What causes the sous vide meat to become "mealy"? An enzyme?

[torolover]

I sous vide this pork shoulder for 72 hours at 140F with no salt or marinade.  As you can see from the picture, the texture is mealy.  It kind of has this grainy, dusty texture.

 

I know from experience if I want less "mealy" meat, I should only sous vide for 24 hours, or maybe 48 hours max.  At higher temps it seems to be less mealy as well.

 

What causes this mealy texture? Is it the enzyme that Douglas Baldwin wrote about?     "Moreover, the sarcoplasmic protein enzyme collagenase remains active below 140°F (60°C) and can significantly tenderize the meat if held for more than 6 hours (Tornberg, 2005)."

 

 

Does this mean the enzyme is only active at temps below 140F?  So if I sous vide the pork shoulder at 145F instead of 140F, for 72 hours, it won't be mealy?

Edited January 16, 2015 by torolover (log)

[johnder]

Did you salt the meat before bagging?   If so that would cause is to have some breakdown in texture.  But mainly, 72 hours is a loooong time for a shoulder. You may be better off bumping it up to 62/63c for 24 hours.

[Anna N]

The other issue with pork is that an awful lot of it is preseasoned (translation BRINED) in which case......

[KennethT]

Plus, pork shoulder is a collection of muscles. Some of the muscles have lots of connective tissue and fat, and some are quite lean and tender. I believe Rotuts has extolled the virtues of taking apart a shoulder and treated different parts differently in another thread. Lean/tender meat would be very mealy at 140/72h.

[torolover]

The pork shoulder I used was fresh.  When I Sous Vide, I don't use salt or marinade.  Like I mentioned before I understand if I use higher temps and lower times, the meat won't be mealy.

 

What I'm curious is the science behind it.  Is the mealy texture caused by that enzyme?  If that enzyme doesn't exist at temps over 140F, then theoretically if I sous vide at 145F for 72 hours, meat won't be mealy.  

 

Any thoughts?

 

Thanks! 

[FeChef]

what were you trying to achieve here? For tender sliced pork shoulder i use 145F for 24-26 hours max. For pulled pork i use 155F for 30-33 hours max. I am very pleased with the results and ive probably Sous vide 20 pork shoulders using those times/temps. I also brine the shoulders for 24 hours in a 4% kosher salt solution. The pork shoulders are fresh.

[Kerry Beal]

The pork shoulder I used was fresh.  When I Sous Vide, I don't use salt or marinade.  Like I mentioned before I understand if I use higher temps and lower times, the meat won't be mealy.

 

What I'm curious is the science behind it.  Is the mealy texture caused by that enzyme?  If that enzyme doesn't exist at temps over 140F, then theoretically if I sous vide at 145F for 72 hours, meat won't be mealy.  

 

Any thoughts?

 

Thanks! 

I think that is correct - it may completely and totally fall apart - but if the enzyme is responsible for mealy - it won't be mealy.  Of course an experiment may be in order to prove it.

Edited January 17, 2015 by Kerry Beal (log)

[EnriqueB]

The pork shoulder I used was fresh.  When I Sous Vide, I don't use salt or marinade.  Like I mentioned before I understand if I use higher temps and lower times, the meat won't be mealy.

 

What I'm curious is the science behind it.  Is the mealy texture caused by that enzyme?  If that enzyme doesn't exist at temps over 140F, then theoretically if I sous vide at 145F for 72 hours, meat won't be mealy.  

 

Any thoughts?

 

Thanks! 

[paulraphael]

There are many other enzymes, including calpain and cathespin. These have both been shown to tenderize meat. Their peak activity levels are around 40C and 50C, respectively. They're both deactivated by 60C, but in any large chunk of meat cooked in a 60C water bath, the interior is going to spend a long time in the activity range of these (and other) enzymes.

 

Cathespin is possibly a problematic enzyme. It's been implicated as a producer of off-flavors. I don't know if it's also capable of producing bad textures. In general, I try to minimize time meat will spend in the 45C–55C range. It's one reason that SV can be tricky for anything big.

Edited January 20, 2015 by paulraphael (log)