ISOLATION OF SALMONELLAE FROM NATURALLY CONTAMINATED DRIED MILK PRODUCTS

1971 ◽  
Vol 34 (8) ◽  
pp. 389-393 ◽  
Author(s):  
Bibek Ray ◽  
J. J. Jezeski ◽  
F. F. Busta

Eight plants that were equipped with several types of driers and that produced a variety of dried milk products were surveyed for Salmonella contamination. Each plant had a history of Salmonella isolations from finished product. Sampling included production fractions as well as tailings and environmentals. Distribution of salmonellae was not random in fractions of product obtained during a day's operation. One-fourth of the 277 samples of the first product through the system (animal feed) contained salmonellae; this was a higher frequency than the 5.6% positive tests observed in 963 samples of other fractions produced later during daily operation. The incidence of Salmonella isolations in these food-grade products also was lower than that observed in 873 tailings samples (10.5%), in 1125 air filter samples (23.6%), and in 763 environmental samples (21.1%). However, plants with Salmonella-positive air filters or environmentals were able, on occasion, to manufacture product free of salmonellae. Results of this study indicated that the first product out of the system during daily operation provides the best sample for evaluation of product contamination by salmonellae.

Author(s):  
Floor Haalboom

This article argues for more extensive attention by environmental historians to the role of agriculture and animals in twentieth-century industrialisation and globalisation. To contribute to this aim, this article focuses on the animal feed that enabled the rise of ‘factory farming’ and its ‘shadow places’, by analysing the history of fishmeal. The article links the story of feeding fish to pigs and chickens in one country in the global north (the Netherlands), to that of fishmeal producing countries in the global south (Peru, Chile and Angola in particular) from 1954 to 1975. Analysis of new source material about fishmeal consumption from this period shows that it saw a shift to fishmeal production in the global south rather than the global north, and a boom and bust in the global supply of fishmeal in general and its use in Dutch pigs and poultry farms in particular. Moreover, in different ways, the ocean, and production and consumption places of fishmeal functioned as shadow places of this commodity. The public health, ecological and social impacts of fishmeal – which were a consequence of its cheapness as a feed ingredient – were largely invisible on the other side of the world, until changes in the marine ecosystem of the Pacific Humboldt Current and the large fishmeal crisis of 1972–1973 suddenly changed this.


Author(s):  
Hong Qian ◽  
Ying Fang ◽  
Kao Wu ◽  
Hao Wang ◽  
Bin Li ◽  
...  

Abstract This study presents two methods to improve the air filtration performance of konjac glucomannan (KGM)-based aerogel air filters through physical structure design by changing the pore-size distribution and the surface area, using an air purifier. Results indicated that KGM-based aerogels had a comparable filtration effect with the commercial air filter with a longer purification time. This purification time could be shortened by over 50%, by changing the pore-size distribution from large size to small size or increase the surface area with the fold structure. This should boost the development of polysaccharide-based aerogel used as the air filter.


2021 ◽  
Vol 11 (9) ◽  
pp. 3831
Author(s):  
Han-Jung Kim ◽  
Dong-In Choi ◽  
Sang-Keun Sung ◽  
Su-Han Lee ◽  
Sang-Jin Kim ◽  
...  

Due to the increasing use of polypropylene-based nonwoven dust masks and air filters, environmental problems that occur due to the plastic pollution resulting from the disposal of these materials have also increased. Hence, an eco-friendly air filter based on PVA nanofibers (NFs) was fabricated by electrospinning on a nonwoven fabric, and its performance was evaluated as a filter capable of blocking or capturing particulate matter. The quality factor of the optimized PVA NF-based air filter was found to be 0.010606 Pa−1, which is lower than that of a HEPA filter (0.015394 Pa−1), but higher than that of a cabin air filter (0.010517 Pa−1) and a dust mask (0.009102 Pa−1). The contamination level of the PVA NF-based filter was analyzed by optical and structural analyses of the filter surface. Finally, the filter was soaked in water to selectively remove the contaminated PVA NF layer, and the remaining nonwoven fabric was able to be reused to make the filter.


2008 ◽  
Vol 74 (19) ◽  
pp. 5913-5917 ◽  
Author(s):  
N. Mullane ◽  
B. Healy ◽  
J. Meade ◽  
P. Whyte ◽  
P. G. Wall ◽  
...  

ABSTRACT The microbial contamination of air filters and possible links to contaminated product in a powdered milk protein-processing facility were investigated. Over a 10-month period, seven air filters, the environment, and powdered product were analyzed for the presence of Cronobacter spp. The effects of air filter installation, maintenance, and subsequent dissemination of Cronobacter were investigated. A total of 30 isolates were characterized by pulsed-field gel electrophoresis (PFGE). PFGE revealed the presence of three clonal populations distributed throughout the manufacturing site. This study highlights the need for proper installation of air filters to limit the dissemination of microorganisms into processing sites.


