Spritzy 2007 Oregon Pinots

I've heard of three reports of CO2 in the bottles of different 2007 Oregon Pinot Noirs. This causes a light effervescence (bubbles). It's considered a flaw. (Some wines are made to be spritzy--the Italian term for it as a desired trait is 'frizzante.'

Most likely cause is that MLF wasn't complete when the wine was bottled, and MLF continued in the bottle. This is odd, because most commercial wineries will test to ensure MLF is complete, before they bottle.

MLF = malo-lactic fermentation: The natural or induced conversion, by selected strain of bacteria, of malic acid (think green apples) to lactic acid (think butter). Some wines are usually put through MLF (Chardonnay, Pinot Noir), and some are not; this is because MLF is a two-edged sword: It reduces excess acid and makes a wine smoother, but it can also rob a wine of its bouquet and even some of its fruity flavors.