Air-cleaning System Effectiveness for Control of Airborne Microbes in a Meat-processing Plant

ABSTRACT: :
The effectiveness of duct-mounted and console wall-mounted germicidal air cleaning units on the reduction of airborne microbes was determined. Preliminary air samples were collected and airborne bacteria and molds were monitored over time in the retail sales room, processing room, aging cooler and chill cooler of the Auburn Univ. Meat Laboratory. Log₁₀ cfu/m³ bacteria and molds were not reduced by filtration of fresh air in the air duct of the sales room(P > 0.05). After at least 18 h of filtration, 3 or 4 console filtration units operated simultaneously were effective (P ≤ 0.05) at reducing airborne bacteria and molds under controlled conditions in the processing room, aging cooler, and chill cooler. Three console filtration units reduced (P ≤ 0.05) airborne molds under production conditions in the processing room. These data suggest that an electrostatically polarized filter medium combined with scanning UV light is effective in reducing airborne microorganisms in a small processing plant.     

基于静电纺PAN/PMIA共混纳米纤维复合空气过滤纸的制备及性能研究

以空气过滤原纸为基材,高可纺性的聚丙烯腈（PAN）和高性能间位芳纶短切纤维（PMIA）为原料,利用静电纺丝技术,制备PAN/PMIA共混纳米纤维复合空气过滤纸。通过调整2种特种纤维的质量比,制备具有良好过滤性能和较好耐高温性能的复合空气过滤纸。结果表明,PAN与PMIA质量比为3∶7的PAN/PMIA共混纳米纤维复合空气过滤纸的过滤效率为99.995%,初始阻力为79.01 Pa,容尘量为175 g/m²。经一系列热处理后,复合空气过滤纸的过滤效率可保持在99.960%以上。     

Phenolic profile,antioxidants, and sensory acceptance of bioactive-enhanced peanuts using ultrasound and UV

Phenolic antioxidant compounds, including resveratrol, are associated with reduced risk of cancer and cardiovascular disease, and delayed ageing. This study aims to quantify synergistic enhancement of phenolics and antioxidants in peanuts by combinations of ultrasound (US)–UV treatments, compared to either US or UV, and determine optimum parameters for combined US–UV process. LC–MS confirmed the bioactive phenolics: trans-resveratrol, trans-piceid, and p-coumaric-, caffeic-, and ferulic-acids, which achieved maximum increases, with combined US–UV, compared to US or UV; as did total phenolics (TP), TEAC, and ORAC. Optimum parameters for a combined US–UV process will provide up to 4.8 μg/g trans-resveratrol, 170 μg/g p-coumaric acid, and 150 μM TE/g ORAC or >100% that found in red wines; 1.0 μg/g trans-piceid, 2.6 μg/g ferulic acid, 1.48 mg GAE/g TP, and consumer acceptance ?5. Optimum combined US–UV resulted in 1.3× or 2.3× the trans-resveratrol concentrations in US or UV, respectively, suggesting synergistic effect of UV and US in enhancing resveratrol in peanuts.     

Development of colour and firmness in strawberry crops is UV light sensitive, but colour is not a good predictor of several quality parameters

BACKGROUND: Strawberry ( Fragaria × ananassa Duchesne var. Elsanta) plants were grown in polytunnels covered with three polythene films that transmitted varying levels of ultraviolet (UV) light. Fruit were harvested under near‐commercial conditions and quality and yield were measured. During ripening, changes in the colour parameters of individual fruit were monitored, and the accuracy of using surface colour to predict other quality parameters was determined by analysing the correlation between colour and quality parameters within UV treatments. RESULTS: Higher exposure to UV during growth resulted in the fruit becoming darker at harvest and developing surface colour more quickly; fruit were also firmer at harvest, but shelf life was not consistently affected by the UV regime. Surface colour measurements were poorly correlated to firmness, shelf life or total phenolics, anthocyanins and ellagic acid contents. CONCLUSION: Although surface colour of strawberry fruits was affected by the UV regime during growth, and this parameter is an important factor in consumer perception, we concluded that the surface colour at the time of harvest was, contrary to consumer expectations, a poor indicator of firmness, potential shelf life or anthocyanin content. Copyright © 2011 Society of Chemical Industry     

Characterisation of vitamin B12 immunoaffinity columns and method development for determination of vitamin B12 in a range of foods,juices and pharmaceutical products using immunoaffinity clean-up and high performance liquid chromatography with UV detection

New rapid and simpler procedures, using immunoaffinity columns, have been developed for the determination of vitamin B12 in a range of samples including three different US National Institute of Standard and Technology (NIST) Reference Materials, infant formula, powdered energy drinks and bars, wheat breakfast cereal, carbonated soft drinks, fruit juices and vitamin B12 tablets. The procedures involved extraction of vitamin B12 using water or sodium acetate buffer and enzyme digestion (using pepsin or α-amylase, or both) if necessary. The extract was clarified and passed through “EASI-EXTRACT® Vitamin B12”, an immunoaffinity column containing monoclonal antibody with high affinity and specificity to vitamin B12. Subsequently, the vitamin B12 immunoaffinity column was washed with 10 ml water and the vitamin B12 was released from the column with 3 ml methanol. Following evaporation, the samples were reconstituted in mobile phase and analysed by HPLC–UV at 361 nm on an ACE 3AQ analytical column using a gradient elution consisting of 0.025% trifluoroacetic acid in water and acetonitrile. Analysis of three types of NIST Standard Reference Materials in triplicate demonstrated the results of the immunoaffinity column method were comparable to microbiological assay results. Method repeatability was determined for all samples analysed and ranged between 0.8 and 10%, demonstrating the method was repeatable with complex matrices (NIST 2383) containing low levels of vitamin B12 (0.44 μg per 100 g), as well as simpler matrices, such as vitamin tablets containing high levels (2000 μg per 0.849 g) of vitamin B12.