Experimental cookery

Dextrose or glucose, for it is known by both names, is widely distributed in fruits, honey, and some vegetables. The sugar known by the trade name "Cerelose" is practically a pure crystalline dextrose and is made from corn. The term dextrose or glucose should be applied to crystalline dextrose or its solution. Commercial corn sirup has been incorrectly called glucose. It is made from corn, the starch being hydrolyzed with acid. Hydrolysis is carried to the point at which 40 to 50 per cent of the starch is changed to sugar, the remainder being split into dextrins. The sirup contains both dextrose and maltose, but for convenience the sugar is usually all deter- mined and expressed as dextrose. Thus corn sirup is a mixture of dextrin, maltose, dextrose, and water. Levulose or fructose is also widely distributed in natural foods, often accompanying dextrose, or dextrose and sucrose. At present, pure crystalline levulose is expensive. Honey contains nearly equal parts of dextrose and levulose. When honey crystallizes, the greater part of the levulose is in the sirup and the dextrose in the crystals. Sucrose is widely distributed in plants, often with dextrose and levulose. The common sources of it commercially are the sugar beet, the sugar cane, the sugar maple, and the sugar palm. It is the common granulated sugar on the market and is practically pure whether obtained from the beet or cane. Maple sugar is not purified, for it would then lose the flavor for which we prize it. Maltose is formed as an intermediate product when starch is hydrolyzed by boiling with mineral acid in the manufacture of commercial corn sirup from corn. Commercially it is prepared from starch by a diastatic enzyme and it is also found in germinating cereals and malt products. Lactose is obtained from milk. One of its uses is for infant feeding. Relative Sweetness of the Sugars Sweetness is a quality that is detected by taste, but there is no exact test for it. Much depends upon how the test is conducted, whether the tongue is dry or moist, upon what part of the tongue the sample is placed, and with several other conditions, the fatigue of the sense of taste. Some persons detect sweetness in less concentrations than others. It cannot be expected that all people will agree in their estimates of the relative sweet- ness of the sugars, even with carefully worked out tests. In rating the sweetness of the various sugars it is a commonly accepted practise to rate sucrose as 100. Sugars sweeter than sucrose are ranked higher than 100, and those less sweet are ranked lower. Biester and Wood of the University of Minnesota give the following rating to sugars : EFFECT OF ACID UPON SUGARS 35 Levulose 173.3 Sucrose 100.0 Dextrose 74 . 3 Maltose 32.5 Lactose 16.0 Sale and Skinner of the Bureau of Chemistry (Water and Beverage Laboratory) rate the sugars as follows: Sucrose 100 Dextrose 50 Levulose 150 Maltose 50 Invert sugar 85 Paul in comparing the sweetness of several sugars with sucrose gives the following value : Sucrose 100 Dextrose 52 Levulose 103 Lactose 28