This is what it says on the Subway.com website about the Tuna.

TUNA - Tuna, Subway light mayonnaise, water, salt. May also contain:
Vegetable broth (may be derived from carrot, soybean), hydrolyzed soy
protein.

LIGHT MAYONNAISE DRESSING Water, soybean oil, modified food starch (derived
from corn), egg yolks, vinegar, contains less than 2% of: salt, eggs,
mustard flour, phosphoric acid, alpha-tocopheryl acetate (Vitamin E) with
potassium sorbate, calcium disodium EDTA as a preservative, artificial
color, oleoresin of paprika, beta carotene, phylloquinone (Vitamin K).

Lori