226 3 Lipids
Fig. 3.41.Fungal degradation of triacylglycerols to methyl ketones (according toKinsellaandHwang, 1976)
Table 3.47.Sensory properties of methyl ketones
Compound Odor Odor threshold
description (ppb; in water)
2-Pentanone Fruity,
like bananas 2300
2-Hexanone 930
2-Heptanone Fragrant,
herbaceous 650
2-Octanone Flowery,
refreshing 190
2-Nonanone Flowery, fatty 190
a soap solution (alkali salts of fatty acids) by
extraction with an organic solvent.
The unsaponifiable matter contains hydrocar-
bons, steroids, tocopherols and carotenoids. In
addition, contaminants or fat or oil additives,
Table 3.48.Content of unsaponifiables in various fats
and oils
Fat/oil Unsaponi- Fat/oil Unsaponi-
fiable fiable
(weight-%) (weight-%)Soya 0 .6–1.2Shea 3.6–10. 0
Sunflower 0.3–1.2Lard 0.1–0. 2
Cocoa 0.2–0.3 Shark 15–17
Peanut 0.2–4. 4 (refined)
Olive 0 .4–1.1 Herring 0 .7–1. 0
Palm 0 .3–0. 9 (refined)
Rapeseed 0.7–1. 1such as mineral oil, plasticizers or pesticide
residues, can be found.
Each class of compounds in the unsaponifiable
matter is represented by a number of components,