Allowable Nitrite/Nitrate levels in the UK

[Parson Snows]

The following information is from the UK Government

*** Original Text follows

The use of miscellaneous additives in foodstuffs in the UK is governed by
the 'Miscellaneous Food Additives Regulations 1995' (Statutory Instrument
(SI) number 3187, as amended). This implements European Parliament and
Council Directive 95/2/EC, and applies in all Member States within the EU.

Under Schedule 2 Part C of the above Regulations, Potassium Nitrite (E249)
and Sodium Nitrite (E250) are permitted in the following foods at the
following maximum indicative and residual amounts: non-heat treated, cured,
dried meat products at a maximum level of 150mg/kg (indicative) and 50mg/kg
(residual), other cured meat products canned meat products Foie gras, foie
gras entier, blocs de foie gras at a maximum level of 150mg/kg (indicative)
and 100mg/kg (residual) and cured bacon at a maximum level of 175mg/kg
(residual).

Sodium Nitrate (E251) and Potassium Nitrate (E252) is permitted in the
following foods at the following maximum indicative and residual amounts:
cured meat products, canned meat products at a maximum level of 300mg/kg
(indicative) and 250mg/kg (residual).

As you may wish to consult the regulations yourself I have provided a link
to the website. The link is:-
http://www.hmso.gov.uk/stat.htm
In each case you will need to click on 'continue' at the bottom of the page
to progress to the Schedules in all of the above Regulations.

Please contact me if you require any further information.

Regards
Andy Furmage
Novel Foods, Additives and Supplements Division

*** Original Text Ends

Schedule 2
http://www.hmso.gov.uk/si/si1995/Uksi_19953187_en_4.htm

hope that this is of some use to you

kind regards

Parson Snows

[Oddley]

What a coincidence I emailed andy about a week ago asking for the same Info. He's going to get fed up with us.

Can anyone explain in this context the meaning of indicative and residual as below.

Under Schedule 2 Part C of the above Regulations, Potassium Nitrite (E249)
and Sodium Nitrite (E250) are permitted in the following foods at the
following maximum indicative and residual amounts: non-heat treated, cured,
dried meat products at a maximum level of 150mg/kg (indicative) and 50mg/kg
(residual), other cured meat products canned meat products Foie gras, foie
gras entier, blocs de foie gras at a maximum level of 150mg/kg (indicative)
and 100mg/kg (residual) and cured bacon at a maximum level of 175mg/kg
(residual).

I take it that milligrams per kilogramme's also means parts per million.

1000mg = 1gm
1000gm = 1kg
.: 1000 * 1000 = 1000000

This might help someone and also gets it clear in my own head. If I am wrong please say.

[Parson Snows]

Oddley

Yes mg per Kg is the same as ppm (1/1 000/1 000 or 1/1 000 000)

Indicative refers to the amount of ingoing restricted ingredient

Residual refers to the amount of remaining restricted ingredient
(after all processes)


hope that clears that up

kind regards

Parson Snows

[Oddley]

Parson thanks for the info.

We are still in the same boat as before we have no means of working out scientifically the ingoing amounts or the residual amount especially for dry cured meats or the relationship between ingoing and residual amounts.

[Oddley]

There is so much I don't understand about these regulations perhaps someone more knowlegeable than me can explain.

Under Schedule 2 Part C of the above Regulations, Potassium Nitrite (E249)
and Sodium Nitrite (E250) are permitted in the following foods at the
following maximum indicative and residual amounts: non-heat treated, cured,
dried meat products at a maximum level of 150mg/kg (indicative) and 50mg/kg
(residual), other cured meat products canned meat products Foie gras, foie
gras entier, blocs de foie gras at a maximum level of 150mg/kg (indicative)
and 100mg/kg (residual) and cured bacon at a maximum level of 175mg/kg
(residual).

OK with Potassium Nitrite (E249) and Sodium Nitrite (E250)
You can have a residual amount or the amount left in the meat after curing of

50mg for dry cured meats
175mg for bacon (this seems a lot)

Sodium Nitrate (E251) and Potassium Nitrate (E252) is permitted in the
following foods at the following maximum indicative and residual amounts:
cured meat products, canned meat products at a maximum level of 300mg/kg
(indicative) and 250mg/kg (residual).

