Second. Farinaceous substances of low price, as spice damaged in transportation or by long storage, middlings, corn meal, and stale ship bread.
Third. Leguminous seeds, as peas and beans, which contribute largely to the profit of the mixer.
Fourth. Various articles chosen with reference to their suitableness to bring up the mixtures, as nearly as possible, to the required standard color of the genuine article; various shades from light colors to dark brown may be obtained by skillful roasting of the farinaceous and leguminous substances, and a little tumeric goes a long way to give a rich yellow color to real mustard made from pale counterfeit of wheat flour and terra-alba, or the defective paleness of artificial black pepper is brought to the desired tone by judicious sifting in of a finely pulverized charcoal.
From what has been said of the different foreign substances used for adulterations of spices and condiments, the necessity of knowing the structure and formation of the molecules of both principal and foreign elements which constitute the principal tissues of the particular plant-parts used for the adulterations is apparent, while in the chemical examination the principle of proximate analysis must be understood and applied.
It is also necessary that the analyst should be thoroughly acquainted with the application of the microscope, to determine the cellular structure, to make determinations of proximate principles in the substances under examination, since a mechanical separation by the microscope is more expeditious and is more at the command of the majority of persons searching for adulterations. For a mechanical analysis of food separations, a powerful microscope of good workmanship is required. It is better if it is supplied with a substance condenser and Nical prisms for the use of polarized light. Objectives of an inch and half inch, and, for some starches, one-fifth inch, equivalent focus, are sufficient. One eye-piece of medium depth, one-fourth to one-sixth, adjusted at 160 degrees is enough, with plenty of good light. The analyst should also have plenty of sieves of 40 to 60 meshes to the inch to be used for separation, which will furnish means of detecting adulterants and selecting particles for investigation, and will often reveal the presence of foreign material without further examination, since many adulterants are not ground so fine as the spices to which they are added, and by passing the mixtures through the sieves the coarser particles remaining will be either recognized at once by an unaided educated eye or with a pocket lens.
In this way, tumeric is readily separated from mustard and yellow corn meal; mustard hulls and cayenne, from low-grade pepper. Where a pocket lens is insufficient, the higher power of the microscope is confirmatory. It is also desirable to be provided with a dissecting microscope for selecting particles for examination from large masses of ground spice, and for this a large Zeiss stand, made for that purpose, is best, but simpler forms, or even a hand lens, will answer the purpose. For smaller apparatus, a few beakers, watch crystals, stirring rods, and specimen tubes, with bottles for reagents, will be sufficient, in addition to the ordinary glass slides and covers for glasses. The reagents required for chemical analysis (if no great amount is used) are as follows:
Strong alcohol,
Ammonia,
Chloral-hydrate solution—8 parts to 5 of water,
Glycerine,