I found an interesting research paper from 2018., titled: Carrot juice fermentations as man-made microbial ecosystems dominated by lactic acid bacteria (doi: 10.1128/AEM.00134-18).

The quote below is what sparked an idea in me to start a small series of fermentation experiments at home. The what: fermentation of carrots (and, in time, carrot juice). The why: pure enjoyment and to see if I can create something I’d consume regularly.

Quote from the aforementioned paper (Note: LAB = Lactic Acid Bacteria/Bacteriae):

Participants were asked to ferment their own carrots (either from their garden, supermarket, or organic origin), in their own jars and kitchens, according to a standard procedure, after attending a workshop. The resulting culture-dependent data of these household fermentations, combined with those of carefully monitored laboratory fermentations, showed that spontaneous carrot juice fermentation is a consistent microbiological process. It is characterized first by the presence of Enterobacteriaceae, followed by a clear shift in microbial abundances, ultimately resulting in a dominance of LAB species. This drastic shift in microbial communities took place between days 3 and 13 of fermentation, and acidification by the LAB led to a decrease in pH below 4.6, the widely accepted food fermentation safety threshold.

The researchers found that the dominating LAB species were mainly Leuconostoc spp. and Lactobacillus spp. These LAB have a myriad of positive effects on human gastrointestinal tract, but that topic is beyond the scope of this post.

This is a fun (and very likely, tasty!) experiment using only three ingredients: carrots, water and salt.

Carrots were bought in a local supermarket, peeled and cut into approx. 15 cm long and 1-2 cm wide sticks, and then stacked into a clean jar in such a way that there is minimal space between them (this is so that the carrot sticks don’t float to the top when brine is added).

Tightly packed carrot sticks

One liter of 2% (by weight) salt brine was made by combining 1 kg of water with 20 g of table salt. The brine was then poured in the jar with the carrot sticks. A jar lid was placed loosely over the jar and the prepared jar was placed to sit at room temperature (approx. 21 ± 2 °C).

The first experiment is a simple spontaneous fermentation. After assessing the results of this experiment (I’ll let the fermentation go for a minimum of 3 and a maximum of 7 days), I’ll probably start a new batch: two jars, one like before, the other one with a tablespoon or two of sauerkraut juice (commonly known as rasol in my country).