The crushed apple juice is produced, without the aid of a cider press, by 1478_C18.fm Page 463 Thursday, July 15, 2004 10:01 AM Copyright 2005 by CRC Press LLC 464 Processing Fruits: Science and Technology, Second Edition passing coarsely ground apples through a pulper and desecrator before pasteurization. Frozen apple juice concentrate can be either natural or clarified juice concentrated to 42∞ Brix, packaged and quick frozen. Commercial apple juice concentrate is normally the clarified apple juice that has been concentrated to 70∞ Brix or higher, evaporating much of the water. Most commercial cultivars of apples will produce an acceptable juice, particularly when blended.
The character of the apple juice is directly related to the cultivar and maturity of the apple used to make the product. Juices produced in the eastern U.S. are more acid than those juices produced in the west (Downing, 1989). This flavor difference is directly related to the cultivars predominantly grown in these areas. In both eastern and western juice manufacturing facilities, the juice product is usually a blend of the juice from two or more cultivars. This blending procedure allows for a more uniform product throughout the season and from season to season. Regardless of the cultivar, only sound, ripe fruit showing no decay should be used. “Wind falls” or apples picked up from the ground should not be used for juice due to the pronounced “musty” or “earthy” flavor the apples pick up. Immature apples produce a juice lacking in flavor and very “starchy” and astringent. Over-mature apples are very difficult to press, clarify, and filter.
Figure 18.5 illustrates the process typically used for making apple juice and concentrate. Apples for juice are dumped, either by the bulk truck load or pallet bins, into a water filled receiving tank. In this tank the apples are soaked to remove soil and other foreign material. The raw fruit is then conveyed from the water to be inspected, and any damaged or decayed fruit removed or trimmed. In recent years there has been concern for the presence of over 50 ppb of patulin in the finished juice.
Patulin is a micotoxin produced by the mold Penicillium expansium, found in “bulls eye” rot of apples. Although this micotoxin is easily destroyed by oxidation, the concern of patulin is an indicator to determine if the juice was produced from mistreated or spoiled apples. Some manu[1]facturers rely on brush scrubbers to remove any decayed areas on the fruit to eliminate patulin producing mold spots from the apples. Sorting and trimming of apples to remove damage or decayed fruit is mandatory. If not removed, damaged or decayed fruit may also impart off-flavors to the finished product and increase the risk of microbiological contamination. Before pressing, whole apples are ground into a mash or pulp for extraction.
This mashing process is accomplished with either a disintegrator, hammer, or grating mill. These mills crush or cut the apple to proper consistency, depending on the maturity of fruit. When milling firm fruit for juice, small particles are desired. As the season progresses and the apples become softer, pressing becomes more difficult, thus bigger particles of pulp are preferred for pressing. Equipment used to extract juice from apples is of several types and many variations (Nelson and Tresler, 1980). The pressing process can be batch or continuous, depending upon the type of press used. More common types of presses apply pressure via hydraulic, pneumatic, screw, basket, or traveling belt methods.
Apple varieties: EarlyWorcester.htm . HowgateWonder.htm . JamesGrieve.htm . OrleansReinette.htm . RibstonPippin.htm