Taste testing: New odor and tastant quality control method boasts faster and easier results

01 Aug 2019 --- A new methodology for the simultaneous analysis of odorants and tastants has been developed by scientists at the Technical University of Munich, Germany, and the Leibniz-Institute for Food Systems Biology. The methodology is based on an ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS) method typically used for taste analysis. It could allow food chemists to guarantee consistent sensory quality through a fast and precise food analysis, with higher throughput than traditional methods.

The researchers say that volatile odorous substances can now also be analyzed through upstream enrichment or a substance conversion step using this method, which is otherwise not used for aromatic substances.

“Sensory quality is the key factor for consumer’s decisions to buy a product, with consumers expecting their preferred sensory profile every time they buy the product. Therefore control of the sensory quality is very important for product success. In addition, optimization of raw material selection and processing steps with a focus on sensory quality can help to reduce additive addition,” Andreas Dunkel, Senior Scientist at the Leibniz-Institute of Food Systems Biology and co-author of the publication, tells FoodIngredientsFirst.

Consumers expect products to have a consistent and reliable sensory profile.The methodology could be used to simplify and accelerate food quality control as odorants and tastants are what determines whether a food tastes good or not. A few trillionths of a gram per kilogram of food are enough to perceive odorants, while tastants are only recognized at significantly higher concentrations. It is vital that manufacturers can measure and control the characteristic odor and taste profiles of their products from the raw material to the finished product. 

Currently, food chemists use various methods to determine the exact nature and quantity of odorants and tastants in raw material or food. However, the time-consuming and expensive nature of this limits the high-throughput analysis of numerous samples.

“Labs already working on food analysis should be able to implement the method with only minor investments. By far, the most expensive device needed is the LC-MS/MS instrument, but this is already used by many labs for analysis of contaminants, residues and more. The consumables costs of the method are similar to a traditional odorant analysis by GC-MS with the advantage of higher throughput and less manpower,” says Dunkel. 

He also notes that the main challenge was the sensitive detection of volatile odorants (which are usually analyzed by means of GC-MS) with the LC-MS instrument. This was achieved with a new generation of highly sensitive instruments and application of a derivatization methodology to convert the volatile analytes into a form, which could be better ionized by the electrospray ionization used in LC-MS.   

“Some collaboration partners in the food industry have already started to implement the methodology in their labs. We also plan to publish the application of this approach on more complex products soon, which should increase the interest in the use of LC-MS for odorant analysis,” Dunkel continues. 

Moving forward, the researchers hope to develop the method so it can be used to quickly and easily monitor the flavor of food along the entire value chain and, if necessary, optimize it. The testing process only used apple juice as an example. “We want to expand the compound coverage, ideally we will be covering the entire set of key food odorants. Additionally, we aim to extend to other products, especially solid materials like chocolate in combination with high-speed homogenization and extraction,” notes Dunkel. 

He adds that the new method could also be used to stop food fraud. “Using the identified flavor profiles, it would be possible to check the origin and quality label of the manufacturers and detect food fraud.”

Meanwhile, Givaudan and Bühler are joining forces to fast-track innovation and accelerate market access for start-ups. Food fraud and authenticity are among the partnership’s key interests, along with alternative proteins, sustainable animal feed, food safety, natural ingredients for food applications (colors, preservatives), flavors, nutrition (particularly fiber, sugar, fat and salt reduction), ingredients with proven health and nutrition benefits and gentle processing.

By Katherine Durrell