h the brewing industry. It was formerly believed that by the
action of diastase on starch the latter is first converted into a gummy
substance termed dextrin, which is then subsequently transformed into a
sugar--glucose. F.A. Musculus, however, in 1860, showed that sugar and
dextrin are simultaneously produced, and between the years 1872 and 1876
Cornelius O'Sullivan definitely proved that the sugar produced was maltose.
When starch-paste, the jelly formed by treating starch with boiling water,
is mixed with iodine solution, a deep blue coloration results. The first
product of starch degradation by either acids or diastase, namely soluble
starch, also exhibits the same coloration when treated with iodine. As
degradation proceeds, and the products become more and more soluble and
diffusible, the blue reaction with iodine gives place first to a purple,
then to a reddish colour, and finally the coloration ceases altogether. In
the same way, the optical rotating power decreases, and the cupric reducing
power (towards Fehling's solution) increases, as the process of hydrolysis
proceeds. C. O'Sullivan was the first to point out definitely the influence
of the temperature of the mash on the character of the products. The work
of Horace T. Brown (with J. Heron) extended that of O'Sullivan, and (with
G.H. Morris) established the presence of an intermediate product between
the higher dextrins and maltose. This product was termed maltodextrin, and
Brown and Morris were led to believe that a large number of these
substances existed in malt wort. They proposed for these substances the
generic name "amyloins." Although according to their view they were
compounds of maltose and dextrin, they had the properties of mixtures of
these two substances. On the assumption of the existence of these
compounds, Brown and his colleagues formulated what is known as the
maltodextrin or amyloin hypothesis of starch degradation. C.J. Lintner, in
1891, claimed to have separated a sugar, isomeric with maltose, which is
termed isomaltose, from the products of starch hydrolysis. A.R. Ling and
J.L. Baker, as well as Brown and Morris, in 1895, proved that this
isomaltose was not a homogeneous substance, and evidence tending to the
same conclusion was subsequently brought forward by continental workers.
Ling and Baker, in 1897, isolated the following compounds from the products
of starch hydrolysis--maltodextrin-[alpha], C_{36}H_{62}O_{31}, and
maltodextrin-[b