The Collaborative International Dictionary of English v.0.48:

Emulsin \E*mul"sin\, n. [See Emulsion, Emulge.] (Chem.)
   (a) The white milky pulp or extract of bitter almonds. [R.]
   (b) An unorganized ferment (contained in this extract and in
       other vegetable juices), which effects the decomposition
       of certain glucosides.
       [1913 Webster]