Abstract: The present invention relates to a method for the purification of an &agr;-hydroxy acid on an industrial scale, in which an &agr;-hydroxy acid with a colour (fresh) of not more than 10,000 APHA units is subjected to (a) a crystallization step followed by (b) a distillation step.

Abstract: This invention relates to the controlled acidification of food products, like dairy products, meat etc. By acidification, food products are protected against harmful microbiological cultures and food can get a certain texture, e.g. the coagulation of dairy products or the drying and texture formation of dried sausages. The invention comprises a new method of acidifying food products in a controlled way. Using lactic- or glycolic acid oligomer/derivatives and salts or derivatives thereof achieve this controlled acidification.

Abstract: The present invention relates to a method for the purification of an &agr;-hydroxy acid on an industrial scale, in which the method involves: (a) subjecting an aqueous stream containing mainly &agr;-hydroxy (1) to an extraction step, with the formation of an aqueous place containing mainly &agr;-hydroxy acid (2), (b) concentrating the aqueous phase containing mainly &agr;-hydroxy acid (2) by means of evaporation of water under reduced pressure, with the formation of a concentrated &agr;-hydroxy acid solution in water (3), and (c) subjecting the concentrated &agr;-hydroxy acid solution (3) to a crystallization, with formation of pure &agr;-hydroxy acid (4), where (i) the concentrated &agr;-hydroxy acid solution (3) is directly cooled in a melting crystallization device, and/or (ii) the concentrated &agr;-hydroxy acid solution (3) is diluted with water and crystallization is brought about in one or more cooling crystallization devices and/or evaporative crystallization devices, and/or (iii) crystallization is b

Abstract: The invention relates to a method for the purification of a fermentatively prepared &agr;-hydroxy acid on an industrial scale, in which an &agr;-hydroxy acid with a colour (fresh) of not more that 10,000 APHA units is subjected to at least two crystallizaion steps, with the crystallization steps being carried out in cooling crystallization devices, melting crystallization devices, evaporative crystallization devices and/or adiabatic crystallization in devices.

Abstract: The present invention relates to a method of industrial-scale purification of lactic acid, the method including the steps of: (a) reduced-pressure distillation of a concentrated lactic acid solution having a total acid content of at least 95 wt % and a content of monomeric lactic acid of at least 80 wt %, based on the concentrated lactic acid solution, the ratio between the lactic acid enantiomers in the concentrated lactic acid solution not being equal to 1; and (b) subjecting the concentrated lactic acid solution to a crystallization to form a pure lactic acid. The invention also relates to the lactic acid or the lactic acid solution obtained via this method, and the use thereof.