NOVELTY - Producing alkyl R-lactate comprises (a) producing an intermediate comprising R,R- and S,S-lactide from an initial compound comprising propanal units (I), where the initial compound is subjected to stereoisomerization conditions, and (b) reacting at least a portion of the intermediate with an alkyl alcohol to produce a product comprising alkyl R-lactate, where alkyl R-lactate is produced in the presence of an enzyme.    USE - The processes are useful for producing alkyl R-lactate, R-lactic acid, oligomeric R-lactic acid, R,R-lactide, poly-R-lactic acid, stereocomplex lactic acid and alkyl S,S-lactyl lactate (all claimed), where the lactic acid is useful: for chemical and pharmaceutical industries.    ADVANTAGE - The process economically produces alkyl R-lactate with improved biodegradability, polymer crystallinity, flexibility and solubility and high enantiomeric purity.    DETAILED DESCRIPTION - Producing alkyl R-lactate comprises (a) producing an intermediate comprising R,R- and S,S-lactide from an initial compound comprising propanal units of formula (I), where the initial compound is subjected to stereoisomerization conditions, and (b) reacting at least a portion of the intermediate with an alkyl alcohol to produce a product comprising alkyl R-lactate, where alkyl R-lactate is produced in the presence of an enzyme. INDEPENDENT CLAIMS are included for:    (1) producing R-lactic acid comprising producing R-alkyl lactate, and converting the R-alkyl lactate into R-lactic acid;    (2) producing oligomeric R-lactic acid comprising producing R-alkyl lactate or R-lactic acid, and converting the R-alkyl lactate or R-lactic acid into oligomeric R-lactic acid;    (3) producing R,R-lactide comprising producing R-alkyl lactate, R-lactic acid or oligomeric R-lactic acid, and converting the R-alkyl lactate, R-lactic acid or oligomeric R-lactic acid into R,R-lactide;    (4) producing poly-R-lactic acid comprising producing R,R-lactide, and converting the R,R-lactide into poly-R-lactic acid;    (5) producing stereocomplex lactic acid comprising producing poly-R-lactic acid, and combining the poly-R-lactic acid with poly-S-lactic acid to produce stereocomplex lactic acid; and    (6) producing alkyl S,S-lactyl lactate comprising the step (a) as above per se, and reacting at least a portion of the intermediate with an alkyl alcohol to produce alkyl S,S-lactyl lactate and alkyl R,R-lactyl lactate, where the alkyl R,R-lactyl lactate is reacted with alkyl alcohol in the presence of an enzyme to produce alkyl R-lactate.