Iodophor and cross contamination

I make beer as well as wine. Both are made in my basement brewery-wine cellar with a lot of the same equipment. Regardless of the beverage all equipment is washed immediately after it's use. This goes for bottles and kegs also. For wine I let the equipment and bottles drip dry and take no further action. For beer I clean as above but before I use carboys, pumps, tubing or bottles I treat with Iodophor. I add some citric acid to the Iodophor solution to lower the pH. I understand Iodophor is more effective in an acid pH. I keep some pre boiled water handy to run through my pumps and tubing after Iodophor treatment because some solution pools in those items. Carboys are drained and inverted, then covered with aluminum foil until they are filled. Bottles are emptied, allowed to drip and are immediately filled with primed beer. I don't let the Iodophor dry in containers. In the past I noticed a film that formed on the inside of beer bottles when they were treated with Iodophor and allowed to dry before filling.

Since I make beer and wine in the same place, and since beer and wine yeasts are floating around in the air, I have to be especially careful with beer wort. I've had some batches of beer ferment much lower in final gravity than I expected and think they may have been contaminated with wine yeast. So, for me I'm pretty lax when sanitizing for wine but over cautious when sanitizing for beer.

Bill Frazier Olathe, Kansas USA