Optimization and Characterization of Shrimp Flavor Nanocapsules Containing 2,5-Dimethylpyrazine Using an Inclusion Approach.

The major flavor component of shrimp and prawn, 2,5-dimethylpyrazine, was embedded into hydroxypropyl-β-cyclodextrin (HP-β-CD) to form nanocapsules using an inclusion method. Response surface methodology was used to optimize the processing variables. The inclusion was characterized, and its behavior and the interactions between 2,5-dimethylpyrazine and HP-β-CD were determined through dynamic light scattering, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR) and thermal gravity analysis (TGA). The optimum inclusion conditions are as follows: a 2.25:1 ratio of external to internal capsule, a 2.39% solid content and a 4.48:1 ratio of emulsifier to flavor. Formation of the inclusion complex composed of 2,5-dimethylpyrazine and HP-β-CD was demonstrated using SEM and TEM. FT-IR spectroscopy showed that 2,5-dimethylpyrazine was encapsulated into the HP-β-CD nanocapsules. TGA illustrated that the flavor-loading ratio of the nanocapsules reached 27.76%. These data demonstrate that the flavor nanocapsules exhibit good potential for 2,5-dimethylpyrazine application in food industries. Practical Applications Shrimp and crab are very popular seafoods in China and many other countries. However, 2,5-dimethylpyrazine, the major flavor component in seafoods, is unstable in normal condition. Therefore, the preservation of 2,5-dimethylpyrazine is necessary for its application in food industries. In this study, 2,5-dimethylpyrazine was successfully embedded into hydroxypropyl-β-cyclodextrin. The response surface methodology was employed to optimize the effects of the processing variables. And the nanocapsules expressed good characters. [ABSTRACT FROM AUTHOR]