Hanna Instruments HI 83749 - Manual (Page 20)

20
DETERMINATION OF BENTONITE REQUIREMENT
SAMPLE PREPARATION
• Fill 4 HANNA vials with 25 mL of unfiltered wine
sample.
• Prepare a bentonite suspension of 2.5%.
Note: use always a bentonite suspension with
the same wetting degree as the suspension that
is used in production.
• Use the 1 mL syringe to add 0.25 mL of
bentonite suspension to the vial #1; then add
0.50 mL to #2, 0.75 mL to #3 and 1 mL to
#4.
Note: in order to measure the exact volume of
bentonite suspension with the syringe, follow
the instructions on page 11.
• Close the glass vials tightly with their caps and
mix thoroughly.
#1
#2
#3
#4
#1 #2 #3 #4
0.25
mL 0.50
mL 0.75
mL 1 mL
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• Wait for 15 minutes to allow suspended matter
to settle.
• Fold a filter disc twice as shown in the figure.
• Separate one side from the other three to form
a cone. Insert the folded filter disc in the funnel.
• Decant off clear liquid and filter the treated wine
from vial #1 into cuvet #1 to collect 10 mL
of filtered sample. Place the cap #1 and wipe
the cuvet thoroughly with a lint-free cloth (see
General Tips for an accurate measurements,
page 10).
• Prepare fresh filters and repeat the filtration for
all treated wine samples (#2, #3,#4).
#1 #2 #3 #4
READING PROCEDURE
• Turn the instrument ON by pressing ON/OFF.
When the LCD displays “----”, the instrument
is ready.
• Select the AVG mode by pressing the AVG
key. The AVG icon will appear on the display.
#1
#1