Enhancing Spanish Olives with the Microbial Alliance Lachancea thermotolerans and Lactiplantibacillus plantarum

Traditionally, Spanish-style table olive fermentation is driven by lactic acid bacteria (LAB) for acidity, preservation, and sensory profiles. Recently, there has been growing interest in using other microorganisms, especially yeasts, to improve fermentation. Lachancea thermotolerans, a yeast often isolated from wine fermentations, has metabolic properties beneficial for table olive fermentation. This study evaluated co-inoculating L. thermotolerans and Lactiplantibacillus plantarum on the fermentation dynamics and quality of Spanish-style table olives. Green olives were inoculated with pure cultures of L. thermotolerans and L. plantarum. Single inoculations and a spontaneous fermentation (control) were also included. All fermentations ran for 120 days at 20°C. L. thermotolerans appeared to stimulate LAB growth during the initial 20 days. Co-inoculation of L. thermotolerans and L. plantarum resulted in the highest organic acid concentrations, leading to a more pronounced pH decrease than that in the control. This combined inoculation improved key quality attributes like olive texture and colour and achieved the best tasting scores. Mixed starter cultures of L. thermotolerans and L. plantarum positively influence the fermentation dynamics and final quality of Spanish-style table olives. This represents a viable strategy for producing table olives with distinctive sensory and technological characteristics.