Unusual (for me) stool

I am a healthy 42-yr old male; exercise regularly and eat a good diet.  Had a bowel mvmt today that was very odd; part of it was "normal", ie.- medium-dark brown, usual texture, etc. but on one side of it, and then another part on its own (sorry, I know it's a graphic image none of us really enjoy)was much lighter fecal matter, properly formed but somewhat "smoother".  I would describe it as peanut butter texture and the colour of light peanut butter (I know, yuck). I have no pains, cramps, health problems etc. aside from an elevated PSA count last year.  Exam by camera on a probe (can't remember proper term) showed no prostate problems.  One aunt has had a bout of colon cancer which she has been successful in defeating (age 62).  I had a white pasta salad yesterday which is something I have not eaten in a long time.  I am the type who avoids the doctor and I don't overreact to things like this, but it was so unusual I started surfing the net and ended up on this forum.  Can anyone explain or offer any comment?  Many thanks.

[Wilson]

It was probably just a one-time thing. I don't think you have too much to worry about...stool color and consistency can vary greatly, depending on alot of factors.