Moisture content of grain

K.H. Norris and J.R. Hart, Direct spectrophotometric determination of moisture content of grains and seeds, in Proceedings 1963 International Symposium on Humidity and Moisture in Liquids and Solids, A. Wexler (ed.), vol 4 Reinhold, New York, 1965 p. 19. 

Norris, K. H. (1965) Direct spectrophotometric determination of moisture content of grain and seeds. Princ. Methods Meas. Moisture Content Liquids Solids 4, 19-25. 

A control chart is a sequential plot of some quality characteristic. It might be a day-by-day plot of the average moisture content of grain samples or the concentration of a standard solution, or the percentage of a constituent in successive production lots. The chart consists of a central line and a pair of limit lines, or in some cases two pairs of limit lines for the inner and outer control limits. Plotting a sequence of points in order makes available a continuous record of the quality characteristic. Trends in data or sudden lack of precision can be made evident so that the causes... 

Determining the exact moisture content of grain is not difficult. Once done, the cultivator can easily calculate a specific moisture content that is optimal for use as spawn. Commercial rye grain, available through co-ops and feed companies, is 11 % water by mass, plus or minus 2%. The precise amount of water locked up in grain can be determined by weighing a sample of 100 grams. 

A common method for determining moisture content of grains and oilseeds is to dry samples in triplicate in a convection air oven at a specified temperature for a specified duration (Table 27.7 ASAE [12]). About 10-15 g samples are weighed in covered aluminum dishes. The dishes are uncovered and placed with their covers in the oven at the set temperature. At the end of the drying period, dishes are covered and placed in a desiccator for cooling to the room temperature. The dishes with dried sample are weighed again. Moisture content of samples is calculated as the ratio of the... 

Brockelsby, C.F., An instrument for estimating the moisture content of grain and other materials by the measurement of electrical conductance. Cereal Chem., 28 83—94 (1951). 

Why is the moisture content of grains important when buying feed and when balancing rations ... 

Adsorption for gas purification comes under the category of dynamic adsorption. Where a high separation efficiency is required, the adsorption would be stopped when the breakthrough point is reached. The relationship between adsorbate concentration in the gas stream and the solid may be determined experimentally and plotted in the form of isotherms. These are usually determined under static equilibrium conditions but dynamic adsorption conditions operating in gas purification bear little relationship to these results. Isotherms indicate the affinity of the adsorbent for the adsorbate but do not relate the contact time or the amount of adsorbent required to reduce the adsorbate from one concentration to another. Factors which influence the service time of an adsorbent bed include the grain size of the adsorbent depth of adsorbent bed gas velocity temperature of gas and adsorbent pressure of the gas stream concentration of the adsorbates concentration of other gas constituents which may be adsorbed at the same time moisture content of the gas and adsorbent concentration of substances which may polymerize or react with the adsorbent adsorptive capacity of the adsorbent for the adsorbate over the concentration range applicable over the filter or carbon bed efficiency of adsorbate removal required. 

The original applications of NIR were in the food and agricultural industries where the routine determination of the moisture content of foodstuffs, the protein content of grain and the fat content of edible oils and meats at the 1% level and above are typical examples. The range of industries now using the technique is much wider and includes pharmaceutical, polymer, adhesives and textile companies. The first in particular are employing NIR spectrometry for the quality control of raw materials and intermediates and to check on actives and excipients in formulated products. Figure 9.26(b) demonstrates that even subtle differences between the NIR spectra of enantiomers can be detected. 

This method is used for determining the moisture content of small grain or flake propints. Single,-double or triple base proplnts can be used. The principle of the method is measurement of the current required for electrolysis... 

This method is used for the determination of moisture content of small grain or finely divided cannon propellant. It is based on distillation of the moisture with a solvent that... 

Finely ground nitrocellulose of low viscosity was used. It was impregnated with DGDN under water in the usual way. After dehydration in a centrifuge to a moisture content of 18-22%, the blend was stirred into molten TNT. The vat was evacuated to evaporate the water and to produce a homogeneously gelatinized grain. 

This method is used for the determination of moisture content of small grain or finely divided cannon propellant. It is based on distillation of the moisture with a solvent that is immiscible with and heavier than water. Trichloroethylene is the preferred solvent, but carbon tetrachloride is also satisfactory. This method is not suitable for pioplnts containing less than 0.2% moisture. The presence of hydrated compds may cause high results. The presence of finely divided aluminum may cause a reaction with the chlorinated solvent and, in such cases, tests should be made to demonstrate compatability of proplnt and solvent... 

Atmospheric air is cleaned by passage through electrostatic filters, compressed to about 10 p.s.i.g. by five 400-cu. foot per minute rotary blowers, cooled by water coils, followed by refrigerated coils, to under 50 F., thereby drying to under 50 grains of moisture per pound of dry air, and passed through one of four crushed aluminum dryers to produce dew points below —60 F., equal to a moisture content of less than 1 grain per pound of dry air. 

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