Overnight power outage during SV

[DaveD]

Hey folks, yesterday in the early afternoon I put a beef eye round roast vac-sealed in the sous vide as the next piece for lunchmeat making, running at 132/56, with the plan to run it about 30 hours. Overnight we had a power outage of a couple of minutes, enough to stop the SV. By the time I got up and realized it, the water temp had drifted down to 82/28.

Now, the cut spent at least 12 hours at 132/56 before this, which is way more than enough time for everything to be food safe. Nothing could get into that bag - still sealed and immersed in water. I reset the SV and it's back at target temp, and I'm inclined to roll with this, I don't see how anything could compromise the safety here, but figured I would check with the hive mind. Whaddaya think??

[STEbbq]

I don’t see issues Dave.

[Bkhuna]

By 12 hours the meat is pasteurized. Inside a bag with no leaks you are good to go.

[DaveD]

This is my reasoning as well. And I assume that's a typo and you meant *no* leaks...

[Bkhuna]

DaveD Thanks.

[WI Bubba]

It would be enough to make me wonder, and if I'm wondering, I'm tossing it. My gut says you are okay. Then again it won't be my guts that tell me that you are not okay.

Jerod Broussard would be the one that I would trust to make the yay or nay call on this one.

[Jerod Broussard]

I just woke up.....my gut feels good about it.

[Draznnl]

I’d finish cooking it and eat it. I’m no food scientist, Dave, but I too think it’s pasteurized.

[SheilaAnn]

Go for it. I trust you have good food handling practices prior to sealing.

[DaveD]

You know it!

[Duanessmokedmeats]

Eat a few slices and get back to us in 3 days...if you can.

[Sid P]

Ugh, that happened to me a couple years ago. I’m sure it’s fine to eat.

[MBMorgan]

I'd be careful, Dave. There are some pathogens that are able to encapsulate themselves into spores. Those little nasties (once in their spores) are NOT killed at typical SV temps and once things cool down a bit, they are able to "reanimate" and resume multiplication and production of toxins. Hence the need to chill SV items rapidly to a temp below which all that unpleasantness can happen.

Here's an excerpt from an excellent 2008 paper (since regularly updated) by Douglas Baldwin, PhD (once ... and possibly still ... a member here in the AR Pit) that addresses the issue:

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"Pathogens of Interest


Sous vide processing is used in the food industry to extend the shelf-life of food products; when pasteurized sous vide pouches are held at below 38°F (3.3°C), they remain safe and palatable for three to four weeks (Armstrong and McIlveen, 2000; Betts and Gaze, 1995; Church, 1998; Creed, 1995; González-Fandos et al., 2004, 2005; Hansen et al., 1995; Mossel and Struijk, 1991; Nyati, 2000a; Peck, 1997; Peck and Stringer, 2005; Rybka-Rodgers, 2001; Simpson et al., 1994; Vaudagna et al., 2002).

The simplest and safest method of sous vide cooking is cook-hold: the raw (or partially cooked) ingredients are vacuum sealed, pasteurized, and then held at 130°F (54.4°C) or above until served. While hot holding the food will prevent any food pathogens from growing, meat and vegetables will continue to soften and may become mushy if held for too long. How long is too long depends on both the holding temperature and what is being cooked. Most foods have an optimal holding time at a given temperature; adding or subtracting 10% to this time won't change the taste or texture noticeably; holding for up to twice this time is usually acceptable.

For cook-hold sous vide, the main pathogens of interest are the Salmonella species and the pathogenic strains of Escherichia coli. There are, of course, many other food pathogens but these two species are relatively heat resistant and require very few active bacteria (measured in colony forming units, CFU, per gram) to make you sick. Since you're unlikely to know how contaminated your food is or how many of these bacteria your (or your guests) immune system can handle, most experts recommend a 6.5 to 7 decimal reductions of all Salmonella species and a 5 decimal reduction of pathogenic E. coli.

The most popular methods of sous vide cooking are cook-chill and cook-freeze – raw (or partially cooked) ingredients are vacuum sealed, pasteurized, rapidly chilled (to avoid sporulation of C. perfringens (Andersson et al., 1995)), and either refrigerated or frozen until reheating for service. Typically, the pasteurized food pouches are rapidly chilled by placing them in an ice water bath for at least the time listed in Table 1.1.

For cook-chill sous vide, Listeria monocytogenes and the spore forming pathogenic bacteria are our pathogens of interest. That's because Listeria is the most heat resistant non-spore forming pathogen and can grow at refrigerator temperatures (Nyati, 2000b; Rybka-Rodgers, 2001), but appears to require more bacteria to make you sick than Salmonella or E. coli. Most experts recommend a 6 decimal reduction in Listeria if you don't know the contamination level of your food.

While keeping your food sealed in plastic pouches prevents recontamination after cooking, spores of Clostridium botulinum, C. perfringens, and B. cereus can all survive the mild heat treatment of pasteurization. Therefore, after rapid chilling, the food must either be frozen or held at

1. below 36.5°F (2.5°C) for up to 90 days,
2. below 38°F (3.3°C) for less than 31 days,
3. below 41°F (5°C) for less than 10 days, or
4. below 44.5°F (7°C) for less than 5 days

to prevent spores of non-proteolytic C. botulinum from outgrowing and producing deadly neurotoxin (Gould, 1999; Peck, 1997).

A few sous vide recipes use temperature and time combinations which can reduce non-proteolytic C. botulinum to a safe level; specifically, a 6 decimal reduction in non-proteolytic C. botulinum requires 520 minutes (8 hours 40 minutes) at 167°F (75°C), 75 minutes at 176°F (80°C), or 25 minutes at 185°F (85°C) (Fernández and Peck, 1999). The food may then be stored at below 39°F (4°C) indefinitely, the minimum temperature at which B. cereus can grow (Andersson et al., 1995). While O'Mahony et al. (2004) found that the majority of pouches after vacuum packaging had high levels of residual oxygen, this doesn't imply that the Clostridium species – which require the absence of oxygen to grow – aren't a problem since the interior of the food often has an absence of oxygen. Most other food pathogens are able to grow with or without oxygen."
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Here's a link to the full paper: https://douglasbaldwin.com/sous-vide.html

[DaveD]

Wow, thanks for this!! Lots to unpack here. Much appreciated.

[Oak Smoke]

MBMorgan Thank you. I’ve been uneasy with SV but had no evidence that its time-temp claims could leave bad operators able to survive. Now I have a much better understanding of how to handle the few things I SV. I”m still comfortable resting meats I’ve taken to the 203 F range because they are truly sterile.