With Sodium Nitrate (E251) and Potassium Nitrate (E252)
You can have a residual amount or the amount left in the meat after curing of

250 mg for dry cured meats

What I don't understand is

1: If you rub in 50 mg of sodium nitrite into 1 kg of meat the meat will absorb it all therefore the indicative and residual amounts are 50 mg so I really don't understand what they mean by indicative and how it relates to residual.

2: If you are allowed to rub into a piece of meat 250 gm of potassium nitrate as we all know some will be converted to potassium nitrite how much? Will more than 50 gm of nitrite per kilo of meat be converted.

3 If you use sodium nitrate and sodium nitrite do you use as a rub 250 gm sodium nitrate and 50 gm sodium nitrite per kilo of meat.

4: I recently did a salt beef using prague powder #1 and worked out the sodium nitrite level at about 78 ppm would this be considered as bacon 175ppm nitrite or dry cured meat 50 ppm?

It is very important to understand this stuff and I feel really stupid because I don't

[Parson Snows]

Oddley

I haven't forgotten that I said I would post information on nitrates/nitrites. I am working on it when I have the time and will post it when finished. It is intended that it be reviewed first (moderators etc) to try and avoid lots of questions being posted afterwards. I am trying to make it as clear and concise as possible. Please bear with me. As to your salt beef you wrote

I recently did a salt beef using prague powder #1 and worked out the sodium nitrite level at about 78 ppm would this be considered as bacon 175ppm nitrite or dry cured meat 50 ppm?

If you look at the standard it states

other cured meat products canned meat products Foie gras, foie
gras entier, blocs de foie gras at a maximum level of 150mg/kg (indicative)
and 100mg/kg (residual)

This is where your salt beef falls under

hope that this clears at least this up.

kind regards

Parson Snows

[Oddley]

I'll tell you what Parson you post the formulas and I'll write a program to contain, use and display the results and make it available to forum members.

[Parson Snows]

Sorry Oddley for this part of the curing process - the conversion of nitrates into nitrites - there are really no formulas. This is a part of what I presently writing ...

If nitrate is used as the curing agent, it must first be converted (reduced) to nitrite by microorganisms such as Micrococcus spp. present on the meat or poultry. However, the amount of nitrate that is reduced to nitrite is dependent upon the amount of these nitrate-reducing bacteria present along with several other environmental conditions, such as

� Temperature
� Moisture content
� Salt content and
� pH

With the number of variables involved it is easy to see that the conversion rate and subsequent amount of nitrite that is formed is at best difficult to predict and/or control. Similarly, the further reduction of nitrite to nitric oxide, which reacts with myoglobin (muscle pigment) to produce the typical �cured pink colour�, is also affected by the same conditions. On occasion � due to the variables previously mentioned � excessive nitrate reduction will take place, resulting in an overly high concentration of nitrate build up. In the presence of lactic acid this excessive nitrite results in severe oxidation of the meat pigment (myoglobin), producing a green pigment (oxymyoglobin). This is commonly referred to as �Nitrite Burn�. However, if nitrite is used then there is no need for the nitrate reduction process and the development of the cured colour is achieved much quicker. It is due to these wide nitrate variations and the demand for more accurate and faster curing methods that has lead to the greater use of nitrites or a combination of nitrates and nitrites as opposed to simply using nitrates for meat and or poultry curing. It has been found that as the curing proceeds, the salt concentration in the cure falls whilst the nitrite concentration rises.

kind regards

Parson Snows

[Oddley]

What I am about to say in no way denigrates your knowledge.

What we all really need is some guidelines to work within. as an example if you had a dry cure using only nitrates it is unlikely that all of it would be converted to nitrites on the other hand it is just as unlikely that none of it would be converted to nitrites.

Example:

Nitrates converted to Nitrites = 100% = Wrong
Nitrates converted to Nitrites = 0% = Wrong

There must somewhere be some research which gives a likely range of figures.

Example:

Nitrates converted to Nitrites = 25-80% = Right

At least with figures such as these we could err on the side of caution.

I have spent a lot of time researching this and have read all the info in your last post in different places scattered all over the net. It will be great to have all the info you are going to post all in one place.

At the end of the day I can use stored knowledge and common sense with a bit of math to get by.

[Parson Snows]

Oddley

No offense taken to anything, by all means question any of my inputs/postings etc. that is one of the reasons that I would like topics such as this reviewed by the moderators etc, prior to posting. The actual language of some of research papers is very technical/scientific. I will however include several of these pages in the final posting. I'm just trying to put it more in layman's terms.

