Monday, June 28, 2010
Gel formed on cooling. Molecules undergo a coil-helix transition followed by
aggregation of helices.
Gel formed on cooling. Molecules undergo a coil-helix transition followed by
aggregation of helices.
Gel formed on cooling in the presence of salts notably potassium salts. Molecules
undergo a coil-helix transition followed by aggregation of helices. Potassium ions bind specifically to the helices. Salts present reduce electrostatic repulsion between chains promoting aggregation.
Gel formed on cooling in the presence of salts. Molecules undergo a coil-helix transition followed by aggregation of helices. Salts present reduce electrostatic repulsion between chains promoting aggregation.
Low methoxyl (LM) pectin
Gels formed in the presence of divalent cations, notably calcium at low pH (3±4.5).
Molecules crosslinked by the cations. The low pH reduces intermolecular electrostatic repulsions.
Gels formed on cooling in the presence of salts. Molecules undergo a coil-helix transition followed by aggregation of helices. Salts reduce electrostatic repulsions between chains and promote aggregation. Multivalent ions can act by crosslinking chains. Low acyl gellan gels are thermoreversible at low salt concentrations but non-thermoreversible at higher salt contents (b 100mM) particularly in the presence of divalent cations.
Methyl cellulose and hydroxypropylmethyl cellulose
Gels formed on heating. Molecules associate on heating due to hydrophobic interaction of
Xanthan gum and locust bean gum or konjac mannan
Gels formed on cooling mixtures. Xanthan and polymannan chains associate following the xanthan coil-helix transition. For locust bean gum the galactose deficient regions are involved in the association.
Alginic acid 400 Thickening agent, stabiliser
Sodium alginate 401 Thickening agent, stabiliser, gelling agent
Potassium alginate 402 Thickening agent, stabiliser
Ammonium alginate 403 Thickening agent, stabiliser
Calcium alginate 404 Thickening agent, stabiliser, gelling agent,
Propylene glycol alginate 405 Thickener, emulsifier, stabiliser
Agar 406 Thickener, stabiliser, gelling agent
Carrageenan (including 407 Thickener, gelling agent, stabiliser,
Processed Euchema Seaweed 407a Thickener, stabiliser
Bakers yeast glycan 408 Thickener, gelling agent, stabiliser
Arabinogalactan 409 Thickener, gelling agent, stabiliser
Locust bean gum 410 Thickener, gelling agent
Oat gum 411 Thickener, stabiliser
Guar gum 412 Thickener, stabiliser and emulsifier
Tragacanth gum 413 Emulsifier, stabiliser, thickening agent
Gum arabic (Acacia gum) 414 Emulsifier, stabiliser, thickener
Xanthan gum 415 Thickener, stabiliser, emulsifier, foaming
Karaya gum 416 Emulsifier, stabiliser and thickening agent
Tara gum 417 Thickener, stabiliser
Gellan gum 418 Thickener, gelling agent and stabiliser
Gum ghatti 419 Thickener, stabiliser, emulsifier
Curdlan gum 424 Thickener, stabiliser
Konjac flour 425 Thickener
Soybean hemicellulose 426 Emulsifier, thickener, stabiliser, anticaking
Pectin 440 Thickener, stabiliser, gelling agent, emulsifier
Cellulose 460 Emulsifier, anticaking agent, texturiser,
Microcrystalline cellulose 460 (i) Emulsifier, anticaking agent, texturiser,
Powdered cellulose 460(ii) Anticaking agent, emulsifier, stabiliser and
Methyl cellulose 461 Thickener, emulsifier, stabiliser
Ethyl cellulose 462 Binder, filler
Hydroxypropyl cellulose 463 Thickener, emulsifier stabiliser
