The microstructure and properties of composite gels prepared from konjac glucomannan (KGM) and surface deacetylated chitin nanofibers (S-ChNF) at different concentrations were studied. The results showed that the KGM/S-ChNF composite gel was a pseudoplastic fluid with shear thinning nature, which conformed to the power law model. With increasing S-ChNF concentration, the gel’s viscosity increased, its shear stress decreased, its viscosity coefficient increased from 23.174 Pa·sⁿ to 29.950 Pa·sⁿ, and its flow index decreased from 0.43663 to 0.41308, indicating enhanced pseudoplasticity. Dynamic viscoelastic analysis showed that both the storage and loss moduli were dependent on angular frequency, and displayed an increasing trend with increasing S-ChNF concentration. In addition, the crossing point moved from 6.77 s^-1 to 3.77 s^-1, indicating that the intermolecular hydrogen bonding was enhanced, increasing the resistance to KGM molecular chain movement and prolonging the relaxation time. Consequently, the gel tended to be an elastic fluid. The results of Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and thermogravimetric analysis showed that increasing S-ChNF content could enhance the intermolecular interaction in the composite system, leading to the formation of a stable network structure, thus improving the rheological properties and enhancing the thermal stability of the composite gel.

Curdlan is a microbial extracellular polysaccharide, which has good gel properties, water-holding capacity, thickening capacity and freeze-thaw stability, and is widely used in food industry. Curdlan has been increasingly researched and applied in recent years. In this paper, the sources, chemical structure and functional characteristics of curdlan are reviewed, with emphasis on the latest progress in the application of curdlan in various food processing fields, in order to provide a theoretical reference for further application of curdlan in food processing.

Recently, food grade nanofiber-based materials have received growing attentions in food packaging. In this work, novel active and intelligent packaging nanofibers based on gelatin/ chitosan with curcumin (GA/CS/CUR) were developed via electrospinning technique. Effects of the incorporation of CUR content (0.1%－0.3%, m/m) on the microstructure and functional properties of the electrospun nanofibers were investigated. Morphological studies using scanning electron microscopy indicated that loading CUR can affect the average diameter of nanofiber mats, which remained around 160-180 nm. The addition of an appropriate level CUR (0.2%, m/m) led to a stronger intermolecular interaction, and thus enhanced the thermal stability and tensile strength of the obtained nanofibers. Meanwhile, the incorporation of CUR significantly improved antioxidant activity and the antimicrobial activity of GA/CS/CUR nanofibers. Moreover, the sensitivity of nanofibers to ammonia results indicated that GA/CS nanofibers containing 0.2% CUR (GA/CS/CUR Ⅱ) presented high sensitivity of colorimetric behavior to ammonia (within 3 min). These results suggest GA/CS/CUR Ⅱ nanofibers has great potential as a multifunctional packaging to protect and monitor the freshness of protein-rich animal foods, such as meat and seafood.