| 摘要 |
<p>1532547 Decaffeination SOC DES PRODUITS NESTLE SA 26 Nov 1976 [8 Dec 1975] 49402/76 Heading A2B Vegetable material is decaffeinated by (i) extracting with a water-immiscible liquid fatty material and (ii) separating the caffeine-laden fatty material, removing caffeine therefrom by vapourisation and recirculating the fatty material to (i). The regeneration in (ii) may be carried out at 50-450‹C, preferably 150- 250‹C, and 0.01-760 mm. Hg with a residence time of up to 4 hours, e.g. 0.3-20 minutes. The fatty material may be regenerated in film form, using falling film, wiped film or packed column techniques; such films may be up to 20 mm., preferably up to 3mm., thick. A carrier gas, e.g. steam or nitrogen, may be used to assist vapourisation. Decaffeination may take place in (i) at 0-150‹C and the fatty material may therefore be heated prior to, and cooled after, stage (ii). Although water is removed in (ii), a preliminary flash distillation of the laden fatty material is preferred. Occasional addition of fresh fatty material may be necessary; this may be treated with an adsorbent and included with the feed to stage (ii) to enable drying. 0.9-1.2% water (based on the fatty material) may be added to the regenerated fatty material prior to recirculation. The vegetable material may be solid ground or roast coffee or an aqueous extract of tea or of solid or ground coffee; solids containing 20-60% water are specified. Suitable fatty materials are safflower, soy bean, corn, peanut, coffee and olive oils, triolein and lard. Specification 1516208 is referred to.</p> |
