Juices cloudy

Identify the following as an element, compound, homogeneous mixture, or heterogeneous mixture hydrogen, polyethylene plastic, clear apple juice, cloudy apple cider, syrup, paint, and bronze. 

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. 

Nitrite is usuaUy one indicator of the infection level in the diffuser. Exposure of nitrite to sulfur dioxide, either as a diffusion additive or later to thin juice, results in the production of potassium imidodisulfonate which precipitates when sugar is later crystallized, a cause of turbid or cloudy sugar. 

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). 

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... 

Several combinations of pectinolytic and cellulytic enzymes were tested for their ability to give a cloudy apple juice of Belle de Boskoop apples. Selected results are shown in table I. 

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. 

The immobilised Pectolyase Y-23 was used to perform consecutive depectinisations of a cloudy apple juice in batch reactions. After five reaction cycles, the percentage reduction of viscosity was greater than 90%. The viscosity of the apple juice feed through a bed of inactive y-alumina spheres remains unchanged thus confirming that the viscosity loss attributable to pectin adsorption on the carrier is negligible. The alcohol tests, performed on the juices previously treated with the... 

The pectinase was supported on y-alumina and the three enzymes present in the pectinase sample were found still active after the immobilisation. The supported biocatalyst was used in several reaction cycles to perform consecutive depectinisations of a cloudy apple juice with a negligible loss of biocatalytic activity. 

Ozoglu H and Bayindirli A. 2004. Inhibition of enzymatic browning in cloudy apple juice with selected antibrowning agents. Food Control 13 213-221. 

Sweet orange oil is obtained from the peel of the fruits of Citrus sinensis (L.) Osbeck. It is a yellow to reddish-yellow liquid with the characteristic odor of orange peel and may become cloudy when chilled. Sweet orange oil is often produced in combination with orange juice (e.g., in the United States, Brazil, Israel, and Italy). 

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. 

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... 

Carrier for oil-based flavours or colours. Gives cloudy effect in drink to replace or enhance cloud from natural juices... 

Despite the removal of compositional legislation, the descriptions of dilutable soft drinks in the United Kingdom are still widely used today. Consumers and enforcement authorities alike still have an expectation that a product described as a squash will be a cloudy product containing a significant proportion of fruit juice. Similar expectations still apply to the other products mentioned above. 

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. 

Lemon Frozen juice or sulphite-preserved 4 1 or 5 1 clear or cloudy product 25 t0°Brix (4 1-6 1)... 

Liquid extracts such as infusions will often, over time, produce a fine sediment. There may be a statement to this effect in the specification and on the container label. If the product for which the extract is destined is a cloudy drink or opaque like a fruit juice, then the container can be shaken each time to re-disperse the sediment before weighing out. If it is essential for the extract to be clear, then it must be carefully decanted when weighing out for a production batch. Extracts in storage will often change colour over time. Thus, specifying a colour parameter without a time factor can lead to the situation where a customer s QC accepts the extract on delivery, as it meets colour standards at the time, but rejects it on retesting later after it has spent some time in the raw materials store -particularly if the drum has been opened and is part used. 

Qin, L., Xu, S., and Zhang, W. 2005. Effect of enzymatic hydrolysis on the yield of cloudy carrot juice and the effects of hydrocolloids on color and cloud stability during ambient storage. J. Sci. Food... 

FIG. 18 Schematic layout of a two-compartment configuration using bipolar (bmp) and anionic (a) membranes proposed to inhibit enzymatic browning of cloudy apple juice (Tronc et al., 1998) via preliminary acidification to pH 2.0 and subsequent de-acidification to pH 3.5 by reverting flow of HCl and apple juice streams. 

Quoc, A.L., Lamarche, F., and Makhlouf, J. 2000. Acceleration of pH variation in cloudy apple juice using electrodialysis with bipolar membranes. J. Agric. Food Chem. 48, 2160-2166. 

Chitin consists of chains of cyclic carbohydrate molecules linked together and it is basically the same as cellulose except that in place of a hydroxy group (OH) on the rings there is an acetylamino group (NHCOCHj). Like cellulose, chitin is insoluble in water. Removal of the acetyl part to leave the amino group produces a modified chitin which can be used to remove the cloudiness of beers and fruit juices. 

Liquefaction clear and cloudy juices (fruits + berries, tropical fruit, vegetables Cell wall destruction for isolation of interesting cell constituents Liquefaction and saccarification of biomass... 

Improve yield of press juices, prevent cloudiness, improve concentration processes Extraction of oil Clarification... 

To maintain cloud stability in fruit juices, high-temperature-short-time (HTST) pasteurization is used to deactivate pectolytic enzymes. Pectin is a protective colloid that helps to keep insoluble particles in suspension. Cloudiness is required in commercial products to provide a desirable appearance. The destruction of the high levels of pectin-esterase during the production of tomato juice and puree is of vital importance. The pectinesterase will act quite rapidly once the tomato is broken. In the so-called hot-break method, the tomatoes are broken up at high temperature so that the pectic enzymes are destroyed instantaneously. 

This behaviour ean be quahtatively explained by Equation (12.7) since 4>m increases as the width of the size distribution increases. A good example of the ef-feets that particles and polymers have on the rheological behavior of liquids is cloudy apple juice (Genovese and Lozano, 2000). The aqueous milieu of the juice is a solution of sugar, acids and salts (i.e., the clarified juice) that contains charged particles (0.25-5 pm in size) and pectin as a colloidal dispersion. The viscosity of cloudy apple juice has been described by the expression ... 

Genovese, D.B., and Lozano, J.E. (2000). Effect of cloud particle characteristics on the viscosity of cloudy apple juice. J. FoodSci. 65, 641-645. 

In the fruit juice industry, separators are used primarily for removal of suspended solids. In the separator cloudy juice is subjected to a high centrifugal force, thus separating the solids from the liquid. 

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