Hydroxypropyl methyl cellulose 464 Thickener, emulsifier stabiliser
Methyl ethyl cellulose 465 Thickener, emulsifier, stabiliser, foaming
Sodium carboxymethyl cellulose 466 Thickener, stabiliser, emulsifier
Ethyl hydroxyethyl cellulose 467 Thickener, stabiliser, emulsifier
Cross-linked sodium 468 Stabiliser, binder
Sodium carboxymethyl 469 Thickener, stabiliser
Dextrin (roasted starch) 1400
Acid treated starch 1401
Alkali treated starch 1402
Bleached starch 1403
Oxidised starch 1 404
Monostarch phosphate 1410
Distarch phosphate 1412
Phosphated distarch 1413
Acetylated starch 1414
Starch acetate 1420
Acetylated distarch adipate 1422
Hydroxypropyl starch 1440
Hydroxypropyl distarch phosphate 1442
Starch sodium octenyl succinate 1450
Starch, enzyme treated 1405
Wednesday, June 23, 2010
Guar Gum (Galactomanan) is a high molecular weight carbohydrate polymer made up of a large number of mannose and galactose unit linked together. The crude Guar Gum is a grayish white powder 90% of which dissolves in water. It is non ionic polysaccharide based on the milled endosperm of the guar bean whose average composition is :
Hydrocolloid : 23%
Fats : 40%
Proteins : 34%
|Colour Appearance||: Off White|
|Moisture||: 10 - 12%|
|RIA||: 2 - 2.5%|
|Protein||: 4 - 4.5%|
|Ash||: 1% Max|
|Gum Content||: 80 - 85%|
|PH||: 6 - 7|
|Heavy Metals||: Less than 20 ppm.|
|Arsenic||: 3 ppm|
|Lead||: Less than 5 ppm|
|Viscosity(Cold)||: ( 1% Sol. Brookf. Visc.RVT Mod. |
At 25oC Spi. No. 3/4, 20 rpm
2 hrs and 24 hrs. 2 Hrs. 3500 - 4000 4500 - 5000
24 Hrs. 4000 - 4500 5000 - 6500
|TPC||: Less than 10,000/gm. Less than 5000/gm.|
|Yeast Mold||: 300/gm 200/gm|
|Salmonella||: Ab. Ab.|
|E.Coli||: Ab. Ab.|
|Streptococcus||: Ab. Ab.|
|Pseudomonas||: Ab. Ab.|
|Passing||: 100 Mesh. 95 - 98% |
200 Mesh. 95 - 98%
300 Mesh. 90 - 99%
Sunday, June 20, 2010
Propriétés :le Guar est issu d'une légumineuse annuelle et se présente comme une farine de graine apportant un pouvoir épaississant à froid de texture courte, assez neutre au goût qui peut être mélangé à de nombreux ingrédients comme liant basse calorie. Le Guar est employé dans tous les usages réclamant un épaississant neutre : il apporte viscosité et améliore rétention en eau des recettes. C'est un produit très visqueux à de très faibles concentrations. De faible prix et très disponible, il fait l'objet de nombreuses transformations chimiques qui permettent d'étendre son usage à des applications non alimentaires comme les peintures ou les gels cosmétiques. Le Guar a le statut de fibre végétale soluble acalorique. Il est très neutre et ne développe pas de gels avec le Xanthane ni le Carraghénane comme d'autres molécules galactomannanes issues de la même famille botanique (Tara, Caroube, Cassia). Modifié de façon à réduire sa viscosité, il peut servir à remplacer des molécules comme les sucres ou les amidons.
Le Guar :
- Apporte de la viscosité à faible température (moins que tara, et caroube ou carraghénanes)
- Améliore la rétention d'eau des aliments (surtout guar modifié)
- Est facile d'usage : même proportion pour toutes les recettes, insensible au pH et à la présence de différents sels.
- Est insensible aux enzymes protéolytiques
- Est peu réactif avec d'autres molécules et peu à la température (ne change pas de propriétés)
- A une faible synergie avec le Xanthane sans toutefois donner un gel à température ambiante.
