Hi,
I am new to this forum and new to all grain brewing. I have had two brew days so far and both times I have missed my target OG, which was 1.051 for both of the recipes I used. First time the mash temperature was all over the place, too hot and too cold at different times and I achieved an actual OG of 1.038. Second time I managed too keep the temperature between 64.7 - 65.5 Celsius for 90 minutes but the actual OG was still only 1.042.
I am mashing in a 3 gallon stock pot. Following suggestions from a small batch recipe that I found I have been putting the pot in a pre-heated oven to maintain the temperature.
I am hoping that someone might be able to suggest a way that I can get closer to my target OG.
Hey Uncruliar,
I definitely understand the frustration of missing your Target OG as I did by quite a bit my first few batches as well. There are a number of factors that could have resulted in the lower than expected OG that you recorded. Ultimately, however, hitting your target OG is going to come down to consistency in your brewing process. You will need to take good notes, find a procedure that works for you, and stick to it (usually... its homebrewing... experimentation is a lot of fun). Since I have done this, I have consistently been able to hit my OG within a couple points. Also, I am unsure where you found this recipe, but you need to adapt each recipe you brew to your own system using batch sizes and efficiency (unfortunately, some recipes you find online do not provide the necessary information to do this, but many do). You could have done everything else perfectly, but if the recipe is not adjusted for your system, you run the risk of producing a beer far from what you had planned. It may take a couple brews to determine your efficiency, so don't worry about missing your OG the first time. Just take good notes and adjust for next time.
That said, the following should provide a decent starting point for more consistently hitting your target OG... I would first check that the volumes you are using for your calculations are right for your system and process. If you are doing an 60 minute boil, boil a measured amount of water for 60 minutes to determine your boil off rate. This will tell you how much wort you need to have in the boil pot before you even start the boil (your preboil volume), and then you know you will have the right volume at the end of the boil. This will help ensure you are hitting your volume. If you consistently are hitting the right volume, you can rely on the value you obtain for your efficiency. If you know your volumes and your efficiency, you can hit your target OG with a much higher degree of regularity.
Two other factors to keep in mind once you have your process down (there are others... i.e. mash pH) that immediately pop into mind to more consistently hit your OG are:
1. During your mash, make sure your water : grain ratio is consistent from brew to brew. I (usually) use 1.75 quarts for every 1lb grain in the recipe for my mash and then sparge the rest to obtain my desired preboil volume.
2. Ensure your grains are sufficiently and consistently crushed. A fine grind will result in a different mash efficiency than a course grind.
For your average brewday, hopefully this will provide a good starting point for you to more consistently hit your target OG. As I said, it will take a couple of batches to determine your efficiency and to gain the familiarity with your system that it takes to consistently hit your target OG, but once you do, it's a lot of fun! As you get more into the hobby and experiment more, you will find you need to make changes to that process (either just because you want to try something new, cause your using different/unique ingredients, because its a super high gravity beer, or any one of a hundred other reasons), but thats part of the fun of homebrewing, you have free reign. That said, put as much or as little of what I have to say to practice, just don't expect to consistently hit your OG till you know your system and have fun with it!
Cheers!