Malt Extract

MALT EXTRACT

Synonym

Diastase, malt extract.

Biological Source

Malt extract is the extract obtained from the dried barley grains of one or more varieties of Hordeum vulgare Linne, family Poaceae.

Geographical Source

Barley is widely cultivated throughout the world. The major producers are United States, Russia, Canada, India, and Turkey. It is also cultivated in highlands of China and Tibet.

Cultivation, Collection, and Preparation

Barley is one of the oldest cultivated cereals. It is an annual erect stout herb resembling wheat. The crop becomes ready for harvest in about four months after sowing. The grains are threshed out by beating with sticks or trampling by oxen. Dried barley grains are artificially germinated by keeping their heaps wet with water in a warm room. When the caulicle of the grains starts protruding out, the germinated grams are dried. Dry germinated barley or dry malt is subjected to extraction. The malt is infused with water at 60°C. An infusion is concentrated below 60°C under reduced pressure and then dried. Less purified malt extract contains sugars, and amylolytic enzymes. Its further purification affords diastase.

Characteristics

Malt extract contains enzymes, which are most active in neutral solution. The acidic conditions destroy the activity. It converts starch into disaccharide maltose. The enzyme is destroyed by heat. Many heat sterilized malt extracts do not contain diastase. It is completely soluble in cold water, more readily in warm water. The aqueous solution shows flocculant precipitate on standing. Limit for arsenic should not exceed one part per million.

Chemical Constituents

Malt extract contains dextrin, maltose, traces of glucose and about 8% of amylolytic enzyme diastase.

Uses

Malt extract and purified diastase, both are used as amylolytic enzymes and as an aid in digesting starch. They are used as bulk producing laxatives.