Patent Application
20110278153
This application claims the benefit of Australian Provisional Patent Application No. 2008903844 filed 29 Jul. 2008 which is incorporated herein by reference in its entirety.
The present invention relates to apparatus and systems for use in methods of viscosity reduction of liquid and semi-liquid products by application of ultrasonic energy. For example the invention relates to the application of highly propagating ultrasonic energy to a food, beverage or non-food product to temporarily or permanently reduce viscosity of that product.
Viscosity of liquid and semi-liquid products is an important factor affecting processing and quality of end products. There are a limited number of ways to reduce viscosity in food and beverage products. Temperature effects on viscosity are only achieved when the product is maintained at a certain temperature typically an elevated temperature. Once the heating source is removed viscosity quickly reverts to its original level. In addition heating impacts negatively on quality, flavour and texture of some food products.
Chemicals and enzymes may be used to manage viscosity but typically represent a permanent way to reduce viscosity. However, chemical and enzyme additives to reduce viscosity are expensive and undesirable in food and beverage products formulated for human or animal consumption.
A conventional ultrasonic bath produces ultrasonic energy in the form of a standing wave such that when a liquid or semi-liquid product is placed in the bath the pattern of viscosity reduction shows alternating zones of partially reduced viscosity and other zones in which viscosity is not been affected. In order to achieve a greater effect in viscosity reduction the product must be moved relative to the standing wave which can be impractical for large volumes of product. Furthermore, conventional ultrasonic baths produce energy waves that dissipate very quickly with distance and do not propagate through viscous or high percentage solid products.
Accordingly there exists a need in the art for improved apparatus, systems and methods for use in viscosity reduction.
In a first aspect of the invention there is provided a method for reducing the viscosity of a product by applying highly propagating ultrasonic energy to said product, the method comprises
contacting at least a portion of said product with an highly propagating ultrasonic energy emitting assembly; and
emitting highly propagating ultrasonic energy from the assembly into the product thereby reducing the viscosity of the product.
The method may further comprise the step of clarifying the reduced viscosity product by centrifugation.
The method may further comprise the step of exchanging heat from the reduced viscosity product in a heat exchanger.
The method may further comprise the step of deaerating, degassing, deodourising or cooling the reduced viscosity product.
The method may further comprise the step of dispensing the reduced viscosity product into at least one container.
The method may further comprise the step of pasteurising the reduced viscosity product.
The method may further comprise the step of dispensing the pasteurised reduced viscosity product into at least one container.
The method may further comprise the step of filtering the reduced viscosity product. The filtering may be reverse osmosis filtration, ultrafiltration, microfiltration, crossflow filtration or any combination thereof.
The product may be a molten product and the method may further comprise the step of dispensing the reducing the viscosity molten product.
The method may further comprise the step of homogenising the reduced viscosity product.
The product may be a liquid coating product and the method may further comprise the step of dispensing the reduced viscosity liquid coating product.
The method may further comprise the step of spray drying the reduced viscosity product.
The method may further comprise the step of cooking the reduced viscosity product wherein the reduced the viscosity of the product allows enhanced heat transfer during cooking.
The emission of highly propagating ultrasonic energy into the product may generate cavitation in the product thereby reducing the viscosity of the product. The cavitation may generates heat in the product.
The reduction of viscosity may be permanent or temporary.
The frequency of the highly propagating ultrasonic energy may be between about 16 kHz to about 24 kHz, with an energy density of between about 0.0001 W/cm3 to about 30 W/cm3. The amplitude of the highly propagating ultrasonic energy may be between about 0.1 to about 150 microns. The highly propagating ultrasonic energy may be applied over a period of time between about 0.001 second to about 10 minutes.
The highly propagating ultrasonic energy may be applied in addition to viscosity reduction methods selected from the group comprising heat, chemicals, enzymes, mechanical homogenisation, or any combination thereof.
The product may be selected from the group consisting of products comprising milk, yogurt, cheese, whey protein, custard, cream, juices and concentrates, smoothie blends of juices and dairy products, oils, sauces, mayonnaise, hydrocolloid materials, wine and wine concentrates, soya protein isolate, dairy proteins, yeast extracts, starch (e.g. potato or corn starch), soya beans, sugar and dextrose syrups, jams, maple syrups, honey, sauces, tea/coffee extracts, sugar beverages, artificial sweetner beverages, fruit cordials, marmalade, syrups, soups, canned soups, beverages, brine solutions, coatings, aqueous and non aqueous liquids, beer, spirits, infant milk nutritional formula, agricultural flow stream, agricultural extracts, any food/beverage containing hydrocolloids or oils, fermented products, adult milk nutritional formula, cosmetics health care products, tooth paste, mouthwash, facial cream, hand cream, body creams, shampoo, conditioner, soaps, liquid detergents, pharmaceutical, petroleum based products, oils from agricultural/animal/fish/aquatic/mining/organic products, fermentation flow streams, petroleum oils, thermoset resins, plastic monomers, polymeric materials.
