Method and system for entrapping pressurized gas in powdered food or beverage products
View Patent ↗Methods and systems for continuously producing foaming compositions from powders, granules, and/or particulate are provided and/or powders, granules, and/or particulates that contains high pressure gas. The methods and systems are configured to reduce energy costs and overall processing time and, thus, provide advantages over the prior batch processes that have lengthy temperature ramp-up and cool-down times due to the shortcomings of using a large pressure vessel.
1. A method of continuously manufacturing a foaming particle composition at high gas pressure, the method comprising:
adding particles to a pre-pressurization zone and increasing the gas pressure to about 20 to about 3100 psi to form pressurized particles effective to create one of passageways, cracks, or pores, and a mixture thereof in the particles;
transferring the pressurized particles to a heating zone, separate from the pre-pressurization zone, wherein the heating zone is operating at about 20 to about 3100 psi gas pressure and continuously advancing the pressurized particles, via an auger or continuous screw mechanism, along the heating zone at a rate and for a time effective to increase the temperature of the pressurized particles above the glass-transition temperature of the particles to form heated particles, wherein the auger or continuous screw mechanism agitates the particles while advancing the particles;
continuously transitioning the heated particles from the heating zone through a transition zone operating at about 20 to about 3100 psi gas pressure;
transferring the heated particles from the transition zone to a cooling zone, separate from the heating zone and the transition zone, the cooling zone operating at about 20 to about 3100 psi gas pressure and continuously advancing the heated particles through the cooling zone at a rate and for a time effective to drop the temperature of the heated particles below the glass-transition temperature of the particles to form a cooled particle;
moving the cooled particles to a de-pressurization zone, separate from the cooling zone, for dropping the gas pressure from about 20 to about 3100 psi to ambient pressure to form de-pressurized and cooled particles; and
releasing the de-pressurized and cooled particles from the de-pressurization zone to form the foaming particle composition having pressurized entrapped gas remaining therein,
wherein the pre-pressurization zone is in gas communication with the de-pressurization zone so that gas sharing occurs therebetween where gas from the de-pressurization zone is utilized to pressurize the pre-pressurization zone such that de-pressurization is synchronized with pre-pressurization.
2. The method of claim 1 , wherein transferring the pressurized particles to the heating zone exposes the pressurized particles to a thermal differential rate of about 30° C./second to about 300° C./second between the pre-pressurization zone and the heating zone.
3. The method of claim 1 , wherein transferring the heated particles from the heating zone to the cooling zone exposes the heated particles to a thermal differential rate of about −30° C./second to about −300° C./second between the heating zone and the cooling zone.
4. The method of claim 1 , wherein the transition zone between the heating zone and the cooling zone includes a free falling zone where the heated particles fall under gravity between the heating zone and the cooling zone.
5. The method of claim 1 , wherein the pre-pressurized zone is pressurized with gas from the de-pressurization zone at a rate of about 0.14 psi/second to about 725 psi/second.
6. The method of claim 1 , wherein venting of one or more of the pre-pressurization zone and the de-pressurization zone occurs over about 30 seconds to about 120 seconds.
7. The method of claim 1 , wherein the pre-pressurization zone includes air locks at an entrance and an exit thereof and an associated particle surge chamber at a gas pressure of about 20 to about 3100 psi, the particle surge chamber sized to hold a quantity of particles during pre-pressurization effective so that heating zone has a continuous supply of particles therein.
8. The method of claim 7 , wherein the air lock at the entrance to the pre-pressurization zone is configured to operate sequentially with the air lock at the exit of the pre-pressurization zone.
9. The method of claim 7 , wherein the particle surge chamber has a capacity sized to hold about a 5 minute to 15 minute residence time of particles.
10. The method of claim 7 , wherein the particle surge chamber has a capacity of about 1 to about 150 liters.
11. The method of claim 7 , wherein the de-pressurization zone includes air locks at an entrance and an exit thereof with the particle surge chamber therebetween sized to hold a quantity of particles during de-pressurization.
12. The method of claim 11 , wherein each of the air locks is a rotary valve configured to withstand gas pressures of about 20 to about 3100 psi.
13. The method of claim 11 , further comprising more than one air lock at the entrance or exit of at least one of the pre-pressurization zone and the de-pressurization zone effective to maintain continuous operation of the heating and cooling zones.
14. The method of claim 1 , further comprising a continuously operating dosing device between an exit of the pre-pressurization zone and an entrance to the heating zone.
15. The method of claim 1 , wherein a total heat input per kg of particle in the heating zone is about 200 to about 400 KJ/Kg.
16. The method of claim 1 , wherein a total energy input per kg of particle in the cooling zone is about 200 to about 350 kJ/kg.
17. The method of claim 1 , wherein the residence time in the heating zone is about 1 to about 40 minutes.
18. The method of claim 1 , wherein a ratio of the residence time in the heating zone to the cooling zone is about 0.2 to about 13.
19. The method of claim 1 , wherein a maximum gas entrapment is obtained with a residence time in the heating zone from about 15 to about 30 minutes at temperatures of about 120° C. or less.