Vef-etables should "be cooled as rapidly as tjossiole after scalding 

 to minimize the effect of heat upon the flavor. Cooling is ordinarily ' 

 accom-olished hy immersion in largo quantities of frosh, cold v>^ater. 

 Fot more than a few minutes should elapse "between scalding and freez- 

 ing, or the quality may he impaired. 



FR3EZi:Ta MD STORII^G ; 



products may he frozen -orior to T»ackaging, or in the -oackages 

 intended for distrihution. In freezing prior to packagin-r, products 

 may he exposed in shallow l?y37's on helts or trays to the freezing 

 action of som.e liquid or gas, cooled and circulated at lo'-/ temperature. 

 Q-ases used include air, carton dioxide, and hrine fog; liquids include 

 orine and sugar syrut). Several continuous processt -^ ha.-'-e heen develop- 

 ed and are extensively a"Dplied. In some inrtance? the freezing of small 

 Droducts such as English peas may he suhstantially com-nleted within a few 

 m.inutes. Ice cream freezers have heen used for freezing juices and pulrts 

 prior to packaging. 



'/.Hien products are frozen in uackages, ra-oid freezing depends 

 upon adequate contact of packages '-ith some medi\im of high heat con- 

 ductance which is m.aintained at a suitably low temperature. Metallic 

 Tolates, solid carhon dioxide, and rabidly circulated air are used as 

 heat exchange media for freezing products in cartons, oarrels, and 

 crates. In addition, alcohol and hrines are used for freezing r)ro- 

 ducts in sealed containers. Cans may he rotated, as in canning, to in- 

 crease the rate of heat transfer as much as 40C -oercent. 



TemToeratures used for freezing range from 0° to -90° F. A 

 temperature of ahout -18° F, is commonly maintained in air circulated 

 rapidly over ammonia expansion coils, for freezing hulk products on 

 trays or on helt conveyors prior to packaging. 



Som.etimes a fine spray of cold water, or weaic orine, is applied 

 to veeetahles hefore leaving the freezing tunnel, to urovide a contin- 

 uous transparent glaze of ice, enhancing the ap-oearance and providing 

 some "orotection from contact with the air. Allowance for the '"eight 

 of tho ice shov.ld he made in declarations of the net contents of the 

 package. 



In general, the rate of freezing is more imT3ortant than the 

 temperatr.re employed, and is im-oortant for iriost pr-'icts. Berries, 

 frozen with sugar in harrels in the "cold -oack" -oro^ess, were suitable 

 for use hy preserve and ^^elly manufacturers. It was only considered 

 necessarjT- to freeze the product with sufficient ranidity to avoid 

 fermentation. The shrinkage and fi-^iing of herries h"- the syrun was 

 welcomed. 



Quick freezing is desirable for many fruit and vegetable "oroducts, 

 to avoid changes prior to freezing and to m.inimij'e dajiiage to texture by 

 the freezing process itself. Damage to texture may result if slowly formed, 

 largo crystals of ice rupture cells. Slow freezing may also effect 



