###### Abstract  
There is scarce data on the influence of fermentation with lactic acid bacteria (LAB) on the quality and safety of edible mushrooms. The aim of this study was to ferment _Sullus luteus_, _Boletus edulis_, _Cantharellus cibarius_, and _Rozites caperata_ with LAB strains (_Lacticaschucillus casei_ LUHS210 and _Liquorilactobacillus uavarum_ LUHS245) and to evaluate the influence of this technology on colour characteristics, pH, mould/yeast count, liking, emotional response, volatile compound (VC) profile, and the formation of biogenic amines (BA). Additionally, ultrasonication or prolonged thermal treatment were applied before fermentation. The LUHS245 strain showed better preservation properties in the case of fungal inhibition; however, prolonged thermal treatment and/or ultrasound pre-treatment ensure safer fermentation. Mushrooms species and type of pre-treatment had a significant effect on colour coordinates and pH (\(p\leq 0.0001\)). A greater variety of VC was identified in pre-treated and fermented samples. Significant differences were found between the emotions induced in consumers. The lowest sum of BA was found in thermally pre-treated and fermented _R. caperata_, while the highest was in ultrasonicated and fermented _B. edulis_. Finally, despite good overall acceptability, it is important to select appropriate LAB strains for the fermentation of edible mushrooms to ensure their safety in the case of BA formation. edible mushrooms; fermentation; lactic acid bacteria; volatile compounds; biogenic amines 1  
11800[[https://doi.org/10.3390/foods1112180019](https://doi.org/10.3390/foods1112180019)]([https://doi.org/10.3390/foods1112180019](https://doi.org/10.3390/foods1112180019)) May 202216 June 202216 June 202218 June 2  
agents, coating, and ozone), and physical (irradiation, plasma, packaging, and pulsed electrical field) preservation techniques, as well as long-term preservation (marinating with acetic acid, heavy salting, and freezing), significantly increase mushroom shelf-life, these methods have some limitations in maintaining mushroom quality and safety. [5; 6]. Furthermore, some of these preservation techniques may have drawbacks such as a high initial investment or a lengthy processing time. Until now, in many countries with different nutrition traditions, lactic acid fermentation has been traditionally applied to preserve both wild-grown and cultivated edible mushrooms [6]. Compared to the salting process of mushrooms, fermentation with lactic acid bacteria (LAB) requires a lower salt content and significantly lower losses of nutrients could be obtained [6]. Lactic acid fermentation is a natural, simple, and widely available method for food processing. This method is also advantageous from an economic point of view; however, it has not been applied on a large industrial scale for mushroom preservation [6; 7]. Microorganisms involved in the fermentation process belong to the group of LAB, which have a GRAS (Generally Recognised as Safe) status [8]. Moreover, the use of selected LAB strains with preservative characteristics provides beneficial properties for fermented foods: enrichment with vitamins, increased resistance to microbial spoilage, improved sensory characteristics, nutritional value, health-promoting effects, etc. [8; 9; 10; 11]. The _Lacticiseobacillus casei_ LUHS210 and _Liquorilactobacillus uarum_ LUHS245 used in this study were isolated from spontaneous rye sourdough and, as our previous studies showed, these LAB strains can be effective antimicrobial agents in food preservation [12]. However, despite the formation of desirable compounds during fermentation with LAB, non-desirable changes can also occur, i.e., the formation of biogenic amines (BA), the presence of which in foods is related to both food quality and safety [13]. In fermented foods, LAB, as well as other decarboxylase positive bacteria and yeasts, are able to produce BA through the decarboxylation of free amino acids [14; 15].