# Immobilized Lacticaseibacillus paracasei on Sunflower Seeds as a Stable Functional Ingredient for Cream Cheese

## TL;DR

This study shows that probiotic bacteria immobilized on sunflower seeds can survive better in cream cheese and during digestion compared to free cells.

## Contribution

A novel method of immobilizing probiotic L. paracasei on sunflower seeds improves cell viability in functional foods.

## Key findings

- Immobilized L. paracasei cells survived digestion better than free cells (>70% vs. <40%).
- Immobilized cells maintained viability (>7.5 log cfu/g) during 6 months of refrigerated storage.
- Cream cheese with immobilized cells retained high cell counts and improved sensory and volatile profiles.

## Abstract

During the last few decades, an urgent need for sustainable and health-promoting food products has been witnessed. In this vein, the development of functional foods enriched with probiotics has gained considerable interest from both the food industry and consumers. However, the maintenance of high cell viability until the time of consumption remains a significant challenge. In this study, freeze-dried immobilized Lacticaseibaciilus paracasei FBM_1327 cells on sunflower seeds were evaluated as a functional food ingredient, and their ability to survive during simulated digestion and storage at ambient and refrigerated temperatures in comparison to free cells was assessed. Cell immobilization resulted in higher survival rates (>70%) after in vitro digestion compared to free cells (<40%), while the freeze-dried immobilized cells maintained in cell levels >7.5 log cfu/g during storage for 6 months at 4 °C. In the next step, freeze-dried free or immobilized cells were incorporated in cream cheese (CCF and CCI samples, respectively) at a concentration of >8 log cfu/g. Cell viability of the immobilized cells remained stable (>8.1 log cfu/g) during storage, while live cell counts of free cells dropped to 7.51 ± 0.11 log cfu/g after 28 days. The fortification of cream cheese with immobilized L. paracasei FBM_1327 cells on sunflower seeds improved the volatile compounds profile, while all samples were accepted by the panel during the sensory evaluation.