An important mineral for its effect on mash and wort pH. It is largely used to harden water when brewing ales and bitters.
Calcium Sulphate causes permanent hardness because it doesn't get removed by boiling. It is believed that sulphate suppresses harshness and astringent flavours which therefore allows brewers to use large amounts of hops without extracting undesirable harshness from other components of the hop. Calcium Sulphate shouldn't be overused though, as it can create a harsh taste and impact on other aspects of the brew.
Use as required depending on water hardness.
CALCIUM SULPHATE FOOD GRADE
Ground Gypsum Superfine White conforms to the specifications listed below when tested in accordance with the methods outlined in the Food Chemicals Codex.
Assay - Minimum of 98.0% Calcium Sulphate calculated on the dried basis.
Arsenic 2.0ppm max
Selenium 30.0ppm max
Heavy metals as lead 5.0ppm max
Fluoride 30.0ppm max
Cadmium 0.5ppm max
Mercury 0.1ppm max
Nitrates 15.0ppm max
The following technical data outlined represents typical figures only.
Colour - Colorimeter measurement
BS Sieves % weight retained
+52 (+300 microns) 0.2% max
+100 (+150 microns) 1.0%
-100+200 (-150 +75 microns) 12%
-200 (-75 microns) 86%
Solubility in water at 20°C 2.1g/litre
Oil Absorption 33ml/100g
Hardness (MOH's scale) 2
Bulk density- loose 825 kg/m'
compacted 1200 kg/m'
Specific Gravity 2.32