Tutorial: How Near Infrared technology is used in the snack food industry

Near infrared technology (NIR) has historically been used in the snack food industry for measuring moisture and oil, the two most critical constituents for controlling a snack food process. In addition to measuring moisture and oil in raw ingredients, in-process products and finished snacks, devices such as the Unity Scientific SpectraStar XT can measure the seasoning content that has been applied to the chips.

Added seasoning is the costliest part of the snack manufacturing process. For example, adding 1–2% more than the target seasoning amount will add thousands of dollars per week to manufacturing costs. Under- or over-seasoning of product will lead to customer complaints and eventual loss of market share.

Seasoning measurement in a snack plant varies widely. Some manufactures do not measure at all because they trust their application hardware to work correctly. This is very dangerous, as applicators often get clogged or fail. Furthermore, simply calculating how much seasoning is used based on how many pounds of chips are produced does not accurately reflect the amount of seasoning applied to the chips.

Other tests used for seasoning measurement are:

• Color measurement – The concept is that the darker the product, the more seasoning is applied. This could be quantified by a color meter. The drawback here is that some seasonings are clear and cannot be measured by a typical color meter.
• Salt Measurement – In many cases, the salt in a snack product is added in the seasoning. If the amount of salt in a seasoning lot is known, it is easy to calculate how much seasoning is applied to the product if the salt in the seasoned chips is measured. The typical salt test is a titration ranging from a very simple, operator-driven test to an automated instrument with an auto-sampler.

Simple salt titrations are very subjective and vary widely from operator to operator. This causes issues with accuracy. All titrations use Silver Nitrate in the method. The chemicals used in the test are expensive, and disposal of silver nitrate is expensive as well. Furthermore, titrations take approximately 5–15 minutes per sample.

A rapid method for analyzing seasoning accurately and quickly is needed in the snack food industry.

Read more at the KPM Analytics blog