Jankowska Agnieszka, Kiełczewska Katarzyna, Wachowska Maria, Dąbrowska Aneta, Siemianowski Krzysztof, Haponiuk Elżbieta, Stasiewicz Katarzyna
Department of Process Engineering, Equipment and Food Biotechnology, University of Warmia and Mazury, Oczapowskiego 7, 10-719 Olsztyn, Poland.
Department of Dairy Science and Quality Management, University of Warmia and Mazury, Oczapowskiego 7, 10-719 Olsztyn, Poland.
Foods. 2024 Apr 26;13(9):1327. doi: 10.3390/foods13091327.
The aim of this study was to determine the suitability of HP-treated caprine milk for yoghurt production and to evaluate the effect of HP treatment on yoghurt properties. Reconstituted caprine milk was subjected to HP treatment (350 MPa/10 min/20 °C); a lactic acid starter culture (YC-X16, Chr. Hansen) was added. Milk was fermented at a temperature of 43 °C until pH 4.60. Bacterial counts, pH, color, rheological characteristics, texture, microstructure, and the sensory attributes of the yoghurt were determined after production and after seven days of storage at a temperature of 4 °C. HP treatment increased color saturation and whiteness index and induced a minor increase in milk pH. Minor differences in the acidification curve were noted. During storage, counts were significantly higher in yoghurt from HP-treated than from untreated milk, whereas ssp. counts remained stable. A color analysis did not reveal differences between the experimental and control yoghurts. After storage, yoghurt made from HP-treated milk was characterized by thicker consistency and lower rheological stability than the control yoghurt. The micrographs of the yoghurts confirmed the differences in rheological parameters. Yoghurt produced from HP-treated caprine milk and stored for seven days received the highest scores in the sensory evaluation.
本研究的目的是确定经高压处理的山羊奶用于酸奶生产的适用性，并评估高压处理对酸奶特性的影响。将复原山羊奶进行高压处理（350兆帕/10分钟/20℃）；添加乳酸发酵剂（YC-X16，科汉森公司）。牛奶在43℃下发酵至pH值为4.60。在酸奶生产后以及在4℃下储存7天后，测定酸奶的细菌计数、pH值、颜色、流变学特性、质地、微观结构和感官属性。高压处理提高了颜色饱和度和白度指数，并使牛奶pH值略有升高。酸化曲线存在细微差异。在储存期间，经高压处理的牛奶制成的酸奶中的细菌计数显著高于未经处理的牛奶制成的酸奶，而嗜热链球菌计数保持稳定。颜色分析未发现实验酸奶和对照酸奶之间存在差异。储存后，经高压处理的牛奶制成的酸奶的特点是比对照酸奶更浓稠且流变学稳定性更低。酸奶的显微照片证实了流变学参数的差异。经高压处理的山羊奶制成并储存7天的酸奶在感官评价中得分最高。
