Application of xanthan gum and konjac gum to improve the texture, rheological properties and microstructure of Oviductus Ranae gel.

The effects of xanthan gum (XG), konjac gum (KG) and mixed gum of XG and KG (MG) on the gel properties of Oviductus Ranae (OR) were studied using texture analysis, dynamic rheometry, scanning electron microscopy and Fourier transform infrared spectroscopy. The addition of both XG and MG can increase the hardness and water-holding capacity and energy storage modulus of the OR gel, but the addition of KG has the opposite effect. When the mass ratio of XG to KG is 1:1, the hardness (730 g), springiness (1.00) and chewiness (218.48 g) of the OR gel are all maximized. The addition of MG significantly more enhances the hydrogen bond and hydrophobic interaction, compared with the addition of only XG or KG, so the OR gel forms a denser and more stable network structure. Our results provide valuable information for further design and preparation of OR gel foods containing XG and KG.

Preparation and Characterization of Ginger Essential Oil Microcapsule Composite Films.

New food packaging has shown research significance in the face of increasing demand for high-quality foods and growing attention paid to food safety. In this study, ginger essential oil microcapsule composite films were prepared by combining microcapsules prepared by a complex coacervation method with gelatin films, and the mechanical properties and active functions of the composite films were analyzed. Fourier-transform infrared spectroscopy and differential scanning calorimetry confirmed the successful encapsulation of ginger essential oil. The scanning electron microscopy of the composite films showed the microcapsules and gelatin film matrix were highly compatible. During the entire storage period, the antioxidant capacity of the ginger essential oil microcapsule films weakened more slowly than ginger essential oil microcapsules and could be maintained at a relatively high level for a long time. The microcapsule films had excellent inhibitory effects on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. Therefore, the direct addition of microcapsules to a film matrix can broaden the application range of microcapsules and increase the duration of the release of active ingredients. Ginger essential oil microcapsule films are potential biodegradable food packaging films with long-lasting activity.

Effects of ultrasonic pretreatment on the structure and functionality of chicken bone protein prepared by enzymatic method.

This study investigated the application of ultrasonic pretreatment (UP) to assist with enzymatic extraction of chicken bone protein. Relevant parameters of UP including ultrasonic power, duration of treatment and temperature were studied. The effect of ultrasound was evaluated by examining the protein structure changes (i.e. surface hydrophobicity, secondary and tertiary structures, molecular weight distribution) and their functionalities (i.e. solubility, oil holding capacity, foaming and emulsifying properties). Higher protein extraction yield and surface hydrophobicity were evident after UP, along with the changes in the secondary and tertiary structure of the protein. UP alone effects the proteins having molecule weight at about 100 kDa. Results also reveal UP was capable of enhancing the protein functionalities. Therefore, UP could be applied as a suitable technology to improve the yield and quality of the protein extracted from chicken bone by enzymatic method, and as such, facilitating the potential utilization of waste byproduct from poultry industry.