Abstract #W154

# W154
Electrospinning casein-based fibrous mats for food applications.
Peggy M. Tomasula*1, Shih-Chuan Liou2, Ran Li3, Laetitia M. Bonnaillie1, LinShu Liu1, 1USDA/Agricultural Research Service, Eastern Regional Research Service, Dairy and Functional Foods Research Unit, Wyndmoor, PA, 2Chung Shan Medical University, Taichung City, Taiwan 402, 3State Key Laboratory of Hollow Fiber Materials and Processes, School of Materials Science and Engineering, Tianjin Polytechnic University, Tianjin, China.

~~Electrospinning is a process that produces fibrous mats from fibers with diameters on the micron or nano scales from an electrified jet of a polymer solution. If produced by electrospinning biopolymer solutions, the fibrous mats may have the same potential as edible films for protecting foods and improving food quality but also allow for preservation of sensitive nutrients. Electrospinning aqueous solutions of dextran, pullulan (PUL) and gelatin are known to result in homogeneous fibers. However, little information is available on electrospinning other food grade biopolymers. The objective of this study was to create fibers for food use from electrospinning aqueous solutions containing calcium (CaCAS) or sodium caseinate (NaCAS). A nanofiber electrospinning unit was used to generate the fibers at 40°C using voltage of 23 KV and flow rate of 0.5 mL/h. Fibers were not produced by electrospinning 5, 10, or 20% (w/w) solutions of either CAS, possibly because of little interaction among the CAS chains, but were produced when either of the 20% CAS solutions were blended with 15% or 30% (w/w) aqueous solutions of PUL in volume ratios from (2:1) to (1:4), using PUL as a spinnable carrier. 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. Electrospinning 15% PUL solutions resulted in fibers with diameters of 190 ± 50 nm. CaCAS:PUL solutions in volume ratios of (1:1) and (1:2) resulted in fibers with average diameters of 160 ± 40 nm and 1020 ± 600 nm, respectively. NaCAS:PUL solutions in volume ratios of (1:1) and (1:2) resulted in fibers with average diameters of 320 ± 30 nm and 340 ± 150 nm, respectively. The mean diameter of the CaCAS:PUL (1:1) fibers was not significantly different from the pure PUL fibers, but the increase in size of the CaCAS:PUL (2:1) fibers and the NaCAS:PUL(1:1) and (1:2) fiber sizes may stem from changes in hydrogen bonding and thus the degree of entanglement of the PUL chains in the presence of CAS, compared with pure PUL solutions. 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.

Key Words: fibers, nanoscale, polysaccharide