Defining Your Compositional and Functional Testing in Dairy Processing


For a large proportion of the global population, dairy products – such as milk powder, liquid milk, yogurt and cheese – provide a significant dietary source of protein, essential minerals and vitamins. In fact, 2018’s world trade in dairy products was 75 million tons, a YOY increase of 2.9%. That volume and velocity of consumption drives the necessity for robust testing throughout the mosaic of dairy product, dairy processes, and dairy plants.

To ensure food products are high quality and safe, dairy testing and quality analysis occurs regularly at different stages within the dairy supply chain – from raw milk collected at farm level to finished dairy products.

These tests are vital for the production of products that meet both regulatory requirements and customer expectations.

  • Compositional analysis – the product’s chemistry
  • Functional testing – the physics/behavior of the product

Compositional analysis

Milk is a highly nutritious food, composed of water, fat, proteins, lactose (milk sugar) and minerals. Monitoring the nutritional composition of collected milk is incredibly important for dairy farmers to ensure fair and honest business partnerships, both regionally and cross-border.

Primarily, this is through utilizing protein, fat and lactose content of milk as an accountable marker for dairy quality. The parameters assigned to these markers govern the price the dairy farm attains for its milk. Fourier-Transform infrared (FTIR) spectroscopy is a key technology in dairy analysis - widely applied for measuring the markers. By evaluating the comprehensive spectral fingerprint produced by the FTIR technology, the nutritional composition and quality of dairy products can be measured, validated, and recorded.

Consistent monitoring the compositional analysis of milk also delivers deeper insights into overall herd health, allowing farmers to selectively improve milk composition and the total milk yield of their herds. This is undertaken by analyzing collected milk for specific health markers such as somatic cell count and non-esterified fatty acids in milk.

Production line spectroscopy optimizes workflow

Over the previous decades, the dairy sector has been increasing its efforts to transition towards using more sustainable processes. As a result, increasing process efficiency and optimization is a key driver for many dairy stakeholders – especially for dairy processors looking to lower production waste and costs.

To reduce waste in the dairy production process, processors must examine the composition of dairy products at key stages of the process. This provides dairy processors with a higher level of control of their processes, which in-turn leads to the production of competitive, sustainable and high-quality products. As such, there is a growing demand for in-line spectroscopy solutions throughout production chains.

Similar to FTIR spectroscopy, near infrared (NIR) spectroscopy is a commonly applied technology for compositional analysis. However, NIR operates at a shorter wavelength, allowing for a more effective analysis of solid samples. Understandably, NIR technology is finding use in increasing the efficiency of the solid and colloid dairy food production process, such as chocolate, creams, yogurt, and especially, butter.

Fat is an important parameter of the butter production process. Consequently, butterfat content is heavily regulated globally. Standard regulations generally state that butterfat must be in the form of an emulsion of fat and water, and that butter must be composed of 80-90% butterfat by weight. For example, in the EU, unsalted butter produced from cream or milk must meet a minimum butterfat content, by weight, of 82% and a maximum water content, by weight, of 16% - with the remainder composed of non-fat milk materials.

In response, the composition of butter is regularly observed during production to help guarantee not only that products meet the regulation, but also to ensure that producers are not adding too much fat, creating costly products. Current methods for testing fat content, however, are often time-consuming and involve costly wet-chemical methods.

In-line NIR spectroscopy can rapidly monitor fat content and other parameters at all stages of the butter manufacturing process, dramatically reducing in-process variation and allowing for agile adjustments in the process to avoid the production of out-of-spec product.

Functional testing

The dairy sector is currently projected to grow at a rate of 1.8% per year over the next 10 years. To compete in the thriving market place, dairy producers are developing innovative dairy products with increasingly novel formulations. With more products available on the market, having the functional testing methods in place is essential to guarantee customer demands are met. The functionality of a product – how it cuts, how it melts, its mouth feel – dramatically influences the palatability, appearance, and ultimately, the sales of the product.

Beyond various chemical and textural analysis methods, viscometers provide producers with an intuitive and versatile technology to measure a wide range of functionality in their products, and to rapidly predict final product quality.

Within dairy processes viscosity, the resistance of a fluid to flow, is a vital parameter that must be studied and understood when designing new food production processes. For some dairy products, such as cream and, cultured milk food and beverages, poor understanding of these factors can lead to either spoilt products, or products of low-quality.

Measuring viscosity provides manufacturers with deep insight into a product’s functional behavior, allowing them to understand factors such as pourability, meltability, its performance in a dipping or coating procedures, or the ease with which it may be handled, or used in further processes.

Spot-on analyses assure spot-on dairy products

Optimizing production processes is a key goal for all stakeholders along the dairy production chain. To succeed in an increasingly competitive market, and manage evolving consumer demands, it is vital that industry-savvy solutions are leveraged to optimize dairy processes.

From the raw milk to final dairy products, PerkinElmer provides the dairy industry with advanced technologies to control quality, and deliver real-time intelligence to assist in product development, formulation, and optimization.


  1. Dairy Market Review, March 2019: Food and Agriculture Organization of the United Nations
  2. Chia-Lin Leea, Huei-Lin Liao, Standards and labeling of milk fat and spread products in different countries, The Journal of Food and Drug Analysis, Volume 26, Issue 2, 469 – 480
  3. FAO-UN. Global Dairy Sector: Facts. 2016. Food and Agriculture Organisation of the United Nations.