plant’s tissue is damaged by chewing, the
cyanogens are mixed with the plant enzyme
that breaks them apart and releases hydrogen
cyanide (HCN). Cyanogen-rich foods,
including manioc, bamboo shoots, and
tropical varieties of lima beans, are made safe
for consumption by open boiling, leaching in
water, and fermentation. The seeds of citrus,
stone, and pome fruits generate cyanide, and
stone-fruit seeds are prized because their
cyanogens also produce benzaldehyde, the
characteristic odor of almond extract (p. 506).
Hydrazines Hydrazines are nitrogen-
containing substances that are found in
relatively large amounts (500 parts per
million) in the common white mushroom and
other mushroom varieties, and that persist
after cooking. Mushroom hydrazines cause
liver damage and cancer when fed to
laboratory mice, but have no effect in rats. It’s
not yet clear whether they pose a significant