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Kombucha in a petri dish - yeast only?
I made kombucha and added lots of broccoli sprouts in it. Then - after 2 months I sent a bottle to lab to check if the bacteria was still alive. I am not sure if this (picture) is only yeast? Is it possible to ask the lab to find CFU? If this is only yeast, is there no live/viable probiotic bacteria here? (First petri is when the kombucha was heated to 30 degrees, the other one is 22 degrees - they could not count it at all
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17 Replies
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Ask the lab. The used culture medium determines which germs can or can’t grow. There are media which are selective for bacteria or for fungi and such which allow growth of both.From afar, these dishes look like colonised by bacteria rather than yeast but again, the lab technician who actually holds these plates (held them under a microscope) should be able to tell your more.Edit: upss, just figured out that I can get a close-up. Well, could be either of both, bacteria or yeast… (not helpful, I know) -
Thank you Pharma! I asked for probiotic bacteria, so maybe (hopefully) it is bacteria. But I will ask them
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“Probiotic” is an arbitrary definition. A living microbe or active spore is pro-bios = for life, no matter whether it’s “healthy” (again, not a clearly term) or pathogenic. Usually, probiotics are either part of commensal/symbiotic microbes or transient guests in/on our body which allegedly have “beneficial” effects. Also, a probiotic product should deliver living microbes to its target (skin, guts etc.). Since E. coli is usually a commensal/symbiotic intestinal bacterium, it may be considered “probiotic” depending on the intended use (i.e. against diarrhoea), a pathogen if it’s one of certain potentially harmful strains, or a contaminant in products used for other purposes (e.g. cosmetics, eye-drops, intimal care…).
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I checked the paper for the picture here - it is bacteria, but is there any way to check if these bacteria was alive?
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It grows on a petri dish so it was very much alive! Dead bacteria don’t show up on petri dishes.
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yes of course
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More about probiotics: The live bacteria in for example kombucha are in a “sleeping” mode when it is in the bottle because of pH of 3,2 (and also because it is no food for the bacteria) It turns alive when you feed it (for example drink the kombucha). But will the same thing (sleeping mode) if I raise the pH to 7.6? Or will such a high pH kill the bacteria? I like to spray it on horse
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Low pH also favours lactic and propionic acid bacteria which are one of the main “probiotic” microbes. During fermentation, these lactobacilli and company displace other unwanted germs, hamper their growth by producing lactic (and/or propionic) acid which lowers pH, and use up most of the sugars = no more food = no further growth. If you raise pH during fermentation, you get a higher degree of fermentation but also run a higher chance of screwing up = microbial contamination with other germs. Raising pH after fermentation might “resurrect” said unwanted germs before lactobacilli and again, you’ve lost the game. Adding a preservative to stop those will stop all and probably reduce the effectiveness of your product.
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If you raise pH during fermentation, you get a higher degree of fermentation
AHA!! Finally I discover why I was told to add Calgon water softener to my fermentation barrels in Saudi … no don’t ask what I was making. -
Belassi said:… no don’t ask what I was making.
Obviously, I have to ask: What were you making?
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Ethanol, of course… storage of 97% ethanol is not a simple task. The best thing is glass dewars. (Plastics leach into pure ethanol). . . drives down the coast road to the Coca Cola plant. “Can I have some of your leftover glass syrup bottles please?”
Unexpected question: “What do you want them for?”
“Er… well… putting ships in bottles! It’s my hobby!”
(Very skeptical stare.) I see … goes and gets several.
Days later at a party I met an American guy also into ethanol production. “So I went to the Coke plant and asked for empty dewars.”
Me: “Oh really?”
“Yes. And they asked what I wanted them for.”
Me: (laughing) what did you tell them?
“I said I was going to use them for putting ships in bottles.”
Me: (really laughing now) and what did they say to that?
“He didn’t seem to believe me but he gave me them anyway.” -
How much can I raise the pH after fermentation of my fluid (mainly different lactic acid bacteria) so it is safe to spray it on my horse?
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Why would you want to raise pH?
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Because pH 3,2-3,5 “burns” when I spray on wounds and skinproblems
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Ah, I see. You want to spray living microbes on injured skin… hmm… not sure how I should feel about that… I know, using fly maggots as would dressing is an actual thing but an undefined mixture of microbes… If ever, you would have to use a pre-defined inoculum of known, non-pathogenic/beneficial yeast and then run a test series at the end (for every batch you make!) to determine which exact microbial species are really in there. Or you sterile filter your product (with or without lysis), adjust pH to your liking, and apply something which is truly safe though no longer a probiotic but a so called postbiotic.
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yes, I know Pharma - this is for my horse - he also (and me) drinks probiotics every day!
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Drinking it is certainly okay and very healthy but it’s not at all comparable to putting it on injured skin.
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