** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** BREAD IS A STAPLE FOOD PRODUCT WORLDWIDE, BUT CURRENT BREAD MANUFACTURING PRACTICES FALL SHORT IN ADDRESSING CONSUMER DEMANDS FOR CLEAN LABEL PRODUCTS THAT SATISFY DIETARY REQUIREMENTS LIKE GLUTEN-FREE. THIS HAS LED TO BREAD BEING THE GREATEST CONTRIBUTOR TO FOOD WASTE WORLDWIDE. INCREASING GLOBAL POPULATION AND INCREASING PREVALENCE OF GLUTEN INTOLERANCES SUCH AS CELIAC DISEASE DEMAND A SUSTAINABLE SOLUTION FOR PRODUCING STAPLE FOOD ITEMS THAT SATISFY CONSUMERS IN TERMS OF QUALITY AND SAFETY. SOURDOUGH FERMENTATION IS AN ANCIENT BREADMAKING PRACTICE THAT IS STILL POPULAR TODAY AND IS TYPICALLY ASSOCIATED WITH ARTISANAL BREAD PRODUCTION. THE POPULATIONS OF MICROORGANISMS THAT FUNCTION TO LEAVEN SOURDOUGH BREAD, KNOWN AS STARTER CULTURES, ARE UNIQUE IN TERMS OF MICROBIAL COMPOSITION (I.E., WHAT BACTERIA AND YEAST THEY CONTAIN) AND IN TERMS OF FUNCTION (I.E., WHAT THOSE BACTERIA AND YEAST CAN DO OVER THE COURSE OF FERMENTATION). EXISTING EVIDENCE SUPPORTS THE IDEA THAT SOME MICROORGANISMS FOUND IN SOURDOUGH STARTER CULTURES CAN CONTRIBUTE TO BENEFICIAL CHARACTERISTICS IN BREAD INCLUDING SUPERIOR FLAVOR/AROMA, EXTENDED SHELF LIFE AND EVEN REDUCED GLUTEN CONTENT. HOWEVER, THE PRECISE RELATIONSHIP BETWEEN MICROBIAL POPULATIONS AND THEIR FUNCTIONS ARE NOT WELL UNDERSTOOD DUE TO THE COMPLEXITY AND DIVERSITY OF UNIQUE STARTER CULTURES, SO IT IS CURRENTLY IMPOSSIBLE TO EITHER PREDICT HOW A BREAD PRODUCT MIGHT TURN OUT BASED ON ITS STARTER CULTURE OR TO SELECT FOR SPECIFIC CHARACTERISTICS OF A BREAD BY USING A CERTAIN SOURDOUGH STARTER.THE PRIMARY GOAL OF THIS PROJECT IS TO UNDERSTAND THE RELATIONSHIP BETWEEN THE MICROBIAL POPULATIONS OF SOURDOUGH STARTER CULTURES AND THEIR FUNCTIONS OVER THE COURSE OF BREADMAKING. WE WILL DO THIS BY CHARACTERIZING THE GENETIC SEQUENCES OF THE BACTERIA AND YEASTS IN 20 UNIQUE STARTER CULTURES AND MEASURING THEIR SPECIFIC FUNCTIONAL ABILITIES RELATED TO (1) BREAD SHELF-LIFE AND STABILITY AND (2) GLUTEN BREAKDOWN AND THE PREVENTION OF CELIAC DISEASE-ASSOCIATED INFLAMMATION IN VITRO. IN A SERIES OF EXPERIMENTS, WE WILL MONITOR BREAD SHELF LIFE PRODUCED BY THESE STARTERS BY MEASURING MOLD GROWTH AND STALING OVER TIME. TO ASSESS THE EFFECT OF GLUTEN FROM THESE BREADS ON CELIAC DISEASE SYMPTOMS, WE WILL USE AN IN VITRO MODEL OF THE SMALL INTESTINE TO MEASURE INFLAMMATION AND INTESTINAL PERMEABILITY (I.E. LEAKY GUT). WE WILL ALSO INVESTIGATE WHETHER THESE FUNCTIONAL ABILITIES ARE CONSERVED OVER TIME AND USE OF EACH STARTER CULTURE IN ORDER TO UNDERSTAND HOW CULTURES WITH THESE SPECIFIC BENEFICIAL FUNCTIONS COULD BE USED IN A TYPICAL FOOD PROCESSING SCENARIO. BY UNDERSTANDING THE SPECIFIC MICROBIAL PROFILES AND RELATIONSHIPS THAT DRIVE FUNCTIONAL OUTCOMES IN FOOD PROCESSING, WE WILL BE ABLE TO SELECT FOR AND TUNE CULTURES TO MEET FOOD PROCESSING NEEDS. THE ULTIMATE GOAL OF THIS PROJECT IS TO DEVELOP TARGETED FERMENTATION APPROACHES FOR FOOD PRODUCTION, WHERE CHEMICAL ADDITIVES AND UNSUSTAINABLE PROCESSES CAN BE REPLACED BY POPULAT,IONS OF MICROORGANISMS ABLE TO ELICIT THE SAME EFFECTS WHILE PRODUCING HIGH-QUALITY FOOD PRODUCTS. THIS HAS THE POTENTIAL TO BENEFIT SOCIETY BY PROVIDING SUSTAINABLE OPTIONS FOR MEETING CONSUMER DEMANDS FOR CLEAN LABEL, HIGH QUALITY FOOD PRODUCTS.