Potential Use of Silica Nanoparticles for the Microbial Stabilisation of Wine: An In Vitro Study Using <i>Oenococcus oeni</i> as a Model

• Published in: Foods
• Main Authors: Kamila Pachnowska, Krzysztof Cendrowski, Xymena Stachurska, Paweł Nawrotek, Adrian Augustyniak, Ewa Mijowska
• Format: Article
• Language: English
• Published: MDPI AG 2020-09-01
• Subjects: silica nanospheres; antibacterial agents; stirring; <i>Oenococcus oeni</i>; process stabilisation
• Online Access: https://www.mdpi.com/2304-8158/9/9/1338

The emerging trend towards the reduction of SO₂ in winemaking has created a need to look for alternative methods to ensure the protection of wine against the growth of undesired species of microorganisms and to safely remove wine microorganisms. This study describes the possible application of silica nanospheres as a wine stabilisation agent, with <i>Oenococcus oeni</i> (DSM7008) as a model strain. The experiment was conducted firstly on model solutions of phosphate-buffered saline and 1% glucose. Their neutralising effect was tested under stirring with the addition of SiO₂ (0.1, 0.25, and 0.5 mg/mL). Overall, the highest concentration of nanospheres under continuous stirring resulted in the greatest decrease in cell counts. Transmission electron microscope (TEM) and scanning electron microscopy (SEM) analyses showed extensive damage to the bacterial cells after stirring with silica nanomaterials. Then, the neutralising effect of 0.5 mg/mL SiO₂ was tested in young red wine under stirring, where cell counts were reduced by over 50%. The obtained results suggest that silica nanospheres can serve as an alternative way to reduce or substitute the use of sulphur dioxide in the microbial stabilisation of wine. In addition, further aspects of following investigations should focus on the protection against enzymatic and chemical oxidation of wine.