Toxic substances in pulses

Deleterious substances of various kinds are present in legume grain eaten by man. Among them are:

1. Trypsin inhibitors
2. Cyanogenic glucosides
3. Goitrogenic factors
4. Hemagglutinins/Haemagglutinins
5. Saponins
6. Alkaloids
7. Tannins
8. flatulent factors
9. Antivitamins
10. Aflatoxin

Contamination with microorganisms could result in the formation of toxins (aflatoxin) which produce adverse effects when ingested.

In most pulses these toxins are destroyed by adequate soaking, removal of the skin and ordinary methods of cooking. In some species removal of the skin and inactivation toxins require prolonged cooking time, pressure cooking or autoclaving, facilities that are available in few households. For any pulse to welcome in a household it should lend itself to ordinary methods of preparation, needing little fuel. Pulses form such an important item of the diet in developing countries that every effort should be made to encourage their consumption by increasing their digestibility.

In the preparation of whole grains, the seeds should be soaked for 24 to 36hoursin a small volume of water, changing the water every 8 to 12 hours. Skins can be removed by rubbing the seeds gently. The grain is then boiled in a little water till it softens. The cooking water should be consumed as it contains water soluble nutrients. When feeding young children, the seeds should be mashed to increase the digestibility. The dhal is more easily cooked than gram. Pulses are the one food that benefits by over boiling.