Structure and physicochemical properties of rice starch modified with dodecenyl succinic anhydride and its use for microencapsulating Pediococcus acidilactici probiotic.

Polysaccharides are used as wall materials to extend the shelf life of lactic acid bacteria. Ice crystal formation during freezing leads to probiotic death. We prepared a series of dodecenyl succinic anhydride (DDSA)-modified rice starches with varying degrees of substitution and compared their functional properties. Fourier-transform infrared spectroscopy, X-ray diffraction analysis, and nuclear magnetic resonance results confirmed successful DDSA modification and the disruption of the long-range ordering of starch molecules. The structural changes modified the physicochemical properties of starch. For example, the apparent viscosity and viscoelastic characteristics of modified rice starch increased, and its freeze-thaw stability and emulsion capacity were remarkably improved after DDSA modification. Moreover, the modified starches exhibited promising performance for microencapsulating Pediococcus acidilactici. This study describes a rice starch derivative with excellent physicochemical properties that can be used to enhance the storage stability of bioactive probiotics.