Food & Vac Series Part 5: Putting it Into Practice, LET’S MEAT!
We now know from industry professionals, based on an abundance of recently published articles, that applying vacuum to proteins with marinades and brines enhances flavor, tenderness, and processing time. While marinades and brines differ, the pulsed vacuum impregnation (PVI) mechanisms can be utilized with both in the same way. Apply vacuum, release it, repeat, and rest. Exercising the vacuum allows the surrounding liquid to be sucked in and pushed out, penetrating deeper each time, and resting at the end allows the meat to relax and absorb it. If done too aggressively, too many times, or for too long, the proteins may denature excessively, resulting in an unpleasant texture. I’ve emphasized this point with many words, but it ultimately boils down to four simple factors that require attention: vacuum level, duration of vacuum application, number of repetitions, and resting.
Level
For our purposes, the vacuum level will simply refer to the position of the needle on the vacuum gauge. It starts at 0 with no vacuum applied and goes to -30 inHg at full vacuum (at sea level). We can keep this straightforward and use “low, med, high, full” to indicate the desired vacuum level. Don’t worry too much about the numbers; just give it a try and make adjustments as you experiment. Have fun and enjoy the process!
Image is for sea level reference
*Note on vacuum levels: Full vacuum at sea level is -29.92 inHG. However, the ambient atmosphere loses 1 inHG for every 1,000 feet of elevation, making the full vacuum at 1,000 feet -28.92 inHG.
Keep this sliding scale in mind for your location because, at 5,000 feet, I’m already well into the low range, where my 0 is actually -5 inHg at sea level, and my -25 is a full vacuum. If this doesn’t make sense (it shouldn’t, so don’t feel bad; it’s weird and confusing), please see the blog post “What The Vacuum Gauge Says” for more information on why the gauge says what it says.
Duration
Just like the vacuum level, the density of the protein is crucial, as is the size of the cut, which must be factored into the duration consideration. Large cuts of meat will require more time for the vacuum to penetrate deeply, while smaller, short-fiber proteins will be faster. Intervals of 5-10 minutes are ideal for small to medium-sized proteins, while 30 to 60 minutes are suitable for larger chunks like brisket and pork butt.
Repetitions
This is the heart of Pulse Vacuum Impregnation (PVI). With each repetition, the next one will penetrate deeper and more fully than the last, reducing the amount of time needed for brining and marinating. Two to three repetitions are usually sufficient, but if you want to try more, reduce the duration of each repetition. More is beneficial, but too much can be destructive.
After loading the contents into the chamber, place the lid on, and slowly apply the vacuum until you reach the target level. Close the valve to the pump to maintain the contents at the target vacuum level for the specified duration. Once the time has passed, release the vacuum very slowly. After equalization, wait 2-3 minutes before repeating the Process. Use this short break to move the contents around in the marinade or brine. Then, put the lid on and repeat.
Resting
This is key for the best results. Slowly releasing the vacuum and waiting briefly between repetitions allows the DRP to exercise fully. Then, an extended 15-60-minute rest following the final repetition allows everything to settle.
COOKING EXAMPLES
Steak - Flank & Flat Iron
Level: high-full Duration: 5 min Reps: 3 Rest: 15 min
Steak (cut) - Low Quality
Level: med-high Duration: 2-5 min Reps: 2-3 Rest: 15 min
Steak (cut) - High Quality
Don’t do it, cook it properly!!!
Brisket
Level: high-full Duration: 10 min Reps: 3-4 Rest: 30-60 min
Pork - Loin
Level: med-high Duration: 10 min Reps: 2 Rest: 20 min
Pork - Butt
Level: high-full Duration: 15 min Reps: 2-3 Rest: 30 min
Chicken - Wings
Level: low-med Duration: 5 min Reps: 2 Rest: 10 min
Chicken - Breast & Thigh
Level: med Duration: 5 min Reps: 2 Rest: 10 min
Chicken - Whole
Level: med-high Duration: 5-7 min Reps: 2-3 Rest: 15-20 min
Turkey
Level: med-high Duration: 10 min Reps: 3 Rest: 60 min
Fish
Level: low Duration: 2 min Reps: 2-3 Rest: 10 min
Pickled - Onions
Level: med Duration: 10 min Reps: 1 Rest: 10 min
Infusions
Level: high-full Duration: 20 min Reps: 3 (stir) Rest: to cool
IMPORTANT NOTES:
Do NOT Overfill: The vacuum port where the pump connects must remain clear, maintaining sufficient space between the contents and the port. Many materials can swell and expand unexpectedly, so it’s crucial not to overfill the chamber. Doing so could draw the contents into the pump, potentially damaging it.
Do NOT Put Sealed Bags Into the Chamber. If a bag is used to hold contents in the chamber, it must be left open. There is no need to seal or close the bag. If a bag is closed and a vacuum is applied, it will swell and burst, making a big mess and being drawn into the pump, potentially causing damage and ruining it.
Do NOT Use Warm Liquids: Never use warm marinades, brines, or liquids. It’s obviously unsafe for food safety, but it will also cause a significant problem in the chamber. The contents will erupt into high-energy boiling and get sucked into the pump, ruining it.
Food Safety: Throughout the process, proper food environments (food safety temperature ranges and durations) must be maintained to ensure food safety. The entire chamber can be placed directly in the fridge to remain cool.