Shifts in ovine (Ovis aries) bulk-tank milk microbiota as a function of cold-storage temperature and duration

Abstract

The aim of this study was to identify the microbiota of ovine bulk-tank milk (BTM) and monitor its changes during storage at 4 °C or 8 °C for 2 or 4 days, simulating BTM holding times at the farm and/or the processing facility prior to milk processing, by using high-throughput sequencing of the 16S rRNA gene. The results showed that the microbiota is comprised of a plethora of taxa present in low abundance. The core microbiota consists of 28 bacterial genera with Staphylococcus being the most abundant at the time of sampling. Pseudomonas spp. exhibited the highest mean relative abundance at the end of all storage schemes, except for 2 days of storage at 4 °C. Sheep milk can be stored at 4 °C for 2 days without compromise in its microbiological quality, whereas milk storage at 8 °C for 2 days was almost equivalent to storage at 4 °C for 4 days.