The spectral signature of bread made with natural sourdough!
The label will no longer be the sole indicator of a product's ingredients or quality. A spectroscopic signature is on the way: a unique and unambiguous indicator of a food's characteristics and properties. This will help ensure consistent quality standards for consumers, producers and distributors alike.
This was revealed in a study of naturally leavened bread conducted by research groups led by Cesare Manetti and Carlo Giuseppe Rizzello of Sapienza University of Rome, in collaboration with the University of Bari 'Aldo Moro', and published in the scientific journal Food Chemistry. The study was carried out as part of METROFOOD-IT, a research infrastructure coordinated by ENEA.
Researchers succeeded in ‘deciphering’ and recognising the ‘signature’ of bread made with natural yeast by using a spectroscopic method based on the interaction of electromagnetic waves with matter. This is a non-destructive method, as the sample is not necessarily lost, and is easy to use thanks to portable analysis equipment that provides automatic responses based on database comparisons.
The study made particular use of near-infrared spectroscopy (NIR), together with statistical models applied to chemistry and biochemistry and the analysis of data relating to biotechnology in the production of baked goods.
What happens when an infrared ray passes through a slice of bread? It leaves a trace, represented by a curve that corresponds to the vibrations of the molecules, whose oscillations are conditioned by the material's characteristics.
The curve can therefore be interpreted as a signature, whose letters and the way in which they are written depend not only on the vibrations of the molecules, but also on their interaction and on the microscopic structure of the slice of bread, determined by the technological/biotechnological process that characterises that production.
Due to the complexity of the interactions, the trace will therefore unequivocally identify a specific product, becoming a useful tool for ascertaining its authenticity, as well as its consistently high-quality standard.
As a matter of fact, quality attributes are not exclusively linked to ingredients, but also to technological processes (type of tools used in processing: mills, ovens, etc.) and biotechnological processes (fermentation phenomena often occur in production processes where particular microorganisms express different capacities for biotransformation of natural substrate molecules).
In the near future, the increasingly widespread sharing of ‘spectroscopic signatures’ will be central to the creation of reference databases aimed at producing authentication models for other products.
This approach will be increasingly used with a view to creating genuine ‘food passports’ to protect food and wine excellence, where ‘spectroscopic signatures’ will constitute unalterable ‘photos’ of food.
Focus
METROFOOD-IT is a research infrastructure coordinated by ENEA and funded by the PNRR, in which Sapienza University is a partner. Its specific aim is to ensure the safety and quality of agri-food supply chains by implementing a multidisciplinary approach that provides a comprehensive description of production processes, from field to table.
The study was conducted at the Department of Environmental Biology of Sapienza University, which has a research infrastructure laboratory. The expertise of spectroscopists and experts in statistics and mathematical models applied to chemistry and biochemistry was combined with that of food technologists and microbiologists to define methods for ascertaining the authenticity of bread made with natural yeast. Researchers from the Department of Soil, Plant and Food Sciences at the University of Bari “Aldo Moro” also collaborated on the study.
References
Development of a novel NIR spectroscopy-based chemometric model for sourdough bread authentication. Gabriele Lombardi, Federica Violetta Conti, Consuelo Giustizieri, Erica Pontonio, Giuseppe Perri, Cesare Manetti, Carlo Giuseppe Rizzello, Michela Verni.