Improvements in Preserving Yeast for Transport.
Year: 1893

page_text: Date of Application, 11th Feb., 1893
Complete Specification Left, 13th Nov., 1893—Accepted, 16th Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in Preserving Yeast for Transport.
I, JOHN HERON F.I.C., F.C.S., of Southampton Wharf, Battersea, in the
County of Surrey Consulting Chemist, do hereby declare the nature of this
invention to be as follows:-
My invention has reference to preserving yeast for transport. Yeast has hitherto
generally been preserved by incorporating it with plaster of paris. When it is
subsequently required to use the yeast, as in brewing for example, the mixture of
yeast and plaster is put into the wort or liquor whereby the yeast is set free and is
then able to act so as to set up the required fermentation. But this method of
preserving the yeast is not always to be relied upon and has the objection that an
excess of sulphate of lime is introduced into the liquor to be fermented.
Now according to my invention I preserve yeast by first pressing it in a filter
press and then incorporating it either with glucose, lævo saccharum, glucose syrup
or cane sugar syrup whereby the preservation is effected with greater certainty
than when plaster of paris is used, and further any introduction of objectionable
matter into the liquor is avoided because the glucose and other above mentioned
saccharine substances are themselves fermentable and as such are largely employed
in brewing.
In carrying out my invention I preferably employ dextro-glucose. I concentrate
this as far as possible so as to reduce the amount of water therein and enable it to
take up or absorb some of the moisture contained in the yeast; or alternatively I
concentrate the glucose to about the usual gravity and submit the yeast to more
than the ordinary pressure so as to make it drier than is customary, the point
being that the glucose and the yeast shall contain between them only sufficient
moisture to enable them when mixed together to set and form a compact hard mass.
I mix the glucose and yeast together and thoroughly incorporate them by stirrers
or otherwise and I then put the mixture into moulds or other receptacles and leave
them to set and harden.
Without limiting myself to any particular proportions of glucose and yeast, I may
state that I consider one part by weight of ordinary pressed yeast to four parts by
weight of extra concentrated glucose suitable proportions.
Dated this 11th day of February 1893.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.
COMPLETE SPECIFICATION.
Improvements in Preserving Yeast for Transport.
I, JOHN HERON F.I.C., F.C.S., of Southampton Wharf, Battersea in the
County of Surrey, Consulting Chemist, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
My invention has reference to preserving yeast for transport. Yeast has hitherto
generally been preserved by incorporating it with plaster of paris, starch or some
other absorbent material or by drying it between sheets of blotting paper with or
without the aid of heat. When it is subsequently required to use the yeast, as in
brewing for example, the mixture of yeast and plaster or other material is put into
the wort or liquor whereby the yeast is set free and is then able to act so as to set
up the required fermentation. But these methods of preserving the yeast are not
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page_text: always to be relied upon, the activity of the yeast being greatly impaired, besides
which objectionable matters are introduced along with the yeast into the fermentable
liquid.
Now according to my invention I preserve yeast in such a manner that when
subsequently used no objectionable matters are introduced with it into the liquid,
whilst the activity of the yeast is not impaired to any appreciable extent.
With
this object having first pressed the yeast in a filter press such as is ordinarily
employed for the purpose I thoroughly incorporate it with glucose in the form of
either dextro-glucose, lævo-glucose or saccharum, glucose syrup, or cane sugar
syrup, or of a mixture of any two or more of these, whereby the preservation of the
yeast is effected with greater certainty than by any of the methods hitherto
employed, and further the introduction of any objectionable matter into the liquid
to be fermented is avoided because the glucose introduced with the yeast is itself
fermentable and as such is largely employed in the brewing of beer.
In carrying out my invention I preferably employ what is known commercially as
solid glucose or dextro-glucose. I concentrate a solution of this until it contains
only about 10 to 12 per cent. of water, or alternatively I concentrate the glucose
solution to about the gravity in which it is usually employed for brewing and
submit the yeast to more than the ordinary pressure so as to make it drier than is
customary, the point being that the glucose and the yeast shall contain between
them only sufficient moisture to enable them when mixed together to set hard and
form a compact solid mass. I mix the glucose when cold and the yeast together
and thoroughly incorporate the one with the other by means of stirrers or paddles
(worked by hand or machinery) or otherwise and I then put the mixture into moulds
or other receptacles and leave it to set and harden.
Without limiting myse to any particular proportions of glucose and yeast, I may
state that I consider one rt by weight of ordinary pressed yeast to four parts by
weight of extra concentrate 1 glucose suitable proportions.
My invention is applicable to the preservation of all kinds of yeast such for
example as brewers', distillers', cider makers', bakers', &c.
When it is applied to the preservation of any of the varieties of yeast known as
"pure yeast" care should be taken to sterilize the glucose and all utensils employed
in the operation previous to use.
When it is intended that the yeast preserved as above described shall be used for
brewing beverages such for example as ginger beer in which sweetness is desirable
a suitable proportion of saccharin may be added to the glucose before its
incorporation with the yeast.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The preservation of yeast for transport by incorporating it with glucose substan-
tially as herembefore described.
ly as herembefore described.
Dated this 10th day of November 1999.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.
Dated his 10th day of November 1999.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.