Surface conditioning of stainless steel coupons with skim milk, buttermilk, and butter serum solutions and its effect on bacterial adherence

Microorganisms have been shown to adhere to food-contact surfaces and may provide a route for the contamination of processed food. To better understand this phenomenon, the effects of growth media and surface conditioning on the adherence of Pseudomonas fragi, Salmonella typhimurium and Listeria monocytogenes cells to stainless steel were studied. The microorganisms were grown in tryptic soy broth (TSB), 1% reconstituted skim milk (RSM) and RSM with 1% sucrose (RSM + S). Stainless-steel surfaces were conditioned by immersion in growth media for 1 h and then were rinsed in phosphate-buffered saline (PBS) prior to the adherence assay. After growing in each medium, cells were harvested, resuspended in PBS, and then allowed to contact the stainless steel for 30 min. Adherence was quantified by acridine orange-staining the cells and viewing under epifluorescence microscopy. Growth media had little influence on adherence to stainless steel that had not been preconditioned. P. fragi and L. monocytogenes cells adhered in the highest numbers when grown in RSM plus sucrose. S. typhimurium cells showed the highest level of adherence when grown in TSB. Analysis of variance yielded P values of less than 0.01, indicating that both growth media and surface conditioning were significant in the level of adherence observed.

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Inhibition of bacterial adherence on stainless steel coupons by surface conditioning with selected polar lipids

Journal of Food Safety ◽

10.1111/jfs.12956 ◽

2022 ◽

Author(s):

Nguyen Manh Dat ◽

Thai Minh Phuong ◽

Nguyen Thi Thu ◽

Thai Khanh Phong ◽

Toshitaka Uchino

Keyword(s):

Stainless Steel ◽

Bacterial Adherence ◽

Polar Lipids ◽

Surface Conditioning

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REMOVED: Comparison of Ceramic, Polymeric and Stainless Steel Microfiltration Membranes for the Fractionation of Whey and Casein Proteins from Skim Milk

Procedia Engineering ◽

10.1016/j.proeng.2012.08.768 ◽

2012 ◽

Vol 44 ◽

pp. 1317-1320

Author(s):

O. Glagovskaia ◽

F. Janakievski ◽

K. De Silva

Keyword(s):

Stainless Steel ◽

Skim Milk ◽

Microfiltration Membranes

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Chemical sanitizers to control biofilms formed by two Pseudomonas species on stainless steel surface

Food Science and Technology ◽

10.1590/s0101-20612012005000008 ◽

2012 ◽

Vol 32 (1) ◽

pp. 142-150 ◽

Cited By ~ 13

Author(s):

Danila Soares Caixeta ◽

Thiago Henrique Scarpa ◽

Danilo Florisvaldo Brugnera ◽

Dieyckson Osvani Freire ◽

Eduardo Alves ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Stainless Steel ◽

Biofilm Formation ◽

Skim Milk ◽

304 Stainless Steel ◽

Stainless Steel Surface ◽

Aisi 304 ◽

Pseudomonas Species ◽

Sodium Dichloroisocyanurate ◽

Different Temperatures

The biofilm formation of Pseudomonas aeruginosa and Pseudomonas fluorescens on AISI 304 stainless steel in the presence of reconstituted skim milk under different temperatures was conducted, and the potential of three chemical sanitizers in removing the mono-species biofilms formed was compared. Pseudomonas aeruginosa cultivated in skim milk at 28 °C presented better growth rate (10.4 log CFU.mL-1) when compared with 3.7 and 4.2 log CFU.mL-1 for P. aeruginosa and P. fluorescens cultivated at 7 °C, respectively. Pseudomonas aeruginosa formed biofilm when cultivated at 28 °C. However, only the adhesion of P. aeruginosa and P. fluorescens was observed when incubated at 7 °C. The sodium dichloroisocyanurate was the most efficient sanitizer in the reduction of the adhered P. aeruginosa cells at 7 and 28 °C and those on the biofilm, respectively. The hydrogen peroxide was more effective in the reduction of adhered cells of P. fluorescens at 7 °C.

