Determination of Lactic Acid Bacterial Numbers of Lyophilized or Frozen Natural Lactic Acid Bacterial Liquids Prepared with Different Methods and Stored for Different Times

Authors : Sadık Serkan Aydın, Nihat Denek

Pages : 29-41

Doi:10.30607/kvj.1288653

View : 62 | Download : 63

Publication Date : 2024-03-31

Article Type : Research Paper

Abstract :In this study, it was aimed to determine the lactic acid bacterium (LAB) counts and viability of fermented lactic acid bacteria liquids (pre-fermented juice (PFJ)) prepared with different levels of sucrose (3%, 5% and 10%) addition and incubation at different times (2, 5 and 10 days), using different cryoprotectants (trisodiumcitrate (TRIS) and dimethylsulfoxide (DMSO)), freezing and lyophilization, and at the end of different storage periods (one and three months). In frozen PFJs, the highest LAB counts were obtained in the TRIS and 5% sucrose supplemented group incubated for 5 days in a one-month storage period, and in the TRIS and 10% sucrose supplemented group incubated for 5 days at the end of the three-month storage period (p<0.01). At the end of one month of storage, the highest LAB numbers in lyophilized PFJs were obtained in groups incubated for 5 days and supplemented with 10% sucrose with TRIS and DMSO. In lyophilized PFJs subjected to 3-month storage, the highest LAB numbers were determined in the TRIS and 5%-10% sucrose-supplemented groups incubated for 5 days and in the DMSO and 5% sucrose-supplemented group incubated for 2 days (p<0.01). When the results obtained in the study were evaluated in general, it was observed that the viability ratios of LAB decreased due to the sucrose level and the prolongation of incubation and storage time. It can be said that cryoprotectant additive has a positive effect on the preservation of LAB and lyophilization process is advantageous compared to freezing in the deep freezer.
Keywords : Dondurulma, Laktik asit bakterisi, Liyofilizasyon