Evaluating the Dynamics of Fermentation Conditions of Lacto-fermented Sauerkraut Produced with Various Food Safety Process Parameters

• Salt 1.6–3.2% reduced pH < 4.60 the fastest, ensuring pathogen control. • Starter culture accelerates pH drop by day 1 and improves consistency. • Fermentation at 30 °C was faster but caused yield loss; 22 °C was more stable. • Combining optimal parameters enhanced LAB growth and acid production for safety. Lacto-fermented foods such as sauerkraut have risen in marketing potential for local food processors; however, safety process parameters and established critical limits that validate process controls during production are limited. This study investigated process parameters such as vessel type (glass and plastic jars), salt concentration (0.0, 1.6, 2.4, 3.2, and 6.4%), use of starter culture, altered starting pH using lactic acid and acetic acid (to pH 5.50-5.00), and incubation temperature (22 °C or 30 °C) that may affect the fermentation conditions of sauerkraut over time. Samples prepared with 1.6, 2.4, and 3.2% salt significantly lowered the pH below 4.60 by day 5 (4.55 ± 0.12), day 7 (4.60 ± 0.11), and day 14 (4.45 ± 0.16), respectively, compared to other concentrations. LAB counts significantly increased by at least 8-log for 1.6 and 2.4% salt sauerkraut after day 1.5. The pH levels decreased significantly for sauerkraut samples inoculated with starter culture after day 1 (4.55 ± 0.23) compared to spontaneously fermented sauerkraut, in which pH decreased by day 2 (4.71 ± 0.44). Faster pH drop was observed for sauerkraut samples fermented at 30 °C than those at 22 °C, as well as higher LAB counts (2-3.5 log difference). Using sauerkraut as a model system, these findings demonstrate how key fermentation parameters influence pH decrease, LAB growth, and spoilage outcomes, and provide technical guidance for establishing process controls in lacto-fermented foods. Additional validation may be required for applying specific controls to other products.