New software for smartphones could alert consumers to the presence of cancer-causing substances in processed meats such as sausages, ham, bacon, and salami.
Scientists in Spain have developed a technology consisting of a color-changing film dubbed ‘POLYSEN’ that consumers can adhere to meat products.
The labels get darker when they detect high quantities of nitrite, a meat preservative that can produce chemicals with the potential to cause cancer.
The user may then take a picture of the film with their smartphone, and custom-built software will analyze the color and provide a nitrite concentration number.
The technology was developed by scientists at Spain’s Universidad de Burgos and described in a recent article published in ACS Applied Materials & Interfaces.
They state, “There is a need to detect and regulate the various chemical compounds added to processed foods, such as processed meat.”
Our solution provides a significant improvement in terms of analysis time, user-friendliness, and ease of implementation.
Bacon, hot dogs, ham, and sausages (including Mortadella, Italian luncheon meat) are frequently treated with nitrite or nitrate to preserve their appearance and flavor.
Nitrites are commonly used to increase the shelf life of processed meats by inhibiting the growth of pathogenic bacteria such as salmonella, listeria, and botulism.
Importantly, they also impart an enticingly tart flavor and a pink tint to products such as bacon, making them more appetizing.
Although nitrate is rather stable, it can be transformed within the body into a more reactive nitrite ion.
In the stomach’s acidic environment or a frying pan’s high heat, nitrite can undergo a chemical reaction to produce nitrosamines, which have been related to the development of several malignancies.
Because of this, customers seek to minimize their consumption of these preservatives, but it has been difficult to assess how much is in a given item.
Therefore, the researchers created the new POLYSEN film, a polymeric sensor comprised of four monomers and hydrochloric acid.
First, to establish a “reference chart,” discs punched from the film were placed on five different meat samples for 15 minutes so that the monomer units and acid in the film could react with nitrite.
The meat samples had varying nitrite amounts, thus the researchers anticipated that the discs’ hues would vary.
The color was then developed by dipping the discs for one minute in a sodium hydroxide solution.
The greater the amount of nitrite in the meat, the yellower each film got.
The researchers then developed a smartphone application that uses colorimetry, a technique that uses light to estimate the concentration of specific substances.
When the sample disc is photographed with the reference chart, the software can provide a nitrite estimation.
In addition to store-bought meats, the researchers tested the film on their own prepared and nitrite-treated meat.
They discovered that the POLYSEN-based method yielded equivalent findings to the conventional and more difficult nitrite detection method.
Additionally, POLYSEN was compliant with European law on the migration of chemicals from the film to the meal.
Although the team has just demonstrated the technology thus far, it could give a user-friendly and cost-effective method for determining nitrite levels in foods in the future.
They write, “This study is meant as a proof-of-concept in which it has been proved that the methodology is applicable and effective.”
HOW DOES ‘POLYSEN’ WORK?
POLYSEN also referred to as a “polymeric sensor,” is a film composed of four monomers and hydrochloric acid.
For fifteen minutes, discs punched from the film are placed on meat samples to allow them to react with nitrite.
The discs are then removed and immersed for one minute in a sodium hydroxide solution to develop color.
The greater the concentration of nitrite, the deeper the yellow tint of the film.
When a chart of reference discs is captured in the same image as a smartphone app, the software calibrates itself.
