of the least expensive cooking processes, it is limited to whole gains and products with uniform piece sizes. Roasting dries grains and destroys much of the surface microflora, thus increasing the shelf life if the product is protected from moisture and insects.


Soaked whole grams can be sprouted prior to cooking to increase vitamin levels, reduce the molecular weight of the carbohydrates that are present, and increase the availability of essential amino acids and relative nutritional value of the food (Wang and Fields, 1979). The amylases, released during germination hydrolyze starch to shorter-chain carbohydrates and sugars, facilitating digestibility and reducing viscosity at elevated concentrations to increase the caloric density of foods (Mosha and Svanberg, 1983). Once sprouted, grains have to be dried if they are to remain stable. Heating during or following drying increases flavor and acceptability.


Milling, a spectrum of processes, cleans and separates the components of grains (germ, bran, endosperm) and reduces their size. Mining has the beneficial effect of lowering fiber and bulk but it is at the expense of a lowered vitamin and mineral content in the remaining flour.

Cleaning steps associated with milling can remove insect and microbiological contamination of raw materials. The mined product, however, is more susceptible to insect damage if it is not protected in packaging that is puncture resistant and resealable Bacteriological growth is not a concern in mined products as long as they have less than a 15 percent moisture content.

Milling lowers the phytates present in the bran of many cereal grams and legumes that interfere with the absorption of starch, calcium, minerals, and trace elements. Tannins, which are present in the seed coats of many pigmented cereals, can inhibit the digestion of protein and starch if they are not removed during milling. Simple mills can replace the labor-intensive and time-consuming pounding, grinding, and handwinnowing techniques that are commonly used. Mills consisting of stone or metal grinding parts and blowers can be manufactured locally.

Milling by itself does not produce a supplementary food. Instead, mined ingredients are more suitable and convenient for formulating supplemental foods. Milled flours cooked with water form thick gruels with low nutrient

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