Fruit juicing processes

Figure 3 Size fractionation of EDTA-soluble polyuronides from Rutgers and transgenic fruit juice processed by cold- and hot-break methods. Pectin from processed juice was extracted as ethanol-insoluble solids and size fractionated on a Sepharose CL4B column. Under the same chromatographic conditions, elution of the branched dextrans with average molecular mass 2000, 500, 252, 151, 40 and 17.7 kD-peaked in fraction number 46, 50, 54, 62, 67 and 72, respectively. Modified from Thakur et al. [23].

In this presentation, we will take examples of different fruit juice processes and will try to relate enzyme activities, the role they play and the transformation they occur in terms of finished products. These examples will concern apple juice, french cider, pineapple and wine. 

Fruit juices processing may seriously affect flavanol content. For example, the preparation of commercial apple juice decreased the flavanol content in a stepwise manner. In particular, crushing and pressing, storage of the concentrated juice at room temperature and decolorization by treatment with activated carbon destroy the flavanols almost entirely [46]. 

Nagy, S., Chen, C.S., and Shaw, P.E. 1993. Fruit Juice Processing Technology. AgScience, Aubumdale, Fla. 

On a global scale, there is good correlation between quality standards for fin it and fruit juice processed in different regions. In the European Union, legislative controls are set up, or modified, by the central European Council of Ministers, usually following discussion with and between trade organisations from the EU member countries. A new directive, once agreed and approved, is translated into the statutory laws of the member countries concerned. 

An inexpensive oil which may have been produced by a variety of methods. An inferior qualitf essential oil is produced in large quantities from the by-products of fruit juicing processes. 

Pectinex Ultra SP-L is a commercial enzyme preparation from Aspergillus acu-leatus that is used in the food industry for reducing viscosity in fruit juice processing. It contains different pectinolytic and cellulolytic enzymes [29]. In addition, the existence of fructosyltransferase activity in Pectinex Ultra SP-L has been reported by several authors [30-32]. In recent years, we have investigated the purification, characterization, and application of the fructosyltransferase from A. aadeatus contained in this commercial preparation [33]. 

Enzymes find commercial use in detergents, leather processing, baking, brewing, cheese mannfactnre, fruit juice processing, dairy production, animal feed, wine making and textiles. A wide variety of different enzymes finds use in textile areas as shown in Table 17.1. This chapter will focns on cellulases, which are enzymes that catalyse the hydrolysis of the cellnlose polymer. Except for the peroxidases, which are used to improve colour fastness and are described in Chapter 13, all the other types of enzymes are nsed for preparation processes and therefore not inclnded in this discussion. 

Wrolstad, R.E., Wightman, J.D., and Durst, R.W. 1994. Glycosidase activity of enzyme preparations used in fruit juice processing. Food Technol. 48(11) 90, 92-94, 96, 98. 

Bates, Morris, CrandaU, Principles and practices of small- and medium-scale fruit juice processing. FAO Agricultural Service Bulletin 146 (2001)... 

In order to offer the consumer a greater variety of dairy products other then milk, UHT milk, sour milk products, cream, butter or cheese, the dairy industry has developed a variety of flavoured dairy products and later in the sixties, dairy products containing (fruit) preparations. The latter category originated from a close cooperation between the dairy industry, fruit manufacturers and flavour houses. Fruit juice processing companies, marmalade manufacturers and also flavour houses established departments for (fruit) preparations which resulted in a great variety of preparations. 

Beer, wine, and dough fermentation, cheese production, milk and fruit juice processing... 

Acids such as citric and malic are permitted for use in pH adjustment in fruit juice processing which may confound the inter-... 

Uses Foam control agent tor food processing, fruit juice processing, paper coatings, pesticides, herbicides, fertilizers, industrial detergents, cosmetic cleansers Features Food grade... 

Amylase and pectinase Polysulfone single-hollow-fiber unit BMR Fruit juice processing 35... 

Commercial pectinase Hollow-fiber ultrafiltration unit BMR Fruit juice processing 34... 

The low surface tension of silicone oils have allowed their use as antifoam agents in various applications such as textile dyeing, fermentation, fruit juice processing, antacid tablets and so on. 

Fruit juice processing is a major use for membrane filters, particularly for clarification (using microfiltration or ultrafiltration), concentration (using reverse osmosis) and deacidification (using electrodialysis). The clarification of apple juice by ultrafiltration is now an important process, whether making clear juice or natural (i.e. cloudy) ones. 

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