Phenols extract from olive vegetation water (PEOW) as ingredient in raw sausages and salami

The phenols extract from olive vegetation water (PEOW) possess antioxidant activities and may be used in food industry as natural preservative. In vitro studies highlighted the bactericidal activities of PEOW against several food-borne strains. However the overall evaluation of their impact in real food models is the first step to determine their feasibility as ingredient. This study describes the effects of PEOW on the microbial populations of raw sausages and fermented salami. Raw sausages were produced according to local recipe to obtain a control batch and two batches with different levels of PEOW addition (75 mg/100 g: LL - Low Level and 150mg/100 g: HL High Level). PEOW levels were based on sensory and antibacterial tests. Changes of microbial composition were assessed during a storage period of 12 days (4 °C) by the following targets: mesophilic and psycrotrophic count, lactic acid bacteria (LAB), Staphylococcus spp., Pseudomonas spp., yeasts and moulds count. The identification of the most representatives strains were based on 16S rRNA or ITS/26S rRNA gene sequencing. Similar practices were adopted for the salami production using Staphylococcus xylosus and Pediococcus pentosaceus as starters cultures. The salami were evaluated for LAB, Staphylococcus spp., yeasts and moulds during ripening period of 20 days. In sausages, the HL inclusion of PEOW reduced the growth of several microbial targets especially Staphylococcus spp., while yeasts increased. The Permutational multivariate analysis of variance and the Principal coordinate analysis suggested a clear distinction of the PEOW added sausages. The effect of phenols used as ingredient in salami also showed a relevant impact in the S. xylosus during the first part of ripening period. These results highlighted the potential modulation of microbial populations on raw and fermented meat products, that needs to be considered for the manufacturing practices.