Brining Salmon

[Sam Shepherd]

Hi guys,
I have an environmental health officer asking for the per kilo ratio of salt to salmon! I'm slightly concerned telling him a visibly healthy coating thicker on the thick end and thinner on the thin end wont go down to well. does anyone know any ideas if anyone is running a salt per kilo ratio or what a good one would be!?
Thanks in advance!
Sam.

 

[atomicsmoke]

Grab a fish, get its weight, salt it your way (thick for thick and thin for thin) then check the weight again. Substract the unsalted fish weight and calculate the ratio.

 

[daveomak]

Sam, afternoon.... If you have an environmental health officer asking for the per kilo ratio of salt to salmon, you must be a licensed processor/retailer.... Should have gone to school, and should know that...
Because you are in the UK, ask Wade.... He's the resident "expert" in the UK, on this forum....

 

[wade]

Hi Sam. Is it for traditional smoked salmon or for hot smoked salmon? For commercial traditional smoked salmon production there is no set requirement for a specific salt to salmon ratio as each smokery has their own production recipe. I expect that your EHO is just wanting to understand your production and to ensure that you have a standardised production method. Almost certainly they will also have asked you what your product shelf life was and they will expect you to have this confirmed through lab testing - many of us use ALS Laboratories for this.
If they are asking for a ratio then give it to them - just weigh the fish before adding salt and then after. Do this several times and take an average.

I produce mainly traditional smoked salmon and my salmon curing process involves coating the salmon in salt cure and then shaking it off - what sticks to the fish is sufficient. My EHO is happy with this and it provides a fairly consistent ratio of salt to fish. The initial salt is applied primarily to inhibit the growth of surface bacteria at the beginning of the curing process and to start the removal of available water. This keeps it sufficiently safe during the next stage of production which is the dehydration in the smoker and the application of smoke.

Happy to discuss further here or offline if you need more information on the Lab testing.

 

[wade]

Sam, afternoon.... If you have an environmental health officer asking for the per kilo ratio of salt to salmon, you must be a licensed processor/retailer.... Should have gone to school, and should know that...

That was a particularly unhelpful and judgemental comment Dave. We are here to encourage and support people with their smoking/curing questions.

Each local EHO will have their own questions and so it is not surprising that unexpected questions are sometimes asked. My EHO has never asked me to provide a specific salt ratio and if you look at other commercial producers (Foreman and Fields is a good example) they do exactly what Sam is currently doing - adding enough salt until the amount "looks about right".

 

[CharlotteLovesFood]

Wow, I wouldn't have a clue either and I did go to school ;)
This post did prompt me to do a Google search out of sheer curiosity and this article popped up...not sure if it's any help?
https://www.recipetineats.com/cured-salmon-gravlax/

I'm new here too, but Wade is your guy...everybody knows he looks out for us newbies and has a vast range of experience and knowledge, but most importantly humble.

 

[Sam Shepherd]

Hi guys,
Thank you very much for all the kind responses I have had. Although I believe others need to remember we only know what we are taught and no-one should ever feel ashamed that they haven't been taught but only be ashamed they haven't learnt when taught! But hey ho! I find a per kilo ratio very strange and don't know of any other smokehouse to use it. But as it happens we are on the outskirts of a city and follow a different EHO We feel happy with how we brine and have even had our salmon tested twice before once voluntary and once on a surprise visit. So I will be following the great advice of weighing the salmon before and after added salt and take an average!
Thank you everyone!

 

[atomicsmoke]

Hi guys,
Thank you very much for all the kind responses I have had. Although I believe others need to remember we only know what we are taught and no-one should ever feel ashamed that they haven't been taught but only be ashamed they haven't learnt when taught! But hey ho! I find a per kilo ratio very strange and don't know of any other smokehouse to use it. But as it happens we are on the outskirts of a city and follow a different EHO We feel happy with how we brine and have even had our salmon tested twice before once voluntary and once on a surprise visit. So I will be following the great advice of weighing the salmon before and after added salt and take an average!
Thank you everyone!

If i were you i would document that ratio and incorporate it in my process. Inspectors/auditors love documented processes.
And you never know when you have to delegate the fish salting. "Seems about right" is harder to explain than 150g salt/kg fish.

 

[atomicsmoke]

Since you have your product tested-what water phase salt level are you aiming for?

