Manufacturers also can use dyes made from plant, animal or mineral sources, such
as beets,
caramel color or grape color extract, but the petroleum - based colors are cheaper and can be more consistent.
Manufactured pet foods can contain umectants like sugar / sucrose, corn syrup, sorbitol and molasses; antimicrobial preservatives like propionic, sorbic and phosphoric acids, sodium nitrite, sodium and calcium propionate and potassium sorbate; natural coloring agents like iron oxide and
caramel, and synthetic coloring agents like coal - tar derived azo - dyes such
as Yellow 5, Red 40, Yellow 6, and Blue 2; emulsifying agents used
as stabilizers and thickeners, such
as seaweed, seed, and microbial gums, gums from trees, and chemically modified plant cellulose like citrus pectin, xanthan and guar gum, and carrageenan; flavor and palatability enhances include «natural» flavors, «animal digest», and even MSG (monosodium glutamate); natural fiber like
beet pulp, and miscellaneous additives like polyphosphates that help retain natural moisture, condition and texture of manufactured pet foods.