Lactobacillus amylovorus LA 19280 as novel food-grade antifungal agent for bakery products

Mould spoilage is the main cause of substantial economic loss in bakery industry and might also cause public health problems due to the production of mycotoxins. The reduction of mould growth in bakery products is thus of crucial importance and there is great interest to develop safe and efficient strategies for this purpose. In this study Lactobacillus amylovorus LA19280 has been shown to produce a wide spectrum of antifungal compounds active against common bread spoilage fungi. Among the indicator moulds, Aspergillus fumigatus and Fusarium culmorum were the most sensitive organisms. Several antifungal compounds were found to be present in liquid medium inoculated with L. amylovorus LA19280 strain, some of them being reported here for the first time. Wheat doughs fermented with L. amylovorus LA19280 had good rheological properties and the breads thereof were of high quality as shown by rheofermentometer and texture analyzer measurements. The results were compared with those obtained using the non-antifungal L. amylovorus DSM20531T strain, a non-acidified and a chemically acidified dough. The quality of sourdough and bread started with L. amylovorus LA19280 was comparable to that obtained by using L. amylovorus DSM20531 T. Breads were evaluated for the ability to retard the growth of Fusarium culmorum FST 4.05, Aspergillus niger FST4.21, Penicillium expansum FST 4.22, Penicillium roqueforti FST 4.11 and fungal flora from the bakery environment. Bread started with strain L. amylovorus LA19280 showed a remarkable antifungal activity in both “in vivo” tests indicating that it could be used as novel biocontrol strategy for bakery products.