Delving into the bacterial diversity of spoiled green Manzanilla Spanish-style table olive fermentations.

This work applies metataxonomic, standard statistics, and compositional data (CoDa) techniques to study the bacterial diversity of spoiled and normal Spanish-style table olive fermentations, analysing a total of 10-tons of industrial fermentation containers from two processing yards. Forty percent were affected by butyric, sulfidic, or putrid spoilage, while 60% followed the ordinary fermentation course. The samples were obtained at 30 days of fermentation, determining their 16S rRNA gene Amplicon Sequence Variant compositions (ASVs). The butyric containers showed a bacterial profile strongly associated with the genera Enterococcus , Leuconostoc , and Atlantibacter , but also with Lactiplantibacillus and Melissococcus , and less confident to Raoultella , Enterobacter , Serratia , and Celerinatantimonas. The sulfidic fermentation was linked to Alkalibacterium and, to a lesser extent, Marinilactibacillus and the absence of Lactiplantibacillus. Putrid spoilage was mainly related to Halolactibacillus and Alkalibacterium. Sulfidic/putrid (together) differed from butyric spoilage by the presence of Alkalibacterium / Marinilactibacillus as well as by Halomonas / Halanaerobium. Lactiplantibacillus dominated normal fermentations, but Vibrio was also frequently found (0–46%), apparently not causing any alteration. These results contribute to a better microbial characterisation of non-zapatera spoiled table olive fermentations. They also suggest using several statistical techniques to discriminate normal vs spoiled fermentations adequately. • Bacterial profiles of spoiled industrial table olive fermentation vessels was studied. • Butyric spoilage was mainly related to Enterococcus , Leuconostoc , and Atlantibacter. • Sulfidic spoilage was primary associated with Alkalibacterium. • Putrid spoilage was linked to Halolactobacillus and Alkalibacterium. • Propionibacterium , Bacillus or Pseudomonas were not detected in the spoiled vessels. [ABSTRACT FROM AUTHOR]