Comparison of biopreservatives obtained from a starter culture of Pediococcus acidilactici by different techniques

Due to the increase by consumers of healthy products, the exploration of natural antimicrobial compounds has been promoted through the use of by-products of lactic acid bacteria. Therefore, the aim of this research was to obtain an antimicrobial powder (cell free) by freeze-drying (FD) and spray-drying (SD) from the microbial stabilisation (filtration or partial purification) of a Pediococcus acidilactici fermentation broths. The antimicrobial activity of these powders was quantified, in vitro, against Listeria innocua CECT 4032 as a target microorganism. The physicochemical properties tested on these powders were water content, hygroscopicity, water activity, porosity, colour and solubility. As results, microbiological stabilisation is potentially better to perform a partial purification since the antimicrobial capacity against L. innocua CECT 4032 is higher than with filtration. On the other hand, SD is the best technique to obtain the powder, since it obtains a better productivity with a lower cost and also a more stable powder during storage.

Automated summary

This research aimed to obtain an antimicrobial powder from by-products of lactic acid bacteria and tested for its physicochemical properties and antimicrobial activity. The study found that microbial stabilisation and spray-drying are better techniques to obtain a more stable powder with higher productivity.