Zinc Tolerance of Special Yeasts and Lactic Acid Bacteria for Use in the Food Industry
Samantha Rossi,
Maria Maares,
Helena Kieserling,
Sascha Rohn,
Oliver Schlüter,
Francesca Patrignani,
Rosalba Lanciotti,
Hajo Haase,
Claudia Keil
Affiliations
Samantha Rossi
Campus Food Science, Department of Agricultural and Food Sciences, Alma Mater Studiorum, University of Bologna, p.zza Goidanich 60, 47521 Cesena, Italy
Maria Maares
Department of Food Chemistry and Toxicology, Institute of Food Technology and Food Chemistry, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
Helena Kieserling
Department of Food Chemistry and Analysis, Institute of Food Technology and Food Chemistry, Technische Universität Berlin, Straße des 17. Juni 135l, 10623 Berlin, Germany
Sascha Rohn
Department of Food Chemistry and Analysis, Institute of Food Technology and Food Chemistry, Technische Universität Berlin, Straße des 17. Juni 135l, 10623 Berlin, Germany
Oliver Schlüter
Leibniz Institute for Agricultural Engineering and Bioeconomy, Quality and Safety of Food and Feed, 14469 Potsdam, Germany
Francesca Patrignani
Campus Food Science, Department of Agricultural and Food Sciences, Alma Mater Studiorum, University of Bologna, p.zza Goidanich 60, 47521 Cesena, Italy
Rosalba Lanciotti
Campus Food Science, Department of Agricultural and Food Sciences, Alma Mater Studiorum, University of Bologna, p.zza Goidanich 60, 47521 Cesena, Italy
Hajo Haase
Department of Food Chemistry and Toxicology, Institute of Food Technology and Food Chemistry, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
Claudia Keil
Department of Food Chemistry and Toxicology, Institute of Food Technology and Food Chemistry, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
In order to address human zinc deficiency, fortifying staple foods with zinc is a safe and cost-effective solution. To ensure the nutritional properties and quality of a final product, zinc tolerance of the microorganisms involved in the fermentation is necessary. Bread, which is widely consumed, occupies a substantial place in many people’s diets, and is often based on a sourdough making process; thus, it might be an important headlining product. This study investigated the zinc tolerance of yeasts and lactic acid bacteria that are specifically suited to produce sourdough bread made with cricket powder hydrolysate and wheat flour. Amongst the yeasts, Kazachstania servazzii KAZ2 and Kazachstania unispora FM2 were only slightly affected in regard to cell growth and colony-forming ability when cultured in YPD broth spiked with 0.5 or 1 mM ZnSO4, respectively. Yarrowia lipolytica RO25 showed a higher tolerance for up to 2.5 mM zinc (ZnSO4). All the yeast strains were capable of accumulating zinc in the range between 200 and 400 fg/cell. The heterofermentative lactic acid bacterium Fructilactobacillus sanfranciscensis DG1 appeared to have a moderate zinc requirement and was homeostatically balanced, even under a high 20 mM extracellular ZnSO4 load. A better understanding of zinc homeostasis in yeast and lactic acid bacteria for food industry applications may lead to improvements in zinc fortification, which might contribute to diminishing Zn deficiencies, especially in vulnerable population groups.
