Seven samples of feed- or pet food-grade
fats (feed- and pet food-grade poultry greases, restaurant
grease, white grease, animal/vegetable oil blend, palm
oil, yellow grease) and one food-grade edible fat (soybean
oil) were evaluated for quality and fatty acid composition.
Active oxygen method (AOM) stability at 20 h ranged
from 2 to 370 meq/kg; iodine value from 78 to 130 g/
100 g; total moisture, insolubles, and unsaponifiables
from 0.46 to 3.33%; initial peroxide values from 0.2 to
18.4 meq/kg; and free fatty acids from 0.08 to 21.0%. The
ME of the fats ranged from 7.1 to 12.7 kcal/g and was
positively correlated with AOM stability and iodine