Elena Bartkiene (Doctor of Physical Sciences, Chemistry) professor at Department of Food Safety and Quality, as well as Chief Researcher and Head of Institute of Animal Rearing Technologies in Lithuanian University of Health Sciences. Her scientific achievements comprise 435 positions, including 123 original research papers in journals cited in Clarivate Analytics data basis, 30 research papers in journals cited in other data basis, 4 book chapters, 128 reviewed conference theses, 5 textbooks for students’, 3 methodical books, 2 patents registered in EPO and 1 patent registered in Lithuanian national patent office etc. The research areas are basically in Food/Feed (Bio)Technology, Safety and Quality control, Molecular Microbiology, Sustainable (bio)Technology. She participated and have experience in coordinating and carrying out research projects (leader and/or participant in more than 23 national and international projects). She is scientific expert of the Lithuanian and Polish Agencies of Sciences, Reviewer and Editor of the national and international scientific journals; Member of the of ISEKI-Food Association (Austria) and Institute of Food Technologists (IFT, USA) organizations.
BERRIES / FRUITS, CEREAL, AND DAIRY INDUSTRY BY-PRODUCTS VALORIZATION BY USING LACTIC ACID BACTERIA STRAINS WITH ANTIMICROBIAL PROPERTIES
Elena Bartkiene, Modestas Ruzauskas, Egle Zokaityte, Vita Lele, Vytaute Starkute, Paulina Zavistanaviciute, Dovile Klupsaite, Laurynas Vadopalas, Darius Cernauskas, Vadims Bartkevics, Iveta Pugajeva, Zane Bērziņa, Romas Gruzauskas, Daiva Zadeike, Pranas Viskelis, Erika Mozuriene, Grazina Juodeikiene
By-products from berries/fruits (B/F), cereal, and dairy industry, are an important environmental issue in many countries. Most agro-industrial by-products contain highly valuable components, which are not used efficiently enough. One way to recover these, is the extraction of valuable compounds. However, in most of the cases, solvent extraction is not economically or/and involves the use of toxic extractants that hinder their management. As well as extraction involves high temperatures, which lead to degradation of thermolabile compounds. From this point of view, the use of technologies that enable valorization of the whole by-product can be a promising way to increase the efficiency and sustainability of the process. In our research group the concept of the valorization of B/F (raspberries, blackcurrants, apples, rowanberries) and dairy industry (sour whey) by-products, in combination with antimicrobial lactic acid bacteria (LAB) strains, for the preparation of antimicrobial combinations was analysed. Also, a design of extrusion and fermentation with L. casei and L. paracasei strains technologies combination for wheat processing by-products (WPBP) valorization to higher value food/feed stock was tested. Antimicrobial activities of the B/F by-products and LAB (thirteen LAB strains were estimated against fifteen pathogenic strains) were evaluated, while whey substrate for the selected and the highest antimicrobial activities showing LAB cultivation and encapsulation was used. In case to select the most appropriate technology for WPBP valorization, various parameters of the processed and nontreated WPBP were analysed: acidity and microbiological parameters, sugars concentration, free amino and fatty acids profile, biogenic amines formation, influence of the different treatments on WPBP texture and colour coordinates, antimicrobial and antifungal characteristics, as well as influence of the different treatments on a wide range of mycotoxins concentration.
It was found that lyophilised blackcurrant and apple by-products inhibited 13 and 12 pathogenic strains of the 15 analysed, respectively. The broadest antimicrobial spectrum and the strongest inhibition of the tested pathogens were shown by the Lactobacillus casei LUHS210 and Lactobacillus uvarum LUHS245 strains and, for the abovementioned LAB strains biomass preparation and encapsulation, whey enriched with 2.5% glucose, 2.0% yeast extract and 0.5% saccharose is a suitable and sustainable substrate. Moreover, the B/F by-products’ antimicrobial activity can be enhanced in combination with the LUHS245 and LUHS210 strains. Finaly, it was stated that B/F and dairy industry by-products, in combination with antimicrobial LAB are promising ingredients for the preparation of antimicrobial combinations. Also, it was confirmed that combination of extrusion and fermentation with L. casei and L. paracasei strains could be used as a perspective innovative pre-treatment for WPBP, capable to potentially enhance its composition, safety characteristics, antimicrobial and antifungal properties.
Keywords: food processing industry by-products; lactic acid bacteria; antimicrobial activity; antifungal activity; extrusion; fermentation; mycotoxins; biosafety.