Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/4/2015
Publication Date: N/A
Technical Abstract: JUSTIFICATION Electrospinning is a nonthermal process that produces fibers with diameters on the micron- or nano-scales from a polymer solution. If produced by electrospinning of biopolymer solutions, fibrous mats may be created for protecting foods, improving food quality and allowing for the preservation and controlled release of bioactives for health and wellness. However, little information is available on electrospinning of food-grade biopolymers. OBJECTIVE To create fibers for food use from electrospinning aqueous solutions containing calcium (CaCAS), sodium caseinate (NaCAS), or CAS with a polysaccharide, such as Pullulan (PUL), and examine the structure of the fibrous mats created for controlled release of bioactives. METHODOLOGY An electrospinning unit was used to generate the fibers at 50 deg C using from 11 to 23 KV and flow rates from 0.4-3.0 mL/h. The electrospinning apparatus consisted of a syringe pump leading to a needle; a high voltage source at the needle with range from 0 to 50 kV; and, a drum cylinder wrapped in aluminum foil for collection of the fibrous mats. CAS or CAS:PUL solutions were added to the syringe prior to experiments. The morphologies of the fibrous mats were determined using scanning electron microscopy equipped with software to sample 100 of the constituent fibers to calculate mean diameters. RESULTS/DISCUSSION Fibers were not produced by electrospinning 5, 10, or 15% (w/w) aqueous solutions of either CAS, possibly because of little interaction among the CAS, but were produced when the solutions of either CAS were blended with PUL. PUL forms entanglements in solution and served as a carrier for CAS. Electrospinning of neat 15% PUL solutions resulted in fibers with mean diameters of 190 +/- 50 nm while electrospinning of CaCAS:PUL solutions resulted in fibers within the range of pure PUL. This indicated interaction between CaCAS:PUL since larger fibers would be expected if CaCAS was located on the surface of PUL. CONCLUSION This is the first example of CAS nano- and micro-fibers prepared using a polysaccharide carrier, rendering a new dairy product with potential use in food and packaging applications. Electrospinning at temperatures ranging from 25 to 50 deg C preserves the activities of most bioactives embedded in the fibers.