Processed Tomato Score Formulas For The D25A

If you have sharp eyes and read your User's Manual, you may have noticed that two different tomato score formula sets are now available with purchase of the D25 DP-9000 tomato score option. The first is the "older," or legacy, scores, which should be used by operators who have employed these scores in the past or those who wish to compare samples read with historical data or data from other users using these legacy scores. These scores are defined as follows:

1. Tomato Juice = TJS = 29.600 0.88354a - 1.8553b
2. Tomato Paste and Tomato Puree = TPS = -46.383 1.0211a 10.607b - 0.42198b2
3. Tomato Sauce = TSS = -154.39 1.1142a 22.596b - 0.86736b2
4. Tomato Catsup = TCS = -74.937 7.5172a - 0.1278a2 - 0.8051b using C/2°.

The history of these legacy scores is as follows:

In the late 1970s, the United States Department of Agriculture (USDA) conducted a series of tests to develop conversion equations relating tristimulus colorimeter readings to scores defining the visual acceptability of certain tomato products. In a memorandum written by Teri Wolcott, et. al. at the University of California, Davis, these conversion equations were defined for colorimeters and spectrophotometers of several manufacturers, including HunterLab's D25A. These are the legacy equations given above.