Microbiological approaches for the implementation of algae in food: exploitation and safety evaluation

In order to guarantee food security for the future decades, food scientists are focusing their studies on the search for novel food sources with a low impact on the environment and that at the same time could represent a valuable source of nutrients. In these respects, seaweeds and microalgae have the right characteristics. Algae are a heterogeneous group of organisms characterized by the ability to perform photosynthesis. Algae are commonly divided into macro and microalgae. Macroalgae are eukaryotic pluricellular organisms while microalgae are unicellular prokaryotic or eukaryotic organisms. Given their composition, algae are an appropriate food source for consumers because they present low calories content and a high presence of nutrients such as essential amino acids, proteins, dietary fibers, vitamins, minerals and bioactive compounds. Their abundance in bioactive compounds confers to algae a great potential for food, nutraceutical and pharma industries. Several bioactivities have been accredited to algae: antimicrobial, antioxidant, antidiabetic, anti-inflammatory and immunomodulation action, and the use as functional ingredients of these organisms for the development of therapeutic agents is widely studied. For those reasons, greater employment of microalgae and seaweeds in food production could be a possible solution to guarantee food security for the next decades. Considering this premise and the great potential of this group of organisms, the aim of this thesis is to study three different aspects connected to the use of algae in food formulations. In particular, was studied the use of food-grade seaweed and microalgae extracts as natural preservatives in foods assessed through in vitro and in situ tests. An overview of food safety aspects connected to the use of algae in food was reported. Interactions of microalgae and lactic acid bacteria were evaluated in order to produce novel food productions or food supplements.