In another aspect the invention provides a highly propagating ultrasonic energy apparatus for reducing the viscosity of a product, the apparatus comprises:
at least one highly propagating ultrasonic energy emitting assembly; and
a container adapted to contain the product wherein, in use highly propagating ultrasonic energy is emitted from the assembly and is applied to the product in the container.
At least a portion of the highly propagating ultrasonic energy emitting assembly may be within the container. The highly propagating ultrasonic energy emitting assembly may be mounted to the container.
At least a portion of the highly propagating ultrasonic energy may be applied to the container via a fluid medium.
In a further aspect the invention provides a system for reducing the viscosity of a product, the system comprises:
at least one means for emitting highly propagating ultrasonic energy; and
a means for containing the product; and wherein during operation the assembly emits highly propagating ultrasonic energy into the product thereby reducing the viscosity of the product.
The system of may further comprise a centrifuge means, a heat exchanging means, a deaerator means, a deodouriser means, a flash cooling means, a pasteurisation means, a filtration means, a dispensing means, a homogenisation means or any combination thereof.
The term “highly propagating ultrasonic energy” includes within its meaning ultrasonic energy emitted substantially orthogonal to the axial direction of a sonotrode. The term “comprising” means including principally, but not necessarily solely.
Furthermore, variations of the word “comprising”, such as “comprise” and “comprises”, have correspondingly varied meanings.
As used in this application, the singular form “a”, “an” and “the” include plural references unless the context clearly dictates otherwise. For example, the term “a surface” also includes a plurality of surfaces.
As used herein, the term “synergistic” refers to a greater than additive effect that is produced by a combination of two entities. A synergistic effect exceeds that which would be achieved by combining the effect of each entity taken alone.
The skilled person will understand that the figures and examples provided herein are to exemplify, and not to limit the invention and its various embodiments.
Conventional ultrasonic apparatus may be used to reduce the viscosity of a liquid or semi-liquid product but suffer from a number of disadvantages. For example, the use of conventional ultrasonic energy produced in a conventional apparatus creates standing waves in the product filling the apparatus so that the product will show zones of reduced viscosity in areas not bounded by the standing waves and zones where viscosity is not reduced in the regions bounded by the standing waves.
As mentioned above conventional ultrasonic cleaning bath technology/transducers are based on the formation of standing wave technology. Standing waves do not penetrate into products as the energy levels are very low. Similarly standing waves do not enhance liquid mass transfer or convective heat transfer. Furthermore the formation of standing waves results in areas exposed to the standing waves and areas that are not exposed, typically giving a 50% dead zone. Thus, in a product such as sugar syrup, the result may be that only 50% of the product has reduced viscosity.
Further, conventional systems produce energy waves that dissipate very quickly with distance and do not affect the liquid mass transfer properties of a fluid and the convective heat transfer properties and little if any possibility of penetration into viscous or high percentage solid materials. For example, a conventional sonotrode experiences a drop in energy of 95% over 10 mm from the sonotrode in a product with 30% solid material, with negligible penetration into surrounding material. The treated zone from these waves produced is not effective across a large volume of product—that is cavitation occurs in some areas and not in others.
In accordance with the present invention apparatus and methods for applying highly propagating ultrasonic energy to a product to reduce viscosity of the product are provided. The apparatus generally comprise an ultrasonic generator, at least one ultrasonic transducer arranged such that highly propagating ultrasonic energy is applied either directly or indirectly to the product. The methods of the invention generally comprise the application of highly propagating ultrasonic energy to a product to temporarily or permanently reduce the viscosity of that product. The products are typically fluids such as liquids but may also comprise at least a portion of solid, porous or colloidal material. The products may be food or beverage products formulated for human or animal consumption.
The use of highly propagating ultrasonic energy waves provide improvements over existing ultrasonic cleaning technology and sonotrode systems which include, for example:
1. enhanced working/travel distance of energy waves
2. changes to molecular structure of products
2. energy of waves maintained at long distances
3. ability of energy waves to uniformly penetrate through products
4. enhanced liquid mass transfer and convective heat transfer
A sonotrode generates ultrasonic energy typically when an alternating voltage is applied across a ceramic or piezoelectric crystalline material (PZT). The alternating voltage is applied at a desired oscillation frequency to induce movement of the PZT. The PZT transducer is mechanically coupled to the horn means which amplifies the motion of the PZT. The horn means includes a tip portion, referred to herein as a sonotrode. The assembly of the PZT horn means including the tip portion may also be referred to herein as the sonotrode. Highly propagating ultrasonic energy or HPU includes ultrasonic energy that is emitted substantially orthogonal to the axial direction of a sonotrode. Such energy propagates through a fluid medium, typically water or a gas and over a large zo distance from the sonotrode and is not limited to the areas immediately surrounding the sonotrode. After propagating through the medium the highly propagating ultrasonic energy may be applied over a surface and to penetrate into said surface.
Highly propagating ultrasonic energy waves are able to propagate across through a viscous product up to a distance of at least 50 cm to about 300 cm, or about 100 cm to about 300 cm or about 150 cm to about 300 cm or about 200 cm to about 300 cm to a contaminated surface. Highly propagating ultrasonic energy propagates substantially uniformly across volumes leaving and are able to penetrate up to up to a depth of about 0.0001-1 mm, or about 1-20 mm, or up to a depth of about 2-20 mm or up to a depth of about 5-20 mm or up to about 5-15 mm or up to about 7-10 mm into substantially solid, porous or colloidal components of a product.
