THE RICE  CHAFF




HISTORY

Rice is one of the best-known cereals worldwide, first discovered about 5000 years ago. In fact, it is though that it was discovered before wheat. It is also the most widely used cereal in the world, and is a staple food for about one-third of the world’s population.
The plant originally comes from the south-east Asia regions and began to be known in the western world in the 1st century B.C.
In the Greek-Roman worlds, rice was considered to be an extremely expensive exotic spice, a reputation that continued to the Middle Ages.
In Italy rice began to be cultivated in the area around Milan and Vercelli at the end of the 15th century. This is an area that still produces products of excellence today.
Rice is now grown in Egypt, the United States, Brazil and Australia, as well as in Eastern Asia countries.

THE PLANT AND CULTIVATION

Rice is a tropical plant that needs suitable temperature and humidity to grow. It is a plant that loves water, needs a hot-humid climate and grows to about one metre in height. When the grain is mature, the rice plant looks similar to the oats plant.
The young plant develops from spring until late summer, with a vegetative cycle of between 150 and 180 days.
A temperature of around 30° is needed for the plant to flower and it has been calculated that about 3000 to 10,000 litres of water are needed to obtain one kilogram of rice.
There are basically four cultivation phases: preparation of soil, immersion of plots of land and sowing, elimination of weeds; harvesting.
These operations, which were once entrusted to thousands of workers are now completely mechanised in Italy. The change came about in the rice fields starting from the end of the 1950s when the machines, fertilisers and the selective formulas for the removal of weeds reached a sufficient stage of development.
One of the most interesting moments in rice cultivation is surely the spring flooding of the land, which is carried out using a complex channel system. The rice field is turned into a never-ending artificial lake that changes from silver to pastel green just a few weeks, due to the young plants that begin to emerge from the water. Harvesting is just as interesting. The harvesting machines, that cut the rice quickly and separate from the straw, manage to concentrate a large quantity of work over large surface areas in a short period of time.
When the cereal is taken from the fields to the companies on trailers, it has a humidity factor of between 20% and 30%. The unprocessed rice, or paddy, as it is known, is then placed in the drying plants so that the humidity is reduced to 14-15° and does not cause the plant to deteriorate. Freshly harvested rice grains are covered by a husk several layers thick that is brown or yellow in colour, which contains several substances.
Underneath the protective layers, or integuments, that grower thinner from the outside inwards there is the caryopsis. Each grain also carries an embryo, inside a small sac, that is called the spermoderm and which is vital for the continuation of the species. The grain is made up of proteins and of tiny, spiky starch granules in the innermost part, that are joined together in bunches.

VARIETIES OF RICE

Rice is classified into short-grain, medium-grain, long-grain and extra-long-grain types. The attribution of category to the types of rice available depends on the length and size of the grain, its appearance, its behaviour during cooking. The short-grain rice varieties are shorter than 5.4 mm; medium-grain rice types are between 5.4 and 6.4 mm; long-grain rice varieties are more than 6.4 mm.
Some needle-shaped varieties grown in the Far East are even longer.

PROCESSING

Transforming rough rice into edible rice is a fully mechanical process; therefore no adulteration processes can be introduced to damage it.
The principle still used today for rice processing is the one known as “husking”.
The rough rice was once placed in mortars, also known as huskers. A pestle with a metal tip was used to crush the grain and the outer layers containing fats and albumin were removed in this way. The embryo or bud, rich in oil, was also removed in this way. As this operation inevitably crushed a certain amount of the actual grains too, it was also necessary to remove them, together with the other impurities, using separators known as oscillating sieves that were hung from the ceilings on ropes.
The modern automated company structure follows a strict processing pattern. The rice, cleaned of any foreign matter and also of its outer layer using a hulling machine, or chafing machine, is passed into an initial whitening machine: here the pericarp and the embryo disappear. At this point a semi-rough paddy, or hulled rice is obtained, rich in vegetable fibres and fat parts; it is therefore recommended for special diets.
A second whitening machine produces semi-processed rice or merchant rice, while processed rice is obtained using a third whitening machine. The state of processing increases even more if the rice is passed through a fourth whitening machine.

NUTRITIONAL PROPERTIES

Each kilogram of processed paddy produces 600 grams of edible rice. The processing also gives of by-products used for preparing animal feed, or in the cosmetic and refractory industries. The main by-products are the broken grains, le unripe grains, the bud, the flours, and the CHAFF.
Depending on the degree of processing, the amounts of rice substances also vary, part of which are in the outer layers of the grain. The semi-processed or merchant rice and rice are processed using a third whitening machine are considered to be the most reliable from the point of view of digestibility and nutrition.
In fact they ensure noble proteins such as lysine, tryptophane and methionine that are essential for growth, in the right quantities; Vitamin B and the vitamins PP, K and E; essential minerals such as Potassium, Calcium Phosphorus. Rice proteins are higher in quality than any other cereal. They contain all 18 amino-acids which are necessary for the human metabolism. It is easily digested by the human organism, just 2 hours after chewing, and is also a stabiliser for the gastric and intestinal functions and tends to make blood functions more regular.

RICE IN THE WORLD

In the world rice cultivation has increased considerably in the last fifteen years, from 135 million hectares to about 148 million. In the same period, harvesting has increased by more than 44%. The quantity of rice obtained per cultivated hectare has also improved: from 24 to 32 quintals, an increase of about 32%. It is calculated that each person in the world has about 60 kilos of rice for himself per year: i.e. 10 kilos more than five years ago. This is a true contribution, though still not enough, to the fight against hunger, with its highly dramatic phases in Africa, Asia and Latin America Latina where rice plays the role filled by bread in the Western world.
A Japanese person eats about 80 kilograms of rice per year and an inhabitant of the Indo-China peninsula uses about 150 kilos, while a European rarely exceeds 5 kilograms.

ITALIAN PRODUCTION

Our country is the largest European grower of rice. There are about 200 thousand hectares of rice fields, spread over the provinces of Vercelli, Pavia, Novara, Milan, Alessandria, Ferrara, Oristano, Mantua, Verona in that order and in some limited central and southern areas.
Annual production exceeds 11 million quintals of paddy, which amounts to 0.25% of world production. On average, 55-60 quintals are obtained from each hectare, while in the last century the figure was usually no more than 24 quintals.
The domestic market absorbs 4 and a half million quintals, the other EEC countries absorb 3 and a half million and non EEC countries absorb a little under 4 million quintals.
Italy is therefore extremely active in exporting its rice and considerable amounts of its total production are exchanged on the international market that is rather modest for rice, only 5% of the world harvest. 95 % of rice production is in fact consumed in the country of cultivation.