Lactic acid bacteria (LAB) are capable of synthesising metabolites known as exopolysaccharides (EPS) during fermentation. Traditionally, EPS plays an important role in fermented dairy products through their gelling and thickening properties, but they can also be beneficial to human health. This bioactivity has gained attention in applications for functional foods, which leads them to have prebiotic, immunomodulatory, antioxidant, anti-tumour, cholesterol-lowering and anti-obesity activity. Understanding the parameters and conditions is crucial to optimising the EPS yields from LAB for applications in the food industry. This review provides an overview of the functional food market together with the biosynthesis of EPS. Factors influencing the production of EPS as well as methods for isolation, characterisation and quantification are reviewed. Finally, the health benefits associated with EPS are discussed.

Lactobacillus rhamnosus (L. rhamnosus) is a commensal bacterium with health-promoting properties and with a wide range of applications within the food industry. To improve and optimize the control of L. rhamnosus biomass production in batch and fed-batch bioprocesses, this study proposes the application of artificial neural network (ANN) modelling to improve process control and monitoring, with potential future implementation as a basis for a digital twin.

Lactic acid bacteria are traditionally applied in a variety of fermented food products, and they have the ability to produce a wide range of bioactive ingredients during fermentation, including vitamins, bacteriocins, bioactive peptides, and bioactive compounds. The bioactivity and health benefits associated with these ingredients have garnered interest in applications in the functional dairy market and have relevance both as components produced in situ and as functional additives. This review provides a brief description of the regulations regarding the functional food market in the European Union, as well as an overview of some of the functional dairy products currently available in the Irish and European markets. A better understanding of the production of these ingredients excreted by lactic acid bacteria can further drive the development and innovation of the continuously growing functional food market.

Lactic acid bacteria are traditionally applied in a variety of fermented food products and have the capability to produce a wide range of bioactive ingredients during fermentation including vitamins, bacteriocins, bioactive peptides and bioactive compounds. The bioactivity and health benefits associated with these ingredients have gained interest in applications in the functional dairy market and have relevance both as components produced in situ and as functional additives. This review provides a brief description of the regulations regarding the functional food market in the European Union as well as an overview of some of the functional dairy products currently available in the Irish and European markets. A better understanding of the production of these ingredients excreted by lactic acid bacteria can further drive the development and innovation of the continuously growing functional food market.

An artificial neural network (ANN)-based digital twin feed controller, aiming to optimise bioprocess performance, was implemented in fed-batch bioprocesses of Lactobacillus rhamnosus LRH30 for the production of biomass. The online data from several fed-batch bioprocesses in dairy-based cultivations with L. rhamnosus were utilised to develop an ANN that predicts the biomass and growth rate of L. rhamnosus in the process. This growth rate estimator was first validated through unit testing before being applied in model predictive control to select the best control action to drive feed addition to the process. The controller was implemented in fed-batch bioprocesses and the growth rate was estimated in real time, leading to the highest cell dry weight biomass concentrations obtained for L. rhamnosus LRH30 of 36.23 g/L in this study, with growth-rate overshoot and increased feed addition also contributing to the biomass accumulation despite imperfect setpoint tracking. The dose-dependent effect of L. rhamnosus LRH30 samples on cytokine secretion from murine macrophages was further explored, and an anti-inflammatory effect was found at a dosage of 10 mg/mL of bacterial cell dry weight. These experiments demonstrate the first steps in the implementation phase that will ultimately lead to a better controlled bioprocess with higher yields of L. rhamnosus biomass. Future research will focus on the continuous development of the ANN through the incorporation of more datasets, while simultaneously exploring the functional potential of L. rhamnosus LRH30.