In one embodiment of the present invention a combination of the high power, low frequency, long wavelength and sonotrode shape/design allows for the above effects to take place. In contrast, ultrasonic energy emitted from conventional ultrasonic cleaners has limited propagation distance from the emitting surface with a drop in energy of 90+% at a distance of 100 cm and are not uniform in their volume area or volume of the treated flow stream, and do not have the ability to penetrate into solid, porous or colloidal components of a product.
In another embodiment, the sonotrode may be arranged such that the highly propagating ultrasonic energy generated is able to propagate through a viscous product up to a distance of about 50 cm to about 300 cm, or about 100 cm to about 300 cm or about 150 cm to about 300 cm or about 200 cm to about 300 cm to the inner surface of a flow cell, conduit, vessel containing the viscous fluid, transmit uniformly throughout the whole volume leaving no single space/zone untouched from the wave energy. In addition, the highly propagating radial waves are able to penetrate up to about 5-20 mm or up to about 5-15 mm or up to about 7-10 mm or into solid, porous or colloidal components of a product suspended in the viscous flow stream or material.
In yet another embodiment, the highly propagating ultrasonic energy is emitted substantially at a right angle from the surface of a sonotrode with high energy. In this context high energy refers to a less than about 20% drop in energy and production of shear forces resulting from collapsing cavitation bubbles at a distance of about 100 to about 300 cm from the emitting sonotrode. Furthermore, in this context high energy refers to the ability of the highly propagating ultrasonic energy to propagate into solid, porous or colloidal components of a product and create cavitation internally up to a depth of about 0.0001-1 mm, or about 1-20 mm, or up to a depth of about 2-20 mm or up to a depth of about 5-20 mm or up to about 5-15 mm or up to about 7-10 mm.
In a further embodiment the highly propagating ultrasonic energy reduces the viscosity of a product thereby enhancing the kinetics of thermal conductive heat transfer into products thus allowing reduced cooking times or reduced time to pasteurize or sterilize in a retort system or improve the kill of microbiological organisms more efficiently. Both reduced cook time and reduced pasteurization time improves the quality and flavour of a food product. The highly propagating ultrasonic energy increases the rate of the heat transfer process up by about 1%-300%.
While not being limited by theory it is generally held that highly propagating ultrasonic energy reduces viscosity via generating cavitation and generating heat. Cavitation comprises the repeated formation and implosion of microscopic bubbles. The implosion generates high-pressure shock waves and high temperatures near the site of the implosion. As a result, a rapid temporary change in the polymer chain or branch structure of the product occurs. When very high ultrasonic amplitude/energy is applied, the change in the polymer chain or branch structure is permanent as in some cases the ultrasonic energy is sufficient to break the bonds of molecules. Permanent effects in chain or branch molecules result in a permanent viscosity reduction effect.
When lower ultrasonic amplitude/energy is applied, the change in the polymer chain or branch structure is temporary but eventually reverts to its original form. The time taken for the product to revert back or stay in a temporary viscosity mode is dictated by the energy and amplitude applied.
In one embodiment the ultrasonic emitting assembly or ultrasonic generator generates ultrasonic energy at frequencies between about 10 KHz and about 2000 KHz or between about 10 KHz and about 1500 KHz, or between about 10 KHz and about 1000 KHz, or between about 10 KHz and about 750 KHz, or between about 10 KHz and about 400 KHz, or between about 10 KHz and about 250 KHz, or between about 10 KHz and about 125 KHz, or between about 10 KHz and about 100 KHz, or between about 10 KHz and about 60 KHz, or between about 10 KHz and about 40 KHz, or between about 10 KHz and about 30 KHz, or between about 16 KHz and about 30 KHz, or between about 16 kHz and about 26 kHz or between about 19 KHz and about 28 KHz, or between about 16 KHz and about 22 KHz, or between about 16 KHz and about 19.9 KHz.
In one embodiment the amplitude of the highly propagating ultrasonic energy is between about 0.001 to about 500 microns, preferably between about 0.01 to about 40 microns amplitude, even more preferably between about 1 to about 10 microns.
In one embodiment the energy density of the highly propagating ultrasonic energy is between about of 0.00001 watt/cm3 to 1000 watt/cm3, between about 0.0001 watt/cm3 to about 100 watts/cm3.
In another embodiment the highly propagating ultrasonic energy is applied to a viscous fluid, food product, or a flow able material or fluid over a period of time from about 0.001 second to about 60 minutes, or from about 0.001 second to about 50 minutes, or from about 10 seconds to about 40 minutes, or from about 15 seconds to about 40 minutes, or from about 20 seconds to about 30 minutes, or from about 25 seconds to about 20 minutes, or from about 30 seconds to about 10 minutes, or from about 30 seconds to about 2 minutes or from about 0.001 second to about 1 minute or from about 0.001 second to about 10 seconds, or from about 0.001 second to about 1 second or from about 0.001 second to about 0.1 second, from about 0.001 second to about 0.01 second.
