Clarification of fruit juices

PM seems to occur in small amounts in the vegetative tissues of all higher and lower plants investigated. It is very abundant in the tomato fruit,60 orange flavedo and albedo,21 the tobacco plant,61 eggplant62 and alfalfa it usually occurs in the commercial fungal pectinase preparations that are manufactured for the clarification of fruit juices.25 In the natural products in which the enzyme is found, the major portion of it is usually strongly adsorbed on the water-insoluble cellular components of the tissue macerates.60 62 68... 

Krystynowicz A, Bielecki S, Czaja W, Rzyska M (2000) Prog Biotechnol 17 (Food Biotechnology) 323 Application of bacterial cellulose for clarification of fruit juices... 

Pectic enzymes are used commercially in the clarification of fruit juices and wines and for aiding the disintegration of fruit pulps. By reducing the large pectin molecules into smaller units and eventually into galactur-onic acid, the compounds become water soluble and lose their suspending power also, their viscosity is reduced and the insoluble pulp particles rapidly settle out. 

Because of the solids content and the particle size of the solids, semi-closed or closed (hermetic), self-discharging plate separators are best suited for the clarification of fruit juice. 

Microcrystalline chitin has been used as a thickening/gelling agent in the binding, stabilizing, and texturing of food [58]. Chitin is widely used to immobilize enzymes and whole cells enzyme immobilization has applications in the food industry, such as clarification of fruit juices and... 

Ishii and Yokotsuka recently used pectin lyases from Aspergillus sojae 170, 171, 172) and Aspergillus japonicus (173) for the enzymatic clarification of fruit juices. This is discussed later in this review. Bush and Codner 174) compared the pectin lyases produced by Penicillium digi-tatum and Penicillium italicum and found them remarkably similar. Both were endo acting, had optimal activities at pH 5.5, and had the same K. The pectin lyase from F. italicum, however, was less stable than that of F. digitatum. Spalding and Abdul-Baki 175) reported the production of a pectin lyase by Penicillium expansum growing on apple tissue or a pectin-polypectate mixture. 

Some of the laboratory separations which may be effected and some suggestive of possible commercial separations are bacteria from water, emulsions and serums, pigment from paint, fractional separation of clay particles, clarification of fruit juices, clarification of varnishes and glues, and the separation of emulsified oils from an unemulsified portion. 

Several years ago a flotation process for clarification of fruit juices was developed in Canada [6,6a]. The juice is enzymatically treated, bentonite is added and the mixture is impregnated with an inert gas (nitrogen, carbon dioxide). Then the liquid is pumped into an especially designed flotation tank in which the solids float to the top from where they can be skimmed off in concentrated form. The liquid is polished by filtration. This process was also tested in Europe. 

Clarifying agents or flocculants are used to eliminate turbidity or suspend particles from liquids, e.g., chill haze in beer, precipitates in fruit juices and wines, and haze in oils. Often, they provide a nucleation site for suspended fines. Examples of clarifying agents are lime in sugar juice clarification, pectic enzymes to break down pectins in fruit juices, and gelatin for clarification of fruit juices. 

Pectinases, cellulases and hemicellulases are used for clarification of fruit juices, juice extraction, improvement of cloud stability of vegetable and fruit juices and nectars, liquefaction and maceration of fruits and vegetables, reduction of cooking time of pulses and improvement of rehydration characteristics of dried vegetables. The chemical basis of these treatments and of the consequential changes in sensory and nutritional quality are discussed. 

Clarification of fruit juices, e.g. apple juice depectinised juices can also be concentrated without gelling and without developing turbidity. 

These polymers are mostly applied in the paper industry for wet-strength papers usable in neutral of alkaline systems instead of the urea-formaldehyde resins requiring acid conditions for crosslinking. PolyEI increases retention of dyes, pigments and fillers. PolyEI is known as a powerful flocculant used in the clarification of fruit juices and in water treatment. It removes effectively clays, colloidal acids, pectines and tannines from water. Commercially available polyEI have molecular weights in the range Mn = 600 to 100000 60). 

Hydrolysis of pectines (pectinase) CSTR with UF membrane Production of bitterness and clarification of fruit juice and wine... 

A reactor with such a configuration was used in the clarification of fruit juice by elimination of pectin by the enzyme pectinase. The pectin, which is present in colloidal form, aggregates in the presence of the enzyme and settles, leading to easy physical clarification (Shao et al., 1989). 

Chitin was used also to immobilize enzymes and whole cells. Enzyme immobilization was used for applications in food industries such as clarification of fruit juices and processing of milk with a- and p-amylases and invertase fixed on chitin [89]. Chitin is also used for the treatment of environmental pollutants [90,91], or in biosensors [92,93]. 

Liquefaction of starch Glucose and the lique> faction of starch Production of com syrup Inversion sugar from cane sugar Clarification of fruit juices... 

Clarification of fruit juices Chitosan at low concentrations was found to be effective. Clarification of white wines The industrial tests showed that in most cases, an equivalent or even greater technological effect was obtained with chitin-glncan in comparison to common fining agents. 

Chatteijee S., 2004. Clarification of fruit juice with chitosan. Process Biochem. 39(12) 2229-2232. 

Ultrafiltration is used in many different processes at the present time. Some of these are separation of oil-water emulsions, concentration of latex particles, processing of blood and plasma, fractionation or separation of proteins, recovery of whey proteins in cheese manufacturing, removal of bacteria and other particles to sterilize wine, and clarification of fruit juices. 

Beverage Clarification of fruit juice, clarification of wine, bacteria removal, microorganism separation from fermented... 

Pectinase (polygalacturonase/ pectin esterase) Clarification of fruit juices... 

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