Ultrasounds in cooking
Ultrasonic food processing is a technology which attains the following effects:
Mixing and homogenization;
Emulsification;
Extraction;
Dissolution;
Degasification;
Softening (meat);
Aromatization;
Cutting;
Functionalization and modification of intermediate products and end products of the food making process.
All these processes are realised through the cavitation phenomenon; however other effects on food are possible and can be experimented.
In particular, new frontiers of cooking at low temperature may be opened up with special ultrasound treatments.
Aromatization of wine and spirits with wood chips
UAE (Ultrasound Assisted Extraction) can be used not only for plant extractions but also for aromatization processes. For example, to obtain the release of tannins and other polyphenols in wine or other alcoholic product in a few minutes, in order to simulate aging in barrique.
Material:
- Generic red wine
- Unflavored spirit (grappa)
- Oak wood chips
- Cherry wood chips
Procedure :
The chips were used both whole and chopped to quantify the release of tannins and other polyphenols based on the product format.
- Samples: 10 g of chips in 80 ml of solvent
- Test performed with a system consisting of a 100 ml US reactor
- US settings: frequency 22 kHz, Power 100W
- Sonication time: 15 minutes
- Process Type: BATCH
- Max Process temperature: 60 ° C
Results
Pictures indicate (oak chip sonication tests):
- wine and grappa as they are (left)
- sonicated wine and grappa with whole wood chips (center)
- sonicated wine and grappa with chopped chips (right)
As visible from the pictures, the release is really important, this is also perceived organoleptically both by tasting and by smell. As could be imagined, with a larger surface exposed to the action of the US, a greater extraction is also obtained, this can be seen from the last 2 photos of the two sequences, where the product is darker.
Example of emulsion and homogenizing
Ultrasound can be used to obtain stable homogenizations and emulsions, even in the food sector.
Some examples can be:
- emulsion of oil with vinegar
- emulsion of eggs with other liquids
- preparation of mousses, sweet creams or salty routes
Culinary ultrasound systems
Everywave manufactures compact ultrasound systems GET:WAVE which sonicate liquid preparations in containers of various type. The specific sonicating power is easily changed (Watt/litre) according to the application and the user’s needs. Moreover, the generator Titako allow to control all process parameters , like the operating temperature
Aromatization of oil by ultrasound
The ultrasound systems produced by Everywave can be used to naturally aromatize vegetable oils, of great interest for the food market.
Here are some examples of tests carried out at Everywave laboratory, aimed at optimizing the process of flavoring olive oil with fresh vegetables:
- lemon peel (without albedo)
- basil
- garlic
Since a particularly high specific sonication power is not required for this application, it was decided to use the 5 liter US-tank, with internal mixing, 500W power, 25kHz frequency, but the process can also be carried out with the other Everywave products.
Due to its natural viscosity, olive oil needs a treatment of a few hours to absorb the aromas from the vegetables, also because the process must be carried out at temperatures that never exceed 30°C, so that they do not alter the organoleptic properties of the oil.
Max sonication temperature: 30°C
Type of process: BATCH , 3-5 hours, with mixing
| N prova | Vegetable | Time | Oil/veg. ratio | Temperature (°C) | Results |
| 1 | Lemon, mill 3 mm | 5 hours | 200gr veg. / 5 liters oil | 30 max | Delicate and persistent aroma in the mouth, suitable for sweet and savory foods |
| 2 | Basil, mill 3 mm | 3 hours | 100gr. veg. / 5 liters oil | 30 max | Intense aroma, suitable for various types of dressings (salad, pasta) |
| 3 | Garlic, mill 3 mm | 1 hour | 50gr. veg. / 5 liters oil | 30 max | Very intense and persistent aroma, suitable for pasta, vegetables and meats |
Note: the olive oil used had a very intense aroma that made the perception of the aromas of the vegetables more complex.
Particularly satisfying was the flavoring with garlic, followed by basil and finally lemon, with a delicate scent both in the mouth and nose. Lemon could also be interesting for an application in the confectionery field.
