Application Notes - Magnetic Resonance

Improved Encapsulation of Lycopene Achieved with Alginate-calcium Bead

Alginate-Ca(II) beads could then be incorporated in a variety of products, from dairy products to desserts, as well as snacks and candies, for the production of the so-called functional foods.

“Alginate-Ca(II) beads could then be incorporated in a variety of products, from dairy products to desserts, as well as snacks and candies, for the production of the so-called functional foods”

It is becoming increasingly common for the food industry to add health-promoting additives, such as antioxidants, minerals, vitamins and phytosterols, to foods. It is necessary to protect such bioactive molecules from the environment in order to increase their stability during storage and prevent reaction with other components of food, such as water, so that their beneficial properties are maintained1.

Encapsulation is a common means of introducing such a barrier between active compounds and their surroundings. The carrier materials most widely used for encapsulation in food applications are polysaccharides.

The substantial health benefits of eating a diet rich in antioxidants has sparked the desire to increase the level of antioxidants in our diet. Antioxidants mop up excessive damaging free radicals, reducing the risk of premature aging and a range of debilitating disorders.

Increasing the amount of antioxidants can reduce the risk of cancer, cardiovascular disease, diabetes, Alzheimer’s disease and macular degeneration2. Antioxidants are found in many fruits, vegetables, nuts, beans and berries.

However, there is much interest in adding antioxidants to manufactured foods to further boost antioxidant intake to reduce free radical damage and the risk of disease. Lycopene is a naturally occurring powerful antioxidant3 and there has been extensive research to facilitate its incorporation into common foodstuffs.

A popular method of encapsulation is using alginate-calcium beads. This is a relatively low cost and environmentally-friendly option. It is of especially suitable for use in the food industry since the carrier material is non-toxic, biocompatible, and thermally and chemically stable. It has already been effectively used in drug-delivery systems.

Although encapsulation of lycopene has been achieved using alginate-calcium beads, the quantities of lycopene contained in the final capsules have been rather disappointing. Researchers have recently modified the composition of alginate-calcium encapsulation material and achieved incorporation of greater quantities of lycopene4.

By adding chitosan, the molecular mobility and the diffusion coefficient of the alginate-calcium beads were considerably reduced. This allowed less lycopene to escape during the encapsulation process. Consequently, a higher lycopene content was achieved. It was also found that adjusting the composition of the beads resulted in changes in the rate of release of the lycopene from the capsule4. Thus, in addition to allowing high-content lycopene encapsulation suitable for human consumption, this novel encapsulation methodology will also facilitate the tailoring of lycopene formulations with release rates appropriate for specific applications.

In this study, a Bruker minispec mq20 low-field proton nuclear magnetic resonance (LF-NMR) spectrometer was used to measure proton transverse relaxation times and diffusion coefficient.

Visit Bruker’s website to learn more about the minispec mq20.


  1. Zeller BL, et al. Trends in development of porous carbohydrate food ingredients for use in flavor encapsulation. Trends Food Sci Technol. 1999;9:389–394.
  2. Sen L, et al. Research progress of natural antioxidants in foods for the treatment of diseases. Food Sci Hum Wellness 2014;3:110–116.
  3. Kelkel M, et al. Antioxidant and anti-proliferative properties of lycopene. Free Radic Res. 2011;45(8):925-940.
  4. Aguirre Calvo TR and Santagapita PR. Encapsulation of a free‑solvent extract of lycopene in alginate-Ca(II) beads containing sugars and biopolymers. Biol. Technol. Agric. 2017;4:16.