Microencapsulation of L-lysine for improving the balance of amino acids in ruminants

Abstract

L-Lysine was microencapsulated by the spray-dry method for improvement of the balance of amino acids in ruminants. The rumen-bypass microcapsule was prepared using zein or shellac as an outer coating agent for protection against microbial degradation in the rumen. L-Lysine was generated with a yield of 50% in case of zein microcapsules and 33% in shellac microcapsules and a mean particle diameter of 20-30 μm. Both rumen-bypass microcapsules had high stability in a neutral solution that mimicked ruminal pH (pH 6.5), suggesting that L-lysine should not be susceptible to damage by ruminal microorganisms. Moreover, the efficiency of release of these microcapsules was 70% in the zein microcapsule and 85% in the shellac rnicrocapsule within only 30 min in the abomasal environment (pH 3.0). In addition, about 90% of encapsulated L-lysine was released from zein microcapsules in pepsin solution.