Incorporation of mixed strawberry and acerola jam into Greek-style goat yogurt with autochthonous adjunct culture of Limosilactobacillus mucosae CNPC007: Impact on technological, nutritional, bioactive, and microbiological properties

Abstract

This study aimed to assess the impact of adding strawberry and acerola jam, along with Limosilactobacillus mucosae CNPC007, on the technological, nutritional, bioactive, and microbiological properties of Greek-style goat yogurt. Six yogurt formulations were developed: without and with the addition of L. mucosae CNPC007 (CY and PY, respectively), and with 10 % and 15 % jam (CY10, CY15, PY10, and PY15, respectively). The inclusion of jam enriched the yogurt with phenolic compounds and significantly enhanced antioxidant activity, as measured by FRAP and ABTS assays. The highest values were observed after 28 days of storage in the PY15 formulation (0.177 ± 0.01 and 3.43 ± 0.01 µmol TEAC/g, respectively), compared to CY (0.013 ± 0.01 and 0.19 ± 0.01 µmol TEAC/g, respectively) and PY (0.010 ± 0.01 and 0.23 ± 0.01 µmol TEAC/g, respectively). This increase was likely driven by the presence of anthocyanins and flavonoids in the jam, as indicated by heatmap correlation analysis. DPI and EPI were also influenced by the addition of jam and L. mucosae CNPC007, with EPI increasing in the PY10 and PY15 formulations, reaching approximately 40 % after 28 days. The incorporation of jam resulted in a decrease in the L* (<90) and an increase in the b* (>14) color parameters. Additionally, jam-enriched formulations exhibited higher syneresis and lower water retention capacity (WRC) throughout storage compared to control formulations, with average syneresis exceeding 26 % and WRC falling below 75 % after 28 days. In general, all yogurt formulations showed a reduction in lactose, an increase in glucose and galactose, and the production of lactic acid during storage. The lower lactose content observed after 28 days of storage in the PY (0.84 ± 0.01 g/100 g), PY10 (0.82 ± 0.01 g/100 g), and PY15 (0.98 ± 0.01 g/100 g) formulations indicates active sugar metabolism by L. mucosae CNPC007. All formulations met microbiological safety standards, confirming their suitability for consumption. Formulations containing L. mucosae CNPC007 showed viable cell counts exceeding the minimum recommended to produce health benefits (>7 log CFU/g) throughout the 28-day refrigerated storage and after in vitro digestion. These findings underscore the potential of combining tropical fruit jams with probiotics to develop a multifunctional, value-added yogurt product that delivers substantial health benefits to consumers.