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After 48 hours, ''Weissella cibaria'' continued to dominate all of the grain samples except the 2016 Breiss Merit 57 (note that the 2015 harvest of Breiss Merit 57 was dominated by ''Weisella cibaria'', indicating that the barley variety is not the determining factor of which microbes might be dominant, but that the harvest year is more important). Two samples, the 2015 Breiss Merit 57 and the 2016 Blacklands Endeavor, also saw an increase in the population of ''Shiggela sonnei'' (2.5%). The ''Salmonella bongori'' was still present in samples after 48 hours, but decreased to less than 1% <ref name="blueowl_2017" />.
Some of the organic acids and alcohols were also measured in this experiment. Most of the samples created fairly high and similar levels of lactic acid, followed by a smaller amount of acetic acid, and then followed by trace amounts of citric, pyruvic, malic, and succinic acids. The 2016 Breiss Synergy had much more lactic acid, acetic acid, and noticeably more succinic acid the all the other samples. It also had considerably more ethanol produced, indicating that a heat tolerant wild yeast may have fermented this sample <ref name="blueowl_2017" />. [[Butyric Acid]] and [[Isovaleric Acid]] were not measured due to the difficulty in measuring these acids at the lab that was used <ref>[https://wwwdrive.facebookgoogle.com/groups/MilkTheFunk/permalink/1660708117290729/open?comment_id=1661783767183164&reply_comment_id=1664682886893252&comment_trackingid=%7B%22tn%22%3A%22R2%22%7D 1x6du2SvT2msELpMoW8TH5ecv9nz5dDJ8SqrI8y00GeI Edwards, John. Milk The Funk facebook group. 04/24/2017.]</ref>.
The experiment concluded that using grain to inoculate wort could potentially be done in a controlled manner, producing predictable and consistent results. It was stated that more studies need to be conducted to explore the variability in brewing process such as temperature and incubation times. For example, while the ''Weisella cibaria'' dominated at 110°F, it is reported that it doesn't tolerate temperatures above 113°F, and ''Lactobacillus'' might dominate at temperatures around 90-95°F or maybe at temperatures above 113°F <ref name="blueowl_2017" /><ref>Private correspondence with Jeff Young by Dan Pixley. 06/29/2017.</ref>.
Various concerns on possible cross contamination associated with the methodology of the referenced experiment have been discussed with the authors on [https://wwwdrive.facebookgoogle.com/groups/MilkTheFunk/permalink/1660708117290729/ open?id=1x6du2SvT2msELpMoW8TH5ecv9nz5dDJ8SqrI8y00GeI this MTF thread].
See also: