MAIZE STARCH PROCESSING PLANT

Starch Industry in India

Starch is an abundant carbohydrate distributed worldwide in plants. Starch has been a major ingredient in man’s diet over the centuries. In addition it has become a major industrial raw material. Plant seeds, roots and tubers are all sources of industrial starch production. The commercial realities of the starch recovery process limit the industrial sources mainly to wheat, maize and tapioca. Indian starch industry mainly consumes maize as input raw material.

Also some industries are tapioca based.

Maize is doing wonderful things in our everyday life. Maize is present in one form or other in

The Food we eat
The Milk we drink
The Chocolates/Biscuits we take
The Clothes we wear
The Paper we read
The Medicines we take
Maize (Corn) contains about 70% starch, other components being protein, fibers and fat. The basis of the maize milling process is the separation of the maize kernel into its different parts. Maize starch is produced by the wet milling process, which involves grinding of softened maize and separation of corn oil seeds (germs), gluten (proteins), fibers (husk) and finally pure starch.

Byproducts from Maize

The byproducts from maize based industries find various applications:

i. Maize (Corn) Steep Liquor: It contains amino acids, proteins and are used by antibiotics drugs manufacturers. Also it is a large source of biogas, which is being used as fuel for driers, boilers etc.

ii. Maize Gum: Corn Oil is produced by expelling oil from the germs. Corn Oil finds applications in food and other chemical industries. Maize oil cake obtained after expelling oil is used as cattle and poultry feeds.

iii. Maize Gluten: Maize Gluten contains high protein content and it is used as cattle and poultry feeds.

iv. Maize Husk: It contains starch, protein and fat as minor components and mainly consumed as cattle feed.

Starches

Starch is a group of polysacchrides, composed of glucopyranose units joined together by-glucosidric linkages. It conforms to the molecular formula, (C6-H10O5)u, where nvaries from a few hundred to over one million. Starch is found as the reserve carbohydrate in various parts of plants and is enzymatically broken down to glucose to other carbohydrates according to the metabolic needs of the plants.

Industrially, starch is broadly divided into two types viz, natural and modified. Natural starches also designated as unmodified starches or simply starches are obtained from grains such as and sorghum. From roots like potato, tapioca and arrow root, and from the pith of the stems of certain palms such a sago. They are further classified into cereal starches and root starches. The characteristics of the natural starches are changed by chemical or enzymatic action and the products of these reactions are termed modified starches. This group includes dextrins, acid-modified starches, oxidized starches, starch esters, starch ethers, aldehyde starches and cationic starches.

Natural Starches

Starch occurs naturally in the plants and its percentage varies with the plant and also in different parts of the same plant. Corn (maize) sorghum grain wheat, rice, potato, tapioca, arrowroot and sago are among the important sources of natural starches. The grains of barley, rye, oat and the millets are also employed in the production of starches.

Cereal Starches

The cereal starches such as maize wheat, rice and sorghum are recovered by several processes, of which the wet-milling is by far the most important. Other processes commercially employed in the manufacture of unmodified starches are that alkali, Martin and batter in the order of decreasing importance. Of the material methods earlier used for the production of starch and which has now become obsolete, mention may be made of the Hakka, Alsation and Fescas processes. In all the above processes, Starch is recovered in five stages:

a. Softening or steeping of the grains, after thorough washing in water.

b. Tabling or centrifugation of the ground mass.

c. Dewatering and drying of the final products.

d. The recovery of important by products.

MAIZE SCENARIO IN INDIA

The principal raw materials, used by the Indian Starch Industry are maize and tapioca.

Maize is grown in Uttar Pradesh, Bihar, Rajasthan, Punjab, Madhya Pradesh, Himachal Pradesh, Gujarat, Jammu and Kashmir, Andhra Pradesh, Mysore, and Haryana.

Among the maize growing countries India rank 4th in area and 7th in production, representing around 4% of world maize area and 2% of total production. During 2018-19 in India, the maize area has reached to 9.2 million ha (DACNET, 2020). During 1950-51 India used to produce 1.73 million MT maize, which has increased to 27.8 million MT by 2018-19, recording close to 16 times increase in production. The average productivity during the period has increased by 5.42 times from 547 kg/ha to 2965 kg/ha, while area increased nearly by three times. Though the productivity in India is almost half of world the average per day productivity of Indian maize is at par with many lead maize producing countries.

In India, maize is principally grown in two seasons, rainy (kharif) and winter (rabi). Kharif maize represents around 83% of maize area in India, while rabi maize correspond to 17% maize area. Over 70% of kharif maize area is grown under rainfed condition with prevalence of many biotic and abiotic stresses. The stress prone ecology contributes towards lower productivity of kharif maize (2706 kg/ha) as compared to rabi maize (4436 kg/ha), which is predominantly grown under assured ecosystem. In recent past spring maize area is also growing quite fast in north western parts of the country, in the states of Punjab, Haryana and Western Uttar Pradesh. Unfortunately the area and production data of spring maize is not well documented. However, informal estimate suggest the area to be around 150 thousand ha. Among cereals maize has highest growth rate in terms of area and productivity. Since last decade maize productivity in India is increasing @ over 50 kg/ha/year, which is highest among food crops.

Among Indian states Madhya Pradesh and Karnataka has highest area under maize (15% each) followed by Maharashtra (10%), Rajasthan (9%), Uttar Pradesh (8%) and others. After Karnataka and Madhya Pradesh Bihar is the highest maize producer. Andhra Pradesh is having highest state productivity. Some districts like Krishna, West Godavari etc. records as high as 12 t/ha productivity.

Bulk of the maize production in India, approximately 47%, is used as poultry feed. Of the rest of the produce, 13% is used as livestock feed and food purpose each, 12% for industrial purposes, 14% in starch industry, 7% as processed food and 6% for export and other purposes.