant effect of carnosol on carnosic acid content was also noticed to an extent of 1:1 (w/w) ratio, and further increase in carnosol content showed no improvement in the antioxidant efficacy. Finally, stabilized paprika and optimized rosemary extract containing carnosic acid and carnosol in 1:1 (w/w) ratio was successfully applied to produce naturally colored meat suitable for storage at 4 ± 1 °C. [ABSTRACT FROM AUTHOR]

The natural pigments in paprika were rapidly and efficiently separated by ultra high performance supercritical fluid chromatography. The separation of both un-saponified and saponified mixtures of paprika oleoresin were optimized, with run times of 10.6 min. Three different C18 columns, a cyano, silica and diol column, all 3 × 100 mm, with 1.8 μm particles were compared. The best separation for the un-saponified sample was found with an SB-C18 column, while the saponified samples were best separated on a bare silica, RX-Sil column. A SB-CN column allowed near optimum separation of both the unsaponified, and saponified samples, with similar run times. The best mobile phase was carbon dioxide (CO) modified with isopropyl alcohol (IPA), with a composition gradient. Fingerprints of several commercial pepper products indicated that one appeared to be colored with artificial dyes, while the color of a chili powder may have been enhanced with a paprika extract. Spectra, using CO with IPA as modifier, produced a single maximum at 453 nm, which appears to represent up to a 30 nm solvatochromic shift from the maxima in most organic solvents. Acetonitrile (ACN) as modifier produced spectra with two maxima and a similar solvatochromic shift. These results appear to be the first on saponified paprika oleoresin samples using SFC. It is also the first detailed report on the separation of un-saponified samples. The results are up to six times faster than comparable results by HPLC. It appears that SFC is a viable, superior alternative to HPLC for the analysis of this important commercial product, without using ACN, or chlorinated solvents. [ABSTRACT FROM AUTHOR]

A method for the determination of tocopherols and tocopherol esters, quantified as tocopherol acetate, in paprika and paprika oleoresin is reported. Paprika samples were extracted with ethyl acetate and aliquots of the extracts were directly injected into a liquid chromatograph. Reverse phase high-performance liquid chromatography with spectrophotometric detection at 280 nm was used. Gradient elution was applied, allowing the determination of tocopherols and tocopherol esters in the presence of carotenoids. The method does not need previous separation steps, so is useful for the routine determination of vitamin E in commercial samples. [ABSTRACT FROM AUTHOR]