Two spec sheets arrive for the same 31 percent hot break paste. One lists color as 45 to 50 points, the other lists a minimum Hunter a/b ratio, and both suppliers describe their product as a bright, deep red. Neither number can be compared with the other until you know how each was measured. A tomato paste color specification looks like a single line on a spec sheet, but it carries a grading system, a dilution step, and an instrument choice inside it.
Color is also a quality attribute your own customer judges without a lab. A finished sauce that looks off-color on the shelf can lose a sale before anyone tastes it.
One Source Food Solutions supplies hot break and cold break tomato paste from California processors. If you are writing or revisiting a tomato paste color specification, we can help you decide which measurement belongs on it.
Why Does Color Carry So Much Weight in Tomato Paste Quality?
Color is half of the grade. Under the USDA grade standards for canned tomato paste, color is worth 50 of the 100 points that determine a grade, and defects make up the other 50. Grade A requires good color, defined as a bright, typical red, with a color score of 45 to 50 points. Paste that scores 40 to 44 for color is defined as a typical red that may be slightly dull or slightly brownish, and a limiting rule keeps it from grading above U.S. Grade C no matter how well it scores on defects. Color score is not the only visual check. Dark specks and scale-like particles are scored as defects, so a paste with a strong red can still be held to Grade C by visible blemishes.
FDA sets a separate minimum. The standard of quality for tomato concentrates in 21 CFR 155.191 compares the paste, diluted to 8.1 percent tomato soluble solids, against a composite color produced by spinning Munsell color discs. A concentrate that falls short must carry a substandard-quality statement on its label, and the regulation allows that statement to read “Below Standard in Quality: Poor color.”
Where Does Processed Tomato Color Come From?
Processed tomato color comes mostly from lycopene, the pigment principally responsible for the deep red of ripe tomatoes and tomato products. How much of it reaches a paste depends first on the fruit. Under California’s processing tomato inspection program, a delivered load can be rejected if comminuted samples fail the minimum color standard (the program suggests a maximum Hunter hue angle reading of 25) or if more than 4 percent of the load by weight is green fruit. The program also records gray wall, a dark brown or black discoloration of the vascular bundles in the tomato wall, on the inspection certificate for information rather than as a rejection criterion.
Lycopene levels also differ by variety, and growing-season weather shifts pigment development from year to year. That seasonal side is covered in our look at what causes variability in tomato products from season to season.
How Does Processing Change Tomato Paste Color?
Processing can protect color or erode it, beginning with break temperature. Our FAQ lists cold break at 60 to 70 degrees Celsius and hot break at 90 to 98.8 degrees Celsius. Research published through the National Library of Medicine explains what that difference means for color: cold break paste keeps good color and flavor because of its lower processing temperature, which suits it to diluted juices and vegetable blends where a natural red is the goal, while hot break paste delivers the viscosity that ketchup and pizza sauce depend on.
Color can keep changing after the paste is sealed. Aseptic paste is shelf-stable at ambient temperature, but ambient covers a wide range. In a study of aseptic cold break paste held for 12 months, markers of browning rose significantly at 33 degrees Celsius (about 91 degrees Fahrenheit), while no significant increase appeared at 21 degrees Celsius (about 70 degrees Fahrenheit). Because browning moves paste toward the Grade C description, it is worth asking about a lot’s pack date and warehouse history.
How Is Color Reported on a Specification Sheet?
A tomato paste color specification can take one of three forms. The first is a USDA color score in points: our hot break and cold break spec sheets list a Grade A color score measured on a Hunter Lab colorimeter, and the USDA standard accepts readings from approved electronic meters as long as they convert to score points through an approved formula. The second is the Hunter a/b ratio, a widely used tomato color ratio in which “a” runs from green to red, “b” runs from blue to yellow, and a higher ratio indicates a redder product. Because redness tracks lycopene content, some colorimeter makers offer firmware that converts a/b readings into an estimated lycopene index.
The third is a comparison against a physical reference. Under the USDA paste standard, Grade A color must look at least as red as USDA Color Standard A2 and Grade C color must match or exceed the redness of Standard C2, while our bulk ketchup specification references the Tomato Catsup Standard instead. Since June 2026, USDA’s tomato grade standards reference these physical color standards rather than the spinning Munsell discs the FDA regulation still describes. Licensed suppliers sell them, so a QA lab can keep the same physical references inspectors grade against.
When Do Small Color Differences Affect a Finished Product?
Small color differences matter most when the finished product is graded on color itself. USDA’s grade standards for tomato sauce award 21 to 25 points for good color at Grade A, and the ketchup standard gives good color the same range. A paste sitting at the low edge of Grade A leaves less margin for color lost during cooking and holding.
The effect fades as other ingredients take over more of the visible color. In a cream-based soup or a heavily spiced chili, a few points of variation may go unnoticed. In a clear marinara or a tomato juice, the tomato is the color, and the same variation may be obvious. Lot-to-lot consistency may matter as much as the absolute score, because a product line that draws on several lots for one SKU can show visible differences between production dates even when every lot meets specification.
How Should You Write a Tomato Paste Color Specification?
A workable tomato paste color specification names the measurement system, the dilution, and the acceptable range together. Dilution belongs in that line because paste color is read on diluted product, and the USDA and FDA methods use different dilution levels. “Grade A color” tells a supplier which grade line to meet, while “USDA color score of 45 to 50 points at 8.5 percent tomato soluble solids, measured on an approved colorimeter” tells them exactly how your team will check it. If your QA lab reports a/b ratio instead, state the ratio range and the dilution your lab uses, so the supplier can measure the same way before shipping.
Two habits keep a tomato paste color specification useful after it is written. Ask for color on every lot’s certificate rather than on a single qualifying sample. For color-critical products, also bench-test the lot you will receive in your finished formula, because the score on the certificate describes the paste, not the product you sell.
Connect With One Source Food Solutions
Our R&D support includes Tomato School, an orientation and training program built around product specifications for tomatoes and tomato products in every style, package, and format available in the market. Once an order ships, we email the Certificate of Analysis to your team within hours, so color can be checked against your tomato paste color specification before the lot reaches your line.
To request R&D samples for color testing, call One Source Food Solutions at (360) 887-9430 or reach out through our contact page.