Continuous extraction process
AssigneeNestec S.A.
InventorJacob Gasau
Life of this patent
Estimating the term…
Abstract
A process for the continuous extraction of roasted coffee or tea, which comprises introducing dry finely ground coffee or tea at a charging station in the form of a bed with a thickness of from 0.5 to 15 cm and displacing the bed along a closed circuit up to a discharging station by way of at least one extraction station where a stream of extraction liquid is passed through the bed while a pressure gradient of the liquid on the bed is maintained.
Claims18
A process for preparing a coffee extract suitable for use in preparation of beverages comprising the steps of:
- (a) grinding roasted coffee into particles having a characteristic diameter according to Rosin, Rammler and Sperling of between about 0.25 mm and 2.0 mm;
- (b) forming a bed of the ground coffee between about 0.5 cm and about 15 cm thick;
- (c) continuously advancing said bed of ground coffee in a downstream direction past a first extraction station so that the advance of the bed carries said coffee past said first extraction station at a throughput rate of at least about 13 kg/hr;
- and
- (d) forcing a first aqueous liquid extraction medium through said bed at said first extraction station by maintaining a pressure gradient in such medium as said bed advances past such station to form a first extract, the flow rate of such medium through said bed, expressed in kg/hr, being between about 2 times and about 20 times said throughput rate,
- each portion of the coffee being extracted while in said bed for a total extraction time of between about 20 seconds and about 5 minutes.
A process for preparing a tea extract suitable for use in preparation of beverages comprising the steps of:
- (a) forming a bed of particulate tea selected from the group consisting of broken tea leaves, ground tea leaves, tea leaf dust, tea stalk fragments and combinations thereof, the tea particles having dimensions on the order of a few tenths of a millimeter, the bed being between about 0.5 cm and about 15 cm thick;
- (b) continuously advancing said bed of tea in a downstream direction past a first extraction station so that the advance of the bed carries the tea past said first extraction station at a throughput rate of at least about 5 kg/hr;
- and
- (c) forcing a first aqueous liquid extraction medium through said bed at said extraction station by maintaining a pressure gradient in such medium as said bed advances past such station to form a first extract, the flow rate of such medium through said bed, expressed in kg/hr, being between about 5 times and about 30 times said throughput rate,
- each portion of the tea being extracted while in said bed for a total extraction time of about 1 minute to about 3 minutes.
Dependencies are inferred from the claim text.