Data from: Fermentation of the sugar kelp (Saccharina latissima) – exploring the potential of the kelp’s native microbiota as starter culture and the microbiological food safety of fermented products

This study investigated the use of native microbiota from the sugar kelp
Saccharina latissima, in the form of fermented kelp fluid (FKF) from a
spontaneous anaerobic fermentation process, as a starter culture (SC) for
the fermentation of freshly harvested biomass of the same species. Rapid
(< 48 h) acidification (pH < 4.3) was achieved for S.
latissima inoculated with FKF, at a fermentation temperature of 21 °C.
Kelp inoculated with a commercial strain of Lactiplantibacillus plantarum
(Lp, positive control) reached a similar pH level after 5 days, while kelp
with no SC (negative control) did not reach a pH level below 4.3 within
nine days. The microbiota of the FKF-SC as well as the FKF-inoculated S.
latissima samples was dominated by lactic acid bacteria (LAB) identified
as L. plantarum. The SC in these samples successfully converted mannitol
into lactic acid as the main fermentation product. In contrast, a higher
production of acetic acid and ethanol was measured in the negative control
samples compared to other groups reflecting a different microbial profile
including marine bacteria which could not be identified by MALDI-TOF
biotyping. Challenge trials of S. latissima samples from experimental and
commercial fermentation processes with Bacillus cereus did not result in
the growth of this food pathogen, even at pH levels within viable range
for this species (pH > 4.3). These preliminary results provide a
foundation for further isolation of suitable SCs for kelp fermentation in
commercial production and for assessing the food safety of fermented kelp.