Development and Validation of Rapid Colorimetric Detection of Nitrite Concentration in Meat Products on a Polydimethylsiloxane (PDMS) Microfluidic Device

Fresh sausages are cured meat products that may be contaminated with Staphylococcus aureus during the manufacturing procedure, which is frequently related with inadequate handling practices. The use of nitrite in meat products has proven efficacy against Clostridium botulinum, and studies indicate that bactericidal action against S. aureus depends on factors that are intrinsic and extrinsic to the product. The objective of the present study was to evaluate the effect of nitrite concentration, and pH on S. aureus and psychrotrophic autochthone microbiota in fresh sausages stored at different times and temperatures. Fresh sausage were produced at nitrite concentrations 50, 150 and 200ppm and contaminated with S. aureus. The sausages were storage at refrigeration (7 and 12°C) and the quantification of S. aureus and psychrotrophic microorganisms was carried out on days 0, 2, 4, 7, and 10. Results showed that nitrite concentrations and the temperatures used had minimal effect on the multiplication of S. aureus and psychrotrophic autochthone microbiota. Final counts depended only on the length of storage: at the end of 10 days, counts were statistically similar in the different groups, showing that temperature and nitrite concentrations used did not control microbial growth effectively. It is suggested that the product should be stored below 7°C or at freezing temperatures for greater microbiological stability

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Influence of Turkey Meat on Residual Nitrite in Cured Meat Products

Journal of Food Protection ◽

10.4315/0362-028x-64.2.235 ◽

2001 ◽

Vol 64 (2) ◽

pp. 235-239 ◽

Cited By ~ 9

Author(s):

BIROL KILIC ◽

ROBERT G. CASSENS ◽

LARRY L. BORCHERT

Keyword(s):

Storage Time ◽

Meat Products ◽

Test System ◽

Poultry Meat ◽

Nitrite Concentration ◽

Turkey Meat ◽

Nitrite Level ◽

Cured Meat ◽

Residual Nitrite ◽

Heat Quantity

A response surface experimental design was employed to estimate residual nitrite level at various initial nitrite concentrations, percent turkey meat in the formula, and heat quantity (F) values using a typical wiener as the test system. Pork and mechanically separated turkey were used as the meat ingredients. Residual nitrite and pH were measured at day 1, 7 days, 14 days, and 49 days after processing. Protein, fat, salt, moisture, and CIE (L*a*b*) color values were also determined. Results showed that the effect of turkey meat on residual nitrite level was significant (P < 0.01). An increased amount of turkey meat in the formula resulted in lower residual nitrite levels at a fixed pH. The residual nitrite level was initially proportional to initial nitrite concentration, but it became a nonsignificant factor during longer storage time. Differences in heat quantity had a significant effect (P < 0.05) on residual nitrite level initially. Greater heat quantity decreased residual nitrite level in finished cured meat products at a fixed pH. However, this effect became nonsignificant during longer storage. Reduction of residual nitrite in wieners because of turkey meat addition at a fixed pH was due to characteristics of the turkey tissue, but the mechanism of action remains unknown. It was also established that commercial wieners had a higher pH if poultry meat was included in the formulation.

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Development and validation of a novel microfluidic device for the manipulation of skeletal muscle microvascular blood flow in vivo.

Microcirculation ◽

10.1111/micc.12698 ◽

2021 ◽

Author(s):

Gaylene M Russell McEvoy ◽

Hamza Shogan ◽

Richard J Sové ◽

Graham M Fraser

Keyword(s):

Skeletal Muscle ◽

Blood Flow ◽

Microfluidic Device ◽

Microvascular Blood Flow ◽

Development And Validation

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Microbiological safety of processed meat products formulated with low nitrite concentration — A review

Asian-Australasian Journal of Animal Sciences ◽

10.5713/ajas.17.0675 ◽

2018 ◽

Vol 31 (8) ◽

pp. 1073-1077 ◽

Cited By ~ 8

Author(s):

Soomin Lee ◽

Heeyoung Lee ◽

Sejeong Kim ◽

Jeeyeon Lee ◽

Jimyeong Ha ◽

...

Keyword(s):

Meat Products ◽

Processed Meat ◽

Nitrite Concentration ◽

Microbiological Safety

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Colorimetric detection of solution concentration based on a paper-based microfluidic device

Modern Physics Letters B ◽

10.1142/s0217984918400766 ◽

2018 ◽

Vol 32 (34n36) ◽

pp. 1840076

Author(s):

Liangwei Dong ◽

Yueli Hu ◽

Xiuyu Chen ◽

Xiajun Liu

Keyword(s):

Microfluidic Device ◽

Filter Paper ◽

Printed Circuit Board ◽

Colorimetric Detection ◽

Solution Concentration ◽

Circuit Board ◽

Copper Sheet ◽

Detection Zone ◽

Printed Circuit ◽

True Value

A new method for colorimetric detection of solution concentration is presented. A paper-based microfluidic device was designed and made using printed circuit board technology. Detection zone patterns were designed and transferred to a printed circuit board by hollowing technology. The printed circuit board with patterns was stuck onto a copper sheet. The hollowed zone was filled with solid paraffin and then covered with a piece of filter paper. The paraffin wax was melted by heating the copper sheet and permeated into the filter paper. Solution to be detected was pipetted on the paper-based device with detective zones. The images of the detective zones were obtained using a microscope with charge-coupled device, which is used for calculating RGBI model to further obtain the solution concentration. Litmus was demonstrated in sample experiments. Results showed that maximum error of measured value of solution concentration to its true value is less than 2% using the presented method.

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Simple monitoring of pH and urea in whole blood using wearable smart woman pad

Bioimpacts ◽

10.34172/bi.2021.41 ◽

2020 ◽

Author(s):

Bambang Kuswandi ◽

Nur Andriani ◽

Ari S Nugraha

Keyword(s):

Blood Cell ◽

Microfluidic Device ◽

Red Blood Cell ◽

Whole Blood ◽

Color Change ◽

Clinical Laboratory ◽

Limit Of Detection ◽

Colorimetric Detection ◽

Real Samples ◽

Paper Microfluidic

Introduction: In this work, we used a thread-paper microﬂuidic device (μTPAD) system, where a threaded part for the handling of the whole blood samples and a paper part for the reaction of plasma with immobilized bioreagents integrated into woman pad as a wearable sensing device namely as smart women pad. The μTPAD as a wearable smart woman pad is developed for the detection of pH and urea in mensuration blood as real samples. Methods: This combined device was constructed to cover the elements required, that is, separation of red blood cell, conditioning, analyte reaction, and colorimetric detection. The color change in sensing areas was measured in the RGB values via a smartphone using the Color Grab after a smart woman pad was used. The thread allowed red blood cell sampling and separation, while the paper microﬂuidic device was used for conditioning, biorecognition, and colorimetric transduction of pH and urea as analytes. Results: The time needed for analysis was measured as 110 s using the equilibrium method for both analytes, with a limit of detection (LOD) of 72.55 μg/mL for urea, with precision around 1.68%, while for pH around 0.80%. The smart woman pad allowed rapid detection of pH and urea in menstruation blood as real samples for monitoring of the kidney functions, and the results showed an agreement with the conventional methods that have been generally used in the clinical laboratory. Conclusion: The smart woman pad has the potential to be used as a wearable device to monitor the health status of the user via its blood mensuration analysis.

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