Abstract
This study assessed the influence of refrigerated, frozen and dried storage on technological performances and bacterial diversity of three type-I sourdoughs periodically reactivated.
Overall, the tested methods did not succeed to get reactivated sourdoughs with leavening capacity as high as that of unstored sourdoughs. On the contrary, all the sourdoughs maintained the acidification capacity when reactivated. DGGE profiles of the reactivated sourdoughs showed that acidification capacity could be attributed to only one of the starters used and, in one case, also to contaminant lactic acid bacteria. After 90 days of storage, one sourdough was chosen for a bread-making trial. Bread made from the sourdough reactivated after storage at −20 °C approached that made from unstored sourdough, in terms of hardness and crumb cell features.
This study showed that frozen storage enables until 90 days a partial preservation of the starter lactic acid bacteria and the obtainment of bread approaching that produced from unstored sourdough. Refrigeration and dried storage gave satisfactory results until 30 days of storage. After 60–90 days, no storage condition allowed to get reactivated sourdoughs with leavening capacity comparable to that of the unstored sourdough.