 

[wade]

The shelf life testing is usually only microbiological and with Salmon it will depend on your process as to the length of time that you are permitted to state. It can vary from as low as 10 days to as long as 28 days. Mostly we go for a water loss weight reduction of ~18%

 

[atomicsmoke]

The shelf life testing is usually only microbiological and with Salmon it will depend on your process as to the length of time that you are permitted to state. It can vary from as low as 10 days to as long as 28 days. Mostly we go for a water loss weight reduction of ~18%

Will 18% be reached by the time the smoking stage is completed? Or does it require further drying?

 

[daveomak]

Wade.... In the USA, we set standards that the processor knows.... I was reluctant to mention our standards, as you have verified, your government does not let the processor know what standards to shoot for...
As far as me being not helpful, how about your government being helpful.. If you don't know "what the standards are" how can I be helpful ???
You said, " For commercial traditional smoked salmon production there is no set requirement for a specific salt to salmon ratio as each smokery has their own production recipe."
Am I to understand your government sets no health standards when salting/smoking fish ??? Sounds as if that is so or you are not familiar with the guidelines...

Saber Co. of Anacortes, WA, is recalling more than 1,200 units of their “Gerard & Dominique Seafoods” brand Cold Smoked Wild Coho Salmon Lox from the marketplace, urging consumers to not eat the products because of concerns of botulism poisoning.
The recall was initiated because the product’s water phase salt tested below 3.5 percent, according to the recall notice posted on the FDA’s website.
“Labeling instructions state to freeze or refrigerate, once thawed they can be kept unopened in the fridge for up to 30 days,” the recall says. “(However) because the water phase salt is under 3.5 percent, the product must remain frozen until ready to consume.”

Here you go.....
Chapter 7: Smoked Fish and Fishery Products
http://seafood.oregonstate.edu/.pdf Links/Compendium/Chapter-7-Smoked-Fish.pdf

 

[daveomak]

Brining or dry-salting
A.
Brining must be carried out so that the temperature of the brine does not exceed 60ºF
(15.5ºC) at the start of brining. If the brining time exceeds 4 h, the brining must take
place in a refrigerated area at
38ºF 3.3ºC) or lower.
B.
For dry salting, the fish must be returned to a refrigerated area of 38ºF (3.3ºC) or lower
immediately after the application of the salt.
C.
Different species of fish must not be mixed in the same brining tank.
D.
Brines may not be reused unless there is an adequate process available to return the brine
to an acceptable microbiological level.
E.
Fish must be rinsed with freshwater after brining.
Heating, cooking, or smoking operations
A.
Fish must be arranged without overcrowding or touching each
other within the
smokehouse oven or chamber to allow for uniform smoke absorption, heat exposure, and
dehydration. Fish smoked in the same batch should be of relatively uniform size and
weight.
B.
Liquid smoke, generated smoke, or a combination of liquid smoke and generated smoke
must be applied to all surfaces of the product. Liquid smoke can be applied to the product
before, at the beginning, or during the process. Generated smoke is applied to the fish
during the first half of the process. If a combination
of liquid smoke and generated smoke
is used, the procedures for liquid smoke must be followed and the generated smoke can
be applied at any stage of the process.
Hot process smoked fish
A.
Hot process smoked fish shall be produced by a controlled process that
utilizes a
monitoring system such as calibrated probes or recording thermometers to ensure that all
products reach the required temperature. The temperature readings shall be obtained by
inserting an accurate temperature indicating device into the thickes
t flesh portion of three
or more of the largest fish in the smokehouse compartment. The coldest reading thus
obtained shall be recorded in a fish smoking record as being the internal temperature of
fish being smoked. The internal temperature of fish being
smoked shall be obtained and
recorded with the time taken at least three times during the operation of heating each load
or batch of fish to assure that the required heat treatment has been accomplished. Each
batch of smoked fish shall be identified as to
the specific oven load, product temperature
obtained, and data processed.
B.
For hot process smoked fish to be air packaged, a controlled process must be used to heat
fish to a continuous temperature of a least 145ºF (62.8ºC) throughout each fish for a
minimu
m of 30 min for fish brined to contain not less than 2.5% water phase salt in the
loin muscle of the finished product.
C.
For hot process smoked fish to be vacuum or modified atmosphere packaged, a controlled
process must be used to heat fish to a continuous
temperature of at least 145ºF (62.8ºC)
throughout each fish for a minimum of 30 min for fish brined to contain not less than
3.5% water phase salt in the loin muscle of the finished product or the combination of
3.0% water phase salt in the loin muscle of
the finished product and not less than 100
ppm nor more than 200 ppm sodium nitrite.