The application of highly propagating ultrasonic energy to a product can result in either a permanent or temporary viscosity reduction dependent largely on the amplitude, power level and/or time of application of highly propagating ultrasonic energy to a product.
For the purposes of this specification the term “temporary”, in the context of viscosity reduction of a product refers the reversion of the viscosity level to a level substantially that of the starting viscosity of the product after a period of time. That period of time may be from about 1 second to about 24 hrs, or about 1 day to about a week or about 1 week to about 1 month or about 1 month to about 6 months.
For the purposes of this specification the term “permanent”, in the context of viscosity reduction of a product refers to a lowering of the viscosity such that the viscosity does not revert to a viscosity substantially that of the starting viscosity of the product.
In one example of an aspect of the invention permanent viscosity reduction in a soya protein isolate occurs when the product is exposed to highly propagating ultrasonic energy of >70 microns amplitude at a power of >100 watt/cm3. In one embodiment the application of highly propagating ultrasonic energy of 75 microns amplitude to a soya protein isolate based product results in viscosity reduction that is maintained over a 6 month period. In another embodiment the application of 10 micron amplitude highly propagating ultrasonic energy to the same product results in a viscosity reduction which reverts to its original viscosity after 1 hour.
In some embodiments application of highly propagating ultrasonic energy of more than 70 microns amplitude results in permanent viscosity reduction of fruit and vegetable juices, juice concentrates, chocolate and confectionary products, cocoa liquor, oils from agricultural products (olive oil, canola oil, corn oil, soya bean oil, palm oil, coconut oil), wine and wine concentrate, brewery products, hydrocolloid products such as xanthan gum, locust bean, carrageenan, alginates, guar gum, starch dairy products such as milk, non-food products such as petroleum oils, thermoset resins, plastic monomers, polymeric materials, mining slurry such as clay/water or gypsum slurry.
While not being limited by theory it is believed that permanent viscosity reduction produced by application of highly propagating ultrasonic energy is due to permanent breakage of molecular bonds or polymer chains.
In a preferred embodiment highly propagating ultrasonic energy applied to a product for permanent viscosity reduction at about 50 W/cm3 to about 500 W/cm3 and amplitudes of between about 40 micron and about 150 microns. The highly propagating ultrasonic energy may be applied at between about 50 W/cm3 to about 400 W/cm3 or between about 100 W/cm3 to about 350 W/cm3, or between about 150/cm3 to about 300 W/cm3, or between about 200 W/cm3 to about 250 W/cm3. The amplitude may be between about 50 microns to about 140 microns, or between 60 microns to about 130 microns, or between about 70 microns to about 120 microns, between about 80 microns to about 100 microns.
In other embodiments amplitudes of highly propagating ultrasonic energy below 10 microns and energy intensity below 10 watt/cm3 result in a temporary viscosity reduction. In another embodiment application of highly propagating ultrasonic energy of 5 microns amplitude to a soya protein isolate product results in temporary viscosity reduction over a 24 hr period before reversion to original viscosity. In yet another embodiment the application of highly propagating ultrasonic energy of 1 micron amplitude is applied to the same product a viscosity reduction is achieved over <1 hour period before reversion to original viscosity.
In some embodiments temporary viscosity reduction effects after exposure to highly propagating ultrasonic energy of below 10 microns amplitude occurs in fruit and vegetable juices, juice concentrates, chocolate, cocoa liquor, starch based products, oils from agricultural products (olive oil, canola oil, corn oil, soya bean oil, palm oil, coconut oil), wine and wine concentrate, brewery products, hydrocolloid products such as xanthan gum, guar gum, locust bean, carrageenan, alginates, dairy products such as milk, any food and beverage products containing the above components and for non food products such as bio-diesel, ethanol fermentation products, petroleum oils, thermoset resins, plastic monomers, polymeric materials, mining slurry such as clay/water or gypsum slurry.
While not being limited by theory it is believed that temporary viscosity reduction produced by application of highly propagating ultrasonic energy is due to shearing and thinning from the ultrasound and/or a temporary re-alignment or change in position of molecules, polymer chains, branch molecules. In a preferred embodiment highly propagating ultrasonic energy is applied to a product for temporary viscosity reduction at about 0.0001 W/cm3 to about 30 W/cm3 and amplitudes of about 0.1 micron to about 30 microns. The highly propagating ultrasonic energy may be applied at between about 0.0001 W/cm3 to about 30 w/cm3, 0.05 W/cm3 to about 25 W/cm3 or between about 0.1 W/cm3 to about 20 W/cm3, or between about 0.5 W/cm3 to about 15 W/cm3, or between about 1.0 W/cm3 to about 30 W/cm3. The amplitude may be between about 0.1 micron to about 20 microns, or between about 0.5 micron to about 15 microns, or between about 1 micron to about 10 microns.
In one aspect the invention provides an apparatus for reducing the viscosity of a product by the application of highly propagating ultrasonic energy to the product.
One embodiment is described with reference to
Another embodiment is described with reference to
Another embodiment is described with reference to
In another aspect the invention provides a system for reducing the viscosity of a product by the application of highly propagating ultrasonic energy to the product.
