Wheat falling number: what it is and what it affects, how to determine the value

Flour obtained from grains of cereals is the most important product of its processing. Flour for baking bread and bakery products is usually obtained from soft wheat varieties. The quality of flour affects the quality of flour products. It is determined by different methods. Consider the value of the fall number of wheat, what it is, the calculation technology, how the indicator affects the quality of future bread.

What is the fall number of wheat

One of the main criteria for the baking quality of flour is autolytic activity, which is determined by the intensity of the processes occurring in the manufacture of dough and baking products from it.This is the ability of flour to form substances under the influence of enzymes or when the flour mixture is heated.

Determination of autolytic activity by the number of falling is based on the level of viscosity of the water-flour mixture when heated in a boiling bath for 1 minute of time. For grain from wheat, the fall frequency value should be 250 seconds.

The falling number is an indicator of the activity of alpha-amylase, an enzyme in wheat, barley, rye, triticale and products derived from them.

Computation technology

Activation of the alpha-amylase enzyme occurs during grain germination. Protein breaks down starch into sugars. At the same time, the quality of raw materials falls, products from it are of poor quality: small in size, dryish and quickly stale.

The higher the activity of the enzyme, the more intensive the destruction of starch will be, in this case the indicators will be low. The unit of measurement of the characteristic is considered to be the second.

The falling number is measured by the Hagberg-Perten method, based on the gelatinization of ground grain or flour in a test tube that is heated in a boiling bath, and determining the rate of enzyme activity.

Preparation

Enzyme activity is measured using a colorimetric method. The analysis will require special instruments (colorimeter and stopwatch) and solutions of calcium chloride, iodine and a buffer solution. As well as special equipment in the form of a centrifuge, a laboratory mill and a sieve, and measuring instruments, a scale and a ph meter.

Preparation for measurement includes sampling of grain from 300 g storage facilities, grain moisture should not exceed 18%. Wet grain is dried and cleaned of unwanted impurities. In the laboratory, the grain is ground, sifted through a fine sieve, 2 samples weighing 7 g each are taken from the raw material obtained.

Mixing

Flour is poured into test tubes, 25 ml of distilled water is poured into them, the temperature of which should be 20 ° C. The tubes are sealed with stoppers. The contents are mixed by shaking to make it homogeneous.

Analysis

The water bath in the appliance is heated to a boil. Test tubes without stoppers are placed in the device and the stirrer rod is lowered into them. After 5 seconds, the instrument starts moving the tubes vertically at a frequency of 2 Hz. The mixture begins to thicken, swell, gelatinize, the process of enzyme activation and starch breakdown begins.

After a minute, the stirrer rod should descend to the bottom of the tubes. The drop time is affected by the degree of resistance of the water-flour mixture.

What determines the reliability of the result

There may be errors at each of the measurement stages.They arise due to the non-compliance of flour with the requirements of the standard (large or, conversely, small), improper humidity, high or low temperature of the sample. Adjustments are made by insufficiently accurate scales, non-observance of mixing time, insufficient temperature of the water bath.

Influence of the falling number on the quality of bread

Good quality flour is average. Both low and too high indicate its poor quality.

Low performance

A low number indicates that the flour is made from sprouted grains. It is in germinating wheat that the amount of enzyme increases, the dough from it spreads, the crumb of bread becomes inelastic, sticky, with a rough, uneven porosity. Poor quality of the product negatively affects the volume and taste of the bread. Raw materials with low rates are not recommended to be recycled.

High quality performance

They indicate the low activity of the enzyme in the flour, which is necessary for the normal fermentation process, the acquisition of plasticity and elasticity by the dough. High performance flour is obtained from grain that has been dried at a high temperature. The dough from it does not rise well, the volume of the finished product decreases, the bread turns out to be insipid, with a slight smell, and a pale color.

Flour falling number - an indicator that is used to characterize the quality of grain and flour obtained from it. Standard for wheat flour 2 grades - 160 seconds, for other varieties - 185 seconds