The photo to the left shows wort flowing into the boil kettle at the start of sparge. The device at the bottom of the kettle is a homemade filter that keeps hops and other sediment from flowing out in the next stages of brewing. It takes about 45 minutes to complete the sparging process. The final results is approximately seven gallons of wort in the boil kettle. The difference between the water quantity in (10 gallons) and the quantity out (7 gallons) is that which was absorbed by the grain and trapped in the system (heater, tubing, etc.).
I run the burner at low to medium heat during sparge to keep the wort just under boiling point and raise the temperature as the quantity in the boil kettle approaches the final level. Optimally, the wort would start boiling just as the kettle fills but that usually doesn't happen.
Boiling takes at least an hour, sometimes more depending on the recipe. It is during the boil that hops are added to the wort. Hops come in many varieties and in two popular forms, leaf and pellet. I have used both forms but prefer leaf hops over pellets. I buy leaf hops directly from the grower (via the Internet) in one pound lots. I generally keep three or four varieties in stock, mainly Cascade, Saaz, Amarillo, and Northern Brewer. I don't care for overly hopped beer so I normally only use two to three ounces, depending on recipe, per five gallon batch.
The boiled wort must be cooled before yeast is added. There are several ways to accomplish this but I choose to use a plate chiller as shown in the photo to the right. The plate chiller is made up of two closely spaced passages, one for wort and one for cold water. Cooling can be a real problem during the summer in Central Texas where the well water temperature is 70 degrees. I use a pre-chiller to get the cooling water temperature down as low as possible prior to entering the plate chiller. I run the cooling water through a ice bath before it enters the plate chiller and can usually drop the wort temperature to about 70 degrees using this method. Wort flows directly into the fermenter from the plate chiller. I oxygenate the wort and then add the yeast. Fermentation almost always start within 24 hours. The fermenter is moved into the cooler (converted upright freezer) and allowed to ferment for about 10 days. Read more ...