Two　different　sourdoughs,　named　SLB02012　and　SL20998,　were　prepared　respectively　with　Lactobacillus　plantarum　B02012　andLactobacillus　alimentarius　20998,　having　similar　acid　production　rate　and　acidification　performance　in　this　study.　Also,　sourdoughs　SYLB02012　and　SYL20998　were　made　with　each　of　the　two　strains　in　combined　with　yeast,　respectively.Traditional　yeast-fermented　sourdough　(SY)　and　non-fermented　sourdough　made　with　edible　organic　acids　(SCA)　as　well　as　non-inoculated　dough　with　erythromycin　(CK)　were　used　as　controls.　Gliadin　was　extracted　from　each　sourdough　and　was　evaluated　for　secondary　and　tertiary　structures　and　immunoreactivity　by　sodium　dodecyl　sulfate-polyacrylamide　gel　electrophoresis　(SDS-PAGE),　Fourier　transform　infrared　spectroscopy　(FTIR),　intrinsic　fluorescence　spectroscopy　(IFS),　enzyme　linked　immunosorbent　assay　(ELISA),　and　their　correlation　were　analyzed　by　agglomerative　hierarchical　clustering(AHC).　SDS-PAGE　results　indicated　that　protein　hydrolysis　in　dough　was　mainly　governed　by　lactic　acid　bacteria.　Highmolecular-mass　glutenin　(HMM-GS)　and　some　gliadins　in　SLB02012　were　more　effectively　degraded　than　in　SL20998.　Further,　FTIR　and　IFS　analyses　indicated　that　the　molecular　flexibility　of　glutens　in　SLB02012　increased.　Moreover,　SLB02012　exhibited　the　most　marked　decrease　inα-helix　content　and　the　smallestα-helix/β-sheet　content　ratio　among　the　7　doughs.　In　addition,　SY,　SLB02012　and　SYLB02012　showed　blue　shifts　of　λmax,　while　SL20998　showed　a　red　shift　of　λmax,　implying　that　the　tertiary　structure　of　the　proteins　was　extended.　In　terms　of　the　immunoreactivity　of　gliadins　as　measured　by　ELISA,　SLB02012　showed　a　decrease　of　35%　compared　with　CK,　while　no　significant　difference　was　noted　for　SCA　and　SL20998　increased　by　29.5%.AHC　showed　a　good　correlation　between　the　secondary　and　tertiary　structures　and　the　immunoreactiviity　of　gliadins　for　each　of　these　sourdoughs.　Taken　together,　Lactobacillus　plantarum　B02012　can　be　used　as　a　dominant　bacterium　in　low　allergenic　fermented　foods,　and　this　study　provides　theoretical　support　for　understanding　the　mechanism　of　action　of　lactic　acid　bacteria　in　reducing　allergenicity.　©　2019,　China　Food　Publishing　Company.　All　right　reserved.