Why does Anova sous vide tell me to cook salmon to unsafe temperatures

A fair amount of cooks and recipes disagree with the official guidelines when it comes to salmon's desired cooking temperature. The 145F guideline applies to all fish and shellfish, and is meant as a safety standard, not a culinary guideline. I've seen target temperatures for salmon ranging from 120 to 150F (most being in the 120-135F range).

The main reason for the 145F temperature is parasites such as Anisakis, which requires the following to kill:

How can I prevent anisakiasis?

Do not eat raw or undercooked fish or squid.

The FDA recommends the following for seafood preparation or storage to kill parasites.

Cooking (Seafood in General)

• Cook seafood adequately (to an internal temperature of at least 145° F [~63° C]).

Freezing (Fish)

• At -4°F (-20°C) or below for 7 days (total time), or

• At -31°F (-35°C) or below until solid, and storing at -31°F (-35°C) or below for 15 hours, or

• At -31°F (-35°C) or below until solid and storing at -4°F (-20°C) or below for 24 hours.

You should research what other parasites and bacteria may be found in the salmon you source, and what mitigation strategies there are (such as freezing, as seen above). If all of them can be done without heating the fish above 120F, you may have a way to follow those guidelines safely. Otherwise, stick to what the USDA, FDA, and CDC agree on :)

All this misses the reality of how cooking in a circulator (aka Sous Vide method) can be done at lower temperatures.

The commonly accepted temperatures to make food safe bring the food to that temperature for a short period of time.

Sous Vide methods bring the food to a lower temperature but for a much longer period of time.

Both essentially use probability. At that temperature, for that length of time, 99% (or whatever number) of the potentially harmful bacteria will be killed.

This is why you can SV tenderloin to a beautiful Medium Rare, and not exceed the temperature that it finishes at. By cooking at a lower temperature, you gain desired texture.

First, unsafe food won't automatically make you sick. It just means that nobody guarantees it won't make you sick, while for safe food, you have this guarantee. What happens when you eat it is anybody's guess - most of the time you will be fine, some of the time you will get sick.

People do use practices which they informally feel as safe even when they are not officially approved. The sous vide crowd is a bit better than granny's hearsay there, in that they tend to use combinations of time and temperature which can achieve the same reduction of bacterial load as a momentary peak of the FDA-recommended temperature. This is not the same as having been confirmed in the kind of empirical study the FDA does.

So eating safe food or not comes down to your own risk tolerance. There are many food preparation methods which are unsafe, but widely used. You can choose to use them or not, that's a personal preference.

The sole reason why we undercook fish is, because it will be ruined and overcooked when we pasteurize it. Fish is almost always, lightly cooked.

However, freezing is also another method for parasite reduction. When you’re buying fish to be cooked sous-vide, you can ask if and how it was frozen, and refer to the guidelines of freezing fish for parasire reduction.

Even what you see in the butchers case is often frozen.

Truly fresh fish you typically buy in a fish market and cook that day. That fresh it is not likely to have bacteria to kill.

Not a guarantee but often the salmon is flash frozen on the ship. If you thaw in the fridge and cook immediately again it is not like to have any bacteria to kill. Even if they thaw it to cut fillet I suspect they keep it under 40 F.

That said the 145 F is recommenced to kill bacteria. If the fish was in the fridge for 2 days then should go for 145 F.

Protein cook at a low temperatures. If I am not mistaken it start cooking at 45'C but the bacteria will survive the heat until 60'C. So basically you need to overcook your salmon to the safety zone, but it is find to eat it at 45

Given that "treated" salmon can be eaten uncooked, it is essentially not wrong for any recipes to state any temperature, as long as the salmon is "properly treated".

The thing is pathogens (bacteria and parasites) don't instantly die. At least not all of them. Pretty much like human can survive very high temperatures, say 60C, for some seconds or even minutes.

The higher the temperature, the faster the pathogens will die. The FDA standard, which is pretty safe, probably assume heating will stop once 63C is reached. Meaning all pathogens will die within matter of seconds.

It is definitely possible, to heat the meat up to "merely" 60C and keep it there for longer time until all the pathogens are killed. That way, it is essentially just as safe. In general this kind of treatment is called pasteurisation, largely used in the diary industry.

However, it is largely unknown how long the food has to maintain certain temperature until all pathogen dies.

My take on this is that caution should be taken. I personally would not dare to eat sous vide salmon less than 50C.