In Search of Perfect Growth Media for Baker's Yeast Production: Mapping Patents

Abstract

Baker's yeast is a key ingredient for bread and, on the long term, changes in its manufacturing process had a major impact on the baking industry. As shown by a review of 236 patents filed between 1900 and 2009, the development of suitable growth media for baker's yeast was critical to improve its acceptability by the baking industry mainly through reduced cost and improved appearance (pale color). Based on the abandon of patenting activity on artisan yeast production in dough, acceptable commercial baker's yeast appeared on the North American market around 1920, but probably 5 to 15 y earlier in Europe partly because German inventors were the most active to develop growth media for baker's yeast. During the same period, grain-based media were replaced by diluted molasses that was cheaper. In the following 20 y, inventors put much energy on molasses clarification and miscellaneous sources of nitrogen to supplement it. Although molasses remains the basic raw material for baker's yeast manufacturing, alternatives are still sought for this application. In the early patent literature, cases were found where several inventors claimed intellectual property rights for the same invention described in patents filed in different countries and languages, which suggests that only thorough reading of patent specifications may distinguish inventorship from licenses and thus truly estimate patenting activity.

Bread Dough and Baker's Yeast: An Uplifting Synergy

“…Many different growth media are available and suitable for yeast growth (Zonneveld 1986;Gélinas 2012;Basu and others 2015). Essentially, they contain glucose, the preferred carbon source of S. cerevisiae, and ammonium salts as a nitrogen source (Bergman 2001; Alvarez-Vasquez and others 2007; Galdieri and others 2010).…”

“…This growth medium contains all nutrients necessary for optimal yeast growth. On an industrial scale, beet and cane molasses are mostly used for yeast production (Gélinas 2012;Randez-Gil and others 2013). As stated before, molasses does not always provide the desirable amount of nitrogen for yeast growth.…”

Aeration and Foam Control in Baker's Yeast Production: Mapping Patents

“…For a few patents, this German inventor from Mannheim was linked to a German manufacturer, Norddeutsche Hefeindustrie AG, based in Berlin thus very far from his hometown. Stich also claimed 2 patents on mechanical foam control, described in this review, as well as 1 patent on molasses treatment, 1 on growth media (adjuncts), 1 on seeding conditions, and 2 on fermentation control with some link to aeration (Gélinas , ).…”

“…These are called “patent families.” Sometimes the same invention was described in patents filed in different countries and even granted to different applicants or inventors without reference to the priority file. Careful reading and comparison of patent specifications was essential to get a true picture of patenting activity over the years (Gélinas ). Such a large puzzle included about 560 individual patent specifications, mainly written in German, English, French, Danish, and, to a lesser extent, in Swedish, Dutch, and Finnish.…”

“…Number of patent applications on media, fermentation control, and aeration and foam control during the production of baker's yeast according to filing date (5 y range). Data on media and fermentation control were obtained from Gélinas (, ). Since the publication of the latter reviews, the following 8 patents were found and counted above, specifically on growth media (YU 57002 filed in 2002; KR 100522264 filed in 2005; US 20120128853 filed in 2010; RU 2010152223 filed in 2010; CN 102311927 filed in 2011; RU 2012138881 filed in 2012; CN 104087521 filed in 2014), and fermentation control (RO 127019 filed in 2012).…”