Principle of ultrasonic plant essential oil extraction equipment / extractor
Ultrasound is an effective method to destroy the cell structure. The effect can be used to extract the substance in the cell. For example, starch is extracted from the cell matrix.
L ultrasonic waves produce alternating high and low pressures in exposed liquids. During the low pressure cycle, ultrasonic produces small vacuum bubbles in liquid, and the vacuum bubble breaks sharply during the high pressure cycle. This phenomenon is called cavitation. The explosion of cavitation bubble causes strong hydrodynamic shear force.
The shear force can break down the fiber and fiber like materials into cell particles and destroy the structure of cell wall. This releases substances, such as starch and sugar, from the cells into a liquid. In addition, the cell wall material is broken into small fragments.
The effect can be used in fermentation, digestion and other conversion processes of organic matter. After Microgrinding and grinding, ultrasonic waves convert more substances in cells, such as starch and cell wall fragments into sugar and enzymes, respectively. It also increases the surface area of the enzyme in the process of liquefaction or saccharification. This usually increases the speed and yield of yeast fermentation and other conversion processes, such as increasing ethanol production of biomass.
L the ultrasonic decomposition of cell structure (cleavage) is used to extract compounds from inactivated microbial cells.
When liquid is treated with high intensity ultrasound, the sound wave transmitted to the liquid medium will produce alternating high pressure (compression) and low pressure (sparse) cycles, and its rate depends on frequency. During the low pressure cycle, high-intensity ultrasonic will produce small vacuum bubbles or voids in the liquid. When bubbles reach the volume of energy that can no longer absorb, they collapse violently in high pressure cycle, which is called cavitation. During the explosion, a very high temperature (about 5000K) and pressure (about 2000atm) will be reached locally. The collapse of cavitation bubble also leads to the liquid jet velocity of up to 280m / s. The shear force produced mechanically destroys the cell membrane and improves the material transfer. According to the ultrasonic parameters, ultrasonic has destructive or constructive effects on cells, depending on the ultrasonic parameters used.
cell division
Under the strong ultrasound, enzymes or proteins can be released from cells or subcellular organs, which is the result of cell division. In this case, the compounds dissolved into solvents are enclosed in an insoluble structure. In order to extract it, the cell membrane must be destroyed. Cell destruction is a sensitive process because the cell wall has the ability to withstand the internal osmotic pressure. Good control of cell destruction is needed to avoid hindering the release of products (including cell fragments and nucleic acids) or product denaturation.
Ultrasonic extraction is a good control method for cell decomposition. Therefore, the mechanical effect of ultrasonic provides faster and more complete cell materials for penetrating solvent and improves the transfer quality. Ultrasonic can penetrate into plant tissue and improve quality transmission. Ultrasonic cavitation breaks cell wall and promotes matrix release.
mass transfer
The mechanical activity of ultrasonic supports the diffusion of solvents into the tissue. When ultrasonic wave mechanically destroys cell wall by cavitation shear force, it promotes the transfer from cell to solvent. The surface area of the contact between solid and liquid phase is increased by reducing the particle size caused by ultrasonic cavitation.
Protein and enzyme extraction
Especially, the extraction of enzymes and proteins stored in cells and subcellular particles is a unique and effective application of high intensity ultrasound. Because the extraction of organic compounds from plants and seeds can be significantly improved by solvent. Therefore, ultrasound has potential benefits in the extraction and separation of new potential bioactive components. For example, from unused by-product logistics formed in the current process.
Lipids and proteins
Ultrasound is often used to improve lipids and proteins extracted from plant seeds, such as soybeans (such as flour or degreased soybeans) or other oil seeds. In this case, the destruction of cell walls promotes pressing (cold or hot), thereby reducing the residual oil in the cake.
Ultrasonic can support almost any commercial production capacity, hydrophilic soybean protein, when using thicker slurry, the required ultrasonic treatment energy is very low.
It is suitable for: citrus oil, mustard oil, peanut rape, herbal oil (Echinacea), rape seed oil, soybean oil, corn oil, etc.
Phenols and anthocyanin release
Enzyme, if the enzyme, cellulase and hemicellulase are widely used in juice treatment, to reduce the performance of cell wall and improve the extraction rate of juice. Destruction of cell wall matrix also releases some components, such as phenols, into juice. Ultrasonic improves the extraction process, so it can lead to the increase of phenol compounds, alkaloids and juice production, usually in filter cake.
The ultrasonic treatment has a beneficial effect on the release of phenols and anthocyanins in grape and berry matrix, especially from the blueberry (Vaccinium) and Ribes nigrum to fruit juice. The concentration of phenol compounds in the juice of blueberry juice can be increased by more than 15% by ultrasonic treatment.
Microbial and enzyme inactivation
Microorganisms and enzymes inactivate (preserve), such as juice and sauce, are another application of ultrasonic in food processing. Today, increasing temperature in a short time (pasteurization) is still the most common treatment method for microorganisms or enzymes in the process of inactivation, thus prolonging the preservation time. Because of high temperature exposure, this high temperature sterilization is often unfavorable to many foods. The quality of food may be reduced by the formation of new materials and macromolecules by thermal catalysis, as well as the deformation of plant and animal structures. Therefore, heat treatment may lead to a less ideal sensory attribute, namely texture, flavor, color, odor and nutritional quality (vitamins and proteins). Ultrasound is an effective alternative to non heat treatment.
The heat produced by cavitation and local free radicals can lead to the inactivation of enzyme in ultrasonic treatment. Under the treatment of low enough ultrasound, structural and metabolic changes can occur in cells without damage. The activity of peroxidase related to odor and browning pigment increase was found in most raw and immature fruits and vegetables, which can be reduced by ultrasonic. Enzymes, such as lipases and protease, can resist high temperature treatment, reduce the quality and storage life of heat treated milk and other dairy products. Ultrasonic treatment is used while using high temperature and pressure (MTS) to inhibit its activity more effectively.
Ultrasound has shown its potential in destroying food borne pathogens such as E.coli, Salmonella, Ascaris, giargia, Cryptosporidium cyst and poliovirus.
Suitable for: preservation of jam or ingredients, such as ice cream, juice and sauce, meat products, dairy products, etc.