The Impact of Barley Bran Powder on the Physicochemical, Rheological, and Sensory Properties of Probiotic Low-Fat Cheese: A Response Surface Methodology Approach

Background: This study was conducted to produce probiotic cheese containing barley (Hordeum vulgare) bran, optimizing its physicochemical, rheological, and sensory characteristics while maximizing the viability of Lactobacillus acidophilus over a nineday storage period at 4 °C.Methods: Using the Response Surface Method (RSM), 13 treatment combinations were designed, including barely bran concentrations ranging from 0% to 4% and storage durations extending up to 42 days.Two types of cheese were evaluated: probiotic cheese and probiotic cheese containing barley bran.Comprehensive assessments included microbial viability, physicochemical variables (such as pH and acidity), rheological properties, and sensory evaluation.Results: The highest viability of probiotics, recorded at 8.7 log CFU/g, was observed in the probiotic low-fat cheese on day 1 with a barley bran concentration of 4%.The physicochemical analysis indicated suitable pH and acidity levels.Rheological characteristics, such as viscosity and hardness, were enhanced in barley bran samples, whereas adhesiveness showed no significant change.The color index (L*) decreased in the samples with added barley bran.Conclusion: Incorporating 2.37% barley bran into the cheese formulation resulted in a product with optimal physicochemical, rheological, and sensory properties.In addition, the population of L. acidophilus bacteria increased to 8.21 log CFU/g, and these characteristics were maintained for approximately nine days during refrigerated storage (4 °C).