Sara Lee/DE N.V. was awarded US patent 6183800 February 6 for a new use of an old device: using venturi for agitating concentrates of coffee/milk. The invention is titled “Method for preparing frothed milk or cafe creme.”
Besides Sara Lee, others active in this field are Spidem S.r.l., Caffe Acorto, Nuova Faema S.p.A., Arthur Eugster AG, Conair, Societe Agricole de Produits de Base and Bunn-O-Matic. One notable absentee is Nestlé.
Abstract:
According to the method for preparing frothed milk or cafe creme, milk concentrate or coffee concentrate is mixed with water, using a venturi chamber. The venturi chamber comprises a water inlet, a concentrate inlet and an outlet. Further, a whirl chamber, located downstream of the venturi chamber, is used, which is in fluid communication with the outlet. The water is supplied under pressure via the water inlet to the venturi chamber, so that a reduced pressure is created in the venturi chamber. The concentrate inlet is brought into fluid communication with a stock of milk or coffee concentrate, so that, as a result of the reduced pressure in the venturi chamber, via the concentrate inlet, milk or coffee concentrate is sucked into the venturi chamber. The milk or coffee concentrate and the water then flow together via the outlet to the whirl chamber, and the milk or coffee concentrate and the water are beaten in the whirl chamber to form frothed milk or cafe creme.
First of 21 Claims:

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By GlobalDataA method for preparing cafe cream, comprising the steps of mixing coffee concentrate with hot liquid water, creating a reduced pressure in a venturi chamber having a water inlet, a concentrate inlet and an outlet, and using a whirl chamber located downstream of the venturi chamber in fluid communication with the outlet, by supplying the hot liquid water under pressure via the water inlet to the venturi chamber, bringing the concentrate inlet into fluid communication with a coffee concentrate, and as a result of the reduced pressure in the venturi chamber, drawing the coffee concentrate into the venturi chamber, flowing the coffee concentrate and the hot liquid water together via the outlet to the whirl chamber.
By Navroz Havewala, just-food.com correspondent