One embodiment is described with reference to
Another embodiment is described with reference to
A further embodiment is described with reference to
It will be understood by the skilled addressee that the deaerator, deodouriser or flash cooler 50 may, as illustrated be connected to the outflow of the flow cell 10. In another embodiment the deaerator, deodouriser or flash cooler 50 may have no direct connection to the flow cell and the reduced viscosity product may be stored before being deaerated, deodourised or cooled.
A still further embodiment is described with reference to
A yet still further embodiment is described with reference to
It will be understood by the skilled addressee that the filter means 62 may, as illustrated be connected to the outflow of the flow cell. In another embodiment the filter may have no direct connection to the flow cell and the reduced viscosity product may be stored before being filtered.
The filter means 62 may be any filter known in the art including a reverse osmosis filter, a microfilter or an ultrafilter.
Another embodiment is described with reference to
Another embodiment is described with reference to which
It will be understood by the skilled addressee that the homogeniser means 70 may as illustrated in
Another embodiment is described with reference to
A person skilled in the art will understand that the application of highly propagating ultrasonic energy to a liquid coating product may temporarily or permanently reduce the viscosity of the product. Accordingly, in one embodiment the outflow of the flow cell 10 illustrated in
Another embodiment is described with reference to
In the apparatus and systems of the invention increased viscosity reduction may be achieved by using an automatic frequency scanning system. In one embodiment, reducing the viscosity of canola oil, the greater the organic load (concentration, viscosity) the greater the effect of oil density and shell husk surface/tissue/structure will be on the resonance frequency of that product. The ultrasonic resonance frequency is the frequency at which the highly propagating ultrasonic energy unit will deliver the greatest energy efficiency.
Apparatus and systems of the invention may also lock onto the resonance frequency of a product and re-scan for the resonance frequency periodically, (e.g. every 0.001 second) throughout the treatment process. Without resonance frequency tracking a variation of as little as 10 Hz from the resonance frequency would result in a drop in energy efficiency in the order of 10-40%. This would have a significant reduced effect on the ability to reduce viscosity.
By way of example, the resonance frequency of canola oil is 20,317 Hz where as palm oil will have a resonance frequency of 20,078 Hz.
The systems of the invention typically include a power source, a transducer converting electric energy into mechanical vibrational energy, which is transmitted into the product system via a sonotrode. The sonotrode provides highly propagating ultrasonic energy and may be made of titanium or ceramic, steel, cast alloy, or glass.
In one embodiment sonotrodes are fitted substantially longitudinally or substantially laterally within an open tank, trough or flume. Reflector shields are arranged at the base to reflect and or focus ultrasonic energy into the product flow path.
In another embodiment sonotrodes are fitted in a flow cell where the product flows either substantially directly into the face or across the face of the sonotrode. The time the product is exposed to highly propagating ultrasonic energy in the flow cell can be controlled by regulating the micro-streaming flow from the sonotrode, the flow rate, the power and size of a transducer/sonotrode, the number of transducer sonotrodes in series and parallel, flow cell geometry or any combination thereof.
The sonotrodes/transducers can be mounted or retrofitted to existing tanks, vessels (round, square, oval), troughs, pipes, flow-cells containing the product.
In some embodiments the product may be a liquid or a liquid comprising at least a portion of solid, porous or colloidal material.
In some embodiments the product may be a food product including milk, yogurt, cheese, whey protein, custard, cream, juices and concentrates, smoothie blends of juices and dairy products, oils, sauces, mayonnaise, hydrocolloid materials or any food/beverage product containing a hydrocolloid, wine and wine concentrates, soya protein isolate, dairy proteins, yeast extracts, starch (e.g. potato or corn starch or any type of starch), soya beans; sugar and dextrose syrups, jams, maple syrups, honey, marmalade, syrups, soups, canned soups, beverages, brine solutions, coatings, aqueous and non aqueous liquids, beer, spirits, infant milk nutritional formula or adult milk nutritional formula
The juices and concentrates may be selected from the group comprising juices or concentrates of orange, apple, pineapple, mango, blackcurrant, blueberry, cranberry melon, strawberry, raspberry, grape, banana, lemon, lime, grape, grapefruit, guava,)
The oils may be selected from the group comprising canola oil, corn oil, soya bean oil, coconut oil, palm oil, sunflower oil, olive oil, cotton seed oil, algae oil, nut oil, citrus peel oil or plant oil extracts.
The hydrocolloid materials may be selected from the group comprising starch, xanthan gum, gum arabic or caragenan gum or any other type of hydrocolloid
The beverages may be tea, coffee, juice, chocolate, vanilla, malt, dairy based, herbal, oil emulsion, oil, agricultural extracts based, fermented beverages, spirits, wine products, grape juice or fermented grape juice, beer, ginger beer, sugar or articial sweetner based drinks, high fructose corn syrup based drinks, dextrose based drinks, concentrates used to make carbonated drinks, fruit cordials containing artificial flavours or natural flavours, water juice blends or water fruit cordial blends, juice/dairy blends, beverages containing hydrocolloids or mixtures of all the above
In other embodiments the product may be a cosmetic or health care product including tooth paste, mouthwash, facial cream, hand cream, body creams, shampoo, conditioner, soaps or liquid detergents, powder detergents, house cleaning products, industrial cleaning products, pharmaceutical creams and products, prescription medical drugs, hospital drugs, any tablet, granular, powder or liquid health care, pharmaceutical, neutraceutical product.
