Production of lactate

PURPOSE: To obtain a lactate used as a raw material of a polylactide for a biodegradable packaging material by fermenting a mixture containing a sugar, converting the obtained lactic acid to an alkaline earth metal salt, adjusting pH with NH 3 and CO 2 , removing the precipitate and esterifying the purified lactate. CONSTITUTION: This lactate as an intermediate for manufacturing a lactide, is obtained by inoculating a lactobacillus (e.g. lactobacillus casei ATCC27139) in a mixture containing sugar (e.g.; glucose) for fermenting, adding an alkaline earth metal carbonate (e.g. ; calcium carbonate) or a hydrogen carbonate salt for neutralizing at least upto 90 mol.% of lactic acid obtained during the fermentation, adjusting the obtained fermentation liquid at pH7-13 by the addition of NH 3 and CO 2 , then removing the precipitate, adding a tertiary alkylamine (e.g.; tributylamine) to the produced ammonium lactate solution, and esterifying the purified aommonium lactate solution by adding an alcohol. COPYRIGHT: (C)1995,JPO