New research suggests the brown-coloured melanoids produced during thermal processing of foods and drinks have potential as functional ingredients to be used in foods.
The Spanish team behind the work, noted that the nitrogen-containing compounds, which are produced in the late stages of the Maillard reaction that is most often cited as the primary source of acrylamide in foods, could be produced as single ingredients and also have great potential as value-added ingredients that can be recovered from food processing waste.
“Many beneficial effects have been associated to these compounds, such as antioxidant, antimicrobial, anti-inflammatory, antihypertensive or prebiotic activity. For this reason, recent studies have been focused on the potential use of melanoidins present in both foods and by-products of foods as functional ingredients in the search for healthier and tasty foods,” said the team – led by Marta Mesías from the Spanish Institute of Food Science and Technology and Nutrition (ICTAN-CSIC) in Madrid.
Writing in Current Opinion in Food Science, Mesías and colleagues noted that as a consequence of the thermal treatment applied to food and drinks, melanoidins are already ‘widely distributed’ and are a part of our daily diet.
“These products are mainly responsible for specific colour and typical appearance of processed foods, which greatly improve the acceptance by consumers,” said the Spanish team – who noted that recent research melanoidins contribute to 20% of the total antioxidant capacity intake in the Spanish population.
“Thereby, these compounds are found in coffee and bakery products, cooked potatoes, cocoa, roasted barley or sweet wine,” they added. “Among these foods, coffee and bakery products are the most significant sources of melanoidins in Western diets.”
The authors noted that a variety of techniques allow the extraction of melanoidins from foods and food by-products.
They noted that the use of a model system which produced melanoidins under specific controlled conditions is the simplest solution for the generation of new functional ingredients.
However, they noted that recovery of melanoidins from waste and by-products is also a growing commercial opportunity – but noted that for food products, like coffee, bread, biscuits or different beverages, “the characterization of melanoidins is by far more complex.”
Indeed, the procedures involved in the extraction and isolation of melanoidins is largely dependent on their structure and the food system, said Mesías and colleagues.
“Although from a chemical point of view the knowledge of their structure is still uncertain, it is assumed that two main typologies are found in foods: polysaccharide-type melanoidins, as those present in coffee brew, and proteinaceous-type melanoidins, known as melanoproteins, predominant in bakery products,” they said.
"On the base of the scientific data on health-promoting properties of melanoidins, an interesting opportunity is guessed for the near future: their potential use as a functional food ingredient,” the Spanish research team wrote.
“The exploitation of coffee by-products including coffee silverskin and spent coffee has been proposed as an important source of melanoidins which, in turn, allows revaluing these leftovers and decreasing the environmental problem.”
Source: Current Opinion in Food Science
Volume 14, Pages 37–42, doi: 10.1016/j.cofs.2017.01.007
“Melanoidins as a potential functional food ingredient”
Authors: Marta Mesías, Cristina Delgado-Andrade