In some embodiments the product may be liquid cleaning products, fermentation flow streams such as ethanol, bio-diesel, beer, wine, wine or dairy.
In other embodiments the product may be a non-food product such as petroleum oils or petroleum based or petroleum extracts, agricultural extracts, thermoset resins, plastic monomers or polymeric materials, paints, fertilizer products, varnishes, lacquers, engine oils, oils from agricultural products or oils from fish/animal/algae/aquatic products or mining ore or rock slurries such as phosphate slurry.
In some embodiments the solid material may include mineral particles such as those found in mining slurry or gypsum slurry.
In some embodiments the porous material may include fruit pulp, vegetable matter, or protein precipitates.
As disclosed herein the application of highly propagating ultrasonic energy to a product results in temporary or permanent viscosity reduction. Surprisingly, and as disclosed herein, the application of highly propagating ultrasonic energy to a product together with conventional methods of viscosity reduction produces improved viscosity reduction of a product than would be expected merely from the additive effects highly propagating ultrasonic energy and conventional viscosity reduction alone. That is, there is a synergistic effect between the application of highly propagating ultrasonic energy to a product and the use of conventional viscosity reduction methods.
As exemplified herein the application of highly propagating ultrasonic energy to reduce viscosity in conjunction with conventional viscosity reduction methods such as heat results in a greater reduction in viscosity than would be expected by the mere additive effects of heat or chemicals and highly propagating ultrasonic energy.
Similarly the application of highly propagating ultrasonic energy to reduce viscosity in conjunction with conventional viscosity reduction methods such as enzymes results in a greater reduction in viscosity than would be expected by the mere additive effects of both of enzymes and highly propagating ultrasonic energy.
While not being limited by theory it is believed that enhanced thermal kinetic transfer utilizing highly propagating ultrasonic energy for increased convective heat transfer combined with the effects of cavitation in addition to other methods of viscosity reduction changes the molecular structure of polymer chains and branch structures creates improved efficiency of both temporary and permanent viscosity reduction.
Additionally, while not being limited by theory it is believed that a synergistic method of using highly propagating ultrasonic energy and chemicals or enzymes to lower viscosity is achieved by the present invention due to the enhanced mass transfer of chemical/enzyme into the product by application of highly propagating ultrasonic energy. Furthermore, the ultrasonic energy is preferably applied to the reaction mixture at an average specific energy between 1×10−7 kWh and 1×10−1 kWh ultrasonic energy per liter reaction mixture, more preferably between 1×10−4 kWh and 1×10−2 kWh ultrasonic energy to per liter reaction mixture. Another aspect of this invention is to use low frequency/high intensity ultrasound in combination with mild heat (0° C.-60° C.) to enhance viscosity reduction. This synergistic effect between ultrasonic energy and thermal energy enhances viscosity reduction kinetics.
Another aspect of this invention is to use low frequency/high intensity ultrasound in combination with pressure (0.5 to 10 bar pressure but preferentially between 2 and 4 bar) to enhance viscosity reduction of liquid components. This synergistic effect between ultrasonic energy and pressure greatly enhances the coupling and impedance matching of the ultrasonic waves to the medium particularly when the fluid contains high solids content. The improved coupling of the waves to the product improves enhance viscosity reduction kinetics In the preferred equipment design, this present invention relates to the use of radial sonotrodes, which emit high-energy ultrasonic waves. However, other sonotrodes could be used such as high amplitude focused sonotrodes, which produce high concentration of localized cavitation bubbles around the sonotrode surface.
The present invention provides methods comprising reducing viscosity of products by applying highly propagating ultrasonic energy to the product. While not being bound by a particular theory it is believed the method works by the action of microscopic cavities collapsing and releasing shock waves, a process known as cavitation. The microscopic cavities are formed by sending highly propagating ultrasonic energy into a fluid that is in contact with the product.
The use of the apparatus of this invention in the methods of the invention are illustrated herein. For example, with reference to
With reference to
The viscosity of a product is similarly reduced by the operation of the apparatus illustrated in
The use of the systems of this invention in the methods of the invention are illustrated herein.
For example, with reference to
It will be understood by the skilled addressee that the centrifuge may, as illustrated, be a continuous centrifuge connected to the outflow of the flow cell but in another embodiment is a batch centrifuge with no direct connection to the flow cell. The reduced viscosity product may be stored before centrifugation.
