Development of semi-synthetic bread substrates for examination of bread spoilage organisms

Michael Enk, Per Væggemose Nielsen

    Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearch


    Shelf life studies of bread are highly irreproducible due to the very heterogenous structure of bread and the difficulties in obtaining sterile bread. We hypothesize that novel semi-synthetic bread substrates with chemical and microbial properties similar to those of bread can be developed. The bread based substrates can prove valuable in predicting shelf life of bread and in the routine hygienic control of bread factories.Our objective was to develop substrates with properties, which both chemically and microbiologically resembles those of dark and white bread respectively.Nineteen dark (DB) and 19 white (WB) bread based substrates were made based on a factorial design. Lactic acid, acetic acid, propionic acid, ethanol and glucose were added in amounts found in different brand of bread by chemical analysis. Water activity was adjusted by polyethylene glycol. The substrates were evaluated chemically and by growth studies of eight fungal and three yeast species isolated from bread.Several of the substrates showed chemical properties and microbial growth similar to that of bread. Lactic acid had a significant effect on the microbial growth and on pH. High water activity (more than 0.95) supported growth of all examined species. Glucose did not show any influence on the growth. High content (20 g/kg) of bread granulate were better in supporting growth.The results show that it is possible to develop substrates, which both chemically and microbiologically resembles bread. The developed substrates can easily be modified to support local spoilage organisms, which varies among countries, simply by changing the bread granulate, without changing the amount of added chemicals.
    Original languageEnglish
    Title of host publicationBook of abstracts, IFT annual meeting 1998
    Place of PublicationChicago
    Publication date1998
    Publication statusPublished - 1998
    EventInstitute of Food Technology, annual meeting 1998 - Atlanta, USA
    Duration: 1 Jan 1998 → …


    ConferenceInstitute of Food Technology, annual meeting 1998
    CityAtlanta, USA
    Period01/01/1998 → …

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