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In the 19th century, bread had a pronounced acidic taste and a nonuniform appearance, as shown by a review of 178 early patents families on baker's yeast manufacture. This was largely due to the unpredictable nature of baker's yeast, which was generally grown under empiric conditions in nonsterile dough or liquid prepared with saccharified cereals. Inventors were mainly interested in techniques to increase yields of pressed yeast through media formulation, infection control, and automation of biomass separation and packaging. Still in its infancy, baker's yeast technology was slow to develop and apply new ideas due to lack of awareness on information published in patents and the scientific literature. This review also gives background information on early patents.

The effect of the composition and physical properties of bran from four wheat samples from different cultivars was determined in whole wheat bread. High specific volume of whole wheat bread was correlated (r 2 = 0.8275) with strong mechanical properties (low friability) of the bran of wheat cultivars, as determined by sizing (over 425 lm) of bran particles after grinding with a rotor mill. Fibre content and composition of insoluble fibre (hemicellulose, cellulose and lignin) in the bran fraction had a non-significant (P > 0.05) effect on the performance of wheat cultivars in whole wheat bread. Water absorption of bran was correlated (r 2 = 0.9532) with its insoluble fibre content.

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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.

The use of surfactant solutions for the in situ recovery of residual NAPL in aquifers is increasingly considered as a viable remediation technique. The injection of a few pore volumes of high concentration surfactant solutions can mobilize most of the residual NAPL contacted by the solutions. However, the washing solutions’physico‐chemical properties (low density and high viscosity), combined with the natural porous media heterogeneity, can prevent a good sweep of the entire contaminated volume. From the petroleum industry, it is well‐known that polymer solutions can be injected following a surfactant solution slug to act as a mobility buffer and increase the overall sweep efficiency. The objective of our laboratory study is first to select and characterize polymers that would be suitable for aquifer restoration. Our experiments showed that among several polymers, xanthan gum solution rheology was made in order to predict shear rates, xanthan gum concentrations, salinity, and temperature effects on solution viscosity. The second set of experiments were made with a sand box which was designed to reproduce a simple heterogeneous media consisting of layers of sand with different permeability. These tests illustrate the xanthan gum solution's ability to increase surfactant solution's sweep efficiency and limit viscous fingering. The tests established that: (1) the injection of xanthan solution behind a surfactant solution slug decreases fluid velocity in high permeability layers and increases it in low‐permeability ones, thus increasing the sweep efficiency (2) xanthan solutions eliminate viscous fingering at the polymer/surfactant solution front; (3) a xanthan solution preflush is desirable to limit surfactant solution mobility and prevent surfactant adsorption on solids; and (4) depending on site heterogeneity injection strategies should be applied to limit overriding by low‐density surfactant solution.