The effects of ultrasound on probiotic functionality: an updated review

AbstractThe effects of ultrasound (US) on probiotics, as health-promoting microbes, have attracted the attention of researchers in fermentation and healthy food production. This paper aims to review recent advances in the application of the US for enhancing probiotic cells’ activity, elaborate on the mechanisms involved, explain how probiotic-related industries can benefit from this emerging food processing technology, and discuss the perspective of this innovative approach. Data showed that US could enhance fermentation, which is increasingly used to enrich agri-food products with probiotics. Among the probiotics, recent studies focused on Lactiplantibacillus plantarum, Lactobacillus brevis, Lactococcus lactis, Lactobacillus casei, Leuconostoc mesenteroides, Bifidobacteria. These bacteria proliferated in the log phase when treated with US at relatively low-intensities. Also, this non-thermal technology increased extracellular enzymes, mainly β-galactosidase, and effectively extracted antioxidants and bioactive compounds such as phenolics, flavonoids, and anthocyanins. Accordingly, better functional and physicochemical properties of prebiotic-based foods (e.g., fermented dairy products) can be expected after ultrasonication at appropriate conditions. Besides, the US improved fermentation efficiency by reducing the production time, making probiotics more viable with lower lactose content, more oligosaccharide, and reduced unpleasant taste. Also, US can enhance the rheological characteristics of probiotic-based food by altering the acidity. Optimizing US settings is suggested to preserve probiotics viability to achieve high-quality food production and contribute to food nutrition improvement and sustainable food manufacturing.HIGHLIGHTSUltrasound affects probiotics during fermentation to produce healthy foodsUltrasound could enhance the activity of probiotic cells through various mechanismsLactobacillus plantarum, L. brevis, and Leuconostoc mesenteroides are most studied probioticsSonication could increase extracellular enzyme and antioxidant activity of fermented foodsKeywords: emerging technologiesultrasoundfermentationprobioticslactic acid bacteriafood processing Disclosure statementNo potential conflict of interest was reported by the authors.CRediT contributionThabani Sydney Manyatsi: Formal analysis, Investigation, Writing – original draft, Writing – review & editing; Amin Mousavi Khaneghah: Writing – review & editing; Mohsen Gavahian: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Resources, Software, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing.Additional informationFundingThe author(s) reported there is no funding associated with the work featured in this article.