Products used in this method include surimi, a lean meat product prepared from minced fish or land animals. The meat is rinsed numerous times to eliminate undesirable odours and the remaining solids are processed to form a gelatinous paste. Processing surimi using this method increases the yield and reduces wastewater as the reduced viscosity enhances production efficiencies giving yield and production improvements combined with reduced waste. Increased yields of vegetable oils, dairy products, fruit juices and soy products are also achieved using this method due to the increased efficiency of separating solids or heavy phases of the products from the liquid phase after viscosity reduction
The present invention provides a method of exchanging heat from a viscous product. With reference to
The flow of viscous fluids, such as the feed product illustrated in
As illustrated in
Products used in this method include soy protein, biofuels, vegetable oils and bioplastics or agricultural materials or extracts from agricultural materials. Exchanging from these products using this method provides increased production rates, reduced energy costs for production, reduced wastewater production and improved product quality
With reference to
It will be understood by the skilled addressee that the deaerator, deodouriser or flash cooler 50 may, as illustrated be connected to the outflow of the flow cell. In another embodiment the deaerator, deodouriser or flash cooler 50 may have no direct connection to the flow cell and the reduced viscosity product may be stored before being deaerated, deodourised or cooled.
Products used in this method include soy protein and vegetable oils. Reducing the viscosity of these products provides increased yields, improved product quality and material cost savings.
The invention also provides a method of pasteurising and dispensing a beverage or liquid food product. With reference to
After pasteurisation the product enters a second flow cell 10 wherein the viscosity of the product is again reduced by application of highly propagating ultrasonic energy before the product is dispensed into containers for further processing via a filling apparatus or dispensing means 58.
In one embodiment highly propagating ultrasonic energy may be applied to the pasteuriser 54 to increase heat transfer to the product during pasteurisation.
Products used in this method include carbonated beverages, non carbonated beverages, fruit juice, milk, milk products, sauces, pet food, baby food and canned food. Pasteurising and dispensing these products using this method provides increased production rates, better control of fill levels, reduced foaming of dispensed products, reduced energy costs, enhanced microbiological reduction performance, improved product quality, taste and texture, reduced fouling, better heat transfer, increase yield and less waste.
A person skilled in the art will appreciate that these advantages are the result of the reduced viscosity of the product as a result of the application of highly propagating ultrasonic energy. Accordingly the invention also provides a method of pasteurising and dispensing a beverage or liquid food product. For example with reference to
The invention also provides a method of filtering a product. With reference to
In one embodiment highly propagating ultrasonic energy may be applied to the filter during filtration.
It will be understood by the skilled addressee that the filter may, as illustrated in
The filter may be any filter known in the art including a reverse osmosis filter, a microfilter or and ultrafilter or cross flow steel or polymer membrane filter, ceramic filter, steel screen or polymer screen filter, any filters known in the art which have pore sizes ranging from 1000 microns in size down to 0.0001 microns in size.
Products used in this method include dairy protein, vegetable/agricultural oils, soya proteins, grape juice, fruit juices. Reducing the viscosity of these products provides increased production rates and reduced fouling kinetics.
The invention further provides a method for dispensing molten product. With reference to
In one embodiment the molten product is a polymer material going into a specifically shaped mould.
By way of example using highly propagating ultrasonic energy (4 kw unit, 19 kHz, amplitude 8 microns, radial emitting sonotrode) to reduce viscosity (65% viscosity reduction) as a pre-treatment resulted in production improvements. Dispensing the molten polymer product using this method improves product quality, reduced waste during depositing, reduced setting time, reduced energy costs.
The invention still further provides a method of homogenising a product. With reference to
It will be understood by the skilled addressee that the homogeniser 70 may as illustrated in
The invention also provides another method of homogenising a product. With reference to
It will be understood by the skilled addressee that a fluid product may comprise two or more phases of fluids of different viscosities for example, water and a concentrated sugar syrup. As viscous products do not mix efficiently the application of highly propagating ultrasonic energy to temporarily or permanently reduce the viscosity of the product will allow homogenisation of a multi phase fluid by mixing that occurs during flow of low viscosity products.
By way of example, a 10% oil, 89% water and 1% xantham gum thickener product was pre-mixed (using a mechanical mixer 500 rpm) and then homogenized/emulsified using a conventional mechanical APV homogenizer giving a mean emulsion droplet size of 0.9 microns. The same ingredients were pre-mixed with the mechanical mixer and then pre-treated with highly propagating ultrasonic energy to give a 40% reduction in viscosity (using a 2 kw unit, 10 micron highly propogating sonotrode, 10 watts/cm3) and then the reduced viscosity product was homogenized using the same APV homogenizer. The energy consumption on the APV homogenizer was reduced by 33% and the mean emulsion droplet size was reduced/improved to a size of 0.5 microns. Viscosity reduction by the application of highly propagating ultrasonic energy as a pre-treatment improved homogenization performance with reduced energy and better more stable/smaller emulsion droplets.
Products used in the homogenisation methods include soy milk, sauces, dairy products, flavour compositions, oil water mixes, oil water hydrocolloid mixes, food products containing fats/oils, sauces, food/beverage products containing starches or hydrocolloids and beverages. Homogenising these products using the methods of the invention provides reduces energy costs, increased production rates and reduced maintenance costs, better product performance and degree of mix/emulsification.
