Ultrasonic cutting in the food industry

- Jan 19, 2020-

Ultrasonic cutting Ultrasonic cutting can cut cakes, pies, cheese, pizza, bread, candy and other foods, and the cut surface is clean and flat. When cutting foods like nuts or raisins with ultrasonic equipment, it can produce finer breakage than conventional cutting processes. Therefore, ultrasonic cutting food has more advantages than the traditional method: the cutting surface is clean and flat, the cutting knife has a longer service life, and more importantly, it can reduce the time of production stoppage due to cleaning and maintenance.


  1. the principle of ultrasonic cutting


The principle of an ultrasonic cutter is different from that of a conventional one. The principle of ultrasonic cutting is to convert 50/60 Hz current into 20, 30 or 40 KHz electric energy through an ultrasonic generator. It is converted into mechanical vibration of the same frequency, and then the mechanical vibration is transmitted to the cutting blade through a set of amplitude modulator devices that can change the amplitude. The cutter transfers the received vibrational energy to the cutting face of the workpiece to be cut, in which the vibrational energy is cut by activating the molecular energy of the rubber molecule and opening the molecular chain. This is particularly effective for cutting viscous and elastic materials, frozen materials such as food, rubber, etc., or objects that are inconvenient to apply pressure. Ultrasonic cutting also has a great advantage in that it has a fusion at the cutting point while cutting. The cutting site is edged to prevent loosening of the material being cut (eg, textile material flash). The use of ultrasonic cutting machines can also be extended, such as digging holes, shovel digging, scraping paint, engraving, slitting, etc.


  2.the basic structure and characteristics of ultrasonic cutting


Ultrasonic cutting machine is a kind of equipment that uses wave energy for cutting. Its big feature is that cutting does not use cutting edge. Or, instead of the cutting edge in the traditional sense. Conventional cutting uses a sharp-edged tool to press against the material being cut. This pressure is concentrated at the cutting edge, and the pressure is very large, exceeding the shear strength of the material being cut. The molecular combination of the material is pulled apart and cut. Since the material is pulled hard by the strong pressure, the cutting edge of the cutting tool should be very sharp, and the material itself must withstand relatively high pressure. It is not good for soft and elastic materials, and it is more difficult for viscous materials.

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The basic components are an ultrasonic transducer, a horn, a cutting blade (tool head), and a driving power source. The ultrasonic drive power source converts the commercial power into a high-frequency high-voltage alternating current and transmits it to the ultrasonic transducer. An ultrasonic transducer is actually equivalent to an energy conversion device that converts input electrical energy into mechanical energy, ie, ultrasonic waves. Its manifestation is that the transducer moves back and forth in the longitudinal direction. The frequency of the telescopic motion is equivalent to the frequency of the high frequency alternating current supplied by the driving power source. The role of the horn is to fix the entire ultrasonic vibration system and to amplify the output amplitude of the transducer. The cutting blade (tool head) further enlarges the amplitude on the one hand and focuses the ultrasonic wave. On the other hand, the ultrasonic wave is output, and the ultrasonic energy is concentratedly input to the cutting portion of the material to be cut by using a similar cutting edge of the cutting blade. Under the action of huge ultrasonic energy, this part softens and melts instantly, and the strength is greatly reduced. At this time, as long as a small cutting force is applied, the purpose of cutting the material can be achieved. Similar to conventional cutting, the basic components required are a cutter and an anvil, and the ultrasonic cutter has two basic structures.