Report of the Color Committee

Color as a fundamental quality of edible oils has been determined primarily by visual comparison. The automatic colorimeters introduced recently made it possible to avoid operator variability associated with visual color measurement. The feasibility of using an automatic colorimeter, Colourscan, to measure the color of refined and bleached cottonseed oils was investigated. Good agreement, r2=0.99, between automatic color readings vs. visual color measurement by using the Lovibond‐AOCS Color Scale was obtained. Near‐linear correlation of light paths from 133.4 to 2.5 mm permits dark oil to be assessed with the automatic colorimeter.

Comparison of visual and automated colorimeter for refined and bleached cottonseed oils

Wan

Pakarinen

1995

Application of spectrophotometric methods to the determination of glycerine color

Miner¹,

Weil²

1949

SummaryA method has been developed by which spectrophotometrically measured glycerine color can be expressed in terms of Lovibond units. The yellow and red color values are determined, by means of two statistically derived linear relationships, from optical density measurements at 440 mμ and 520 mμ, respectively. The conversion from spectrophotometric data to Lovibond color units may be done graphically and the results are at least as reliable as the results of repeated visual measurements.

Determination of oil color by image analysis

Sun¹,

Zhao²,

Zhou³

2001

An image analysis method was developed to determine oil color based on Lovibond-red according to Chinese standard GB5528-85. For one hue, one feature of image analysis, a negative correlation with the red reading of the Lovibond tintometer (r > 0.995) was found. Mathematical models were designed to measure oil color based on image analysis. Fortynine oil samples including peanut oil, soybean oil, fragrant sesame oil, rapeseed oil and cottonseed oil were evaluated to assess the performance of the image analysis models. Good agreement, r 2 = 0.999, between image analysis values and visual color measurement by using the Lovibond Color Scale was obtained.Paper no. J9621 in JAOCS 78, 749-752 (July 2001).