High-pressure processing and thermal pasteurization of blueberry purée-based baby food differentially modulate polyphenol bioaccessibility and intestinal cell responses

Abstract

Abstract Proper processing of baby foods, ensuring both safety and the highest possible nutrient retention and bioaccessibility, is of particular importance for the health and development of infants and young children. In this study, blueberry purée-based baby food was subjected to conventional thermal pasteurization (TP) and high-pressure processing (HPP) at moderate temperature, and their effects on sensory quality and the availability of bioactive compounds were compared. Polyphenol stability and antioxidant bioaccessibility were evaluated during storage and simulated gastrointestinal digestion, while intestinal cell responses and prebiotic-related activity were assessed separately. HPP-treated purées showed significantly higher phenolic bioaccessibility, whereas differences in antioxidant bioaccessibility and anthocyanin recovery between treatments were not statistically significant. Caco-2 cell viability varied with treatment and incubation time, whereas intracellular reactive oxygen species levels were not significantly affected by processing treatment and decreased with incubation time. The effects of both preservation methods on microbial growth were dependent on bacterial group and incubation time. Positive PAS values were observed for Lactobacillus after both 24 and 48 h, whereas Bifidobacterium did not show a selective growth advantage over Enterobacteriaceae under the applied experimental conditions. Short-chain fatty acids remained below the detection threshold in the fermented purée samples and the inulin control, although several unsaturated fatty acids were quantifiable after fermentation in both processed purées. These results demonstrate that HPP and thermal pasteurization differentially modulate the functional properties of blueberry purée-based baby food and highlight the importance of preservation strategy selection in the development of foods intended for sensitive consumer groups.