Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Juices cloudy concentrates

It is common to produce natural cloudy juices and concentrates as standard products from specific fruit varieties such as citrus, exotic fruit and also from apple, pear and berries. Freshly squeezed juices can be bottled as such. The juice is heated (85° -90°C) and hotfilled into clean bottles. The bottles are closed and then immediately cooled with water as quickly as possible to avoid deterioration of the juice due to the high temperature. The high filling temperature sterilises bottles and product. [Pg.171]

Next to the natural cloudy juices it is also customary to produce clear juices and concentrates, specifically from apple, pear and berries. For this purpose the juice must be clarified which can be achieved by the following three different processing methods ... [Pg.171]

Low juice content is defined by a content of 1 to 20% by weight of juice in the final drink. These products are mainly based on citrus juices. As mentioned before, citms juices provide good turbidity and stability even with low juice content. In combination with special raw materials made from citrus, like cloudy concentrates or peel oils, very stable low-juice drinks can be obtained. Turbidity comes from a complex mixture of dispersions of fruit cells and oil-in-water emulsions, stabilised by fruit pulp particles and hydrocolloid stabilisers, such as locust bean gum [9]. [Pg.470]

In the extraction of citms juices it is desirable to have as gende an extraction pressure as possible. There should be minimal contact time between juice and pulp to reduce the amount of bitter substances expressed from the peel into the juice. The amount of suspended soHds in citms juice is controlled in a subsequent separation in a finisher. A screw action is used to force the juice through a perforated screen and separate the larger pulp particles from the juice. The oil level in the juice is adjusted by vaporizing under a vacuum (10). The separated pulp is washed and finished several times to produce a solution which is then either added back to the juice to increase juice yield, or concentrated to produce pulp wash soHds, also called water extract of orange soHds, which can be used as a cloudy beverage base. [Pg.571]

About 40 millions tons of apples are gathered per year and about 10% are processed mostly to produce clear concentrate but a little part as cloudy juice. The aim of pectinases application is to increase the plants productivity by processing apples quantity as high as possible along the season with high yields (see Table 2). [Pg.454]

The pineapple fruit is mainly processed for canning as slices or cubes. After cutting, the residual pulp is removed from the peel for cloudy juice production. Then, by-products are used to produce clear juice for slices cover or as clear concentrate. In the process of clear juice, by-products are crushed and pressed. The juice is pasteurized, cooled down and depectinized with enzymes at 50°C before ultra-filtration and concentration... [Pg.460]

Pulp from ripe Golden apple was pressed in a mortar and filtered, thus obtaining a cloudy and dense juice. Potassium metabisulphite was added as antioxidant at a final concentration of 0.15 mg/mL. The pH of the prepared apple juices was 4.1 4.3. Depectinisation experiments were carried out loading the juice in the packed bed reactor and recycling for 30 min at 25 "C. The reaction mixture was then collected and the percentage reduction of viscosity measured as above described. The y-alumina spheres were abundantly washed with distilled water before performing the successive batch reaction. [Pg.974]

If juice is to be sold as not from concentrate it is usually screened and pasteurised immediately after pressing - an operation with two main objectives. The first is to control the growth of spoilage micro-organisms that live on the fruit surface (mainly yeasts and moulds). The second is to destroy the pectolytic enzymes that occur naturally in fruit that would otherwise break down the cloudy nature of the juice. If, however, a clear juice is required (e.g. apple or raspberry), enzymes can be added to accelerate this natural process. [Pg.9]

When the final juice product is a concentrate, the clear filtered or cleaned cloudy juices are automatically subjected to heat treatment during the course of their concentration. (Figure 3.7 provides on overview of the concentration process.) Heat treatment of juices is an area where the design of process requires careful consideration in order to avoid any detrimental effects on flavour and appearance of the product. Early evaporators had demonstrated that high-vacuum-low-temperature processing produced concentrate of good flavour quality, but it was soon discovered that there was a drawback in that the heat treatment was insufficient to deactivate pectin methylesterase, which gave rise... [Pg.52]

Concentrated juices. It will be evident from the section on nomenclature that the principal fruit components that are used in dilutable soft drinks are fruit juices (both clear and cloudy) and whole fruit preparations - the so-called comminutes. [Pg.131]

Improve yield of press juices, prevent cloudiness, improve concentration processes Extraction of oil Clarification... [Pg.283]

On an industrial scale, today juice concentrates are virtually only produced by evaporation. There are some new developments which are technically highly interesting but of which only a few commercial installations are in operation (see below). Cloudy juices should be depulped before evaporation. This can be achieved by centrifugation using automatically de-sludging centrifuges. [Pg.174]

Effect of Cationic Resin (CR) Treatment on the pH, Ion Concentration, and Ionic Strength (/) of Cloudy Apple Juice (CAJ)... [Pg.293]

Pulp-Serum Separation. As for freeze concentration, high viscosity contributes to limiting the degree of concentration which can be achieved by membrane concentration. Since the insoluble solids present in citrus juices contribute significantly to viscosity, one consideration for process development is to separate the pulp from the clear serum, prior to concentration. Because consumers recognize that citrus juices are cloudy and contain pulpy material, it becomes a requirement to blend the separated pulp back with the product concentrate (31). [Pg.301]

Apple polyphenols are present in different parts of the fruit. A major source is the skin, which contains all the flavonols and anthocyanins in addition to an important amount of dihydrochalcones. ° Phenolic acids are present in the flesh whereas most of the dihydrochalcones are in the core and the seeds. This distribution in different parts of the fruit also affects polyphenol concentration of apple juice where only small amounts of quercetin glycosides and dihydrochalcones are present. However, polyphenol content is also affected by the technological procedure. The oxidative conditions and the clarification process during the production of clear apple juice reduces the phenolic content. In contrast, the anaerobic conditions and the lack of a clarification step during cloudy apple juice production prevents an important loss of polyphenols. ... [Pg.176]

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. [Pg.258]


See other pages where Juices cloudy concentrates is mentioned: [Pg.374]    [Pg.458]    [Pg.374]    [Pg.374]    [Pg.169]    [Pg.458]    [Pg.64]    [Pg.122]    [Pg.606]    [Pg.606]    [Pg.1166]    [Pg.171]    [Pg.182]    [Pg.255]    [Pg.238]    [Pg.230]    [Pg.76]    [Pg.183]    [Pg.187]   
See also in sourсe #XX -- [ Pg.470 ]




SEARCH



Cloudiness

Cloudy concentrates

Juice concentrate

Juices cloudy

© 2024 chempedia.info