Structural, thermal, morphological, and rheological properties of yeast extracts obtained from Saccharomyces cerevisiae, Saccharomyces boulardii, and Kluyveromyces marxianus

Yeast extracts, which are mostly used as flavor enhancers in foods, also give to the nutritional value of foods, especially due to their amino acid profiles. In addition to all these properties, yeast extracts have the possibility to supply added technological advantages to the foods they are used in due to their physicochemical properties. However, there are not enough studies investigating the structural, thermal, morphological, and rheological properties of yeast extract powders. To fill this gap and investigate the potential of yeast extracts to supply added benefits to foods, in this study, yeast extract powders obtained from Saccharomyces cerevisiae TGM10, Saccharomyces boulardii S11, and Kluyveromyces marxianus TGM66 structural properties were investigated using Fourier Transform Infrared Spectroscopy, thermal properties using Differential Scanning Calorimetry, morphological properties using Scanning Electron Microscopy and rheological properties using rheometer. The melting points of Saccharomyces cerevisiae TGM10, Saccharomyces boulardii S11, and Kluyveromyces marxianus TGM66 extracts were 129 °C, 128 °C and 132 °C, respectively. It is believed that the Fourier Transform Infrared spectra obtained in the study will contribute to the literature in terms of the production and identification of yeast extracts, and the morphological properties will contribute to the determination of the drying method to be applied to the extracts. It was determined that all three yeast extracts used in the study had the potential to increase the viscosity of the soup, and the yeast extract obtained from Kluyveromyces marxianus TGM66 was the most successful sample in this respect. It is thought that this may be related to the fact that this extract has a different carbohydrate and/or amino acid profile than others. Considering the data obtained in the study, it is thought that with a better understanding of the structural, thermal, morphological, and rheological properties of yeast extracts, the possibility of using these additives in foods will expand.