Water to Grain Ratio Help?

[ricardo]

I'm going to be doing a 22.71 litre (6 US Gallon) batch of a recipe in Mitch Steele's IPA book and the water to grain ratio is stated as 2.8/1 (1.35 qt/lb) for many recipes. My recipe has 7.21 kg or 15.91 lb of grain, Somehow I can't get the sums to work out

2.8/1 gives me 2.8 x 7.21 kg = 20.88 litres
1.35/1 gives me 1.35 x 15.91 lb = 21.47 quarts or 20.31 litres

Now I know it's only half a litre and I'm pretty confident it won't affect anything but this is the first time I have attempted to work out the water to grain ratio and it's made me think I'm doing the math incorrectly

 

[boybrewer]

I think that your sums are not quite correct but close enough . As we know Australia uses a metric system . Pre 1964 we used imperial units which is based on the English weights and measures . The U.S. system measures slightly differently . So 1 U.S. gallon to Imperial gal = .827 , 1 Litre to Imperial gal = .21996 and 1 U.S. gal = 3.7854 Litres . The conversion rate from U.S. lbs to Kilograms is 1: 0.1763698097479 . If you multiply 6 U.S. gallons by 3.7854 = 22.7124 Lt . So 2.8 x 7.21 = 20.188 Lt . 7.21kg to U.S lbs is 1kg x 2.2046 lbs = 7.21 x 2.2046 = 15.895 lbs . Hope this helps .

 

[slash22000]

Pro tip: Google is your friend for all conversions.

https://www.google.com.au/#q=1.35+quart+per+pound+in+litres+per+7.21+kg

= 20.3074986 litres per (7.21 kg)

 

[mb-squared]

Hey ricardo, almost all my recipes come from the states, so I do this conversion all the time. I have found that the following is pretty helpful. First, remember that 1 litre of water equals 1kg in weight. You'll often see American recipes that say 1.25quarts water/pound grain. So let's convert this to weight. First, 1 cup equals 8 oz and 2 cups/16 oz equals 1 pound. How many cups in a quart? Four. So, 1.25 quarts is 5 cups or 40oz; and 40oz divided by 16 (16oz/pound) gets you 2.5 pounds of water -- thus, "1.25quarts/pound" is actually 2.5 pounds of water per pound of grain.

Now converting to metric is easy: simply 2.5 litres of water per kg of grain.

Or you can simply do this: http://lmgtfy.com/?q=1.25+quarts%2Fpound+in+litres%2Fkg

though that will get you slightly different numbers.

Cheers,

matto

 

[ricardo]

I think that your sums are not quite correct but close enough . As we know Australia uses a metric system . Pre 1964 we used imperial units which is based on the English weights and measures . The U.S. system measures slightly differently . So 1 U.S. gallon to Imperial gal = .827 , 1 Litre to Imperial gal = .21996 and 1 U.S. gal = 3.7854 Litres . The conversion rate from U.S. lbs to Kilograms is 1: 0.1763698097479 . If you multiply 6 U.S. gallons by 3.7854 = 22.7124 Lt . So 2.8 x 7.21 = 20.188 Lt . 7.21kg to U.S lbs is 1kg x 2.2046 lbs = 7.21 x 2.2046 = 15.895 lbs . Hope this helps .

Many thanks for the detailed information it's a big help

 

[ricardo]

Hey ricardo, almost all my recipes come from the states, so I do this conversion all the time. I have found that the following is pretty helpful. First, remember that 1 litre of water equals 1kg in weight. You'll often see American recipes that say 1.25quarts water/pound grain. So let's convert this to weight. First, 1 cup equals 8 oz and 2 cups/16 oz equals 1 pound. How many cups in a quart? Four. So, 1.25 quarts is 5 cups or 40oz; and 40oz divided by 16 (16oz/pound) gets you 2.5 pounds of water -- thus, "1.25quarts/pound" is actually 2.5 pounds of water per pound of grain.

Now converting to metric is easy: simply 2.5 litres of water per kg of grain.

Or you can simply do this: http://lmgtfy.com/?q=1.25+quarts%2Fpound+in+litres%2Fkg

though that will get you slightly different numbers.

Cheers,

matto

Thanks Matto appreciate the answer its a big help