RESUMO
Three red color fruit juice (pomegranate (PJ), barberry (BJ), and grape juice (GJ)) and three plant extracts (cardamom essential oil (CE), ginger extract (GE), and hibiscus solution (HS)) were used for the development of different functional beverages. Organoleptic analysis was done to detect the most acceptable fruit juice blend. The physicochemical properties of the samples including total phenols, 1,1-diphenyl-2-picrylhydrazyl (DPPH) inhibition percent, anthocyanin, flavonoid, and vitamin C content of optimum fruit juice blend (60% PJ/20% BJ/20% GJ) were 121.57 µg gallic acid equivalent (GAE)/ml, 80.28%, 4.03 mg/L, 64.87 mg/100 ml, and 51.10 mg/100 ml, respectively. To determine the optimum level of extracts and essential oil (GE, CE, and HS) in fruit juice blends, the mixture design method was used and 14 runs (formulations) were obtained. In all formulations, samples containing HS had the highest content of antioxidant and active components and the statistical analysis indicated that the sample containing 0.5 CE/0.5 GE/1 HS (ml/100 ml) had the optimum content of antioxidant components. Thus, the results of this study introduce a functional drink possessing high polyphenols, antioxidants, anthocyanin, and vitamin C content.
RESUMO
This research extends the effect of packaging with bovine gelatin, gelatin nanocomposite (GN), gelatin emulsion (GE), two layers gelatin nanocomposite and gelatin emulsion (GNE), and polyethylene (PE) films on sponge cake properties during storage at 25°C and 55 ± 2% RH. In this regard, water vapor permeability (WVP) and oxygen permeability (OP) of films were compared. Then, moisture content, acidity, peroxide value, texture profile, organoleptic properties, and fungal growth of packed cakes were determined. Results showed that the addition of nanoparticles could reduce the water vapor permeability from 9.680 ± 0.460 × 10-10 (g m/sm-2Pa-1) for net gelatin film to 6.067 ± 0.337 × 10-10 (g m/sm-2 Pa-1) for gelatin nanocomposite film and oxygen permeability from 39.262 (cm3µm/ m2dkPa) for net gelatin film to 29.645 (cm3µm m-2 dkPa) for nanocomposite film. However, GNE films had the highest barrier properties. Results of acidity and peroxide values of cakes admitted the sufficiency of GNE films for sponge cakes packaging. In addition, antifungal properties of nanoparticles led to less fungal growth on cakes packed in GNE films. The cakes packed in GNE films own more organoleptic and texture acceptability than the ones packed in other films. Generally, according to the results GNE films are acceptable for packaging of sponge cakes which contain no preservative because this packaging can prevent fungal growth for a longer time and even more can maintain the cake chemical and organoleptic quality.
RESUMO
The gelatin-based nanocomposite films containing chitin nanoparticles (N-chitin) with concentrations of 0, 3, 5 and 10% were prepared and their physical, thermal and anti-microbial properties were investigated. Scanning electron microscopy (SEM) micrographs showed that N-chitin size distribution was around 60-70nm which dispersed appropriately at low concentration in gelatin matrix. The results showed that incorporation of N-chitin significantly influenced apparent color and transparency of the gelatin films. The reduced water vapor permeability (WVP) and solubility and higher surface hydrophobicity of the nanocomposite films were obtained by enhancing N-chitin concentration in film formulation. The use of N-chitin up to 5% concentration in the gelatin based nanocomposite film led to improved mechanical properties. Also, the results of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) confirmed improved stability of nanocomposite films against melting and degradation at high temperatures in comparison to neat gelatin film. The well compatibility of chitin nanoparticles with gelatin polymer was concluded from Fourier transform infrared (FTIR) spectra and X-ray diffraction (XRD) plots. Finally, the gelatin based nanocomposite films had anti-fungal properties against Aspergillus niger in the contact surface zone. Increasing the concentration of N-chitin up to 5% enlarged inhibition zone diameter, but the nanocomposite film containing 10% N-chitin showed smaller inhibition zone.
