Ultraviolet treated liquid porcine plasma and spray dried to powder form maintained product quality

Spray dried plasma (SDP) is a feed ingredient included in pig starter diets. Numerous scientific papers and extensive review papers document significant improvement in post weaning performance and its safety when SDP is included in weaning feed. Ultra violet light at 254 nm (UV-C) kills many microorganisms including bacteria and viruses. Treatment of human plasma fractions with UV-C has been effective in inactivation of many model viruses and both Gram negative and Gram positive bacteria. The objective was to evaluate the effect of a unique UV-C reaction system designed for processing opaque liquids in the production of porcine SDP and its impact on total aerobic plate count (TPC) and typical quality parameters.

Two commercial production runs were completed. The first run included the processing of 3 truckloads (~22,700 L each) porcine plasma collected at different commercial abattoirs on 3 different days. The liquid plasma was treated with UV-C at a rate of 2,836J/L, concentrated and spray dried. This would represent a partial-day production. The second run comprised processing 9 truckloads of porcine plasma obtained from different collection sites representing a typical full-day production. The porcine plasma was UV-C treated with 2,853J/L, concentrated and spray-dried. Plasma for both runs met all product quality specifications for commercial plasma and with the exception of UV-C treatment was processed consistent with normal production SOP’s. Samples were analyzed for viral genome by PCR (PEDV, PCV2, PRRS, PPV, and Deltacoronavirus), TPC, pH, protein, solids, ash, and porcine IgG. Samples were submitted to a commercial lab for TPC, PCR analysis was conducted at Iowa State Diagnostic Lab, while other analysis was conducted by the Quality Assurance lab at APC. The Reynolds number was determined to assure turbulent flow was maintained through the UV-C reactor. Analysis of the UV-C treated SDP was compared to typical values for commercially produced SDP.

UV-C treatment reduced TPC 3 log in liquid plasma and more than 2 log reduction compared to untreated commercial powder plasma. UV-C treated plasma met all specifications for commercial plasma. UV-C treatment did not affect PCR analysis for the viruses that were evaluated.

These tests demonstrate that UV-C treatment of liquid plasma effectively reduces TPC. Further, UV-C treatment of liquid plasma does not affect other quality parameters of SDP. The addition of UV-C treatment is an effective redundant safety step in the commercial production of SDP.

Disclosure of Interest: J. Campbell Conflict with: Employee, J. Polo Conflict with: Employee.