Abstract:
To address consumer demand for nutritious and functional foods, and to promote the diversification of dairy products as well as the high-value utilization of jujube and selenium-rich resources, this study developed jujube-flavored selenium-enriched yogurt melts by first preparing a selenium-enriched yogurt base using a composite starter culture consisting of selenium-enriched
Lactobacillus rhamnosus,
Lactobacillus bulgaricus, and
Streptococcus thermophilus, followed by the incorporation of jujube powder. The process parameters were optimized via single-factor and response surface methodology (RSM) experiments, with sensory evaluation as the key indicator. The optimal conditions were: 5% jujube powder addition, and pre-frozen at −45 ℃, then freeze-drying at 38 ℃. Under these conditions, the product achieved a sensory score of 87.38, with dietary fiber content of 0.32%, total selenium content of 19.27 μg/100 g, vitamin C content of 1.85 mg/100 g, and total antioxidant capacity (FRAP value) of 14.17 mmol/L. Compared to ordinary samples, the developed product exhibited higher levels of selenium, vitamin C, and dietary fiber, and better sensory and texture characteristics. Scanning electron microscopy and secondary structure analysis revealed a denser and more continuous microstructure, with an increased proportion of
β-sheet conformations, confirming improved protein structural stability. In addition, the product showed clearly improved instant solubility and antioxidant activity. In summary, this study provides a novel approach for functional dairy product development and resource utilization.