Changes in viable cell counts and functional properties of lactic acid bacteria products under simulated marine shipping conditions

This study examined changes in viable cell counts and functional efficacy (anti-inflammatory effects) of lactic acid bacteria (LAB) products (in pouch and stick forms) based on storage period and loading positions (outer-deck, on-deck, and under-deck) in a simulated marine shipping environment. Viable cell counts of pouch products, measured on days 1, 7, 14, and 21, showed a greater decrease under the outer-deck condition (13.5, 11.1, 7.5, and 8.0 log CFU/g) compared to the on-deck and under-deck conditions. Stick products also experienced significant reductions over time, with values of 12.0, 4.1, 3.2, and 2.1 log CFU/g under the outer-deck condition. The anti-inflammatory effect was evaluated through nitric oxide production, and the pouch product showed production of 34.4%, 57.7%, and 62.1% on days 1, 11, and 21, respectively, while the stick product showed production of 45.3%, 88.2%, and 90.5%. Cytokine production assays confirmed a decline in anti-inflammatory effects for products stored under outer-deck conditions. These results suggest that the viable cell counts and efficacy of LAB products are significantly impacted by storage position during marine shipping, particularly under outer-deck storage. Optimized storage and transportation strategies are necessary to maintain viability and functional efficacy, thereby enhancing product quality and consumer trust.