Cold process smoked fish
A.
Cold process smoked fish shall be produced by a controlled process that utilizes a
temperature monitoring system positioned within the smoking chamber to assure that all
products do not exceed process temperatures in accordance with one of the following
methods:
1.
The temperature in the smoking chamber does not exceed 90ºF (32.2ºC) during a
drying and smoking period that does not exceed 20 h; or
2.
The t
emperature in the smoking chamber does not exceed 50ºF (10.0ºC) during a
drying and smoking period that does not exceed 24 h; or
3.
The temperature in the smoking chamber does not exceed 120ºF (48.9ºC) during a
drying and smoking period that does not exceed 6
h for cold process smoked
sablefish.
B.
For cold process smoked fish to be air packaged, only fish that have been brined to
contain not less than 2.5% water phase salt in the loin muscle of the finished product may
be used.
C.
For cold process smoked fish to be
vacuum or modified atmosphere packaged, only fish
that have been brined to contain not less than 3.5% water phase salt in the loin muscle of
the finished product or a combination of 3.0% water phase salt in the loin muscle of the
finished product and not
less than 100 ppm nor more than 200 ppm sodium nitrite may be
used.

NMFS Guidelines
Top
Inspection and certification of vacuum packaged hot-processed smoked or hot-processed smoke-flavored salmon
A.The processing facility must be in compliance with the requirements of 50 CFR Part 260.
B.Defrosting of eviscerated frozen fish shall be carried out in:
1.Air at 45F (7.2C) or below until completely thawed and the internal
temperature of any part of the fish does not exceed 45F (7.2C).
2.A continuous water flow tank or spray system
until thawed. Salmon shall not be
mixed with other species during thawing. Fish shall not remain in the tank for
over 4 h after they are completely defrosted and the temperature in any part of the
fish shall not exceed 60F (15.6C) during this period. If longer delays and
encountered, the fish shall be returned to temperatures of 38F (3.3C) or below until brined.
C. Both fresh and thawed fish shall be washed thoroughly with a vigorous chlorinated water
spray or in a continuous water flow system prior to
brining. (Chlorine concentration in water shall not exceed 50 ppm available chlorine).
D. All fish shall be dry-salted at a temperature not to exceed 38F (3.3C) throughout the
fish, or if brined, the salmon shall not be mixed with other species of fish in the same
tank and shall be brined in such a manner that the temperature of the fish and brine:
1. Does not exceed 60F (15.6C) at the start of the brining, and
2. If the brine time exceeds 4 h, the brining shall take place in a refrigerated room of
42F (5.6C) or lower. The product may not be held above 38F (3.3C) for
more than 48 h.
3. Brines may not be reused unless there is an adequate process (e.g., ultrafiltration)
to return the brine to an acceptable microbiological level.
[Note: Brine tanks that have been used to brine other species of fish shall be cleaned and
sanitized before being used to brine salmon]
E. Hot-process smoked or hot-process smoke-flavored salmon shall be brined in such a
manner that the final sodium nitrite content
of the loin muscle of the finished product shall be no less than 100 ppm and no more than 200 ppm (parts per million) after processing. These same products shall contain not less than the minimum concentrations
of one of the following combinations of water phase salt (w.p. NaCl) and sodium nitrite
in the deepest part of the loin:
% w.p.
NaCl.. ppm sodium nitrite
3.5....100
3.4....120
3.3....140
3.2....160
3.1....180

