I have noticed something strange about this yeast and wonder if it possibly contains two different strains. The first time I used it, I made a starter and then cooled it so I could decant. A lot of the yeast dropped out quickly but even after 12 hours a lot was still in solution. Since I had to pitch soon the liquid got dumped.
I recently used this yeast again and again made a starter. Noticed same thing as before, most flocculated fairly quickly but some stayed in solution. Decanted as before and brewed. I kept the beer in the primary for three weeks while I was out of town, then racked it off. Washed the yeast in the cake to remove the trub and then put it in the fridge. Again, a lot of yeast dropped out in just a few hours but some stayed in solution. Since I was not going to used it for a week I kept it in the fridge this time.
After 4 days in the fridge, a good portion of the yeast that didn't want to settle finally did. It was obviously lighter than the yeast that fell out quickly but did have the same beige yeast color.
I have read that Duvel uses two different stains in their primary fermentation and wonder if Wyeast is perhaps duplicating this with two different strains in their Moortgat strain? Perhaps I should just contact them, but was curious if anyone else has noticed this?