Page 114 - Feed Lab

Suguna Management System Ver 1.0 / SOP / FQL / P2 - 28 Page 1 of 1

28. Estimation of Colour of Oil

sample, initially by using the color racks in the ratio
SCOPE
of 10 yellow to 1 red. Correct until an accurate color
Applicable to testing of all vegetable fats and oils.
match is obtained without unnecessarily main-
tainting the ratio of 10 yellow to 1 red & using the
OBJECTIVE
minimum number of blue or Neutral units to obtain
The method determines color by matching the color of the match but not more than 9.0 blue and 3.0
the light transmitted through a specified depth of liquid neutral.
or oil to the color of the light originating from the same
sour the transmitted through glass color standards FThe chemist may rest the eyes after each 30-sec
period of matching.
APPARATUS
FRecord the size of cell used and the red yellow, blue
FLovibond Universal Tintometer or neutral readings forming the color match.

FGlass Cells : Made of optical glass with optical FAcceptance color reading difference:
path length as following:
1. 6.4 mm (1/4") Reading Acceptable Differences

2. 25.4 mm (1") Up to 0.9 red 0.2 Red
From 1.0 red to 2.9 red 0.4 Red
3. 133.4 mm (5¼" Cell)
From 3.0 red to 4.0 red 0.5 Red
PROCEDURE
From 4.1 red to 12 red 1.0 Red
FIt is essential that the determination is carried out in
subdued ambient light i.e. not facing a window or
direct sunlight.

FPour the prepared sample into a clean & dry cell of CALCULATION
required length to give color readings within the The number of red, yellow and blue or neutral readings
range given in Apparatus. needed to obtain the match and the formula used Y+

FPlace the cell containing the sample in the 5R for the length of cell used ¼", 1" or 5¼" For crude oil
Tintometer. Immediately determine the color of the bleached oil and refined oil respectively.

Prepared by : Approved by :
102 Director - Technical