- Est économique car s'utilise à petite dose
Emploi : le Guar se dissout facilement et n'apporte que peu de goût et pas d'odeur. En grandes quantités il a une perception farineuse, collante. Souvent son taux d'usage ne dépasse pas 1%. Il est employé partout dans toutes sortes de recettes car sans interaction avec les autres additifs. En général, il sert surtout pour épaissir mais aussi dans les glaces et les produits surgelés pour limiter la formation de gros cristaux. En boulangerie le Guar donne du moelleux car il freine la levée et réduit les pertes d'eau de la pâte et freine le rancissement de l'amidon.
Préparation : Le Guar est une poudre blanche cassée, pratiquement inodore et assez farineuse.
- La mélanger avec 3 à 5 fois son poids en sucre (glucose, maltose ou saccharose) ou un autre ingrédient facile à disperser et plus abondant (farines, amidons).
- Le produit s'hydrate à froid mais il vaut mieux de la chaleur et un bon mixage.
- Il est synergique avec le Xanthane et constitue le produit le plus courant pour apporter de la viscosité. Il ne donne pas toute sa viscosité immédiatement et il faut préférer une qualité plus grossière pour limiter la viscosité immédiate mais faciliter la mise en solution.
Tuesday, June 15, 2010
Guar, or clusterbean, (Cyamopsis tetragonoloba (L.) Taub) is a drought-tolerant annual legume that was introduced into the United States from India in 1903. Commercial production of guar in the United States began in the early 1950s and has been concentrated in northern Texas and southwestern Oklahoma. The major world suppliers are India, Pakistan and the United States, with smaller acreages in Australia and Africa. In the early 1980s, Texas growers were planting about 100,000 acres annually. They harvested about half of the planted acreage and plowed the rest under as green manure.
Unlike the seeds of other legumes, the guar bean has a large endosperm. This spherical-shaped endosperm contains significant amounts of galactomannan gum (19 to 43% of the whole seed), which forms a viscous gel in cold water. Guar gum is the primary marketable product of the plant. India and Pakistan export much of their guar crop to the United States and other countries in the form of partially processed endosperm material. World demand for guar has increased in recent years, leading to crop introductions in several countries.
Like other legumes, guar is an excellent soil-building crop with respect to available nitrogen. Root nodules contain nitrogen-fixing bacteria, and crop residues, when plowed under, improve yields of succeeding crops.
In Asia, guar beans are used as a vegetable for human consumption, and the crop is also grown for cattle feed and as a green manure crop. In the United States, highly refined guar gum is used as a stiffener in soft ice cream, a stabilizer for cheeses, instant puddings and whipped cream substitutes, and as a meat binder. Most of the crop in the United States, however, is grown for a lower grade of guar gum, which is used in cloth and paper manufacture, oil well drilling muds, explosives, ore flotation, and a host of other industrial applications.
Guar gum consists of long branching polymers of mannose and galactose in a 2:1 ratio. After extraction of the gum, guar meal contains approximately 35% protein, which is about 95% digestible. The seed protein is low in methionine, like most legumes. Enough gum remains in the meal to make it an excellent feed pelleting material. Toasting improves its palatability to livestock and helps remove a trypsin inhibitor for non-ruminants.
III. Growth Habits:
Guar is an upright, coarse-growing summer annual legume known for its drought resistance. Its deep tap roots reach moisture deep below the soil surface. Most of the improved varieties of guar have glabrous (smooth, not hairy) leaves, stems and pods. Plants have single stems, fine branching or basal branching (depending on the variety) and grow to be 18 to 40 in. tall. Racemes are distributed on the main stem and lateral branches. Pods are generally 1 1/2 to 4 in. long and contain 5 to 12 seeds each. Seeds vary from dull-white to pink to light gray or black and range from 900 to 1,600 seeds/oz.
IV. Environment Requirements:
Guar tolerates high temperatures and dry conditions and is adapted to arid and semi-arid climates. Optimum temperature for root development is 77 to 95°F. When moisture is limited, the plant stops growing but doesn't die. While intermittent growth helps the plant survive drought, it also delays maturity. Growing season ranges from 60-90 days (determinate varieties) to 120-150 days (indeterminate varieties). Guar responds to irrigation during dry periods. It is grown without irrigation in areas with 10 to 40 in. of annual rainfall. Excessive rain or humidity after maturity causes the beans to turn black and shrivel, reducing their quality and marketability. While profitable seed production in southern U.S. areas of high rainfall and humidity is likely to be limited, guar can be successfully grown as a green manure crop under these conditions. Guar varieties that require a particular daylength to flower or day-neutral have been described. Considering these high soil temperatures and long growing season, successful guar production in Wisconsin and Minnesota is very unlikely.
