Preparing and marinating some foods under a strong vacuum can shorten preparation time or give the food a different flavor. The cells in the food contain little bags of water called vacuoles. When the pressure is reduced these bags swell up and pop, releasing the water. When pressure is reapplied, the vacuoles will then soak up any liquid in the area. Replacing the water with different marinades can intensify the flavor. It's also possible to pickle vegetables in about a minute.
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Step 1: Marinading Fruit With Maple Syrup.
- Marinated in syrup.
- Placed in the vacuum but without syrup.
- Marinated in syrup in the vacuum.
There was a noticeable change in the apples. The apples marinated using the vacuum became slightly translucent and noticeably shrunken. They had a darker color from the syrup they soaked up after the pressure was restored and the maple taste was stronger when compared to the slices just soaked in syrup. The texture of the apples wasn't much changed by the vacuum and still had good snap. In the future I will try leaving them in the vacuum longer and then cooking with them.
What didn't work
As you can see from the pictures, the bananas and the strawberries were slightly darker but there wasn't a noticeable taste difference between the slices run through the vacuum and those not. The vacuumed bananas were softer and apparently soaked up some syrup--you can see from the picture that they oozed more syrup when sitting on the plate.
Here is a short video of the strawberries under the vacuum. You can see the maple syrup boiling and water boiling off the plain strawberries.
Step 2: Pickle Cucumbers in a Minute
- Slice up a cucumber. Thickness matters: when the vacuoles burst the flesh on the surface of the cucumber becomes softer. If the cucumber slices are thin then most of the flesh will be soft. For thicker cucumbers the inside will still stay firm, giving your pickles some "snap" when you bight into them.
- Make your favorite pickling brine like this one. To keep the brine from boiling in the vacuum chamber chill it to just above freezing.
- Drop the cucumber slices in the brine and put them in the vacuum chamber. It should take about a minute for the cucumbers to soak up enough brine to make them pickles.
Step 3: Marinading Tomatoes in Balsamic Vinegar
Tomato slices will soak up a lot of liquid in a vacuum. The downside is that they become noticeably softer and not everybody will like the mouth-feel even though the taste is stronger. Use a quality balsamic vinegar or else the vinegar will overpower the tomato. Like the pickles, chill the vinegar to prevent it from boiling.
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