[Application] Stability analyzer MS20 studies the gel formation process of yogurt at different temperatures

Yogurt, as one of the popular dairy products, is becoming increasingly diverse in taste and texture. Understanding the process of yogurt formation is crucial for regulating its production process. The formation principle of yoghurt is to use bacteria to make milk gel. Generally, casein micelles solidify in the temperature range of 42 ° C -45 ° C to form a gel network. Therefore, temperature is an important factor in the gel process, which will significantly affect the gel point, and then affect the taste and quality of yogurt. The traditional research method is to study the process by measuring the pH value, but the information that the pH value can provide in the process of real gel formation is very limited.

The MS 20 stability analyzer (Figure 1) developed and produced by German company Data Physics is based on the theory of multiple light scattering. By measuring the changes in the intensity of backscattered and transmitted light in a dispersed system, the stability of the dispersed system can be evaluated by capturing its characteristics over time and temperature.

This article introduced the use of MS 20 stability analyzer to study the influence of temperature on the yogurt gel process and its guiding role on the quality of yogurt.

Figure 1, MS 20 Multiscattered Light Scattering Stability Analyzer from German company Dataphysics. Up to 6 measurement towers (6 samples) can be connected, and the measurement towers can measure independently at the same time.

With the superposition function of MSC software, the difference of gel process at different temperatures can be directly presented. As shown in Figure 6, at an appropriate temperature of 45 ° C, the coagulation rate of casein micelles is faster and the gel point appears earlier. This result is of great significance for optimizing the temperature parameters of the fermentation process.

image6，at different temperatures, 3 samplesFlocculation kinetics of gel processcompare

In addition, throughbackThe change of scattering intensity can deduce the possible instability mechanism after the gel point，As shown in Table 1. This provides direction for optimizing production processes and product formulas for food research and development personnelgivehelp.

Table 1: Phenomena and possible instability mechanism after gel point during the formation of yogurt at different temperatures