Hello Everybody!
Salted ripened anchovies as these described by Peter Howgate, and produced in some Mediterranean and South American countries from Engraulis spp, are products with an Aw ~ 0.75 and therefore rather stable regarding common sources of spoilage and deterioration. Some similar products are produced with other pelagic non-Engraulidae fish around the world too.
Vegetable oils (in general olive oil) prevent the possibility of oxidation (one problem not solved with salting) and in general good processors close jars and cans with oil overflowing them.
Oil and careful packaging is important too for other reason, there are some extreme halophylic fungi capable to transform histidine in histamine (even if at a very low rate). Histamine (in particular temperature abuse of the raw material) is the main (natural) possible hazard of this product.
This type of product derivate from the Old Roman "garum" and it is a "relative" of some Asiatic fish liquid sauces like "nuoc man" in Vietnam and similar products in the Philippines and other countries of the region. This means that from the epidemiology side we are in the rather safe side.
It is utilized in many traditional (including historical) and contemporary dishes; from Caesar Salad (easy to see why), pizza (different types), pasta (different types) and in some Mediterranean countries some wonderful dishes like pumpkin ("zucchini") flowers and "Bagna cauda" (do not ask me for the English name of the last one!). Of course salted ripened anchovies are one of the ingredients of many other traditional products, for instance it is an ingredient of the Worcestershire sauce in UK (may be in the formula since the Roman Period!), and this means in all countries with some UK-tradition.
Normal storage at ambient temperature (say around or less 25 °C) or a bit higher temperatures for a short time do not have a noticeable effect on the product; but temperatures above 30 °C start to modify the texture of the product (some proteolytic enzymes are there). At the very end the salted ripened fillet could liquefy. Voila! And we get a cousin of the Asiatic fish sauces. No safety problem, but it is a different product (easy to see why in tropical Asia it is much more convenient to arrive directly to the liquid product).
Marinated anchovies are a quite different product. In this case the stability of the product is reached (or should be reached) by the simultaneous action of low pH, salt (not too much) and temperature. In European marinades the Aw is in the range of 0.96-0.98 and pH is around 4.1. This takes us (barely) out of the reach of bacteria, but spoilage by moulds and yeasts is possible. Some substances present in vinegar (utilized to low the pH in marinated products) have anti-mycotic properties, and there are in some countries some permitted food additives to control this problem.
However, the main problem is with enzymes, cathepsin in fish muscle has its optimal range at about pH 4.5 and therefore and it is difficult to prevent the hydrolysis. At about 25-27 °C the keeping time would be around 3 weeks. At fridge temperature (say 4-6 °C) keeping time could be several months.
Histamine (temperature abuse) continues to be the main hazard with marinated anchovies. Depending on the specie of fish marinated and the geographic area, some parasites could represent a hazard too, particularly because they could survive some time after processing at that pH and salt concentration (Aw). Since at ambient temperature keeping time is short, this means that the product may be consumed before the parasite could be eliminated. This type of hazard is very unlikely in the case of salted-ripened anchovy, because ripening (before to produce the final anchovy fillet) takes several months (depending on the external temperature) and any type of possible parasite has surely been eliminated by then.
Marinated anchovies are utilized as "anti-pasto" this means as appetizer, or as a part of "sea salad" with other type of marinated fish. Obviously salted-ripened anchovies could be utilized as "anti-pasto" too, but they are utilized in many more dishes and preparations than marinated anchovies.
Finally, in a number of countries some anchovy species are packed and canned and retorted as sardine-like products. I do not want to open here a discussion on the specie-substitution subject, because, in the other hand, sardines are utilized to counterfeit salted-ripened anchovy. Just to say that this type of product also exists.
I hope this will help to clarify a bit more this subject.
Hector M. Lupin
Please notice: Aw, pH values and keeping times here mentioned are these I have measured like 3 decades ago, and they did not cover all type of possible products and range of temperature. I do not say they are the standard and/ or regulatory EU values for this type of products.
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>From : owner-seafood@ucdavis.edu
To : seafood@ucdavis.edu
Cc :
Date : Fri, 20 Jul 2007 11:29:09 +0100
Subject : Re: 'canned' Anchovy - shelf stable or must refrigerate?
> Christian does not tell us where 'here' is - see Pam's recent message about
> not being able to deduce the country of origin from the e-mail address - but
> I see from an Internet search that it seems to be Canada. I live in Britain
> and I have in front of me a can of 'Anchovy fillets in olive oil', net wt.
> 50g, drained wt. 35g product of Morocco. They are made in other
> Mediterranean countries other than Morocco - I have seen the process
> underway in Spain - and in South America. The product is very salty, but I
> like them despite the current nutrition police campaign to reduce salt in
> the diet, and is the product presumably of 14% salt concentration already
> mentioned in this thread and defined in the Multilingual Dictionary of Fish
> and Fish Products as: 'headless gutted or whole ungutted anchovies packed in
> salt in barrels and allowed to ripen for about four months at temperatures
> up to 30degCuntil the flesh has reddened right through: as semipreserves,
> sold whole, filleted in oil or sauce, flat or rolled with or without capers;
> packed in cans, glass jars etc. ... '. If what you are selling in Canada is
> this product then it is shelf stable and need not be held under
> refrigeration. I see the 'best before end' date on the can I have is Nov
> 2008, and the product is sold on the open shelves in shops here in Britain.
> In all the many years I have been buying this product I have never seen it
> offered other than on open shelves. Delicatessen shops and delicatessen
> counters in supermarkets sell a marinated anchovy fillet product which seems
> to come from Italy judging from the type of shop that sells it. Judging from
> the taste it is only lightly salted and I assume it is predominately the
> vinegar that exerts some preservative action. It is intended as an antipasto
> ingredient. Because this product is sold loose - at least at retail level -
> and not prepackaged I have not seen a shelflife date or advice on storage
> for it. I don't expect it to have a long shelf life and I hold it in the
> refrigerator at home, but we have usually scoffed within a day or two
> anyway. These marinated fillets are available in jars or plastics containers
> from mail order companies and would then be labelled with a shelflife date,
> but I have never bought any this way so can not tell you what it is. May
> Italian recipes ask for preserved anchovies, e.g. spaghetti alla putanesca,
> but it is never clear if they mean the hard salted, ripened product, or the
> marinaded one, though I tend towards the former. Can any Italian reader
> clarify for me?
>
> Best wishes
>
> Peter Howgate
>
> ----- Original Message -----
> From: "Christian Vogl" <cvogl@shafer-haggart.com>
> To: <seafood@ucdavis.edu>
> Sent: Tuesday, July 17, 2007 10:11 PM
> Subject: 'canned' Anchovy - shelf stable or must refrigerate?
>
>
> We have a customer in Australia who tells us that anchovy in cans
> (packed in oil) are sold 'shelf stable' there.
> Here, we refrigerate them.
> It was always my understand that this was required because of the lack
> of thermal processing. But if this is the case, how can Australian
> stores market them on the shelves instead of the cooler?
> Any thoughts appreciated!
> Best regards,
> Christian
>
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