The invention also provides a method of dispensing a liquid coating product. When a liquid coating product, such as that illustrated in
Products used in this method include vegetable oils, packaging coatings, honey and sanitisers, sugar coatings, artificial sweetner coatings, colours, chocolate coatings, coatings containing hydrocolloids. Dispensing these products using this method provides improved coating quality, greater uniformity, allows for small droplet size in coating materials when sprayed, reduced material costs, improved coating quality and improved food safety.
By way of example, baking oil coating material was sprayed using a conventional spray nozzle head giving a mean droplet size of 30 microns and required 20 g of material to coat a baking surface 15 cm×15 cm surface area. Using highly propagating ultrasonic energy to reduce viscosity (24 kHz, 10 microns amplitude, 5 seconds treatment time) of the same baking oil coating, the product was sprayed onto the cm×15 cm surface area. Mean spray droplet size was 8 microns and required only 14 g of spray coating material to achieve the same uniformity of coating.
A person skilled in the art will understand that the application of highly propagating ultrasonic energy to a liquid coating product may temporarily or permanently reduce the viscosity of the product. Accordingly, in one embodiment the outflow of the flow cell illustrated in
The present application also provides a retort cooker 78 comprising at least one highly propagating ultrasonic energy emitting assembly 34 as illustrated in
By way of example, in a laboratory based retort, three products canned tomato juice, canned pineapple juice and canned meat and vegetable soup was placed in a liquid filled retort and heated up in a retort to 140° C. The time taken to get up to temperature was 15 minutes. The same three products were pre-treated with highly propagating ultrasonic energy (24 kHz, 5 microns amplitude, highly propogating radial sonotrode for 15 seconds) reducing viscosity by 40%. The products were canned and sealed, placed in the same liquid filled retort and heated up to 140. The time taken to get to 140° C. was 9 minutes. Using highly propagating ultrasonic energy to reduce viscosity allows faster heat transfer into the three products.
Ultrasonic energy was applied to orange juice concentrate or canola oil slurry containing 20% solids. The ultrasonic energy was applied to 10 litres of each product for thirty seconds either from a conventional sonotrode, a conventional ultrasonic cleaning bath or from a highly propagating ultrasonic energy sonotrode. A 24 kHz highly propagating ultrasonic energy laboratory unit with a 10 micron amplitude highly propogating radial sonotrode, 24 kHz frequency, energy density 1 watt/cm3 was used. The conventional ultrasonic bath used was a 38 kHz Kerry Ultrasonics bath with an energy density of 0.00001 W/cm3. The conventional sonotrode used was a Branson 250 watt unit with titanium sonotrode 0.3 mm diameter and 28 kHz.
Table 1 clearly shows the increased efficacy of the ability of highly propagating ultrasonic energy to reduce viscosity of both orange juice concentrate and canola oil slurry.
Highly propagating ultrasonic energy was applied to concentrated solutions orange juice of 65° Brix (65 g sugar per 100 g solution) for 60 seconds and 120 seconds. A 24 kHz ultrasonic laboratory unit with a 10 micron amplitude highly propogating radial sonotrode, 24 kHz frequency, energy density 1 watt/cm3.
The viscosity of a control solution not exposed to highly propagating ultrasonic energy and both test solutions was measured using a Brookfield viscometer. As can be seen from
Highly propagating ultrasonic energy was applied to fresh valencia orange juice (with pulp) at 5° C. at various flow rates from 5 to 25 liters/min and the viscosity of the juice after application of the highly propagating ultrasonic energy from a 1000 watt 20 kHz highly propagating ultrasonic energy unit was used with 10 micron highly propogating radial sonotrode inserted in a stainless steel flow cell. The viscosity of the test samples of juice exposed to highly propagating ultrasonic energy and control samples of juice not exposed to highly propagating ultrasonic energy at flow rates of both 5 and 20 liters/min was also measured using a Brookfield viscometer.
As can be seen from
Highly propagating ultrasonic energy was applied to 1 Liter of each of the products set out in Tables 2 and 3 over a period of 30 seconds using a 1000 watt highly propagating ultrasonic energy unit, frequencies from 16 kHz to 24 kHz, highly propogating radial sonotrode emitting 10 microns amplitude highly propagating ultrasonic energy at an energy density of 1 watt/cm3.
The viscosity of each product was measured using a Brookfield viscometer before and after application of highly propagating ultrasonic energy and the percent reduction in viscosity calculated. The results are presented in Tables 2 and 3.
Highly propagating ultrasonic energy was applied to 1 Liter of each of the products set out in Table over a period of 30 seconds using a 1000 watt highly propagating ultrasonic energy unit, frequencies from 16 kHz to 24 kHz, highly propogating radial sonotrode emitting 10 microns amplitude highly propagating ultrasonic energy at an energy density of 1 watt/cm3. The viscosity of the same products was reduced by conventional means as indicated in Table 4.
The viscosity of each product was measured using a Brookfield viscometer before and after viscosity reduction. The results are presented in Table 4.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2008903844 | Jul 2008 | AU | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/AU09/00966 | 7/29/2009 | WO | 00 | 6/27/2011 |
| Number | Date | Country | |
|---|---|---|---|
| 60782898 | Mar 2006 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12224971 | Jan 2009 | US |
| Child | 13056645 | US |