Guar grows well under a wide range of soil conditions. It performs best on fertile, medium-textured and sandy loam soils with good structure and well-drained subsoils. Guar is susceptible to waterlogging. Guar is considered to be tolerant of both soil salinity and alkalinity.
Guar is an excellent soil-improving crop and fits well in a crop-rotation program with grain sorghum, small grains or vegetables. In Australia, guar was found to add 196 lb N/acre to the soil-plant system over three years. Increased yields can be expected from crops following guar because of increased soil nitrogen reserves. When used in rotation with cotton in Texas, researchers measured a 15% yield increase in cotton.
C. Seed Preparation and Germination:
Select seed that is uniform in color and size and is free from other crop and weed seed. New guar varieties have been released that have some resistance to diseases that once devastated fields of the crop. To prevent disease problems, select certified seed that does not contain seed of older varieties with less disease resistance.
Seed should be inoculated just before planting with a special guar inoculant or the cowpea (Group "E") inoculant. Exposure of inoculum to sunlight, heat and drying before planting can impair the effectiveness of the nitrogen-fixing bacteria. Seed should be planted in moist soil within 2 hours after inoculation. Fungicidal seed treatments may inhibit inoculation.
V. Cultural Practices:
A. Seedbed Preparation:
The seedbed should be firm and weed-free. Soil in the row should be ridged slightly to facilitate harvest of low-set beans.
B. Seeding Date:
Guar should be planted when soil temperature is above 70°F; the optimum soil temperature for germination is 86°F. A warm seedbed, adequate soil moisture and warm growing weather are essential for establishment of a stand. In Texas, June plantings of guar produce more reproductive buds than July plantings, resulting in substantially higher yields. Thus, production of this crop in the Upper Midwest is unlikely.
C. Method and Rate of Seeding:
1. Method of Planting: Guar is usually planted in 36 to 40 in. rows with a row crop planter. However, it can be broadcast seeded or planted in narrower rows with a grain drill if moisture is adequate. A planting depth of 1 to 1 1/2 in. is usually recommended. If guar seed is crushed, gumming or clogging of equipment may occur. To prevent clogging, holes on the bottom sides of the plates should be straight, rather than beveled or tapered. Adding graphite or a dry detergent to the seed box and reducing seed weight on the plates by filling the planter box only about one-third full may also help prevent gumming during planting.
2. Rate of Planting: Although some studies have found little effect on yield when seeding rates ranged from 5 to 44 lb seed/acre, other researchers have indicated an optimum seeding rate of 5 to 9 viable seeds/ft of row (30 in. rows). Current Texas recommendations are 5 lb/acre for 30 in. rows and 12 lb/acre for broadcast. Broadcasting should be practiced only where moisture is sufficient to support the higher plant population.
D. Fertility and Lime Requirements:
Nitrogen is not thought to be limiting in guar when the plants are well nodulated. Like most legumes, guar usually requires application of a rather high level of phosphorus (20 to 30 lb of P2O5/acre) and medium levels of potash (40 to 50 lb of K2O/acre). For highest yield, fertilize according to soil test results. Apply fertilizer below the seed before planting or to the side and below the seed at planting. Sulfur fertilizers have been found to affect guar on some soils, and zinc deficiency is a common problem in India.
Moderately alkaline soils are considered desirable for guar crop production (pH 7.0 to 8.0).
E. Variety Selection:
There have been notable improvements in guar varieties developed in the last 30 years. The newer cultivars are much more disease resistant with higher yields. Pod set in improved varieties is higher, and pods are well distributed on the main stem and branches, increasing harvest efficiency. The multiple branching of these newer cultivars also produces more pods.
