Microbiology Studies Show The Difference Between Store Kefir And Home Brewed Kefir

A team of four microbiology research students, who had no knowledge of kefir prior to their lab work, found 58 billion CFU (colony forming units) per cup of home brewed kefir. They found the CFUs of store brand kefir numbers comparable to the home brew, but the story doesn’t end there.

However, further research showed the difference was remarkable.

Store brands are pasteurized after the fermentation process. Third year microbiology student Sylvia Stankov said, “A lot of those microbes aren’t actually there, they’re killed off in the process.” Pasteurization is necessary for kefir on the store shelf. If the product is allowed to continue brewing it will bulge in the packaging or explode due to fermentation pressure.

This pasteurization limits the spectrum of beneficial microbes, the whole point of eating probiotic foods.

The team has been researching under Professor Monika Oli, Ph.D., Lecturer at the Department of Microbiology and Cell Science at the University of Florida. They have been studying goat milk kefir from Glades Ridge Goat Dairy, owned by Greg Yurish. 

{We are taking a leap of faith and have added a donate button instead of using advertisers. Advertisements have been removed from this page to make your reading uninterrupted. If you learn something here, please donate so we can keep offering these posts. This post contains affiliate links, which sometimes pay for this site}.

Professor Monika Oli said, “I did an experiment with Lifeway, Publix brand and my own kefir and I found a 10 to the 7th difference in the live active cultures, a 10 billion bacteria difference between the store-bought and homemade (made from raw goat’s milk). If you buy the organic health brands, they’re a little bit better but they also have the sugars in them. The Lifeway had very little in it, by the thousand CFUs compared to 10 billion or so.”

Oli goes on to say, “We’ve (studied) yogurt many times before; commercial yogurt has barely nothing in it. Some are completely dead. It’s basically useless to eat commercial yogurt.”

The microbiology class went further with their kefir studies and identified different strains along with the CFUs.

Pre-med student Beau Freedman said, “We performed serial dilutions from 10 to the negative 5th to 10 to the negative 10th and we plated that on MRS and PDA (potato dextrose agar) plates for different bacteria and yeasts. We were able to isolate four different bacteria and three different yeasts just on those plates.”

He went on to say, “They each have their own health benefits, they all complement each other. We sent them off for sequencing after doing a PCR with doing a 16S for bacteria, 18S for the yeast. We found Lactococcus lactis, leuconostoc lactis, Enterococcus durans, Gluconobacter japonicus, Saccharomyces unisporus, Saccharomyces cerevisiae, Kluyveromyces marxianus.”

Pre-med student Parker Novak said, “Lactococcus lactis is commonly used for fermentation.”

Genome Research says, “Lactococcus lactis is a nonpathogenic AT-rich gram-positive bacterium closely related to the genus Streptococcus.” This beneficial strains kill off the pathogenic strains. Many researchers are pointing to kefir for reversing overgrowth of pathogenic Streptococcus, which is responsible for the recent rise in PANDAS. Click here to read more. 

They go on to say, “A complete set of late competence genes is present, indicating the ability of L. lactis to undergo DNA transformation. Genomic sequence revealed new possibilities for fermentation pathways and for aerobic respiration. It also indicated a horizontal transfer of genetic information from Lactococcus to gram-negative enteric bacteria of Salmonella-Escherichia group.”

 Microbe Of The Week at the Missouri University of Science and Technology says, “The bacterium is also being looked at as a potential oral vaccine for developing countries against Streptococcus pneumoniae.”

Leuconostoc lactis is thought to only form from dairy origin. The American Journal of Medical Sciences says, “L. lactis colony morphology resembles a Streptococcus.” To read more on these beneficial strains click here.

The Journal of Clinical Microbiology says, “Leuconostoc lactis is a streptococcus-like strain. Our L. lactis strains possibly represent a variant from those of a less versatile nature found in dairy products. Their low incidence in clinical material indicates that they are probably not normal inhabitants of humans, while in general the common isolation of Leuconostoc strains from meat products coupled with the divergent characteristics of our strains, indicates that the distribution of L. lactis outside dairy environments cannot be overestimated.”