2011 ◽  
Vol 59 (11) ◽  
pp. 6064-6070 ◽  
Author(s):  
Xiangmei Li ◽  
Pengjie Luo ◽  
Shusheng Tang ◽  
Ross C. Beier ◽  
Xiaoping Wu ◽  
...  

2018 ◽  
Vol 67 ◽  
pp. 03016 ◽  
Author(s):  
A.A.I.A.S. Komaladewi ◽  
K. Khoiruddin ◽  
I.W. Surata ◽  
I.D.G.A. Subagia ◽  
I.G. Wenten

The worsening air quality has become an environmental issue since it has a serious effect on human health. This is generally attributed to airborne particles including various pathogens and others fine particles. Even though air filters show excellent removal efficiency towards pathogens, the captured microorganism can remain viable in the filter, grow, and re-suspended into an air stream resulting in a secondary source of pollutants. Considerable studies have been conducted to develop air filters which also have antibacterial properties for solving this issue. Results of several studies showed that air filters with antimicrobial activities have been successfully prepared by incorporating inorganic nanoparticles and natural plant extracts. With antibacterial properties, the air filters may be potentially used to control air quality, particularly for indoor spaces e.g. hospitals, by removing fine particles and inhibiting microorganism. In this paper, the recent development of antimicrobial air filter is reviewed. In addition, preparation and performance of developed antimicrobial filters are discussed. Prospects and challenges of antimicrobial air filter are also pointed out.


2020 ◽  
Vol 10 (24) ◽  
pp. 9120
Author(s):  
Ha Ram Byun ◽  
Seon Young Park ◽  
Ee Taek Hwang ◽  
Byoung In Sang ◽  
Jiho Min ◽  
...  

Antimicrobial air filters are required to protect humans from the risk of secondary bioaerosol pollution as well as airborne particles. Three plant extracts (tea-tree oil, rosemary, and garlic) were selected to replace antimicrobial chemicals in air filters. The antimicrobial activity of plant extracts was investigated using Micrococcus luteus and Escherichia coli. Phytochemicals present in the three plant extracts were identified using a gas chromatograph coupled with a mass spectrometer. The extracts were spray-coated on polyethylene terephthalate filter surfaces using silicate polymeric coating and evaluated via X-ray photoelectron spectroscopy and a scanning electron microscope with energy dispersive spectroscopy. After coating, an increase of 9.1% in the pressure drop was observed. The strain Micrococcus luteus was used to evaluate the antimicrobial activity of the air filter. After bioaerosol exposure, the tea-tree oil-coated filters immediately induced M. luteus cell inactivation (40–55%), whereas the rosemary and garlic coated filters did not. However, 48 h after exposure, a significant M. luteus inactivation of 99.99%, 99.0%, and 99.9% was recorded for concentrations of 2.89, 6.73, and 11.51 mg/cm2 for the tea-tree, rosemary, and garlic extracts, respectively. The coated filters exhibited high antimicrobial activity, thereby indicating significant potential for application as self-cleaning air filters.


1971 ◽  
Vol 34 (9) ◽  
pp. 423-427 ◽  
Author(s):  
Bibek Ray ◽  
J. J. Jezeski ◽  
F. F. Busta

Qualitative tests for the presence of salmonellae in naturally contaminated dried milk products and tailings obtained from five plants indicated rapid decreases in numbers of positive samples. After storage of up to 10 months, <23% of the 49 product samples and <36% of the 93 tailings samples exhibited viable salmonellae. In product fractions of daily production, storage survival was greatest in the first product through the system (48.9%) when compared to an average of 23% survival in the food grade fractions. Quantitative determinations of salmonellae in nine samples indicated a significant reduction from 2.2 to 0.9 Most Probable Number per 100 g sample. These data indicated that samples which contained viable salmonellae immediately after manufacture might test negative after extended storage. However, extended storage did not free all samples of contamination. Therefore, storage cannot be based as a method of freeing contaminated dried milk products of salmonellae.


Small ◽  
2017 ◽  
Vol 13 (11) ◽  
Author(s):  
Xinglei Zhao ◽  
Yuyao Li ◽  
Ting Hua ◽  
Pan Jiang ◽  
Xia Yin ◽  
...  
Keyword(s):  

Author(s):  
Sang Bin Jeong ◽  
Ki Joon Heo ◽  
Byung Uk Lee

We developed an antimicrobial air filter using natural sea salt (NSS) particles. Airborne NSS particles were produced via an aerosol process and were continuously coated onto the surface of an air filter under various deposition times. The filtration efficiency and bactericidal performance of the NSS-coated filter against aerosolized bacterial particles (Staphylococcus epidermidis, Escherichia coli) were evaluated quantitatively. The filtration efficiency of the tested filter ranged from 95% to 99% depending on the deposition time, and the bactericidal performance demonstrated efficiencies of more than 98% against both tested bacterial bioaerosols when the NSS deposition ratio was more than 500 μg/cm2. The experimental results indicated that the NSS-coated filters have the potential to be used as effective antimicrobial air filters for decreasing environmental exposure to microbial contaminants.


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