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Cross out contamination

According to the World Health Organization (WHO), an estimated 600 million people - almost 10 percent of the global population - fall ill after eating contaminated food. With safety regulations and global demand for food on the rise, optical and sensor-based sorting has become a necessity rather than a luxury for many producers who have previously relied upon manual sorting and inspection.

Sorting nuts with TOMRA's sorting equipment

Cross-contamination, or the presence of unexpected food matter in a supposedly homogeneous food type, is a serious issue that can have significant implications for the global food industry.

To combat the issue of contamination, many food manufacturers, processors, and retailers are embracing the ever-changing technologies and systems available to them. TOMRA Food’s sorting machines use a variety of sensors that go far beyond the commonly used color cameras. Near Infra-Red (NIR) spectroscopy enables an analysis of the molecular structure of a product while x-rays, fluorescent lighting, and lasers measure the elemental composition of objects. In addition to its color and shape, an object’s surface structure and biological fingerprint can be effectively analyzed.


An important reason for the identification and removal of contaminants is to reduce the accidental spread of allergens. This is particularly important since the societal impact of causing an allergic reaction in an unsuspecting member of the public can have substantial repercussions, not only financially and legally, but also in terms of brand reputation.


Although relatively well-known, cross-contamination does not end with allergens. Due to variations in national food standards, the issues caused by cross-contamination can have a negative impact upon the global movement of food. For example, corn, a commodity the US grows more of than any other country, can be grown naturally or it can be genetically modified (GM). This difference is suitable for domestic markets but can cause issues internationally.

It is estimated that the United States exports between 10 and 20 percent of its corn yield to global markets, the sales of which had a reported value of $7.6 billion in fiscal year 2014. When this is married with the fact that half the home nations within the European Union forbid the growing and importing of GM corn, organic corn from the US that has been cross-contaminated with its modified counterpart cannot be sold. This results in reduced yield efficiencies, increased food waste and diminished financial returns.

In addition, the scale for potential cross-contamination extends beyond savoury foods and into confectionary. Vitamin enhanced gummies are growing in popularity and many manufacturers have different products for adults and children - type A and type B respectively. Due to the varying vitamin dosages found in both, it’s imperative that gummies with a type A dosage do not cross-contaminate any with a type B dosage, as this could invariably lead to children consuming gummies with a vitamin dosage designed for adults.


  • Food safety
  • Reduced opportunities to cause harm to consumers
  • Reduction of food waste
  • Optimised yield
  • Protect your reputation

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