Physicochemical and Rheological Properties of Stirred Yoghurt during Storage Induced from High-Intensity Thermosonicated Goat and Cow Milk
Eman Saad Ragab,
Shuwen Zhang,
Sameh A. Korma,
Magdalena Buniowska-Olejnik,
Sahar Abd Allah Nasser,
Tuba Esatbeyoglu,
Jiaping Lv,
Khaled Sobhy Nassar
Affiliations
Eman Saad Ragab
Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
Shuwen Zhang
Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
Sameh A. Korma
Department of Food Science, Faculty of Agriculture, Zagazig University, Zagazig 44519, Egypt
Magdalena Buniowska-Olejnik
Department of Dairy Technology, Institute of Food Technology and Nutrition, University of Rzeszow, Ćwiklinskiej 2D St., 35601 Rzeszow, Poland
Sahar Abd Allah Nasser
Food and Dairy Science and Technology Department, Faculty of Agriculture, Damanhour University, Damanhour 22516, Egypt
Tuba Esatbeyoglu
Department of Food Development and Food Quality, Institute of Food Science and Human Nutrition, Gottfried Wilhelm Leibniz University Hannover, Am Kleinen Felde 30, 30167 Hannover, Germany
Jiaping Lv
Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
Khaled Sobhy Nassar
Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193, China
The effect of high-intensity thermosonication (HIT) pretreatment (20 kHz frequency, output power 4000 W and 25% amplitude for 5, 10 and 15 min) on the physicochemical and rheological properties of stirred yoghurt made from goat milk was studied. Various parameters of the milk were evaluated, such as the particle size, pH and soluble calcium and phosphorus, while other parameters of the stirred yoghurt were evaluated during storage (up to 18 days), such as the rheological measurements, syneresis, pH values, titratable acidity, color, and sensory properties. The microstructure had more interconnected chains than the stirred yoghurt made from homogenized milk on the first day of the storage period. Moreover, the HIT process reduced the diameter of the fat globules in the goat milk, making them smaller than those of homogenized milk. This pretreatment could be used successfully in the production of stirred yoghurt to improve major quality parameters such as delayed syneresis, increased viscosity and enhanced sensory properties during storage.
