Stability of beta-carotene entrapped in Ca2+
crosslinked alginic acid nanoparticles
Beta-carotene is a natural, lipophilic pigment found most commonly in fruits and vegetables which is a majorsource of vitamin A. Due to its many health benefits, the food industry has sought to increase its incorporation into foodproducts. However, because beta-carotene is insoluble in water and very unstable to light, heat and air, its use in food products has proven difficult. Many nanodelivery systems, of varying stabilities, have been developed to uniformly dispersebeta-carotene in water and to improve its solubility. The purpose of this paper was to test beta-carotene degradation whenentrapped in Ca2+ cross linked alginic acid nanoparticles (NP) as a function of storage conditions, light, air andtemperature. Beta-carotene degradation was determined spectrophotometrically and colorimetrically at different nanoparticle concentrations (0.21 mg NP/ml and 12.85 mg NP/ml). It was found that storage under dark conditions, at lowtemperature and in the presence of nitrogen caused beta-carotene nanoparticles to remain stable the longest (7 percentdegraded after 814 hours at 12.85 mg NP/ml). The presence of oxygen played an important role in the diluted sample, butnot in the concentrated samples which degraded similarly in the presence or absence of air. At 12.85 mg NP/ml (concentrated sample), degradation of beta-carotene was mostly affected by temperature, and less so by light exposure.It was concluded that Ca2+ crosslinked alginic acid nanoparticles were capable of protecting the entrapped beta-carotene from oxidative degradation especially when stored at low temperatures.