Yes it is likely that not all nitrate would be converted/reduced to nitrite though it is highly unlikely nearly impossible that none of it would be converted. Though I can guarantee that the people who set the standards - regardless of which country - have taken all of this into account.

As to erring on the side of caution DON'T. Just use the maximum amount of ingoing/indicative restricted ingredients stated in the standards. Undercuring is just as bad as overcuring.

kind regards

Parson Snows

[Oddley]

Hi Parson I have just been thinking as unusual as that might sound...

I think I now understand the relationship between Indicative and residual amounts of nitrates/ nitrites and it can be expressed thus.

Indicative = 100% of Ingoing chemical

Residual = Indicative - Changes in Chemical

A simple equation but one has to know that changes take effect even in the nitrites added to the product.

[Parson Snows]

Oddley

In the broadest sense YES.

For your information

Ingoing ingredient: the amount of an ingredient added to a product at the time of formulation

Residual amount: the amount of remaining restricted ingredient after all formulation processes are completed.

kind regards

Parson Snows

[Oddley]

Ingoing ingredient: the amount of an ingredient added to a product at the time of formulation

Then Indicative makes no sense at all. In the HMSO doc it gives definitive indicative amounts if that amount is not all absorbed then you would need a new term to describe the absorbed amount.

They would also be restricting the amount of chemical used to obtain the optimal residual amount.

[Parson Snows]

Oddley

I mentioned that I wasn�t ready to post anything so as I sat up Christmas Eve writing this - this is your Christmas present from me. I�ve tried to present it according to the direction that it seems you were heading in.

Nitrites dissipate very quickly therefore it is for items that require or will be subjected to a long curing period that require BOTH nitrates and nitrites, and not those with a short curing period. The nitrates acting during the curing period like a �time released� supply of nitrites.

Saltpetre (UK)
also spelled Saltpeter, also called Nitre, or Niter, any of three naturally occurring nitrates, distinguished as

(1) ordinary saltpetre, or potassium nitrate, KNO3;
(2) Chile saltpetre, cubic nitre, or sodium nitrate, NaNO3; and
(3) lime saltpetre, wall saltpetre, or calcium nitrate, Ca(NO3)2.

These three nitrates generally occur as efflorescence�s caused by the oxidation of nitrogenous matter in the presence of the alkalis and alkaline.

A simple relationship between Indicative and residual amounts of nitrates/nitrites can be expressed thus.

For the nitrate example.

If nitrate is used as the curing agent, it must first be converted (reduced) to nitrite by micro-organisms (bacteria) such as Micrococcus spp. present on the meat or poultry. However, the amount of nitrate that is reduced to nitrite is dependent upon the amount of these nitrate-reducing bacteria present along with several other environmental conditions, such as

� Temperature
� Moisture content
� Salt content and
� pH

With the number of variables involved it is easy to see that the conversion rate and subsequent amount of nitrite that is formed is at best difficult to predict and/or control.

Indicative = 100 % of the amount of an Ingoing restricted ingredient (RI) added to a product at the time of formulation

As previously mentioned NOT ALL of the Ingoing restricted ingredient (RI) will remain in the product once all formulation processes are completed. This is due to the initial heat process (if applicable), chemical additives such as polyphosphates, the pH of the product and product storage temperature, and duration.

Residual amount (US): the amount of remaining restricted ingredient after all formulation processes are completed, expressed as NaNO2 (Sodium Nitrite).

Or

Residual amount (UK) : the amount of remaining restricted ingredient at point of sale to the final consumer, expressed as NaNO2 (Sodium Nitrite).

Therefore

Indicative nitrate = (converted nitrate + unconverted nitrate)

Residual nitrite = (converted nitrate - amount of nitrite lost due to decomposition) see Note 1

However, as converted or reduced nitrate = nitrite this can also be expressed

Residual nitrite = (ingoing nitrite - amount of nitrite lost due to decomposition) see Note 1

Note 1: this amount is in a state of flux, reducing constantly over time, in theory down to 0.



The presence of nitrite is much easier to measure than the presence of nitrate.

Hopefully this makes a little bit more sense to you.

Kind regards

Parson Snows

PS don�t worry about it over Christmas. All the best to everyone for 2005. This is my last post of 2004, I�ll catch up with everything when I log back on in 2548.

[Oddley]

I'm in the middle of making dinner so have to be quick thanks Parson.

All I have to give you is My very best wishes and a Merry Christmas