Leuconostoc lactis and Enterococcus durans both fall under the same questionable category. They are thought to be pathogenic in the hospital setting, however, when found in fermented foods they prove to be beneficial in rebuilding the microbiome. Research is still needed to determine the exact status and purpose of these strains, which are still not fully known. Many species have good and bad strains such as E. coli. Good E. coli assists in digesting lactose. Click here to read more.

Enterococcus durans often presents a problem where it is identified incorrectly. “E. durans is not regarded as particularly pathogenic to humans and therefore VRE isolates of this species are not regarded as having the same significance for infection control as E. faecalis and E. faecium,” says the Journal of Antimicrobial Chemotherapy. Yet it is consistently found where repair is taking place specifically as, “DNA repair protein.”

The Medical University of South Carolina, BMC Microbiology reports Enterococcus durans is a tyramine producer which, “Was found to be mediated by a transcription antitermination system, whereas the specific induction at acidic pH was regulated at transcription initiation level.”

Critical Reviews In Biotechnology says, “The first step of acetic acid production is the conversion of ethanol from a carbohydrate carried out by yeasts, and the second step is the oxidation of ethanol to acetic acid.”

Ember Courtney, a pre-dental major says, “Sacromyaces was the yeast that we found. We found two different strains. It’s generally

used in most store bought probiotics. We found the Enterococcus durans stimulates gastro intestinal conditions and resists antibiotic damage. K. marxianus has been implicated in controlling the immune system by inducing pro-inflammatory responses which facilitates growth of bifido bacteria.”

Courtney stresses the importance of the synergistic effect of using multiple species at one time. They work collectively, impacting the microbiome.

Stankov says, “We found a really interesting statistic for one of our yeasts – there are antibodies against this yeast found in 60-70 percent of patients with Crone’s disease and in 10-15 percent of those with ulcerative colitis.”

Oli says, “One of the yeasts, clurglomysis is known to produce lactase so it breaks down lactose. Basically the kefir is naturally lactose free.”

S. cerevisiae is reported by the research team to have, “Positive effects on growth and production of Lactobacilli. S. cerevisiae has been used as a probiotic to treat bacteria-induced diarrhea.”

Stankov said, “We found prophylactic consumption of kefir can help with lactose intolerance. It’s suggested in multiple sets that we looked at, that people who have lactose intolerance consume kefir to build up a better tolerance to lactose.”

She says consuming probiotic foods is rebuilding to a damaged microbiome. “You’re re-seeding what you have in your gut. That facilitates whatever you eat you can digest it; you get more vitamins that you need.”

Oli questions the ability to retain the beneficial strains. As the bacteria pass through your system, they are transient in nature, feeding good bacteria as they pass through the tract. She says, “It doesn’t stay in your intestines. It depends on where you are in your gut health. If you have it regularly it doesn’t matter if they stay or not because you’re replenishing them.”

Stankov says her findings show increased numbers of all species contribute to overall health. 

Making your own kefir is simple and inexpensive. Purchasing live grains can be done by clicking here or here or here other packets can be purchased here (a powder starter) or here (powdered milk in addition to milk).

To read more click here.

Stay tuned for the follow up to this article.

*Nourishing Plot is written by Becky Plotner, ND, traditional naturopath, GAPS who sees clients in Rossville, Georgia. She works as a Certified GAPS Practitioner who sees clients in her office, Skype and phone. Since her son was delivered from the effects of autism (Asperger’s syndrome), ADHD, bipolar disorder/manic depression, hypoglycemia and dyslexia through food she continued her education specializing in Leaky Gut and parasitology through Duke University, finishing with distinction. This is not a news article published by a paper trying to make money. This blog is put out by a mom who sees first hand the effects of nourishing food vs food-ish items. No company pays her for writing these blogs, she considers this a form of missionary work. It is her desire to scream it from the rooftops so that others don’t suffer from the damaging effect of today’s “food”.

“GAPS™ and Gut and Psychology Syndrome™ are the trademark and copyright of Dr. Natasha Campbell-McBride. The right of Dr. Natasha Campbell-McBride to be identified as the author of this work has been asserted by her in accordance with the Copyright, Patent and Designs Act 1988.