Grains are the edible seeds of plants called cereals, which are grass-like plants such as wheat, rice, oats, corn, barley, and others. These seeds are small, hard, and dry fruits (technically called caryopses) harvested for human or animal consumption
. Grains consist of three main parts:
- Bran : The outer hard shell that contains fiber, B vitamins, and minerals.
- Germ : The inner part that contains vitamins, minerals, proteins, oils, and antioxidants.
- Endosperm : The middle layer, rich in carbohydrates and protein
Grains are categorized into two main types:
- Whole grains : Contain all three parts (bran, germ, and endosperm) in their original proportions. Examples include whole-wheat flour, brown rice, oatmeal, bulgur, quinoa, and barley.
- Refined grains : Have been milled to remove the bran and germ, leaving mostly the endosperm. This process improves texture and shelf life but removes fiber, iron, and many B vitamins. Examples include white flour, white rice, and white bread. Some refined grains are enriched with certain vitamins and minerals but lack fiber
Grains are a staple food worldwide, providing about half of the world's food energy. They are found in many common foods such as bread, pasta, breakfast cereals, tortillas, and snacks like popcorn
. Whole grains are linked to numerous health benefits, including reduced risk of heart disease, cancer, and improved digestion, while refined grains have fewer nutrients and fiber
. In summary, grains are seeds from cereal plants that serve as a major food source globally, available in whole and refined forms, with whole grains offering more nutritional benefits.
