Selection of Debaryomyces hansenii isolates as starters in meat products based on phenotypic virulence factors, tolerance to abiotic stress conditions and aroma generation

Abstract

Introduction: Debaryomyces hansenii is a yeast widely used in meat fermentations as starter for the purpose of improving the aromatic quality of the final product.However, it has not been the subject of an extensive study regarding phenotypic characteristics important for starter selection, such as the capacity to grow at abiotic stress conditions occurring during fermentation, the ability to generate desirable aromas and the absence of virulence traits in yeasts. Aims:The aim of this study was to screen 60 strains of D. hansenii isolated from assorted foods for their potential application as starters in dry-cured fermented sausages manufacture. Methods:The abiotic stress factors tested were low a w and pH and high concentration of salt, acetic acid and lactic acid. The phenotypic virulence traits explored were growth at 37°C, pseudohyphal and biofilm generation, invasiveness and enzymatic activities present in virulent yeasts. The generation of desirable meat aromas was tested in models containing aroma precursors applying an olfactory analysis. A quantitative profiling of stress tolerance was used to test the potential performance of selected strains in meat fermentations. Results:The results demonstrated that most strains displayed no virulence trait or were only positive for biofilm production. Moreover, the strains showed large heterogeneity regarding their tolerance to abiotic stress factors, although most of them could grow at intermediate to high levels of the traits. The sensory analysis was the criteria determining the selection of starter strains. Conclusions:The evaluation of the phenotypic traits demonstrates that D. hansenii is a safe yeast, it is able to tolerate the stress in meat fermentation and it is able to generate desirable aromas. Significance and Impact of the Study:The results of this study confirm the adequacy of selected D. hansenii strains to be applied as starters in meat products.

Short-Term Changes in Aroma-Related Volatiles in Meat Model: Effect of Fat and D. hansenii Inoculation

“…TMB were not detected in the PLY and VOY models, although the inhibitory effect of D. hansenii on the growth of TMB had not been observed and requires further research. The absence of yeast after 28 d in the PLY and VOY models indicates the inhibition of yeast growth, probably due to a decrease in the pH of the meat model system at 28 d ( Figure S1 ) because low pH can inhibit the growth of D. hansenii [ 15 ]. Furthermore, the increase in pH was followed by a sustained decrease in the model, may be due to an increase in alkaline amino acids, followed by an increase in acidic amino acids and fatty acids ( Figure S1 ).…”

Fermentation of Texturized Pea Protein in Combination with Proteases for Aroma Development in Meat Analogues

“…The sensory analysis was performed from model samples at the end of the fermentation process (15 days) using the detection frequency method to reveal the aroma impact of volatile compounds in the models. Odors were evaluated by six trained panellists, four females and two males with an average of 40 years old, who evaluated the odors by smelling the model samples as reported by Belloch et al The aroma descriptors were recorded, and the results were expressed as the number of times a descriptor was detected by the panellists. , …”

Update of the list of qualified presumption of safety (QPS) recommended microbiological agents intentionally added to food or feed as notified to EFSA 17: suitability of taxonomic units notified to EFSA until September 2022

“…Belloch et al. ( 2022 ) screened 60 strains of D. hansenii from assorted foods for potential as starters in dry‐cured sausages and for physiological properties associated with virulence. Most strains were negative for all virulence traits, except that some were positive for biofilm production.…”