METHOD AND APPARATUS FOR PASTEURIZATION OF BEVERAGES

摘要

This application relates to a precision tunnel pasteurization process in which the spray density is above about 285.19 l./min./m<2> (7 gal./min./ft.<2>) of processing area and the spray is uniformly distributed over the processing area of the pasteurizer whereby the spray water heats the beer to 60-61.66 DEG C (140 - 143 DEG F) and then cools the beer to 21.11-29.44 DEG C (70 - 85 DEG F). The spray nozzles are positioned on staggered centers having 22.86-30.48 cm. (9 - 12 inch) longitudinal spacing and 15.24 cm. (6 inch) transverse spacing with 7.62 cm. (3 inch) spacing from side walls and the nozzle bore is 0.95 cm (3/8 inch). The nozzle pressure is about 0.352-0.422 kg./cm<2> (5 psig to 6 psig) and the spray nozzles are the type which are the least likely to become clogged. The overlapping hollow cone sprays produce a very uniform spray density at the elevation of the top of the cans or bottles. …The improved pasteurizer also has the first heating zone regenerative with the first cooling zone. The advantages of this arrangement are particularly significant on a double deck pasteurizer with sprays only above the top deck. The spray temperature of the lower deck of the first cooling zone is higher than that supplied to the upper deck. The final result is to minimize the total accumulated P.U. difference between decks to less than 3 P.U. This uniformity in P.U. between decks is possible with product temperatures on the lower deck in slight excess of the required 60 DEG C (140 DEG F) minimum peak product temperature.