The study, published in LWT - Food Science and Technology, aimed to produce starch-based complexes with aroma compounds and also examine their potential for oral release by salivary fluids – based on the idea that encapsulation of flavors by starch complexes leads to increased stabilization, protection against spoilage, and could control retention and release profiles.
The authors found that the technique can provide a food-grade complex “of nanometric size”, which “could serve as an efficient platform for the control release of aroma in the oral cavity.”
“The results of the present work support the possibility of developing a nano-scale controlled release delivery system of aroma, based on native starches,” said the researchers, led by Eyal Shimoni, from the Israel Institute of Technology, Israel.
“It is evident that the starch-aroma complexes are stable at high temperatures, [at a] variety of pH’s and for long storage times at high water activity ... Most importantly, menthone and menthol were released from the complexes under simulated saliva conditions,” they added.
Shimoni and his colleagues noted that the encapsulation of flavor ingredients is a very attractive and widely investigated area of food science.
The researchers said that it is “well known that starch is able to form inclusion complexes with small molecules.” Since starch, they note, is a widely used component in food, the use of inclusion complexes based on starch “is of major interest,” due to the fact that salivary alpha-amylase breaks down the starch-aroma complex and releases the entrapped aroma compound while chewing.
In the new study, the research team used menthone, menthol, and limonene as model flavor compounds for complexation with starches of different amylose content.
The researchers found that that both menthone and menthol are able to form V-amylose complexes in a food grade process, “while limonene does not form such complexes efficiently.” They reported that complexation increased with amylose content in the starch for both menthone and menthol.
“Using the release kinetic model one can predict the amount of complexed aroma in the product according to the desired lasting time of flavor,” said the researchers.
Complexes were found to have more included aroma as the amylose content increased. Shimoni and his team added that aroma and flavor retention was tested and found to be stable under pH, temperature and storage challenges.
Results from digestion studies also suggested that the complexes are broken down by alpha-amylase in the mouth, leading to controlled release of the aroma in the oral cavity.
Source: LWT - Food Science and Technology
Published online ahead of print, doi: 10.1016/j.lwt.2011.08.008
“Complexation with starch for encapsulation and controlled release of menthone and menthol”
Authors: H. Ades, E. Kesselman, Y. Ungar, E. Shimoni