Cookaholics Bulletin Board

I'm sorting out cooking times and temperatures, primarily for sous vide cooking. And I know I'm going to get some questions about safety from people I serve, some of which have at least a passing acquaintance with food safety. The USDA food safety and inspection service says the minimum temperature to hold food at is 140F. That is well above some specified temperatures for sous vide preparation.

Douglas Baldwin's temperature/time table for pasteurization of Meat (Beef, Pork, and Lamb) starts at 131F. But some guides for meat, particularly beef, show rare as 120F - 125F, medium rare as 130F - 135F, and medium as 140F - 145F. So comparing the standards, the food is not safe until it hits 140F. I understand that steak is less likely to have bacteria than ground beef. But I cook both, and right now, am on a ground beef jag. I cannot demonstrate that rare or even medium rare ground beef is "safe" if cooked/held at recommended temperatures for taste versus safety. And to be honest, I'm not planning on serving anything in the rare or medium rare area. I will look at serving somewhere in the medium to medium well.

But that 10 degree difference or so between FDA's 140F and Baldwin's 131F perplexes me and one I want to find some sort of scientific explanation for. If I had a US food inspector walk in and see I was serving burgers at 131F to 135F, would I likely get whacked? If the budding culinary student in the house wants to point to his text book and ask why I am serving food at an unsafe temperature, how can I explain that Baldwin is more correct (given the required time at temperature he specifies) and the USDA's 140F minimum doesn't apply?

Any clarification here will be deeply appreciated.

I've posted this over at eGullet in a thread contributed to by Baldwin occasionally. Maybe some insight will bubble up either here or there at some point.

The USDA is frequently criticized for being conservative in food temperature recommendations, but they are not charged with making food tasty-just safe.

Chefs are primarily concerned with extracting the best flavor from of a dish and recognize that it cannot always happen within the temperature guidelines set by the USDA, but making restaurant diners ill is not going to be a career advancing move.

The divide between flavor and safety is not likely to disappear soon, so it is up to individuals to decide how far one can stray from the absolute safety of USDA recommendations and still maintain an acceptable margin of safety.

The USDA also tends to simplify the rules. After all, if there are too many exceptions and maybes, no one will remember all of it. An intact steak is inherently safer than a wad of beef that's been ground by the ton with a hundred other steer carcasses because the inside of the steak is clean and the outside is going to be seared at temperatures far exceeding 140 degrees. Whereas the ground stuff has no outside and it is all mixed up. The USDA knows that "Get your meat up to 140 degrees." is easier to remember than, "Meat that has possibly been contaminated like factory-ground beef needs to get to 140 degrees. If you grind it at home and use it quickly any bacteria on the outside of the beef that has contaminated the inside likely won't have a chance to grow so you should be okay with cooking it to a lower temperature." Their job is to keep the public safe, not give them a bad case of TLDR.

I respect the intent of the USDA. They're just watching out for the public.
The safest way is to prepare the dish per order and not store them at 130 F.
Unfortunately you'd take a hit because the delivery time is now much longer unless you can come up with a rapid heating technique that doesn't sacrifice quality. (Of coarse it's no longer sous vide) It may be more labor-some as well.

The concept of EXCEPTIONS was mentioned, and this is a long shot, but if you could show high degree of sanitation and non-contamination in your warm storage (sterilize, then warm) with biological test results, would they back off?

This is a tough problem.

Thanks for the insight everyone. I also have a couple of answers over at eGullet. I think using store bought ground beef (particularly here in the Philippines) going anywhere below 140F is just way too risky, regardless of flavor rewards. The only way I'd consider that is grinding my own, so I could control temperature, exposure, and so forth.

Walking anywhere near the meat section of the higher end SM supermarket where I live makes the problem of potential contamination and deterioration very obvious to the olfactory. It is frustrating but one brother-in-law is passing his resume to a meat processing company this week. I'm keeping my fingers crossed I'll have better access to acceptable meat at some point in the future.

Later Update: Douglas Baldwin pointed out the following in answering my hamburger question -

...in a 130°F (54.4°C) water bath (the lowest temperature I recommend for cooking sous vide) it’ll take you about 2½ hours to reduce E. coli to a safe level in a 1 inch (25 mm) thick hamburger patty and holding a hamburger patty at 130°F (54.4°C) for 2½ hours is inconceivable with traditional cooking methods – which is why the “danger zone” conceived for traditional cooking methods doesn’t start at 130°F (54.4°C).

Whew!
I'm glad you're backing-off on this idea. Although sous vide cooking has been around for 40 years thereabouts, it presumes the meat is sterile to a safe degree prior to sealing, and even so it's no guarantee that food-borne pathogens won't develop. If you prep the meal yourself and detect something's amiss with the smell or flavor you can toss it out. A customer may be unaccustomed and devour something really bad. I think it's especially risky with ground meat since its a more complex process and therefor more chances of contamination.

This is inaccurate. If the meat is cooked at sufficient temperature (about 130 C), no new pathogens will develop. Furthermore, if it is cooked sufficiently long (and that depends on the temperature), there will be a pathogen reduction equivalent (or better after that period of time) to cooking at a higher temperature. It is up to the cook how much reduction you want. If you cook for a very long time, the reduction can be better (basically pasteurization) then typical traditional methods.

You comment only applies if the cooking period is not sufficient to achieve a reduction or if the temperature is not above 130. Baldwin, and others, provide charts with times to achieve sufficient reduction. Sous-vide doesn't assume anything, but the chef does have choices to make.

In the case here, he could cook his hamburger at 130 and aim for a 7D reduction (which is much higher then the normal target reduction, but given the source of the meat, might be wise), but it would take quite a period of time.

It's like the difference between vat pasteurization and ultra-pasteurization. One is lower heat for a longer time and the other is very hot for a short time.

Okay, now I feel silly. Although Baldwin mentions 130 deg F, it only discusses E. coli.
I felt last night that maybe I should pose this as a question.
Yep.

Thanks for the correction!