myelination in connection with the heriditary disease ALD in male chil-
dren and indicate that even high dosages of erucic acid do not seem to
have adverse effects on heart health. As a consequence, dietary veg-
etable oils with up to 20% of pharmacologically pure erucic acid, which
is provided by trierucins of cruciferous plants, are currently offered for
therapeutic applications at several hundred dollars per liter. More re-
cently, trierucins are again controversially discussed with respect to their
neurological effects.
To conclude, genetic engineering of food to functional food will re-
main an enterprise of uncertain economic return as long as regulation
does not provide market exclusivity and the health benefits (or harm-
lessness) of these products have not been proven by real data. Never-
theless, the expanding list of plant compounds with known or claimed
health benefits along with the growing health consciousness of con-
sumers will undoubtedly inspire genetic engineering of functional foods.
FUTURE PROSPECTS
Recent experiences have proven that besides herbicide tolerance, dis-
ease and insect resistances, quality traits are also amenable to genetic
engineering. Table 2.4 gives a summary of genetically engineered qual-
ity parameters in fruit and vegetable. A selection of commercial near-
term products concerning modified quality traits in fruit and vegetables
is given in Table 2.5. In the European Union, transgenic potato and radic-
chio with modified starch characteristics and male sterility (for use in
36 QUALITY AND BREEDING—CULTIVARS, GENETIC ENGINEERING
Alteration of • Fruit softening
- Fruit ripening
- Storage ability
- Total and soluble solids
- Fruit color
- Carotenoid contents
- Sugar profile
- Parthenocarpy
- Starch branching ratio (amylose vs. amylopectin)
- Bruising susceptibility (browning)
Table 2.4. Genetic Engineering of Quality Parameters
in Fruits and Vegetables