I’m planning to make my own fermented products at home: sauerkraut, kimchi and kefir. So far, I am swotting up with a book I bought from one of our longstanding Zestt retailers, @Health2000Sunray (in Dunedin): Ferment for Good, Ancient Foods for the Modern Gut (by Sharon Flynn). I love how different ferments amplify different bacterial species depending on the source material and fermenting conditions.
It got me thinking about probiotics in general, and I realised I haven’t been very good at telling the story of the probiotics we use and how they spring into action:
- When your Zestt lozenges arrive, the oral probiotics are dormant. BLIS K12™ and BLIS M18™ (Streptococcus salivarius) are freeze-dried as live cells, dehydrated into a stable powder so they survive at room temperature - alive but metabolically paused.
- When you put the lozenges in your mouth, your saliva revives them. Water re-enters the cells, and the probiotics’ membranes and enzymes become functional again. They resume normal metabolism within minutes. Saliva also supplies the sugars and amino acids for the probiotics to feed on, and the honey in the lozenge gives them an energy source.
- The live probiotics attach to your mouth and throat. Streptococcus salivarius is a natural resident of the human mouth, so it has surface proteins that let it stick to your cheek lining, tongue and throat tissue. This is why dissolving a lozenge slowly is a good idea - resist the urge to crunch them, as I sometimes do! The longer the bacteria are in contact with your mouth’s surfaces, the longer they have to find a foothold.
- The live probiotics start producing their "weapons." Once the probiotics are settled and multiplying, BLIS K12 secretes bacteriocins called salivaricin A2 and B, and BLIS M18 produces its own salivaricins plus enzymes (dextranase and urease) that break down plaque and neutralise acid. These compounds inhibit competitors such as Streptococcus pyogenes (strep throat) and Streptococcus mutans (tooth decay).
A few practical things to note:
- Take your lozenges after brushing your teeth, last thing at night, or after your breakfast, so the bacteria have time for undisturbed contact in your mouth.
- Avoid antiseptic mouthwashes, which kill the probiotics along with everything else.
- Let the lozenge dissolve fully rather than chewing; the mouth and throat are the target, not the stomach.
- Antibiotics will knock your oral probiotic population back, so re-dose after you take a course of antibiotics.
Reading my new book has reminded me that fermentation and probiotics are the same story told at different scales. In a jar of sauerkraut, you establish the right conditions for bacteria to thrive. In your mouth, a Zestt lozenge does something similar: it delivers the right species, and saliva provides the conditions for the bacteria to get to work.
So the next time you suck on a Zestt Lozenge, think about the army of helpers you are waking up!
And I’ll let you know how my food fermentation journey goes (I am sure there will be a few disasters).