Juice removal

Several types of Brown extractors are used in the citrus industry throughout the world. The Model 400 produces a juice that is low in peel oil content and high in juice quality. The fruit is halved and the juice removed by a rotating reamer that exerts pressure to effect extraction. 

Must and Wine Yield. The wine gallon yield per ton varies with type of grape, whether white or black. Total wine gallon yield is composed of three fractions. The main volume is the free-run juice that flows from the crushed grape second is the drain screen juice that separates from the pomace, which already has had the free-run juice removed and third is the press juice from the tight squeezing of the screen-drained pomace that was conveyed to the grape press. 

Food beverage—recovery of proteins for milk and whey, sugar concentration of fruit juice, removal of bacteria and suspended solids and organics from bottled drinking water,... 

Procedure. Simply strain the juice ) in soft juicy fruits such as tomatoes, currants, gooseberries, raspberries, strawberries, melons and citrus fruits through a hydrophilic gauze into a 25-ml. beaker. Deoxygenate 5 ml. of 1 M acetate pH 4-7 buffer in a Kalousek vessel and add 5 ml. of the juice. Remove the rest of the oxygen and record the anodic wave of ascorbic acid. 

In North America, there has been a surgical bias that antireflux surgery should be undertaken much more frequently to prevent the development of adenocarcinoma in patients with Barrett s esophagus. The rationale proposed claims that the prevention of the exposure of the metaplastic esophageal mucosa not only to acid but also to bile salts and other constituents of the gastric juice removes the inciting agents (sic) for this disease. Unfortunately, the primary hypothesis is flawed by the lack of evidence that the... 

Soybean products that have been processed to remove a portion or all of the carbohydrates and minerals are used to make textured vegetable proteins which can be formed into various shapes and textures (see Soybean and other oilseeds). Many canned dog foods utilize the textured vegetable protein chunks with added juices, flavor enhancers, vitainins, and minerals to produce canned dog foods that have the appearance of meat chunks. 

The Vepex process developed in Hungary (Table 9) involves disintegration of plant materials followed by double screw pressing to maximize juice production. Green chloroplastic protein is removed by direct steam-injection heat treatment at 82°C with the addition of flocculents and centrifugation. The white protein fraction is separated from the chlorophyU-free process juice by direct steam injection at 80°C, followed by centrifugation and drying (94). 

In another extractor (Automatic Machinery and Electronics Inc. (AMC)) the individual fmits are cut in half as they pass a stationary knife. The halves are oriented in a vertical plane, picked up by synthetic mbber cups, and positioned across plastic serrated reamers revolving in a synchronized carrier in a vertical plane. As the fmit halves progress around the extractor turntable, the rotating reamers exert increasing pressure and express the juice. The oil and pulp contents in the juice increase with greater reaming pressure. The recoverable oil is removed in a separate step prior to juice extraction. Needle-sharp spikes prick the peel of the whole fmit, releasing oil that is washed away with water and recovered from the oil—water emulsion. 

A rack and frame press uses heavy nylon cloth positioned in a wooden frame inside a rack. A measured amount of apple or other fmit mash is added from a hopper above the frame. The mash is leveled with a hand trowel and the edges of the nylon cloth are folded over the mash to encase it and create a cheese. The frame is removed, and a second rack is placed on top of the first cheese the process is repeated until a stack of cheeses is prepared. A hydrauhc ram then appHes gradually increa sing pressure on the stack and expresses the juice. A high yield of juice (80%) is obtained and no press aid is required. Because this process is labor intensive (17), it is mostly used for small farm and pilot-plant operations. 

The Bucher-Guyer horizontal rotary press is a highly automated batch process machine that requires no press aid. The press consists of a horizontal hydrauhc ram inside a rotating cylinder containing many flexible rods covered with a knitted synthetic fabric. The rods have serrated surfaces to allow juice which passes through the fabric to flow to the discharge ends. Hydrauhc pressure is apphed for a preset time, the ram is retracted, and the cylinder is rotated to break up the press cake. This cycle is repeated several times before the press cake is removed from the cylinder and the press is cleaned (16). Juice yield for this horizontal rotary press is 84% with secondary water addition it is increased to 92% (15). 

There are two methods available for aroma recovery. In one method, a portion of the water is stripped from the juice prior to concentration and fractionally distilled to recover a concentrated aqueous essence solution. Apple juice requires 10% water removal, peach 40%, and Concord grape 25—30% to remove volatile flavor as an essence. Fractional distillation affords an aqueous essence flavor solution of 100—200-fold strength, which means the essence is 100 to 200 times more concentrated in flavor than the starting juice. A second method of essence recovery is to condensate the volatiles from the last effect of the evaporator they are enriched in volatile flavor components (18). 

Use of ultrafiltration (UF) membranes is becoming increasingly popular for clarification of apple juice. AH particulate matter and cloud is removed, but enzymes pass through the membrane as part of the clarified juice. Thus pasteurization before UF treatment to inactivate enzymes prevents haze formation from enzymatic activity. Retention of flavor volatiles is lower than that using a rack-and-frame press, but higher than that using rotary vacuum precoat-filtration (21). 

Evaporation and Distillation. Steam is used to supply heat to most evaporation (qv) and distillation (qv) processes, such as ia sugar-juice processiag and alcohol distillation. In evaporation, pure solvent is removed and a low volatiUty solute is concentrated. Distillation transfers lower boiling components from the Hquid to the vapor phase. The vapors are then condensed to recover the desired components. In steam distillation, the steam is admitted iato direct coatact with the solutioa to be evaporated and the flow of steam to the condenser is used to transport distillates of low volatiHty. In evaporation of concentrated solutions, there may be substantial boiling poiat elevation. For example, the boiling poiat of an 80% NaOH solution at atmospheric pressure is 226°C. 

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