Thanks for posting this. I also find dat when I leave a very alkaline soap on my face too long before rinsing it off, my face begins to have a very putrid, sour odor. You're right - certain range of skin PH (influenced by soap PH) can lead to odor. Im also suspecting that staphlococcus epidermis (SKIN BACTERIA) thrives in a very alkaline skin PH and produces the putrid, sour odor. However, the cause of my anal fecal odor's still a mystery.