Fruits Archana Ghode, Chennai When we say fruits, what comes to our mind is a sweet pulpy food from a plant. Ask a Botanist what a fruit is, and you most probably will get an answer like "a fruit is the ripened seed-containing ovary of any flowering plant". Therefore, botanically speaking, nuts, many vegetables and the ripened pods of roses, poppies and other flowers are actually fruits. A fruit is the final result of plant reproduction. Its development begins after the ovules or egg within the ovary of the flower has been fertilized by pollen. A fertilized ovule becomes a seed. Thus fruits are the containers in which the plant puts its seeds. We can classify fruits into many categories. Some are fleshy with parts we like to eat, some are dry, some are heavy and are designed to be dispersed by falling and rolling away from the parent plant, some have wings or fluffy tails to enable them to be caught by the wind to be dispersed. Fruits and their families Fruits are divided into Fleshy Fruits, and Dry Fruits. Fleshy Fruits can be subdivided again into those formed from a single flower and those formed from a group of flowers. They can have one seed or several seeds inside. Fleshy Fruits formed from a single flower are classified as: Berry (such as totato and gooseberry), Drupe (plum or cherry), Aggregation of Drupes (raspberry), Pome (apple, pear), Hesperidium (most citrus fruit). Fleshy Fruits which grow from a group of flowers are: Sorosis, Synconium, Coenocarpium. These multiple fruits are formed when each flower produces a fruit, with all the fruits maturing into a single mass. Common examples are pineapple and fig. Dry Fruits can be divided into those in which the seeds are contained in a seedpod of some sort which opens to release the seeds (called Dehiscent), and those in which there isn't a seedpod which opens (Indehiscent). Dry Dehiscent Fruits are Follicle (which contain fruit of flowering plants such as delphinium and peony), Legume (the pea and runner bean family), Silique (members of the cabbage family), Capsule (cotton). Some authorities separate these further. Dry Indehiscent Fruits are: Achene (common flowers such as sunflower, dahlia, zinnia), Nut (such as acorn), Samara (maple), and Caryopsis. Caryopsis contains the important members of the grass family such as rice, wheat, rye, oats, barley, and sweet corn. Some people sub-divide some of these further. Knowing the type of fruit a plant has might help you to identify it, and might also help you to know when the seeds are ready to harvest. Some fruits are formed from plant parts other than the ovary and are called accessory fruits. Strawberry is an accessory fruit in which the actual fruits are tiny, hard seeds embedded in a fleshy receptacle. Apples and pears are special kind of accessory fruits called pomes. In a pome the core is the true fruit. The surrounding flesh represents an enlargement of the receptacle. Just as 80% of our body consists of water, similarly fruits also contain 80% of water. If you think about it, it is logical for the human body to consume food that contains as much as water as the body itself. The nutrition that meets this requirement is that from fruits and vegetables. Interestingly all types of fruits are cholesterol-free. If you didn't know it yet, fruit is also the ultimate brain fuel. This is because fruits are also good sources of calcium, potassium, iron and many vitamins. BOX Bananas and bananas : This is perhaps the most common fruit in India. There are many varieties of bananas found in the markets of tropical countries for e.g. Fruitbananas or desertbananas are the normal, yellow bananas, 15-30 cm long. Apple bananas are smaller, 8-10 cm. long, and ripen faster. They are also yellow. The baby-banana (pisang susa) is yellow as well and measures 6-8 cm. It is the sweetest of the banana family; Baking bananas are 30 to 40 cm, large and are green, yellow or red-like. They cannot be eaten raw. They fulfill the role of the potato in other tropical countries. Red bananas are 10-15 cm long. They are mostly grown in South India. The redder a fruit, the more carotene it contains. Red bananas also contain more vitamin C than yellow bananas. India is the world leader in banana production. Carbohydrates Carbohydrates are the principal energy-yielding substance in our diet. They are found in cereals, vegetables, fruits, rice and potatoes. They are manufactured by green plants from atmospheric carbon dioxide and water using the energy of sunlight. The simpler carbohydrates are sugars, such as sucrose (cane or beet sugar) and lactose (milk sugar). Then there are complex carbohydrates like starches, which are compounded sugar units. Proteins Proteins are primary tissue-building substances, which are found in meat, milk, eggs and cereals. The great variety of proteins found in all living things represents different combinations of just about 22 nitrogen-containing amino acids. Many of these amino acids can be manufactured in the body if they are not available in the diet. Eight amino acids, which cannot be made in the body, called "essential" proteins, are found in all body tissues, forming a large part of muscles, as well as bone cartilege and skin. Another group of protein molecules are the so-called antibodies. These circulate in the blood where they fight harmful bacteria, which attack our body. Proteins can also be used as a source of energy. But the energy is not as instant as from intake of carbohydrates. Vitamins Vitamins are organic compounds, which are necessary for life, growth and health of human beings. They are necessary only in very small amounts. The action of vitamins in the body is very complicated, but what they do is help the body to make full and proper use of the food it has digested in the building of new cells and in gaining resistance to diseases. Vitamins can be classified into fat-soluble and water-soluble groups. The fat-soluble vitamins are A, D, E and K. the remaining Vitamins constitute the water-soluble group. Vitamin A promotes growth in animals and also increases resistance to disease. Deficiency of this vitamin causes night blindness and hardening of the cornea in the eye. Vitamin A occurs in fish, carrot, cheese, egg, spinach, butter etc. Vitamin D controls the calcium and phosphorus metabolism and is essential for bone formation. It is produced in the skin by the ultra violet irradiation of sterols. Vitamin D is also found in eggs, butter, cabbage and cream and milk. Vitamin B is essential for our body activity. It is found in peas, beans, cabbage, meat and also found in surplus in a number of fruits, especially in yellow fruits. Lack of vitamin B weakens the nervous system. Vitamin C is widely distributed in fruits like lemons, oranges and in green vegetables and also in potato. This is extremely sensitive to heat. Its deficiency in the diet causes a disease of teeth called scurvy, brittleness of bone and greater susceptibility to disease. Another very interesting thing is that calcium, when taken with orange juice (such as happens in fortified orange juice), is better absorbed than the calcium in milk. A glass of milk (about 225 gms) has 290 mg of calcium, of which 93 mg is absorbed (31%). A glass of fortified orange juice (the same 225 gms) has 350 mg of calcium, of which 130 mg is absorbed (37%). Parts of this article appeared in the May-June, 2002, issue of JM.