Verifying Correct Sanitizer and Detergent Concentrations in Cleaning
Part vi and vii Reference Methods to confirm the correct concentrations of detergents and sanitizers and the responsibility & methods used to verify the effectiveness of the cleaning and sanitation.
What can we do to confirm correct concentrations?
To confirm the correct concentrations of detergents and sanitizers, we use a combination of validated methods including test strips or colorimetric kits for quick checks (e.g., chlorine, quat, peracetic acid), titration kits for more precise measurement of cleaners, and digital meters such as ORP or conductivity meters where applicable. These methods are matched to the specific chemical in use and follow manufacturer guidelines. We also routinely verify and calibrate our chemical dispensing systems to ensure accuracy. The sanitation team is responsible for preparing and applying the solutions correctly, while the QA team conducts independent verification and documentation. Effectiveness of cleaning and sanitation is confirmed through visual inspections, ATP testing, allergen and protein residue swabs, and microbiological surface testing. These combined methods ensure both proper concentration and efficacy of the cleaning process in compliance with our food safety program.
Your chemical supplier should also supply titration kits for testing concentration. While conductivity meters and flow can help, they're not as accurate and you should use a titration method to check on a risk assessed basis.
When you're deciding where to check and how often, do consider where you dilute your chemicals. If it's in one place you will need to do fewer checks than if you have multiple dilution stations. Also when taking a sample, allow it to run for a minute or so first so it's representative.
These are the kind of test kits they supply: Chemical Titration Test Kits
Depending on the contractor, in the UK at least, some of the suppliers will do this testing for you (depending on how often they're on site as well). Not sure if that's also the case in the states but worth asking.
Yeah, just ask your supplier, mix accordingly, use whatever test strips or method they recommend. I use strips, which are easy and any auditor is happy with. Test once a week, keep a log, sign off on it.
As stated above, titrations
Your vendor should provide you with an acceptable range too high is $$$$ and maybe difficult to rinse (with detergents) too low and more time spend on mechanical action
sanitizer also has contact time as said concentration, so ensure the equipment is left wet when done (in most but not all instances)
This isnt for manufacturing, its for distribution. None of the chemicals are used on food contact surfaces bc we dont have any. We can use the strips things like glass cleaner and general detergents that require dilution and use the strips according to their pH?
For that application strips will be fine but do be aware as said above, overuse costs you money so titration might be worth it occasionally.
We dose a base (NaOH) at 1% According to the supplier.
I want to start doing titrations.to verify correct dosing.
So to check the procedure.provided by the supplier , I made a 1% solution by weighing 1 g of chemical and then adding 99g of water.
I titrated with HCL 0,1 and then multiplied by the factor supplied by the manufacturer, which SHOULD give 1 , right?
But I got 1.6. can anyone explain the theory behind it, so I understand what I am doing wrong? The 0,1 HCL solution was bought ready made by a lab..
Procedure is: 10ml of solution is titrated with 0.1 HCL with phenolphthalein as an indicator.. titrated to colourless.
Concentration= amount HCL used x factor
Hi AJL,
Easier to see the calculation here Concentration of NaOH in water by titration method – See calculation section at 2:20
Kind regards,
Tony
I realised I was using the wrong factor (for a different chemical) when I did the calculation, I ended up with 1% when I used the correct factor. 🌞
But I get a different value when I used the calculation in the video.
I am guessing it is because the solution is not 100% NaOH, it has a 'bulk density' of 1.3 kg/L.
How can I link the 2 things together? So I can convert between % NaOH and % of suppliers chemical solution? Which I believe consists of only NaOH and water.
Hope the question makes sense.
Hi AJL,
I have come across confusion previously where the instructions from the manufacturer of the detergent calculate the percentage of product (detergent) and not the concentration of NaOH which will be less. Is that the difference that you are seeing?
Kind regards,
Tony
Of course I can use their conversion factor and it works, as I got 1% when I made a standard solution of 1 g detergent to 99g water.
But I would like to be able to defend how I arrived at that conclusion and not just trust blindly, the conversion factor supplied. I would like the theory behind it .
The spec is attached (freely available from the website)
Hi AJL,
I can't see an attachment.
The supplier's calculation will be based on the NaOH concentration and factor up to percentage product so you can ask the manufacturer or check the specification which should tell you the percentage NaOH and use that figure.
Kind regards,
Tony
I have tried to attach again
Hi AJL,
That hasn't worked, just post a link to the product specification on their website, that is just as easy to look at.
Kind regards,
Tony
Hi AJL
As this CIP detergent contains NaOH and KOH and an Acid direct calculations are complicated.
Formulation
Sodium hydroxide 15-25% w/w
Potassium Hydroxide 1-3% w/w
2-Phosphonobutan-1,2,4-tricarboxylic acid 1-3% w/w
Without an exact % of each chemical you cannot calculate exactly the content from titration.
The factors are different because of the density as you would expect
Factor
(w/w %): 0,18 based on Density ~ 1,30 kg/l
(v/v %): 0,14
The best you can do is estimate from the % of each in the product as per the manufacturers titration instructions unless the manufacturer is more specific regarding the % of each which I suspect they will not do 'officially'.
Kind regards,
Tony
It's much appreciated 👍🏻
Thanks ☺
It's much appreciated
Glad to have helped.
Have a good weekend AJL.
Kind regards,
Tony