There's a pH war in my mouth, why can't toothpaste and food be friends?

good chance the difference is the sodium lauryl sulfate, which is a surfactant, and has removed the film layer (called the pellicle) from your teeth. the pellicle reforms, it just takes longer because the commercial toothpaste has been designed with this soap to give you that long lasting clean feeling.

Definitely SLS. Interestingly, SLS is totally useless for cleaning teeth. It's a lathering agent, and they put it in toothpaste because we expect toothpaste to be foamy. They put the same crap in shampoo to make it foam.

I'm sure Dr Ellie Phillips would be up for answering your question, considering that she heavily promotes crest cavity protection as part of her system (and she seems to have genuinely good reasons for doing so). http://askdrellie.blogspot.ca/

Thanks everyone! I knew SLS/SDS were foaming agents, but I had no idea that's what contributed to a temporary alteration of taste. With your leads I found a couple of articles that explain more of the science behind it. Anecdotally, I found some kids toothpaste, and it must contain less SLS because my morning taste clash has been a bit milder. Addressing sweet taste buds: Here's a quote from a http://cro.sagepub.com/content/9/3/267.full.pdf in Chemosensory Function and Disfunction: "This effect on sweet taste, but not on other taste qualities, is transitory and can be explained by the action of the detergent sodium dodecyl sulfate (SDS), a common ingredient in toothpastes (Rollin, 1978; Toyano and Nabeshima, 1983). SDS apparently denatures the sweet taste receptors. Loss of sweet-tasting lasts for several minutes, during which time the sweet receptors may become renatured (DeSimone et al., 1980)." Yes, the references are to works from the 1980s but from what I've read in other places, that's still the generally accepted explanation. (And I can't access the journal database I usually go to right now..) This article also has some nice basic schematic diagrams of the cellular level. And addressing bitterness and other details from http://science.howstuffworks.com/life/human-biology/orange-juice-toothpaste1.htm: "The likeliest culprit for the offensive reaction is the foaming agent found in almost all toothpastes. Sodium lauryl sulfate (SLS) is a surfactant -- a sudser -- added to toothpaste. It creates the froth that toothpaste becomes after you begin brushing by lowering the surface tension of the saliva in your mouth and allowing bubbles to form. While it aids in spreading the toothpaste throughout your mouth, it also creates the impression of cleanliness; a mouthful of foam just feels cleaner. "But SLS has other properties, too. For one, it suppresses your sweet receptors, so it has a dampening effect on the generally sweet taste of orange juice. In addition, SLS destroys phospholipids. These fatty compounds act as inhibitors on your bitter receptors. So by inhibiting sweet receptors and destroying phospholipids, SLS dulls the sweetness and promotes the bitter taste in orange juice."

And, this 2008 clinical dental text, http://books.google.ca/books?id=fZfXWhSmG1UC&lpg=PA275&dq=pellicle%20teeth%20sds&pg=PA275#v=onepage&q=pellicle%20teeth%20sds&f=false, has a few paragraphs about SDS.