Near-infrared (NIR) analysis is a technique used for compositional measurements in many industries, including agriculture, ingredient processing, processed foods, and industrial applications. Typical measurements are for moisture, protein, fat, crude fiber, and other constituents, as well as physical property measurements, such as digestibility or hardness.
There are many features of NIR that make it a very attractive technique for monitoring manufacturing processes:
NIR is fast and typically takes a few seconds to 1 minute for sample analysis.
It is non-destructive and requires no dangerous chemicals to use or pay to dispose.
Little or no sample preparation is required.
Many sample types can be analyzed, including powders, slurries, and solids.
NIR analysis has minimal training requirements and produces operator-independent results.
NIR analyses are very accurate and highly repeatable.
NIR analyzers are used daily in thousands of food manufacturing plants where they provide rapid compositional data of incoming ingredients and in-process manufacturing of final product control. Historically, the majority of NIR analyzers are employed in one of three areas:
Incoming raw ingredients. In these applications, NIR analyzes incoming raw ingredients for compositional and physical or rheological parameters. These data are used to qualify incoming lots of raw materials to ensure proper compositional profile needed to support final product quality. NIR data can also be used to ensure ingredients meet contract specifications and support claims for out-of-specification materials.
In-process analysis of moisture and oil. In these applications, process NIR analyzers are positioned in or over a production line for real-time product analysis. Moisture and oil are two quality parameters that are easily measured with on-line analyzers. Real-time data is used to adjust process parameters, such as oven temperature or conveyor speed via feedback process control.
Final product inspection. Analysis of final products can be performed either on-line or via sampling at-line for a more thorough examination of product quality. Depending on the instrumentation and sampling, moisture, oil, and other parameters can be measured. While final product inspection ensures quality, it is a lagging indicator and not very effective for controlling the process.
At-Line Monitoring with High-performance NIR Analyzers
As the global food market has become increasingly specialized and competitive, food manufacturers are increasingly using high-performance NIR analyzers at-line to monitor production and reduce raw material costs.
At-line analysis with frequent sampling provides the real-time data production managers require for responsive process control. Moving the analysis next to the production line allows the use of NIR analyzer technology and calibrations which can accurately measure more difficult constituents, such as seasoning or sugar. For many processes, these ingredients are applied with sprayers or tumblers which can deliver an inconsistent application and final concentration. Regular at-line monitoring of these critical ingredients improves product quality and reduces over-formulation waste. As global commodity prices fluctuate and significant increases are occurring in 2021, over-formulation can have an enormous impact on the bottom line.
Here are two examples that illustrate how at-line inspection can deliver an immediate return on investment (ROI) while improving product quality and consistency.
Example 1: A medium-sized breakfast cereal plant was applying sugar using tumbling applicators.
The amount of sugar that ends up on the final product is a function of many factors, including the moisture in the sugar mix, humidity, cereal temperature, etc. As sugar is crucial to consumer acceptance, the amount of sugar used was over-formulated by 2% (from 10% to 12%) to ensure enough sugar coating on the final product. By implementing regular at-line inspection of the in-process samples, this manufacturer reduced their sugar use by over 15%, saving $3,000 USD per day.
Example 2: A snack food operator applied seasoning using spray nozzles over a conveyor belt.
Plant managers adjust the seasoning load by regulating the sprayer pump, but changes in the consistency of the seasoning, clogged nozzles, and other factors can influence the seasoning load and led to the production line applying excess seasoning to ensure proper coverage.
A SpectraStar™ Analyzer installed on the production floor was configured with a custom calibration made for seasoning. Through regular monitoring of production samples, plant managers were able to run closer to their target and reduced the seasoning by almost 5%, saving over $1,000 USD per day.
Both of the examples above had the following characteristics:
The critical ingredient was applied by tumbling or spraying and not in a batch mode; thus, the content in the final product was variable and inconsistent.
The component measured was critical to the quality and consumer acceptance of the final product and represented a significant portion of the raw material cost.
Adjustments were made for process control based on the data collected at-line.
SpectraStar™ XT NIR Analyzer
The Unity Scientific SpectraStar™ XT NIR Analyzerfrom KPM Analytics is an ideal solution for at-line applications like processed and snack foods, with features like:
Scanning monochromator technology that offers the best quality NIR signal available, enabling the analysis of more difficult parameters like sugar or seasoning.
Operators get reliable and accurate results in under a minute with little or no sample preparation.
The XT has a stand-alone design with a sealed case and touch screen operation that is perfect for at-line installations.
Intuitive software and easy operation has a minimal training requirement for plant personnel to achieve operator-independent results.
One SpectraStar XT analyzer can support several production lines, leveraging the analytical capability and multiplying the ROI.
Custom calibrations can be created to measure critical constituents in unique or proprietary end products.
Reduce Over-Formulation for Rapid ROI
The examples above demonstrate how high-performance at-line NIR analysis can provide food producers with the data needed to reduce over-formulation of costly ingredients with confidence. Regular at-line monitoring of food production lines can deliver lower raw material costs and ensure consistent product quality for many processed food applications.