Submitted to: LWT - Food Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/11/2015
Publication Date: 2/19/2015
Citation: Liu, S.X., Singh, M., Wayman, A.E., Hwang, H.-S., Fhaner, M. 2015. Reduction of omega-3 oil oxidation in stable emulsion of caseinate-omega-3 oil-oat beta-glucan. LWT - Food Science and Technology. 62:1083-1090.
Interpretive Summary: This research demonstrated that it was possible to develop heart-healthy beverage products that contain omega-3 oil and soluble oat beta-glucan with good shelf life stability and oxidative stability. Blending and homogenization of milk protein such as caseinate, 10% omega-3 oils (plant or marine based) and dietary fiber such as oat gum comprised of (up to 97%) beta-glucan gives stable emulsions that may have potential application in healthy functional food and beverage markets ranging from grab-n-go meal alternatives to sports recovery beverages. This type of beverage emulsion concentrate may be further diluted to be incorporated into carbonated soft drinks (non-cola products). This work provides a new approach to develop functional food products in order to tackle the persistent American dietary challenge and its dreadful health and fiscal consequences.
Technical Abstract: Lipid oxidation, particularly oxidation of unsaturated fatty acids such as omega-3 fatty acids, has posed a serious challenge to the food industry trying to incorporate heart-healthy oil products into their lines of healthful foods and beverages. In this study, heart healthy plant and marine based omega-3 oils were dispersed into sodium caseinate dispersion and then mixed with heart-healthy oat gum that was later purified to be comprised of 97% ß-glucan in a homogenizer under room temperature. The stable emulsions underwent shelf life tests to assess their stabilities and oxidative activities. The objective of this study was to see if the complexes formed between ß-glucan in oat gum and oil encapsulated caseinate micelles will protect omega-3 oil from oxidation without causing physical stability issue in healthy beverage formulations. Various preparations of omega-3 oil-in-water emulsions with 10% oil (vol/vol) stabilized with sodium caseinate ranging from 0% to 3% (w/w) and ß-glucan ranging from 0% to 0.3% (w/w) were formed. The formulations were stabilized using a Panda homogenizer for 30 min after initial 2-minute mixing with a blender. The physical properties such as creaming index, particle size, and viscosity of the emulsion preparations were measured. The lipid oxidation was measured as lipid hydroperoxide concentration and the reduction of lipid oxidation was observed under shelf-life stress tests at 28 oC. The fatty acids of the oils were also measured using gas chromatography (GC). Omega-3 fatty acids compositional changes were observed over the shelf life tests. It was found that caseinate helped reduce the oxidation of the oils in general and there is no impact of ß-glucan on oxidation. Addition of caseinate and ß-glucan in the emulsions increased both particle size and viscosity but the increases in both appear to be minor.