Combined effects of spray-drying conditions and postdrying storage time and temperature on Salmonella choleraesuis and Salmonella typhimurium survival when inoculated in liquid porcine plasma

Inactivation of African swine fever virus inoculated in liquid plasma by spray drying and storage for 14 days at 4°C or 20°C

African swine fever virus (ASFV) is a dsDNA virus that can cause high mortality in pigs of all ages. Spray-dried porcine plasma (SDPP) is a highly digestible ingredient used in feed because it benefits performance, gut function and immunity. The objectives were to test if the spray-drying (SD) conditions along with post-drying storage of product for 14 days can inactivate ASFV inoculated in liquid plasma. Fresh liquid porcine plasma was inoculated with ASFV (BA71V) to a final concentration of 105.18 ±0.08 TCID50/mL of liquid plasma. Triplicate 2-L samples of spiked plasma were SD in a lab drier set at an outlet temperature of 80°C or 71°C. The final dried samples were stored at 4°C or 20°C for 14 d. Liquid and SD samples were analyzed for ASFV infectivity in two mirror 24-well plaques containing VERO cells monolayers. Wells were inoculated with different dilutions of SDPP dissolved 1:9 in PBS. One plaque was immediately frozen at -80°C and the other was incubated at 37°C for 3 d. Each dilution was replicated 9 times. After incubation both plaques were analyzed for ASFV by qRT-PCR. Results indicated that the SD process inactivated between 3.2 to 4.2 Logs ASFV TCID50/mL and 2.53 to 2.75 Logs TCID50/mL when the outlet temperature were 80°C and 71°C respectively. All SD samples stored at 4°C or 20°C for 14 d were absent of infectious ASFV. The combination of SD and post drying storage at both temperatures for 14 d was able to inactive >5.18 ±0.08 Log10 of ASFV inoculated in liquid porcine plasma, demonstrating that the manufacturing process for SDPP can be considered safe regarding ASFV.

Optimization of Astaxanthin Recovery in the Downstream Process of Haematococcus pluvialis

Astaxanthin derived from Haematococcus pluvialis is a valuable metabolite applied in a wide range of products. Its extraction depends on a sophisticated series of downstream process steps, including harvesting, disruption, drying, and extraction, of which some are dependent on each other. To determine the processes that yield maximum astaxanthin recovery, bead milling, high-pressure homogenization, and no disruption of H. pluvialis biomass were coupled with spray-drying, vacuum-drying, and freeze-drying in all possible combinations. Eventually, astaxanthin was extracted using supercritical CO2. Optimal conditions for spray-drying were evaluated through the design of experiments and standard least squares regression (feed rate: 5.8 mL/min, spray gas flow: 400 NL/h, inlet temperature: 180 °C). Maximal astaxanthin recoveries were yielded using high-pressure homogenization and lyophilization (85.4%). All combinations of milling or high-pressure homogenization and lyophilization or spray-drying resulted in similar recoveries. Bead milling and spray-drying repeated with a larger spray-dryer resulted in similar astaxanthin recoveries compared with the laboratory scale. Smaller astaxanthin recoveries after the extraction of vacuum-dried biomass were mainly attributed to textural changes. Evaluation of these results in an economic context led to a recommendation for bead milling and spray-drying prior to supercritical CO2 extraction to achieve the maximum astaxanthin recoveries.

Effect of spray-drying and ultraviolet C radiation as biosafety steps for CSFV and ASFV inactivation in porcine plasma

Spray-dried animal plasma (SDAP) is widely used in diets of domestic animals to improve health status and increase growth and feed efficiency. Individual steps in the SDAP manufacturing process, including spray-drying, have been validated to inactivate potential pathogens. Manufacturing standards have established a minimum exit temperature of 80°C and a minimum post-drying storage period of 14 days at 20°C for production of SDAP. Also, UV-C irradiation has been evaluated as another inactivation step that could be included in the manufacturing process. The aim of this study was to assess the inactivation effectiveness of spray-drying on Classical swine fever virus (CSFV) and African swine fever virus (ASFV) and the effect of UV-C inactivation on ASFV as redundant biosafety steps of the manufacturing process for producing spray-dried porcine plasma (SDPP). This study demonstrated that UV-C treatment of liquid porcine plasma can inactivate more than 4 Log10 TCID50/mL of ASFV at 3000 J/L. Spray-drying effectively inactivated at least 4 Log10 TCID50/mL of both CSFV and ASFV. Incorporating UV-C technology within the SDAP manufacturing process can add another biosafety step to further enhance product safety.

Biosafety steps in the manufacturing process of spray-dried plasma: a review with emphasis on the use of ultraviolet irradiation as a redundant biosafety procedure

Spray dried plasma (SDP) is a functional protein source obtained from blood of healthy animals, approved by the veterinary authorities from animals declared to be fit for slaughter for human consumption. Blood of these animals is collected at the slaughterhouse, treated with an anticoagulant, chilled and transported to industrial facilities in which blood is centrifuged to separate the red blood cells from the plasma fraction. Plasma is then concentrated, and spray dried at high temperatures (80 °C throughout its substance) to convert it in a powder. Such method preserves the biological activity of its proteins, mainly albumins and globulins. SDP is mainly used in pig feed diets to significantly improve daily gain, feed intake, production efficiency, and to reduce post-weaning lag caused by the appearance of post-weaning diarrhea. Although SDP is considered a safe product and its manufacturing process consists of several biosafety steps, the security of the SDP is often questioned due to its nature as raw blood by-product, especially when emergent or re-emergent pathogens appear. This review provides an evaluation and validation of the different safety steps present in the manufacturing process of SDP, with special focus on a new redundant pathogen inactivation step, the UV-C irradiation, that may be implemented in the manufacturing process of the SDP. Overall results showed that the manufacturing process of SDP is safe and the UV-C radiation was effective in inactivating a wide range of bacteria and viruses spiked and naturally present in commercially collected liquid animal plasma and it can be implemented as a redundant biosafety step in the manufacturing process of the SDP.

The Canadian 2014 porcine epidemic diarrhoea virus outbreak: Important risk factors that were not considered in the epidemiological investigation could change the conclusions

The introduction and spread of porcine epidemic diarrhoea virus (PEDV) in North America resulted in significant death loss in the swine industry. As the industry learned how to manage this disease, many new risks were identified, including the potential for feed and feed ingredients to become contaminated and spread PEDV. In addition, biosecurity practices were reevaluated and strengthened throughout the industry. At the time of the outbreak epidemiologists did not understand, as well as they are understood today, all the risk factors that contribute to the spread of PEDV. As a result, the epidemiological investigations into the 2014 PEDV outbreak in eastern Canada may not have investigated all risk factors as thoroughly as they would be investigated today. In retrospect, many of the Bradford Hill criteria used to determine causation were not fulfilled. This review identifies risk factors that were not included in the 2014 epidemiology. If these risk factors were included in the epidemiology, the conclusions and determination of causation may have been different.