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Evaluation of a Recirculating Dipper Well Combined with Ozone Sanitizer for Control of Foodborne Pathogens in Food Service Operations

Journal of Food Protection ◽

10.4315/0362-028x.jfp-16-055 ◽

2016 ◽

Vol 79 (9) ◽

pp. 1537-1548 ◽

Cited By ~ 6

Author(s):

GISELLE ALMEIDA ◽

KRISTEN E. GIBSON

Keyword(s):

Stainless Steel ◽

Exposure Time ◽

Service Industry ◽

Control Point ◽

Food Service ◽

Skim Milk ◽

Extended Period ◽

E Coli ◽

Critical Control Point ◽

Retail Food

ABSTRACT In the retail food service industry, small countertop sinks, or dipper wells, are utilized to rinse and store serving utensils between uses. These dipper wells are designed to operate under a constant flow of water, which serves both to prevent the accumulation of microorganisms and to aid in the cleanliness of the dipper well itself. Here, a recirculating dipper well ozone sanitation system (DWOSS) was evaluated for the control and inactivation of Escherichia coli, Listeria innocua, PRD1 bacteriophage, and Staphylococcus aureus present on a stainless steel disher. In a low ozone (O3) demand medium, the DWOSS achieved over a 5-log reduction for E. coli, L. innocua, and PRD1 at 30 s when exposed to 0.45 to 0.55 ppm of residual O3. A greater than 5-log total CFU reduction was achieved for S. aureus at a 600-s exposure time and 0.50 ppm of residual O3. When evaluated in the presence of high O3 demand medium (10% skim milk), the DWOSS performed significantly better (P < 0.05) for all microbe–exposure time combinations compared with a conventional dipper well with respect to the reduction of microbes on the stainless steel disher. For example, at 30 s, the DWOSS achieved 4.37, 2.48, 1.38, and 1.31 greater log (CFU or PFU) reduction of E. coli, L. innocua, PRD1, and S. aureus, respectively, than a conventional dipper well. In addition, the DWOSS was evaluated under two neglect scenarios to determine its ability to control microbes in 10% skim milk medium on the stainless steel disher and within the dipper well basin itself over an extended period of use (2 h of use per day over 5 days). Considering the efficacy of the DWOSS unit against the microbes evaluated here, the integration of ozone into a dipper well could be a potential critical control point to reduce the incidence of microbial contamination during retail food service. To our knowledge, a dipper well with a cleaning-in-place sanitizing system is not currently available for use in the food service industry; and, thus, this is the first study to evaluate the efficacy of a cleaning-in-place dipper well.

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SURFACE CONDITIONING OF CARDIOVASCULAR 316L STAINLESS STEEL STENTS: A REVIEW

Surface Review and Letters ◽

10.1142/s0218625x17300027 ◽

2016 ◽

Vol 24 (01) ◽

pp. 1730002 ◽

Cited By ~ 2

Author(s):

LUCILA NAVARRO ◽

JULIO LUNA ◽

IGNACIO RINTOUL

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

316L Stainless Steel ◽

Abrupt Change ◽

Outer Part ◽

Ion Release ◽

Aisi 316L Stainless Steel ◽

Surface Conditioning ◽

Physical Chemical ◽

Review Reports

Cardiovascular disease is the leading cause of death worldwide and 90% of coronary interventions consists in stenting procedures. Most of the implanted stents are made of AISI 316L stainless steel (SS). Excellent mechanical properties, biocompatibility, corrosion resistance, workability and statistically demonstrated medical efficiency are the reasons for the preference of 316L SS over any other material for stent manufacture. However, patients receiving 316L SS bare stents are reported with 15–20% of restenosis probability. The decrease of the restenosis probability is the driving force for a number of strategies for surface conditioning of 316L SS stents. This review reports the latest advances in coating, passivation and the generation of controlled topographies as strategies for increasing the corrosion resistance and reducing the ion release and restenosis probability on 316L SS stents. Undoubtedly, the future of technique is related to the elimination of interfaces with abrupt change of properties, the elimination of molecules and any other phase somehow linked to the metal substrate. And leaving the physical, chemical and topographical smart modification of the outer part of the 316L SS stent for enhancing the biocompatiblization with endothelial tissues.

