Gélinas Pierre
the Food Research and Development Centre, Agriculture and Agri-Food Canada, Saint-Hyacinthe, J2 8E3, Quebec, Canada.
Compr Rev Food Sci Food Saf. 2016 Mar;15(2):371-391. doi: 10.1111/1541-4337.12188. Epub 2016 Jan 11.
A key ingredient in the baking industry, baker's yeast must be produced under strict controlled conditions. High yields of baker's yeast cannot be attained unless a huge quantity of air is injected into fermentation vats. This review of 245 patent specifications shows that inventors have paid much attention to the distribution of fine air bubbles in order to optimize oxygen transfer to the yeast cells. Technical solutions to reduce energy costs associated with aeration are also proposed. Intense aeration caused foaming problems, so mechanical destruction of foam was first proposed until inventions on specific chemical antifoams were patented. In recent years, the development of cheaper and more efficient foam control techniques has remained an issue. Aeration during yeast growth in tanks impairs its fermentative activity in anaerobic bread dough. Since the beginning of the 20th century, massive adoption of air-grown fed-batch baker's yeast probably encouraged sugar addition to stimulate yeast gassing activity in pan bread characterized by high loaf volume, especially those prepared under short dough fermentation conditions.
面包酵母是烘焙行业的一种关键原料，必须在严格控制的条件下生产。除非向发酵罐中注入大量空气，否则无法获得高产的面包酵母。对245份专利说明书的审查表明，为了优化向酵母细胞的氧气转移，发明者们非常关注微小气泡的分布。还提出了降低与曝气相关的能源成本的技术解决方案。强烈曝气会导致泡沫问题，因此最初提出了机械消泡，直到关于特定化学消泡剂的发明获得专利。近年来，开发更便宜、更有效的泡沫控制技术仍然是一个问题。在罐中酵母生长期间曝气会损害其在厌氧面包面团中的发酵活性。自20世纪初以来，大量采用需氧补料分批培养的面包酵母可能促使人们添加糖分，以刺激酵母在具有高面包体积的烤盘面包中的产气活性，尤其是在短面团发酵条件下制备的面包。
