Halogen moisture analyzer how to determine milk

Test probe P100-B can be customized for other specifications

Kaixin micro test

Test - lowercase jpg

Abstract: Whole milk solids are a critical parameter in the analysis of milk and yogurt. Traditional methods such as GB5409-85 and GB/T5009146-2003 have been widely used, but they come with limitations. The first method relies on calculation, which is rarely applied due to the complexity and high cost of fat measurement. The second method, oven drying, is time-consuming, taking up to 4–5 hours per sample, making it unsuitable for large-scale testing in industrial settings.

In recent studies, Yuan Xu et al. [3-5] improved upon the GB5409-85 method by optimizing the evaporation process, using filter paper instead of sea sand to eliminate the water bath concentration step, and achieving faster results. This approach reduced the measurement time from 5 hours to just 1.5–2 hours, lowered costs, and allowed for simultaneous testing of up to 10 samples per batch. Building on this work, this article explores the use of the MB45 halogen moisture analyzer for rapid and accurate determination of total solids in milk and yogurt.

I. Materials and Methods

1. Halogen Moisture Analyzer

The study utilized the Vico Merto/VicoMeter VM-S series halogen moisture analyzer (referred to as the halogen moisture meter) for all measurements.

2. Determination Method

A well-mixed sample of 10 g was placed into an aluminum dish and evenly spread using a spatula. The sample was then measured under optimal conditions according to the manufacturer’s instructions for the halogen moisture analyzer.

3. Results and Discussion

4. Selection of Optimal Measurement Conditions

The total solid content in milk and yogurt is determined based on the mass loss after moisture removal. In practice, the heating rate plays a crucial role. Using a halogen lamp allows for rapid temperature rise and maximum heating power in the shortest time. For samples with high moisture content, the high-temperature phase can be extended, while for high-sugar samples, it should be shortened to avoid charring. The optimal conditions for measuring whole milk solids were found to be: 190°C for 3 minutes, followed by 120°C for 5 minutes, and finally 105°C until constant weight is achieved.

2. Comparison between the Halogen Moisture Meter Method and the National Standard Method

The total milk solids were analyzed using both the halogen moisture meter and the national standard method (GB/T5009146-2003) for 11 milk samples and 10 yogurt samples. The results are presented in Table 1. A t-test was conducted, and the results showed that for both milk and yogurt, the calculated t-values were lower than the critical t-values at a 0.05 significance level, indicating no statistically significant difference between the two methods. This suggests that the halogen moisture meter can effectively replace the traditional national standard method.

Precision measurement was also performed. Seven repeated measurements were conducted on a single milk and yogurt sample, yielding RSD values of 0.82% for milk and 1.50% for yogurt, demonstrating good repeatability.

Uncertainty analysis was carried out using the data from Table 2. With a coverage factor of k=2, the uncertainty for milk was U = (10.85 ± 0.07) g/100g, and for yogurt, U = (21.13 ± 0.24) g/100g.

Time comparison revealed that the VM-S series halogen moisture analyzer significantly reduces measurement time compared to the traditional oven method. While the national standard method requires at least 8–12 hours per sample, the halogen moisture analyzer completes the same task in just 13 minutes for 10 yogurt and 11 milk samples. This fast, automated process greatly improves efficiency in laboratory and production environments.

In conclusion, the use of the Vico Meituo halogen moisture analyzer for determining total milk solids offers a reliable, efficient, and accurate alternative to conventional methods. By adjusting automatic end points, it reduces test duration and enhances productivity, making it ideal for routine quality control in dairy industries.