Rice is a part of grain (rice) which has been separated from the husk. Chaff (Javanese straw) is anatomically called ‘palea’ (part covered) and ‘lemma’ (part that covers).
At one stage of processing rice yields, the grain is crushed with mortar or ground so that the outside (grain skin) is detached from its contents. This part of the contents, which are white, reddish, purple, or even black, is called rice.
Rice generally grows as an annual plant. Rice plants can grow up to as high as 1 – 1.8 m. The leaves are long and slender with a length of 50-100 cm and a width of 2 – 2.5 cm. Edible rice is 5 – 12 mm long and 2-3 mm thick.
Anatomy of rice
Rice itself is biologically a part of rice seeds consisting of aleuron, the outer layer which often participate wasted in the process of separating the skin, endosperm, where most of the starch and rice protein is located, and the embryo, which is a prospective new plant (in rice can not grow again, except with the help of tissue culture techniques). In everyday language, embryos are referred to as rice eyes.
Rice content
As with other cereals, the bulk of rice is dominated by starch (about 80-85%). Rice also contains protein, vitamins (especially in the aleuron), minerals, and water.
Rice starch is composed of two carbohydrate polymers:
– amylose, starch with unbranched structure
– amylopectin, a branched structure and tends to be sticky
Comparison of the composition of these two classes of starch greatly determines the color (transparent or not) and the texture of rice (sticky, soft, hard, or pera). Sticky rice is almost completely dominated by amylopectin so it is very sticky, while pera rice has an amylose content exceeding 20% which makes the rice grains scattered (not attached) and hard.
Kind and color of rice
Different colors of rice are genetically regulated, due to differences in genes that regulate aleurone color, endospermia color, and starch composition in endospermia.
White “normal” rice is rather transparent because it only has a small amount of aleuron, and the amylose content is generally around 20%. This rice dominates the rice market.
Brown rice, due to its aleuron contains a gene that produces anthocyanin which is a source of red or purple.
Black rice, very rare, is due to aleurons and endospermia producing high intensity anthocyanins so that they are dark purple approaching black.
Sticky rice (or sticky rice), white, not transparent, all or almost all of its starch is amylopectin.
Black sticky rice, is a sticky version of black rice.
Some types of rice emit a fragrant aroma when cooked (for example ‘Cianjur Pandanwangi’ or ‘Rajalele’). The smell is caused by the rice releasing aromatic compounds which give a fragrance effect. This trait is genetically regulated and is the object of genetic engineering in rice.
Food aspects
Rice is mainly used to be processed into rice, the most important staple food for world citizens. Rice is also used as a material for making various kinds of snacks and cakes, mainly from sticky rice, including for tapai. In addition, rice is an important component for kencur rice and param. Popular drinks from processed rice are wine and starch water.
In the food industry, rice processed into rice flour. Sosohan rice (aleuron layer), which has a high nutritional content, is processed into rice bran. The embryo is also processed into food supplements as rice flour.
For the purposes of diet, rice is used as one of gluten-free food sources in the form of popcorn.
Among the various types of rice in Indonesia, red or red rice is believed to have medicinal properties. The red rice which has been known since 2,800 BC, by the doctors at that time was believed to have medical values that could restore a sense of calm and peace. Although, compared to white rice, the carbohydrate content of brown rice is lower (78.9 gr: 75.7 gr), but the results of Nio’s analysis (1992) show the value of energy produced by brown rice is actually above white rice (349 cal: 353 cal ). Besides being more protein rich (6.8 gr: 8.2 gr), this may be due to its higher thiamine content (0.12 mg: 0.31 mg).
Thiamine deficiency can interfere with the nervous system and heart, in severe conditions called beriberi, with early symptoms of decreased appetite, indigestion, constipation, fatigue, tingling, palpitations, and reduced reflexes.
Other nutritional elements found in brown rice are phosphorus (243 mg per 100 grams of material) and selenium. Selenium is a trace element (trace element) which is an essential part of the enzyme glutathione peroxidase. This enzyme acts as a catalyst in the breakdown of peroxides into non-toxic bonds. Peroxides can be turned into free radicals that are able to knock
