Volume 1

The modern baker, confectioner and caterer : a practical and scientific work for the baking and allied trades / edited by John Kirkland ; with contributions from leading specialists and trade experts.

Date:
1911
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: The modern baker, confectioner and caterer : a practical and scientific work for the baking and allied trades / edited by John Kirkland ; with contributions from leading specialists and trade experts. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    this view. Whilst it is difficult to truce actual epidemics to its use, there is strong reason for believing that it may set up diarrhoea. On the other hand, fowls fed exclusively upon such wheat have not suffered in any way. There can be no doubt that it would be better to dispose of such wheat as fodder, rather than risk the possible consequences of usinof it for the manufacture of human food. Rust, Corn Mildew (Uredo rubigo vera, and Uredo linearis).—The rusts are the most widely spread of all cereal diseases, the loss of crops due to them sometimes reaching from 50 to 75 per cent. Rust or Botanists group these diseases together under the head of Corn Mlldew- the Uredinese. The disease in all cases has two stages in wheat, known respectively as Rust and Puccinia. In the first or Rust stage, small pustules of a reddish colour are seen upon the stems and leaves of the plant. These in time disappear, and are replaced with black patches. The pustule is caused by the growth of the sori or spore heads under the integument, which is thus forced up into a small bleb; this finally ruptures and allows of the escape of the spores. The spore of the Rust stage is small, round, and black; it gives rise to the second or Puccinia stage, which in its turn produces a form of double spore (teleutospore) with pointed end. Rust is now known to be a disease communicated to wheal from barberry bushes, upon which this fungus passes a third stage of its existence, and forms resting spores which germinate only after some months, producing the Rust stage in the grasses. There are two kinds of Rust with their respective Puccinia; they are known as Spring Rust (Uredo rubigo vera) and Summer Rust (Uredo linearis). Recent re- searches bearing upon Mendel’s theory of heredity have shown that the liability to this disease is inherited, and, therefore, that selection of re- sistant varieties offers a prospect of stamping this disease out. Smut (Ustilago carbo) is also a very common disease of wheat, and in bad cases as much as one-third of the crop may be destroyed. Smut appears to attack the plant at the root, thence passing upwards into the ears, which become covered with a sooty deposit consist- mu ’ ing of the spores. These spores are very small, about '005 mm., quite round, and perfectly smooth, dark-brown in colour. They are capable of reproduction by budding, and in this they closely resemble the yeasts. The disease is common to a large number of grasses, and its spores may often be found in flour in small number. Smut has no smell, but if smutted wheat is used in large quantity the colour of the flour suffers. Experiments in feeding smutted wheat to animals have had no injurious results. Nothing is known of its effects upon the human system, but it is said to impart a disagreeable flavour to bread if present in large quantity. Ergot (Glaviceps purpurea).—Dietetically this is by far the most dangerous of the cereal diseases. Ergots are small, blackish, cucumber- like excrescences, which may be sometimes seen growing from the ripening ears of rye, and, less frequently, wheat, barley, &c. An Ergot- ergot is really the sclerotium or hard mycelium of the fungus Claviceps