Lactic acid Fermentation Process

Czyzowska, A., Klewicka, E., and Libudzisz, Z., The influence of lactic acid fermentation process of red beet juice on the stability of biologically active colorants, Eur. Food Res. TechnoL, 223, 110, 2004. 

MUR 09] Murariu M., Da Silva Ferreira A., Bonnaud L., et al, Calcium sulfate as high-performance filler for polylactide (PLA) or how to recycle gypsum as by-product of lactic acid fermentation process . Composites Interfaces, vol. 16, p. 65,2009. 

This chapter focuses on the microbial fermentation process for lactic acid production. The first commercial operation was set up by Avery in the USA in 1881. Microbes contain enzyme(s) called LDH which can convert pyruvic acid to lactic acid. Depending on the particular microbe and the specificity of its LDH, the lactic acid fermentation process can produce rather pure d-LA or l-LA with high optical purity, or a mixture of them with low optical purity. Genetic engineering tools can be used to knockout the d-LDH gene(s) in the production strain to improve the optical purity of its l-LA fermentation process. 

Luo J, Xia L, Lin J, Cen P. Kinetics of simultaneous saccharification and lactic acid fermentation processes. Biotechnol Prog YI l fiT (sl-1. 

Vaccari et al. also applied NIR to the control of the lactic acid fermentation process (20). To get a chemical parameter such as the concentrations of the substrate, nutrients, and biomass, an on-line NIR system has been introduced to the quantitative determination of glucose, lactic acid, and biomass in real time during fermentation. The spectrophotometer, InfraAlyzer 450 (Bran-Luebbe Co., Germany) equipped with a cuvette for liquid was used. Lactic acid and glucose concentrations in the broth were measured with HPLC as a conventional method. The cell (biomass) concentration was measured conventionally by a drying method. A set of 45 samples of broth was used as the calibration sample set to create the calibration equation. Lactobacillus easel was cultivated in a fermentor with working volume of 3 1. The calibration equations... 

In the lactic acid fermentation process, the lactic acid bacteria are grown under anaerobic conditions with low energy production. Such low-energy yield bacteria grow slowly compared... 

Most of the commercial fermentation processing of lactic acid in batches requires 3 to 6 days to complete sugar concentrations of between 5—10% are used (Garlotta, 2001). Many lactic acid fermentation processes have been patented over the decades. Most of these patents are restricted in the disclosing of the fermentation process, as they also provide the lactic acid separation technologies. In US patent 6 319 382 Bl, by the inventor Norddhal (2001), whey protein is added as a nutrient substrate for the lactic acid bacteria and protease is added to the fermentor to enable hydrolysis of protein to supply amino acids during the fermentation process. In addition, the aqueous... 

A new method for the preparation of soy sauce has been developed. The new scaled-up method divides the moromi process into two processes autolysis and fermentation. Because of the utilization of high temperatures, the new process permits the production of a NaCl free autolyzate from koji. Division of the fermentation process into two separated processes permit better control of lactic acid fermentation and alcohol fermentation processed which used to require great skill. The new scale-up procedure for soy sauce production yields a product in half the time required by the traditional (conventional) method and still produces a soy sauce with high levels of the desirable Bavor component, glutamic acid. Utilization of this protocol by the soy sauce producing industry should have significant economic impact to bo producers and consumers. 

The product of this metabolic sequence, pyruvate, is a metabolite of caitral importance. Its fate depends upon the conditions within a cell and upon the type of cell. When oxygen is plentiful pyruvate is usually converted to acetyl-coenzyme A, but under anaerobic conditions it may be reduced by NADH + H+ to the alcohol lactic acid (Fig. 10-3, step h). This reduction exactly balances the previous oxidation step, that is, the oxidation of glycer-aldehyde 3-phosphate to 3-phospho-glycerate (steps a and b). With a balanced sequence of an oxidation reaction, followed by a reduction reaction, glucose can be converted to lactate in the absence of oxygen, a fermentation process. The lactic acid fermentation occurs not only in certain bacteria but also in our own muscles under conditions of extremely vigorous exercise. It also occurs continuously in some tissues, e.g., the transparent lens and cornea of the eye. 

Fio. 5.19. The lactic acid fermentation. The reaction sequence results in two molecules of lactic acid, two molecules of ATP and a balanced redox process... 

LUEDEKING, R. and Piret, E. L. J. Biochem. Microbiol. Technol. and Eng. 1 (1959) 393. A kinetic study of the lactic acid fermentation. Batch process at controlled pH. 

Combined use of lactate fermentation and ED separation has been proposed to overcome the main drawbacks of this fermentation process, that is, low microbial acidic productivity and expensive downstream processing of lactic acid fermentation broths (Boyaval et al., 1987 Hongo et al., 1986 ... 

Simultaneous L-lactic acid fermentation (by Rhizopus oryzae immobilized in calcium alginate beads) and separation was carried out using a three-phase fluidized-bed bioreactor as a fermenter (F), an external electrodialyzer as a separator, and a pump to recycle the fermentation broth between the bioreactor and the separator. In this way, the experimental specific lactate productivity and yield practically coincided with those obtained in the CaC03-buffered fermentation process (Xuemei et al., 1999), thus confirming the capability of the combined system to alleviate product inhibition without any addition of alkali or alkali salts. It was also shown that the adoption of ED-F for the production of inoculum reduced variability in inoculum quality, thus shortening the length of the lag phase of L-lactate production practically to zero as compared to that observed using an inoculum... 

Lactic acid fermentation occurs when lactate is the end product of fermentation. Coupled with glycolysis, lactic acid fermentation can generate ATP from ADP and provide energy for cellular processes. The fermentation step in lactic acid fermentation generates NAD+ from NADH + H+, and the NAD+ cycles back to the glycolysis process. The lactic acid fermentation cycle is illustrated in Figure 4.10. 

Alcoholic fermentation occurs when the end product is ethanol, as shown in Figure 4.11. In this process the pyruvate is first converted enzymatically to acetaldehyde. The conversion of acetaldehyde to ethanol produces NAD+ from NADH + H+, and the NAD+ is cycled through the glycolysis process. As with lactic acid fermentation, the glycolysis process produces usable energy contained in two molecules of ATP produced for each molecule of glucose metabolized. 

The remaining water is finely distributed across the fat phase by a kneading or extrusion process. During this phase aroma compormds, for example, lactic acid fermentation extracts, can be added to modify the taste profile in case sweet cream was used to produce the butter. 

Manufacture. The natural zymotechnics process (lactic acid fermentation) When lactic acid is formed in milk by the action of lactic acid bacilli, the casein coagulates due to the acidity of the lactic acid. There are several other methods. 

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