Rice cleaning process

Modern rice mills perform the milling process mechanically, starting with cleaning the field-run grain and ending with milled rice which has been sorted into grades.

Cleaning is a material separation process. The objective is to separate undesirable foreign materials from the paddy and leave a cleaned paddy for storage and process. The paddy procured from the farmer may be dried, if necessary and stored in storage bins, and then it is cleaned with the help of paddy cleaners.

The removal of impurities from grain is essential to protect the subsequent milling machinery from unusual wear and tear as well as to improve the quality of the final product.

Rough cleaning precedes drying, which is usually done in upright continuous flow dryers with a concurrent flow of heated air. After cooling, the dried rice is cleaned by various separation methods to give rough rice or “paddy”.

The cleaning process involves
*scalping to remove sticks, mud lumps, etc
*bearding to remove the awns, culms and leaves
*monitoring or cleaning to remove sterile florets and any remaining foreign matter.
Rice cleaning process

Cleaning in place (CIP)

Today, in many food industries, cleaning in place (CIP) is not only a cleaning method but a strategic decision built into the design of the plant and its individual parts.

Among the advantages of CIP:
*Permit on-site cleaning
*Substantial increases in processing capacity
*Reduced losses through the application of CIP cleanable automated vales and highly automated process
*Minimizes downtime
*Improved quality of all products and significant improvement in perishable products
*Reduced labor for both processing and cleaning

An additional advantage is that the cleaning agent/solvent quantities necessary for CIP is less than for conventional cleaning.

Basically CIP is a hydrodynamic cleaning process where rinsing, cleaning and sanitizing fluids circulate along with the path of the products and provide the detergency as well as the mechanical action needed for the removal of soil, without dismantling the line.

It is an economical method of maintaining the processing line at peak performance and extending it operating life. It is recommend that regular CIP cleaning is included in the preventive maintenance program to maximize processing performance and minimize the system operating costs and overall maintenance cost.

With its controlled, monitored, documented and reliably reproducible cleaning result, CIP fulfills the GMP (good manufacturing practices) requirements.
Cleaning in place (CIP)

Processing of green and wax beans

At the processing plant, beans are sorted out for size, washed and their ends are snipped off mechanically. They are then cut transversely or longitudinal and blanched.

Some beans are frozen individually and placed in plastic pouches alone or as a component of mixed vegetables or they may be first packaged and then frozen in a blast freezer. Some beans are canned in brine and processed.

Canning and freezing are the two most commonly used commercial methods of processing the beans. Other products such as purees for the beans are marketed as baby foods or specialty applications.
Processing of green and wax beans

Grain processing: cleaning

Grain cleaning reduces the problems that occur during storage and handling. Clean grains save storage space and increase marketability.

Over the years there has been rapid development of machinery for grain cleaning. The one most often used employ the air screen system, which was the basis for the oldest cleaning machines and still is the easiest and most effective form of cleaning bulk grain.

The mill is the point where cereals are transformed from agricultural commodities to foods or food ingredients.

Physical cleaning takes place in the mill to remove straw and chaff, stones, soil and metal fragments, which could damage the mill, damaged or ergot-infected grains, seed other than the cereal grain required, insects and other foreign matter.

In preparing wheat cleaning, the wheat is blown into hopper scales that record the quantity of uncleaned wheat. Some of the coarser impurities are removed by this process.

The grain then passed over a series of coarse and fine sieves that further remove contaminating materials, including chaff and straw.

The various dry cleaning processed used in modern four mills have little effect on the microbiological condition of the grain.

The efficiency of the cleaning operation is dependent on the efficiency of the machine, the selection of appropriate screens for the particular task and the competence of the operator.
Grain processing: cleaning

Cleaning process of cocoa raw beans

The first process that must precede the manufacture of chocolate or cocoa is that of cleaning. Raw beans contain surface frit, occasional small stones and hessian fibers. Impurities may cause wear and damage to subsequent processing machinery.

The raw cocoa beans are cleaned by passing them over a shaking table covered with a metal screen which has holes smaller in size than the beans.

A set of vibrating screens removes both very large and very small particles by sieving.

The machinery consist of a series of separations, which by means of screens of varying meshes, brushes, air lifts and magnetic separators – removes fiber, stones and grit, metal bean cluster and immatures.

Sand, dust and other foreign material are screened out. Stones, metals and other heavy materials drop to the bottom of the chute which is counterpoised by weighted lever.

Removal of dust and sand is very important, due to its abrasive nature, which will rapidly wear the balls mills, or the surface of refiner rolls.

Immature beans and clusters not be allowed to proceed to roasting and subsequent manufacturing processes, but may be included in bean blends with other winnowing products for expeller pressing to produce cocoa butter.
Cleaning process of cocoa raw beans

Wheat cleaning and milling

Before the wheat reaches the milling stage, first it has undergo several preliminary operations that ensure the correct of the main process. The first of these is wheat cleaning.

Wheat is passed through a series of machines that apply the principles of particle size and density separation.

Foreign materials such as metal, sticks, stones, straw, seeds and other grain are removed in steps by a magnetic separator, vibrating screens, a destoner, a disc separator and a scourer.

Sieves remove contaminants larger than wheat kernels as well as finer contaminants such as sand. In addition, air is used to remove plant material that is lighter than the grain.

After cleaning, the wheat is tempered prior to be milled. In this stage, the moisture content of the grain is increased by adding water and by allowing the grain to sit for a period of time.

Wheat is milled to remove the bran and germ and reduce the wheat kernel to flour to be used in various baked and nonbaked goods.
In general, 100 pounds of wheat will produce 72 pounds of flour. The aimed of white flour milling is to extract a maximum amount do endosperm from the wheat berry in as pure a form as possible.

The wheat is passed through a series of machines to break open the wheat kernels and reducing of the endosperm by grinding to obtain the final product – plain flour.

Additives of less than 1 weight % are added to the flour by a mixing process.

Family four for retail sale is packed in 5, 10, or 25 pound bags. Bakery flour may be packed in 50 or 100 pound bags or shipped in bulk trucks or railcars.

Wheat cleaning and milling

Process of wheat cleaning

Most grain are not cleaned either by farmers or by country elevators. Wheat delivered at an elevator is sampled and graded with considerable accuracy and the elevator operator usually makes a price adjustment on the basis of moisture content, test eight, foreign material and damaged or broken kernel.

The mill is the point where cereals are transformed from agricultural commodities to foods or food ingredients.

Wheat cleaning is related to the flour yield and ash content. A great deal of physical cleaning takes place in the mill.

It must be clean of all impurities because impurities increase the ash content of the flour, adversely affect four color, and reduce the flour yield.

The grain must be carefully cleaned and all foreign grains (cereals other than wheat and fodder plants), stones and metallic particles are removed. The cleaning operations separate the impurities and foreign sees by dimension, weight and form.

Wheat cleaning operation consists of cleaning operation in the first stage, involving the use of:
*rubble separator to remove gross contaminants
*disc separator to remove weed seeds and broken grains
*magnetic separator to remove pieces of metal and
*wash and whizzer device where wheat is rapidly sluiced round at high speed in a stream of water to remove dirt.

Milling and mixing of the cleaned wheat are carried out in the production section.

Process of wheat cleaning