Killer stomach acid: Who can survive the acid bath?

A spoonful of fresh yogurt or a forkful of sauerkraut, and a journey reminiscent of an epic drama begins inside us. But while we are still enjoying the taste, billions of microorganisms are already heading for what is probably the most dangerous barrier in evolution: the stomach.

There is often a persistent myth that stomach acid, like a biological blast furnace, mercilessly destroys every bacterium. But modern microbiome research paints a much more nuanced picture. It is a fascinating interplay of chemistry, physics, and perfect timing that determines who actually reaches the “overcrowded paradise” of the large intestine alive.

In this episode, we dive deep into the human system and accompany our microbial helpers through the various stages of digestion. We reveal the secret behind the window of survival and explain why the so-called food matrix can mean the difference between a safe submarine and a safe end for a bacterium. From the aggressive environment of the parietal cells to the chemical task force in the small intestine to the question of why permanent colonization of probiotics is usually not the goal at all.

A search for clues to the reality behind fermented foods, in which one thing becomes clear: “arriving” in the gut means something completely different than most people assume.