| 摘要 |
<p>The invention relates to a process for obtaining the technical L-lactic acid used in the food industry. According to the invention, the process consists in the whey fermentation, it having a content of 75 g/l lactose, in the presence of a bacterial mass of Lactobacillus casei, immobilized in calcium alginate, with 5% chitosan, at a temperature of 45...50°C, with an addition of 1% yeast extract, for 24 h, afterwards the biomass is separated by decantation, and the fermentation medium is acidified with HCl 1 M, further on, the lactic acid is isolated by two successive extractions by using n-butanol, the organic phase is mixed with sodium hydroxide while stirring, for 45 min, and after 1 hour the phases are separated, wherefrom the aqueous phase containing sodium lactate is transformed into lactic acid by neutralization with a HCl 1 M solution, and, at the end, the solution is concentrated up to a content of 60% lactic acid.</p> |
