Carrillo-Lopez Luis M, Juarez-Morales Monica G, Garcia-Galicia Ivan A, Alarcon-Rojo Alma D, Huerta-Jimenez Mariana
Faculty of Animal Science and Ecology, Autonomous University of Chihuahua, Perif. Francisco R. Almada km 1, Chihuahua, Chih 31453, Mexico.
National Council of Science and Technology, Av. Insurgentes Sur 1582, Col. Crédito Constructor, Del. Benito Juárez, Ciudad de México 03940, Mexico.
Foods. 2020 Mar 9;9(3):313. doi: 10.3390/foods9030313.
High-intensity ultrasound could be an alternative to pasteurization for cheeses made with fresh raw milk, the properties of which must be preserved as part of their intangible cultural heritage, such as Panela cheese in Mexico. This research aimed to study the effect of the amplitude (50% and 100%) and application time (0, 5, and 10 min) of ultrasound treatment of fresh raw milk, on the yield and microbiological and physicochemical qualities of Panela cheese after 24 h of storage at 4 °C. The yield was increased to 24.29% with 10 min of ultrasonication, although the amount of exudate was higher in the ultrasonic product than in the control (20.33%). As the ultrasonication time increased, the yellowness (b*) increased significantly, while the hue angle decreased (with values close to 90°), resulting in evident yellow tones in cheeses made with milk treated for 10 min. The pH significantly increased from 6.6 to 6.74 with 5 min of ultrasound, but decreased to 6.37 with 10 min of ultrasonication. Although no significant differences were found in fat content, the protein significantly increased with 5 min of sonication, but it decreased markedly when ultrasound was applied for 10 min. Ultrasound treatment with amplitudes of 50% effectively decreased the counts of coliform bacteria regardless of ultrasonication time. However, the mesophilic bacteria increased by a 0.9 log with an amplitude of 100% and 10 min treatment. The results showed that ultrasound improved the yield and microbial, nutritional, and physicochemical properties of Panela cheese.
对于用新鲜生牛奶制作的奶酪，高强度超声可以替代巴氏杀菌法，这类奶酪的特性作为其非物质文化遗产的一部分必须得以保留，比如墨西哥的帕内拉奶酪。本研究旨在探究新鲜生牛奶超声处理的振幅（50%和100%）及处理时间（0、5和10分钟）对帕内拉奶酪在4℃储存24小时后的产量、微生物及理化品质的影响。超声处理10分钟后，奶酪产量提高到了24.29%，不过超声处理产品的渗出物量高于对照产品（20.33%）。随着超声处理时间增加，黄度（b*）显著增加，而色调角减小（值接近90°），使得用处理10分钟的牛奶制作的奶酪呈现出明显的黄色调。超声处理5分钟后，pH值从6.6显著升至6.74，但超声处理10分钟后又降至6.37。尽管脂肪含量未发现显著差异，但超声处理5分钟后蛋白质含量显著增加，而超声处理10分钟时蛋白质含量显著下降。振幅为50%的超声处理无论处理时间长短均能有效降低大肠菌群数。然而，振幅为100%且处理10分钟时，嗜温菌数量增加了0.9个对数级。结果表明，超声改善了帕内拉奶酪的产量以及微生物、营养和理化特性。