F. Hot-process smoked or hot-process smoke-flavored salmon shall be heated by a
controlled heat process that provides a monitoring system (e.g., calibrated probes or dial
thermometers) positioned in as many strategic locations in the oven as necessary to
assure that all products reach the minimum internal temperature.
[Note: The temperature monitoring device shall be tested for accuracy against a known
standard thermometer upon installation and at least once a year thereafter, or more
frequently if necessary, to ensure their accuracy. Graduations on the temperature
monitoring device shall not exceed 2F (1.1C) within a range of 10F (5.6C) of the
processing temperature.]
Each fish or fish portion shall be heated to an internal temperature of 150F (65.6C) or
higher and maintained at 150F (65.6C) for 30 min or longer.
G. Liquid smoke or generated smoke or a combination of liquid smoke and generated smoke
shall be applied to the entire product. If only liquid smoke is used in the process it can be
applied to the product prior to, at the beginning of, or during the process. Liquid smoke
added during the process shall be applied before the internal temperature of the product
exceeds 125F (51.7C). The liquid smoke shall be prepared by the aqueous process
(e.g., U.S. Patent 3,106,473) and have a minimum of the following major constituents in
its compositions: 1) 10% titratable acidity; 2) 9 mg phenol/g; 3) 12 g carbonyls/100 ml,
and be used at concentrations of 50% or greater.
When only generated smoke is used in the process, dense smoke shall be applied to the
fish for at least 90 min at the beginning of the process. If a drying cycle is used in the
smoking process, the air temperature surrounding the product shall not exceed 110F(43.3C)
and the time period shall not exceed 60 min at temperatures between 60F(15.6C)
and 110F (43.3C) before the application of smoke. If lower temperatures
(60F [15.6C] or below) are used, this time period shall not exceed 6 h. Generated
smoke shall be produced from burning hardwood. If a combination of liquid smoke and
generated smoke are used, the procedures for liquid smoke shall be followed and the
generated smoke can be applied at any stage of the process.
H. The finished product shall be cooled to a temperature of 50F (10C) or below within 5
h after cooking and further cooled to a temperature of 38F (3.3C) or below within 12 h
after cooking. The finished product shall be maintained at 38F (3.3C) or lower during
all subsequent storage and distribution.
I. Primary packages and master cartons shall be clearly marked with a statement to
maintain the product below 38F (3.3C). If fish are frozen, they shall be clearly labeled
to thaw at refrigerated temperatures and that the thawed product must subsequently be
stored below 38F (3.3C).
J. The finished product shall be analyzed chemically with sufficient frequency to assure that
the required water-phase salt and sodium nitrite is obtained and that other chemical
additives are present at authorized levels. To reduce the possibility of post processing
contamination with food poisoning bacteria, the product shall be vacuum-packaged only
within the facility in which it was processed.
K. Permanently legible code marks shall be placed on the outer layer of every finished
product package and master carton. Such marks shall identify at least the plant where
packed and the date of packing. Records shall be maintained at the processing facility for
a minimum of 6 months from the date of processing as to provide positive identification
(1) of the process procedures (including process/product time, temperature, sodium nitrite
and water-phase salt levels) used for the manufacture of hot-process smoked and hot-process
smoke-flavored fish and (2) of the distribution of the finished product (NMFS,
1984)

 

[wade]

Dave. Thank you for the information - most of which is unfortunately not actually relevant to the discussion we were having about the salt to fish ratio used for the initial dry salting phase of traditional smoked salmon. There is a big difference between individual curing process recipes and final food safety. I think you are getting these confused. Providing you can prove to the satisfaction of the EHO that your specific process results in a product that is safe to eat within the shelf life that you are declaring then that is what they require. The final ratios of salt to meat in the end product will be determined by end product analysis - which is not what we were discussing.

I am not going to discuss further the botulinum issues that you raise in traditional smoked salmon as we are all aware of your paranoia in this area. The short shelf life of the product along with the other preservation steps taken after the initial salting process are there to manage the botulinum risks in traditional smoked salmon.

 

[wade]

Will 18% be reached by the time the smoking stage is completed? Or does it require further drying?

Hi Atomic.

The simple answer to that is a qualified "yes". This is part of your individual product production methodology and each smokery will do things slightly differently to give their own specific smoked salmon variation. The process of water reduction starts before the smoking process.

• If you previously freeze your salmon sides before curing then it will already have lost ~3% of its water upon thawing.
• The amount of salt used in the initial dry salting phase and the length of time it is left before rinsing will affect the amount of water that comes out.
• The temperature and air flow through the smoker and the length of time the fish is left to smoke will also affect the rate and amount of water loss.
• Any subsequent refrigeration before slicing and packing will result in water loss too.

It is all about balancing these in your particular production process so that at the end the water loss is ~18% by weight.