Liquid pectin

Pectin is widely distributed in plants. It is produced commercially from peels of citrus fruits and from apple pomace (crushed and pressed residue). It is 20-40% of the dry matter content in citrus fruit peel and 10-20% in apple pomace. Extraction is achieved at pH 1.5-3 at 60-100 °C. The process is carefully controlled to avoid hydrolysis of glycosidic and ester linkages. The extract is concentrated to a liquid pectin product or is dried by spray- or drum-drying into a powered product. Purified preparations are obtained by precipitation of pectin with ions which form insoluble pectin salts (e. g. AI +), followed by washing with acidified alcohol to remove the added ions, or by alcoholic precipitation using isopropanol and ethanol. 

The pectin of commerce is an off-white colored powder which is soluble in hot water to the extent of 2-3%. Some pectin is also sold in the form of concentrates ( liquid pectin ). The major use for manufactured pectins is... 

The following are some of the typical industrial applications for liquid-phase carbon adsorption. Generally liquid-phase carbon adsorbents are used to decolorize or purify liquids, solutions, and liquefiable materials such as waxes. Specific industrial applications include the decolorization of sugar syrups the removal of sulfurous, phenolic, and hydrocarbon contaminants from wastewater the purification of various aqueous solutions of acids, alkalies, amines, glycols, salts, gelatin, vinegar, fruit juices, pectin, glycerol, and alcoholic spirits dechlorination the removal of... 

In case of copper some rheological experiments carried out at a given polymer concentration and increasing amoimt of cations indicates that copper/pectin systems in the one-phase domain behave as a viscoelastic liquid rather than a viscoelastic solid referred to as true gel (G (co) = G, when to—>0 with Gg the equilibrium shear modulus)[35]. Despite the lack of experimental data the range in cation and polymer concentration in which true gels may be observed seemed very limited. These results corroborate the strength of the binding of copper by pectins evidenced by the properties of the phase separation curves. 

Among the five different species of Azospirillurn, only A. irakeme shows clearly pectinolytic activity on solid and in liquid medium. Moreover, this species can grow under non-diazotrophic as well as diazotrophic conditions when pectin is the sole carbon source (Khammas and Kaiser, 1991). Khammas and Kaiser (1991) analysed the pectinolytic activity of seven A. irakense isolates, and gave evidence for the presence of two types of pectinolytic enzymes. All strains tested have inducible Ca dependent pectate lyase activity. Six strains, showed also pectin methylesterase activity. So far, none of the corresponding enzymes have been purified. 

Most pectin solutions behave like Newtonian liquids below a pectin concentration of about 1 % (w/w). Onogi (1966) derived the critical concentration of polymer solutions from plotting the double logarithmic curves of viscosity (ii) against concentration at constant shear rates. Each curve consists of two straight lines intersecting at the critical concentration. At higher... 

Visco-elastic fluids like pectin gels, behave like elastic solids and viscous liquids, and can only be clearly characterized by means of an oscillation test. In these tests the substance of interest is subjected to a harmonically oscillating shear deformation. This deformation y is given by a sine function, [ y = Yo sin ( t) ] by yo the deformation amplitude, and the angular velocity. The response of the system is an oscillating shear stress x with the same angular velocity . 

One of the important criteria taken into account for the choice of an industrial producer strain is its ability to secrete enzymes on cheap and local substrate. Thus, we cultured our mutant as well as the Pol6 mutant on a local substrate milled "orange peel", at the same concentration as citrus pectin in the liquid medium. The results summarized on table 3 show a net difference between both strains the CTl mutant is able to produce high amounts of endo and exopectinases on both substrates whereas Pol6 is unable to hyper-produce both pectinases on "orange peel". 

During a study of the biosynthesis of pectin substances, a sensitive micromethod for the assay of pectinesterase activity was developed111 that uses a biosynthetically prepared [14C] methyl-labelled pectin as the substrate after enzymic de-esterification, the substrate remaining is precipitated with an excess of methanol and, after centrifugation, the [14C]methanol present in the supernatant liquor is counted in a liquid scintillation counter in order to assess the pectinesterase activity. 

The particulate fraction, called potato pulp, besides the fruit liquid and water in intact cells, contains starch, cellulose, hemicelluloses, pectin, and proteins. On a dry matter basis, the pulp contains 74% of protein in comparison to the content in potato tuber (Kempf, 1980). Components of conventional wet potato pulp are listed in Table 16.1. 

Kaolin is a naturally occurring hydrated magnesium aluminum silicate (attapulgite), and pectin is an indigestible carbohydrate derived from apples. Both appear to act as absorbents of bacterial toxins and fluid, thereby decreasing stool liquidity and number. They may be useful in acute diarrhea but are seldom used on a chronic basis. A common nonprescription preparation is Kaopectate. The usual dosage is 1.2-1.5 g after each loose bowel movement (maximum 9 g/d). Kaolin-pectin formulations are not absorbed and have no significant adverse effects except constipation. They should not be taken within 2 hours of other medications (which they may bind). 

Viscosity poses a similar problem in the production of pulp wash concentrate. Pulp wash consists of juice solids obtained by countercurrent washing of pulp after its separation from juice. On a °Brix basis, pulp wash liquids are higher in pectin than juice from which the pulp has been screened (19). Concentration of pulp wash above 40°Brix is at times hampered by excessive pectin levels (20). To control viscosity processors may be forced to reduce finisher pressure to minimize pectin extraction, thereby curtailing yield. A more effective solution is to treat pulp wash with pectinases to reduce pectin levels (21). If pectinases are incorporated into the wash water, this method has the advantage of increasing total solids yield by reducing juice retention in the pulp. 

Oral 2.5 mg (with 0.025 mg atropine sulfate) tablets and liquid Kaolin/pectin (generic, Kaopectate, others)... 

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