Fermentation, one of many oldest meals manufacturing and preservation methods, has seen an enormous revival lately. From craft beers and kombucha to yoghurt, sauerkraut and pickles, fermentation is central to producing these meals and drinks. There are various kinds of fermentation, one of which is lactic acid fermentation.
Lactic acid (also called lactate) is finest recognized for the burning sensation we really feel in our muscle tissues when exercising, which acts as a sign to the physique to decrease the depth of the exercise.
In terms of fermentation and meals storage, lactic acid is produced by lactic acid micro organism – vital for making a low pH setting that stops meals spoiling. Some lactic acid micro organism produce lactic acid solely. Others produce lactic acid in addition to a wide selection of different natural acids, which additional acidify and create an setting that’s freed from oxygen. Lactobacillus brevis is one such bacterium.
This microorganism, when considered below the microscope, may be described as rod-shaped with rounded ends. It’s additionally Gram constructive – which means that it stains an indigo color when examined utilizing the Gram staining method. It thrives at a temperature of 30-40 levels Celsius and a barely acidic pH (pH 4-6).
Most significantly, it’s a celebrity on the subject of fermentation – producing lactic acid, acetic acid and carbon dioxide throughout the course of.
Why would possibly you need a microbe that makes natural acids and carbon dioxide?
One of many a number of meals merchandise the place Lactobacillus brevis is of course discovered is sauerkraut. Historically produced sauerkraut has lengthy been recognized to be a good supply of lactic acid micro organism. These micro organism are additionally present in pickles, in the tibicos grains used to make kefir and are a pure part of the intestine microbiome.
Throughout sauerkraut preparation, Lactobacillus brevis and different lactic acid micro organism, akin to Lactococcus and Leuconostoc species, assist to ferment cabbage. Throughout this course of, the micro organism break down sugars within the cabbage, producing carbon dioxide and lactic acid, giving rise to the distinctive attributes of this fermented product.
After I open a jar of sauerkraut, I’m all the time pleasantly stunned by the fizzing sound and look of the jar contents. It’s the manufacturing of the carbon dioxide that ends in the spectacular effervescence. The lactic acid and acetic acid are chargeable for the tangy, barely bitter or acidic style.
Additionally, as a result of these are natural acids, they naturally decrease the pH of the fermented cabbage – which means that the majority contaminating microorganisms that favour a impartial pH will not be part of the setting. Lactic acid micro organism additionally produce antimicrobial compounds akin to bacteriocins, which stop the expansion of different contaminating micro organism. These results make fermentation a wonderful preservation method.
By way of intestine well being, the microbiome is complicated. It’s distinctive to every individual and may be influenced by a number of elements, together with food regimen. Some lactic acid micro organism have been reported as being probiotic – which means they’re dwell microorganisms that enhance intestine well being. Additionally, though sauerkraut is promoted as containing probiotic micro organism, questions stay concerning the viability of those micro organism on the time of consumption – and whether or not they’re current in ample numbers to be helpful.
Simply because the microbiome itself is an ever-changing panorama, so too is that this discipline of analysis as investigations proceed to be carried out. However in the event you do determine to hitch me in including sauerkraut to your food regimen for its distinctive style and texture – and attainable well being advantages – bon appétit.
Leanne Timpson is Lecturer in Microbiology, Nottingham Trent College.
This text was first printed on The Dialog.