Patents by Inventor Graham G. Stewart

Graham G. Stewart has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4772556
    Abstract: The present invention relates to a stable, allopolyploid, somatic fusion product useful in the fermentation arts and especially in the production of fuel alcohols. More particularly, the present invention relates to a novel allopolyploid yeast strain, Saccharomyces diastaticus NCYC 1460, which is the product of the spheroplast fusion of:(a) a hybrid, diploid strain of Sacch. diastaticus; and(b) a fusion partner which is a polyploid brewing yeast strain of the species Saccharomyces uvarum (carlsbergensis).The fusion product of the present invention is capable of an enhanced rate of fermentation and a generally higher degree of final attenuation than is typical of either of the fusion partners. Moreover the fusion product also evidences enhanced osmo- and thermo-tolerances and its multiple, non-allelic DEX gene complement renders the organism well suited to the fermentation of substrates containing dextrins and oligosaccharides.
    Type: Grant
    Filed: July 14, 1986
    Date of Patent: September 20, 1988
    Assignee: Labatt Brewing Company, Limited
    Inventors: Graham G. Stewart, Ingeborg Russell, Chandrakant J. Panchal
  • Patent number: 4676986
    Abstract: The present invention relates to amylolytic enzymes produced by strains of Schwanniomyces castellii which enzymes are relatively thermolabile under the conditions used to pasteurize beer. The present invention is also concerned with a novel strain of Schwanniomyces castellii which is a derepressed producer of alpha-amylase. Also disclosed is an improved process for the production of low carbohydrate beers and in particular, low calorie beers, from high gravity worts which improvements are facilitated through the use of culture filtrates derived from viable cultures of Schwanniomyces castellii.
    Type: Grant
    Filed: May 20, 1986
    Date of Patent: June 30, 1987
    Inventors: Alexander M. Sills, Graham G. Stewart
  • Patent number: 4409246
    Abstract: The specification discloses a novel brewers' yeast strain and a method of manufacturing the same. The yeast is a strain of Saccharomyces cerevisiae and has been deposited at the National Collection of Yeast Cultures, Norwich, England under the number 962. Morphologically the giant colony of the novel strain can be described as a circular colony having a slightly serrated periphery, a convex surface topography with a central, globular dome and exhibiting primary concentric convolutions and secondary radial convolutions which, in combination, impart a rough appearance to the surface. The novel ale strain has the advantages that it is effective in worts having high plato values and is a bottom-cropping strain.
    Type: Grant
    Filed: July 22, 1981
    Date of Patent: October 11, 1983
    Assignee: Labatt Brewing Company Limited
    Inventors: Graham G. Stewart, Thomas E. Goring, Ingeborg Russell