Microbiological Quality, Shelf Life and Fermentation Activity of Active Dried Yeast
Abstract
The microbiological quality and shelf life of 10 active dried yeast preparations were determined. The dried yeasts were tested for total microbial count, total yeast count, total wild yeast count, total bacterial count, spore forming bacteria, Enterobacteriaceae and lactic acid bacteria. For the shelf life test, the yeasts were stored at 0°C, 4°C, 15°C and 25°C for six months and tested at monthly intervals for total viable yeast count and total bacterial count. After six months storage fermentations were carried out in Colombar must and the wines subsequently analysed. All dried yeasts complied with the International Wine Office ( 0 .I. V.) guideline of 1 x 109 viable yeasts per gram dried yeast, whilst only some preparations complied with the guideline for total bacterial count of 1 x 105 bacteria per gram dried yeast. Results of the shelf life test showed optimum storage temperature to be 4°C.Downloads
Copyright (c) 2017 South African Society for Enology and Viticulture

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
A copyright form will be e-mailed to the corresponding author when the manuscript has been accepted for publication.
In principle, the Author agrees to the following when he/she signes the copyright agreement:
I hereby assign to the SOUTH AFRICAN SOCIETY FOR ENOLOGY AND VITICULTURE (SASEV) the copyright of the text, tables, figures, supplementary material, illustrations and other information (the Material) submitted with the manuscript to be published in SOUTH AFRICAN JOURNAL OF ENOLOGY AND VITICULTURE (SAJEV) (the "Article"). The copyright becomes effective from the date the Article has been accepted for publication in SAJEV.
This is an open access journal, and the authors and journal should be properly acknowledged, when works are cited.
Author's may use the publishers version for teaching purposes, in books, theses, dissertations, conferences and conference papers.
A copy of the authors' publishers version may also be hosted on the following websites:
- Non-commercial personal webpage or blog.
- Institutional webpage.
- Authors Institutional Repository.
The following notice should accompany such a posting on the website: This is an electronic version of an article published in SAJEV, Volume XXX, number XXX, pages XXX - XXX, DOI. Authors should also supply a hyperlink to the original paper or indicate where the original paper (www.journals.ac.za/index.php/sajev/) may be found.
Authors publishers version, affiliated with the Stellenbosch University will be automatically deposited in the University's Institutional Repository SUNScholar.
Articles as a whole, may not be re-published with another journal.
The following license applies:
Attribution CC BY-NC-ND 4.0