In our opinion any one of these methods skilfully and properly carried out will yield a marketable, hygienic and wholesome product, though some of them can boast of their own particular advantages. This holds good for the so-called “Dutch” method in particular, though it is open to the objection that the cacao so prepared is combined with an extraneous product and that the combination remains right up to the moment of consumption. Considered from this point of view, disintegration with fixed alkalis is generally less advisable than the optional treatment with water or volatile alkali, but it may be taken for granted that each manufacturer had better decide the several details best adapted to his own particular outfit. A well made soluble cocoa powder should have a pure brown colour, without any suspicion of grey, should be perfectly dry, and feel light and soft when finely divided, so betraying that property which the French designate under the term “impalpable The peculiar aroma of the cacao must be retained, and especially should the preparation be preserved from the slightest taint of any ammonia combination, its taste being kept pure and cacao-like, any hint of alkalinity indicating defect in the manner of disintegration. Over and above delicacy of aroma and taste, that characteristic described as “solubility” constitutes a main criterion of quality in the eyes of the consuming public. To ascertain that only an empirical test can be employed.[133] About 7·5 grammes of cocoa powder are introduced into some 150 grammes of hot milk or hot water contained in a graduated beaker, and then the quantity of sediment which sinks to the bottom of the vessel in a given time is noted. The more slowly a sediment is formed and the smaller it is, the greater the “solubility” of the cocoa. If it becomes necessary to give the cacao an additional flavouring, the spices or ether-oils generally employed in the manufacture of chocolate may be used in the course of pulverisation, and shortly before sifting. C. Packing and Storing of the finished Cacao Preparations. Chocolate will keep in its original condition for years, when protected from atmospheric influence. It is therefore generally, and especially where the finer qualities are concerned, packed up immediately after it leaves the last process, and ornamented chocolates are previously varnished with an alcoholic solution of benzoin and shellac (see page 250). The inferior qualities are usually packed in paper and wooden boxes, but the superior first in tin-foil and subsequently in paper. ~Cocoa powder~ arrives packed in parchment boxes as a rule, and also in cardboard or tin boxes.