You don’t need to boil salmonella to kill it:

https://ourdailybrine.com/wp-content/uploads/our-daily-brine...

You’ll have to work pretty hard to make a credible cup of tea with viable salmonella in it.

The more sensitive "proper" teas are well into the danger zones e.g. gyokuros tend to be brewed between 50C and 60C, and with brewing times under 3mn.

Never really heard of hard thermal limits for herbals though, in my experience they're more resilient and less caring, and you can long-boil most of them like you'd do a middling black tea.

By that standard, you should be really careful with matcha — you mix it will non-bacteria-killing water and then drink the whole thing!

I don’t know whether most pathogenic bacteria can survive prolonged dry storage conditions, though. And, if you’re worried, you could likely pasteurize your fancy tea by heating it, dry, to 60C or so for a while.

I’m not even remotely worried about tea-borne salmonella, just pointing out that per your link for higher-grade green teas the brewing temperature x brewing time is well below what’d be needed to destroy it.

While I usually boil tea water, I just remembered I sometimes do cold brew tea (overnight with straight tap water). No gastrointestinal discomfort yet.

One thing to keep in mind is that some teas (as in made from Camellia Sinensis leaves) are processed using a pan/ceramic firing or steaming step to stop the leaves from oxidizing. I'm not sure how hot it gets but there is a heating step that might affect the viability of some pathogens.

It makes sense that herbal teas might be more susceptible to pathogen contamination if they don't go through that.

Of course there's plenty of steps along the way to contaminate tea, and chemical contaminants are different. But boiling water isn't the only heating step for some teas.

Having said that, I generally just use boiling or near boiling water for all my tea. I've tried all sorts of combinations of temps with many many different varieties of tea and have decided that the tea variety, amount used per serving, and length of steeping make much more of a difference than the temperature. I also think I just like bold-flavored tea (I do like bitter flavors quite a bit, and have been known to seek them out even when I was too young to really be aware of a pattern with it).