Powdered products from fruit and vegetable juices aqs - vegetable extracts such as coffee, tea, etc having porous

摘要

Powdered products from fruit and vegetable juices aqs vegetable extracts such as coffee, tea, etc having porous light texture and deep colour. Are prepared by super-cooling, completely or partially, the aq. soln. first by direct contact with cooling surfaces or with refrigerants at a temp. below the eutectic f.pt. of the soln., to obtain a clear ice. This is then carefully partially thawed, to a degree of freezing of less than 50% to temps. above the eutectic f.pt. The ice is then allowed to stand, its texture modifying because of the growth of the non-frozen droplets of liquid, and a mixt. of ice and deep-coloured liquid is obtained. This mixt. is then slowly and completely super-cooled such that the deep colouration remains unchanged and the ice is then dried in known manner. If the juice or aqs. extract is foamed with a gas during the supercooling, e.g. as in ice cream making machines, a porous ice is obtained and consequently dry powder of low apparent density.