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Investigation on the cold temperature retention capacity of the 1.5 Liter Thermos® double wall vacuum stainless steel thermal container when filled to different volumes and with different types of milk

BCIT Environmental Public Health Journal ◽

10.47339/ephj.2015.126 ◽

2015 ◽

Author(s):

Jocelyn Wu ◽

BCIT School of Health Sciences, Environmental Health ◽

Helen Heacock

Keyword(s):

Stainless Steel ◽

Skim Milk ◽

Cold Temperature ◽

Data Logger ◽

Chi Square ◽

Retention Capacity ◽

Danger Zone ◽

Different Types ◽

Chi Square Test ◽

Double Wall

Introduction: Customers sometimes question the freshness of milk inside thermal containers in coffee shops. Milk that is kept between 4°C to 60°C can support the growth of pathogens, hence it should be kept below 4°C. Thermal containers are often advertised as being able to retain the temperature of their contents for a prolonged period of time. Yet, the extent of their temperature retention capacity is not clearly defined by the manufacturers. This study investigated the effectiveness of the 1.5 Liter Thermos® Double Wall Vacuum Stainless Steel Serving Carafe thermal container in keeping milk at ≤4°C when it was filled to different volumes and with different types of milk over a nine hour period. Methods: Four tests were carried out in this study: The 1.5L Skim Milk, The 1.5L Creamo, The 0.75L Skim Milk and The 0.75L Creamo Test. For each test, the milk was placed into the 1.5L Thermos® Double Wall Vacuum Stainless Steel Serving Carafe with the initial temperature between 3.1°C to 3.4°C. Change in temperature was recorded for nine hours using the Thermocouple data logger. Results: The descriptive data demonstrates that the mean temperatures over the nine-hour period for The 1.5L Skim Milk Test, The 1.5L Creamo Test, The 0.75L Skim Milk Test and The 0.75L Creamo Test were 4.41±0.88°C, 4.51±0.95°C, 5.59±1.52°C and 6.05±1.77°C, respectively. MANOVA results suggested that “volume”, “time”, “type of milk”, “volume and time”, “volume and type of milk”, “time and type of milk”, and “volume, time and type of milk” did have effects on the temperature retention capacity of the thermal container with p-values <0.05. The temperatures of all samples were <4°C at hour zero. All of the samples’ temperatures began to increase once they were inside the thermal container and all of the samples entered the danger zone (>4°C) after four hours. A Chi Square test was conducted to determine whether Creamo or skim milk was safer (≤4°C) from hour one to four. Results showed that 123/240 (51%) skim milk and 110/240 (46%) Creamo samples were safe, but the result was not statistically significant. Conclusion: This study’s results indicate that the tested thermal container had a better cold temperature retention capacity when it was filled up (1.5L) compared to when it was only half filled (0.75L). In addition, when the thermal container was filled with skim milk, it also had a better cold temperature retention capacity compared to Creamo. Finally, this specific thermal container was not successful in maintaining the temperature of milk out of the danger zone (≤4°C) after four hours. These results should be disseminated to Environmental Health Officers whose job it is to keep the public safe from foodborne illnesses. As well, policies should be established pertaining to time permitted to keep milk in thermal containers.

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The influence of pre-vacuum surface conditioning on the response with electron stimulated desorption at stainless steel surfaces in uhv

Vacuum ◽

10.1016/s0042-207x(80)80050-9 ◽

1980 ◽

Vol 30 (2) ◽

pp. 91-92 ◽

Cited By ~ 3

Author(s):

D Bhasavanich ◽

E.M. Williams

Keyword(s):

Stainless Steel ◽

Surface Conditioning ◽

Steel Surfaces ◽

Electron Stimulated Desorption

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Evaluation of Asparagine in the AOAC Use-Dilution Method

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/69.6.1003 ◽

1986 ◽

Vol 69 (6) ◽

pp. 1003-1005

Author(s):

Eugene C Cole ◽

William A Rutala

Keyword(s):

Stainless Steel ◽

Bacterial Adherence ◽

Dilution Method ◽

And Storage

Abstract An asparagine solution (0.1%) is required in the AOAC use-dilution method to cover stainless steel carriers during sterilization and storage. The rationale for using an asparagine soak is unclear. It has been proposed that asparagine enhances bacterial adherence to carriers or inhibits corrosion of the metal carriers or both. The former theory was assessed in this study by comparing bacterial adherence on seeded carriers stored in 0.1 and 1% asparagine solution to those stored dry or in water. The anticorrosive properties of asparagine on stainless steel carriers were microscopically evaluated after 9 months. The results demonstrate that asparagine neither enhances bacterial adherence to carriers nor is necessary to prevent corrosion.

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