Updated: Aug 6, 2019
A study found 100 million microbes were present on apples and there is no reason to believe even more bacteria would be present on peaches, apricots, strawberries, blueberries, raspberries, wild brambles and all sorts of other fruits picked and eaten from fields, hedgerows and moorlands. These findings put into perspective the illogical commercial interest in probiotics as opposed to prebiotics. (Probiotics are symbiotic live bacteria and PRE-biotics are the substrates that feed them.)
There are thousands of different microbes in our guts and these are found everywhere, in the air, dust, skin and surfaces of foods that we eat. In the presence of appropriate food, these microbes multiply, live and die with life cycles measured in seconds and minutes, in turn the microbes themselves become food for other species of bacteria, and most important, breakdown products of microbes, their protoplasm, DNA, vitamins, cofactors, fatty acids, etc. become an important food for us, their hosts.
Take Home Point: Save your money on probiotics, instead focus on prebiotics: eat fresh or picked yourself organic fruits and make sure you get plenty of fiber to keep the fermentation process going in your hind gut where all sorts of nutrients and vitamins are produced by our microbiome for free.