Guar+Gum


 * Guar gum **, also called ** guaran ** , is a galactomannan . It is primarily the ground endosperm of guar beans . The guar seeds are dehusked, milled and screened to obtain the guar gum. It is typically produced as a free-flowing, pale, off-white-colored, coarse to fine ground powder. This is not gum for chewing, be careful.

Chemical composition
<span style="background-color: #f9f9f9; border-bottom-color: #cccccc; border-bottom-style: solid; border-bottom-width: 1px; border-left-color: #cccccc; border-left-style: solid; border-left-width: 1px; border-right-color: #cccccc; border-right-style: solid; border-right-width: 1px; border-top-color: #cccccc; border-top-style: solid; border-top-width: 1px; clear: right; display: block; float: right; font-family: sans-serif; font-size: 12px; margin-bottom: 1.3em; margin-left: 1.4em; margin-right: 0px; margin-top: 0.5em; min-width: 100px; overflow-x: hidden; overflow-y: hidden; text-align: center; width: 222px;">  Chemically, guar gum is a [|polysaccharide] composed of the [|sugars] [|galactose] and [|mannose]. The backbone is a linear chain of β 1,4-linked mannose residues to which galactose residues are 1,6-linked at every second mannose, forming short side-branches. === Solubility and viscosity === Guar gum is more soluble than [|locust bean gum] and is a better stabilizer, as it has more [|galactose] branch points. Unlike locust bean gum, it is not self-gelling.[|[6]] However, either [|borax] or [|calcium] can [|cross-link] guar gum, causing it to [|gel]. In water, it is [|nonionic] and [|hydrocolloidal]. It is not affected by ionic strength or <span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; background-position: initial initial; background-repeat: initial initial; color: #0b0080; text-decoration: none;">[|pH], but will degrade at pH extremes at temperature (e.g. pH 3 at 50 °C).<span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; color: #0b0080; line-height: 1em; text-decoration: none; white-space: nowrap;">[|[6]] It remains stable in solution over pH range 5-7. Strong <span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; background-position: initial initial; background-repeat: initial initial; color: #0b0080; text-decoration: none;">[|acids] cause<span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; background-position: initial initial; background-repeat: initial initial; color: #0b0080; text-decoration: none;">[|hydrolysis] and loss of viscosity, and alkalies in strong concentration also tend to reduce viscosity. It is insoluble in most hydrocarbon solvents. Guar gum shows high low-shear <span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; background-position: initial initial; background-repeat: initial initial; color: #0b0080; text-decoration: none;">[|viscosity] but is strongly shear-thinning. It is very <span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; background-position: initial initial; background-repeat: initial initial; color: #0b0080; text-decoration: none;">[|thixotropic] above 1% concentration, but below 0.3%, the thixotropy is slight. It has much greater low-shear viscosity than that of locust bean gum, and also generally greater than that of other hydrocolloids. Guar gum shows viscosity synergy with <span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; background-position: initial initial; background-repeat: initial initial; color: #0b0080; text-decoration: none;">[|xanthan gum]. Guar gum and<span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; background-position: initial initial; background-repeat: initial initial; color: #0b0080; text-decoration: none;">[|micellar casein] mixtures can be slightly thixotropic if a biphase system forms.<span style="background-attachment: initial; background-clip: initial; background-color: initial; background-image: none; background-origin: initial; color: #0b0080; line-height: 1em; text-decoration: none; white-space: nowrap;">[|[6]][|[7]]

Thickening
Guar gum is economical because it has almost eight times the water-thickening potency of cornstarch - only a very small quantity is needed for producing sufficient viscosity. Thus, it can be used in various multiphase formulations: as an emulsifier because it helps to prevent oil droplets from coalescing, and/or as a stabilizer because it helps to prevent solid particles from settling.

Ice crystal growth
Guar gum retards ice crystal growth nonspecifically by slowing mass transfer across the solid/liquid interface. It shows good stability during freeze-thaw cycles.

Grading
Guar Gum is analysed for

Test Test Method Test Test Method Colour TP/09 Acid insoluble residue TP/30 Viscosity TP/10/04 Fat content TP/18 Granulation(Mesh) TP/21 Ash content TP/12 Moisture, pH TP/1 and TP/29 Gum content TP/03 Protein TP/05 Heavy metals TP/13 Insolubles Ash TP/11 Filterability TP/20A

Guar Gum Powder Standards are:


 * HS-Code- 130 232 30
 * CAS No.- 9000-30-0
 * EEC No.- E 412
 * BT No.- 1302 3290
 * EINECS No. - 232-536-8
 * Imco Code- Harmless

Guar Gum Manufacturing Process

Depending upon the requirement of end product various processing techniques are used. The commercial production of Guar gum is normally undertaken by using process of roasting, differential attrition, sieving and polishing.

Food grade guar gum is manufactured in stages. It is very important to select guar split in this process. The split is screened to clean it and then soaked to prehydrate it in a double cone mixer. The prehydrating stage is very important because it determines the rate of hydration of the final product.

The soaked splits, which have reasonably high moisture content, are passed through a flaker. The flaked guar split is ground and then dried. The powder is screened through rotary screens to deliver required particle size. Oversize particles are either recycled to main Ultra fine or reground in a separate regrind plant, according to the viscosity requirement.

This stage helps to reduce the load at the grinder. The soaked splits are difficult to grind. Direct grinding of those generates more heat in the grinder which is not desired in the process as it reduces the hydration of the product. Through the heating, grinding, and polishing process, the husk is separated from the endosperm halves and the refined Guar Gum split is obtained. Through the further grinding process, the refined Guar split is then treated and converted into powder.

The split manufacturing process yields husk and germ called “Guar Meal”, widely sold in the international market as cattle feed. It is high in protein and contains “Oil and Albuminoids”, about 50% in germ and about 25% in husks. The quality of the food grade guar gum powder is defined from its particle size, rate of hydration, and microbial content. E412 guar gum is an important natural food supplement with high nutritional value.

Manufacturers define different grades and qualities of guar gum by the particle size, the viscosity generated with a given concentration, and the rate at which that viscosity develops. Coarse-mesh guar gums, will typically, but not always, develop viscosity more slowly. They may achieve a reasonably high viscosity, but will take longer to achieve. On the other hand, they will disperse better than fine-mesh, all conditions being equal. A finer mesh, like a 200 mesh, requires more effort to dissolve.

Modified forms of guar gum that are available commercially include enzyme-modified, cationic and hydropropyl guar.



Food applications
The largest market for guar gum is in the food industry. In the U.S., differing percentages are set for its allowable concentration in various food applications. In Europe, guar gum has EU food additive code E412.Xanthan (ZAN than) gum and guar (gwar) gum are the most frequently used gums in gluten-free recipes and gluten-free products. Applications include:
 * In baked goods, it increases dough yield, gives greater resiliency, and improves texture and shelf life; in pastry fillings, it prevents "weeping" (syneresis) of the water in the filling, keeping the pastry crust crisp.
 * In dairy products, it thickens milk, yogurt, kefir, and liquid cheese products, and helps maintain homogeneity and texture of ice creams and sherbets
 * For meat, it functions as a binder.
 * In condiments, it improves the stability and appearance of salad dressings, barbecue sauces , relishes, ketchups and others.
 * It is also used in dry soups, instant oatmeal, sweet desserts, canned fish in sauce, frozen food items and animal feed.