Microencapsulation of L-Lysine for Improving the Balance of Amino Acids in Ruminants

ved October 28, 19.9.9 and aaepted Novenwer 5, 1999) L-Lysine was microencapsulated by the spray-dry met.hod for improvement of the balance of alllino acids in ruminants. The rumen-bypm;s lllicrocCljJsulc was jJrqmn~d using zein or shellac as an outer coat.ing agcnt [or protection against microbial degradation in the rumen. L-Lysine was generated with a .yield of ,')0% in casp of zein microcapsules and :3:3% in shellac microcapsules and a mean particle di,uneter of 20-30 pItt. Bot.h rumen b:ypass microcapsules had high stability in a neutral solution that mimicked ruminal pH (pI-I 6.f:i), suggesting t.hat L-l:ysinc should not be susceptible lo damage by rLiminal microorganisms. Moreover, tilt' efficiency of release of these microcapsules was 70% in the zein microcapsule and 85% in the shellac microcapsule within only 30 min in the abomasal environment (pH :U)) In addition, about 90% of encapsulated L-lysine \'las released from zein microcapsules in pepsin solution.