Extraction rate trouble. I have always had lower than expected S.G. from my mash-washes...Help?

Question

I have decided I need to be more frugal and get every drop.

Answer 1

I can't help with ths advanced stuff. But I learned some things for the future. I have a question on a bock beer can you help me?

Answer 2

Let me add to the above by saying pH and a static grain bed will influence extraction rates as well.

The temperature will need to be maintained for end mash of enzyme activity and better release of wort from the grain bed. So I agree with the temps. given above.

The length of time is vital to good extraction as well. In fact the temp. and time of sparge are critical to good extraction. Keep the sparge water hot and the water-wort flow low to maintain at least 30 minutes for the sparge.

The grist and compaction are directly related. The filter bed formed and its ability to maintain itself is related to a stratified husk size. You want large and small pieces of husk to form a proper bed. So make sure your malt has been milled properly.

The pH influences both the conversion or diastatic activity and extraction of wort. For infusion mashes proper diastatic activity is achieved with a pH range of 5.2-5.8. Fortunately, this is usually naturally achieved with good malts. Unless your water is very hard or very soft no pH adjustments are needed.

One factor that has a great impact on wort extraction during sparging is a static grain bed. This too relates to bed compaction. It also has to do with hydrodynamic flow of the sparge water and wort. When the bed rises and drops due to flow of the kettle bound wort, the channeling of water in the bed changes. It is the channeling (streams) of sparge water that gives increased wort extraction rates. As the bed rises and drops it causes the bed to compact as well. This too decreases extraction, as the water is unable to tunnel through the bed. The flow over the grains disperse and throughly "wash" grains. So mark the inside of your mash-lauter vessel at the bed level and try to maintain this as closely as possible.

A static grain bed (immobile) along with the temp. and time of sparge will greatly improve your wort extraction. You should see more stable S.G. when you bring these things into line.

Answer 3

It could be several things. Temperature is often a concern. Many people are so concerned with tannic extraction they use low sparge temperatures resulting in a low sp. gr. I use sparge temperatures of no less than 170F and often as much as 176F. I have no problems with astringency.

Another problem is to fast of a sparge run. Even in a small mash it takes time to flush the wort from the grain bed. In a 7-gal batch I usually sparge for 30-40 minutes. Not that my sp .gr. is always perfect but I am close most times.

Answer 4

I can list a few things to focus on for your mash & sparge.

1. Temperature

2. Time

3. Grist size-milling

The temperature in both your mash and sparge need to be maintained. In the mash keep the temperature constant for conversion and the sparge for extraction. The sparge needs to be hot enough in an infusion mash to stop enzyme activity and liquefy the sugars or separate them for the grain. TIME to needs to be regulated to meet specified specific gravity both in the mash and sparge. Just keep it at least 168F but higher is better.

The Grist needs to be well crushed to expose the flour but not to destroy the husks. You want a good filter bed to from the grain husks. And so they need to be broken into small, medium, and large chunks. From that a good filter is naturally formed. Faster runs often occurs because where the husks have been milled to large or the sparge liquor is too fast. I am not saying you get a stuck mach but a slowed one. Were the grain is pressed together from the flow of wort. So sparge slowly to avoid that.