This
section analyses all the water in the brewery starting from the source of water
supply which is the borehole, to product water, soft water, boiler water,
alcohol water, cooling water etc. This section checks for certain ion content
of the waters to ensure that it doesn’t react with the product when brewing.
The waters are checked for the following:
1.
PH TEST
This measures the level of acid and
alkaline in the water.
Procedure:
1.
Rinse the PH
electrode with the sample twice
2.
Place the PH
electrode in the sample and allow beating
3.
When stop
beating, read off the result.
1.
FREE
CHLORINE
Apparatus:
spectrophotometer, DPD chlorine reagent.
Procedure:
1.
On the
spectrophotometer, press 80 and ENTER
2.
Dial to 430.
3.
Insert the cell
rinser into sample compartment.
4.
Fill 10mls cell
with sample (i.e. blank). Place it into the cell holder and close the light
shield. Then press “ZERO”.
5.
Fill another 10
ml with sample and add one sachet of DPD free chlorine powder and shake for 20
seconds.
6.
Place the sample
into cell holder, close the light shield and press ”READ”
Then take the final reading
1.
PHENOLPHTHALIEN
ALKALINITY
Procedure:
1. Measure 100mls of sample and pour into a flask using a
measuring cylinder.
2. Add 3-5 drops of phenolphthalein and shake.
3. If the colour remains, then the titre value is 0.
4. If the colour changes to rose pink, then titrate to
get titer value with 0.1N HCl until it turns colouless. Then read off.
4. METHYL ORANGE ALKALINITY
Procedure:
1.
Measure 100mis of
sample and pour in a flask.
2.
Add 5 drops of
methyl orange.
3.
NB. If changes to
orange or yellow colour , titrate with
0.1N HCl till it changes to rose pink. Then take your titre value.
5. TOTAL HARDNESS
Procedure:
1. Measure 100mls of the sample into a conical flask
2. Add the titre value of 0.1N HCl acid of the methyl
alkalinity
3. Add 4mls of ammonium buffer into the flask
4. Add little quantity of Eucrom black into the flask
(the colour changes to purple)
5. titrate with 0.2N EDTA(the colour changes from purple
to blue)
6. Then read off from the burette. (Multiply the titre
value by 1.12 to convert it to °G)
6.
CALCIUM HARDNESS
Procedure:
1.
Measure 100mls of
the sample into the conical flask
2.
Add the titre
value of 0.1N HCL acid of methyl alkalinity
3.
Add 1 ml of KOH
into the flask
4.
Add little
quantity of muroxide(the changes to pink)
5.
titrate with 0.2N
EDTA(the colour changes from pink to purple)
6.
Read off from the
burrette and multiply by 1.12
7.
MAGNESIUM HARDNESS
The difference between the total
hardness and calcium hardness gives the value for magnesium hardness.