Only the earliest-maturing varieties are recommended for production in Wisconsin and Minnesota.
Brooks, released in 1964, was the first improved variety, replacing Texsel and Groehler. Brooks has been grown on most of the guar acreage since 1966, but is rapidly being replaced by two newer releases, Kinman and Esser. Brooks is high-yielding and resistant to the major guar diseases, Alternaria leaf spot and bacterial blight. It is medium to late in maturity. Plants have a fine-branching growth habit and small racemes of medium-sized pods. Leaves and stem are glabrous. The seed is of medium size.
Hall is a slightly later-maturing variety than Brooks, and therefore not recommended for production in the Upper Midwest. It is resistant to bacterial blight and Alternaria leaf spot. Plants are relatively tall, coarse, finely branched, and produce small racemes of medium-sized pods. Leaves and stems are glabrous. This variety is best adapted to heavier soil types and higher elevations.
Mills is an early-maturing variety which also is resistant to bacterial blight and Alternaria leaf spot. Plants are short and finely branched and produce small racemes with relatively large pods. Leaves and stems are pubescent (hairy). Seeds are larger than those of Brooks and Hall. In dry seasons, Mills does not grow tall enough for efficient harvest. Yields are generally lower than those of Brooks and Hall.
Kinman, released by the Texas Agricultural Experiment Station, the USDA-ARS and the Oklahoma Agricultural Experiment Station in 1975, is derived from Brooks and Mills. Kinman is about 7 days earlier in maturity than Hall and of the same maturity as Brooks. It is highly resistant to bacterial leaf blight and Alternaria leaf spot. Kinman is slightly taller and coarser-stemmed than Brooks, but less so than Hall. It is fine branched and produces small-to-medium sized racemes. Seed pods are medium in length and generally contain from 7 to 9 seeds each. Seed of Kinman is slightly larger than Brooks. In 41 yield trials at eight locations in Texas and Oklahoma from 1971 to 1976, Kinman produced 17% more seed than Brooks.
Esser, released with Kinman in 1975, is a selection from progeny of the same Brooks × Mills cross. It is medium to late in maturity and therefore is probably not a good cultivar for Wisconsin and Minnesota. It has high resistance to Alternaria leaf spot and bacterial leaf blight. Esser has shown superior disease tolerance to Brooks and Kinman under severe bacterial blight conditions. Esser plants have Brooks' fine branching growth habit, but Esser has stronger main stems and fewer lateral branches. Esser produces small racemes with medium-sized pods.
Lewis, released by the Texas Agricultural Station and the USDA- ARS in 1986, is a selection from a cross of a glabrous parent with a pubescent (hairy) parent. Lewis is a medium-to-late maturing variety that is highly resistant to Alternaria leaf spot and bacterial leaf blight. Leaves, stems and pods are glabrous. Plants have a basal branching growth habit. The main stem and the basal branches possess short internodes with racemes initiated at each node over the entire plant. Plants are of average height, and racemes and pods are of medium length. Pods generally contain 5 to 9 seeds of average size. In 10 yield tests at five Texas locations during 1980-1983, Lewis produced mean seed yields approximately 25% higher than Kinman and 21% higher than Esser (Table 1).
Table 1. Yields of five guar varieties in Texas from 1980 to 1983.
1Test received supplemental irrigation.
2Disease was present in the test.
Source: Stafford, R.E. 1986. Lewis: A New Guar Variety. Texas Agricultural Experiment Station Bulletin L-2177, February 1986. Texas A&M University System, College Station, Texas.
F. Weed Control:
Young guar plants grow slowly and are particularly susceptible to weed problems. Weeds can reduce yields and create harvesting problems.
1. Mechanical control: Guar should not be seeded in fields heavily infested with Johnsongrass (Sorghum halepense) and other perennial weeds. Early preparation of land and mechanical cultivations during the growing season will help minimize weed problems. Covering the lower branches during cultivation may promote development of disease and increase harvest difficulties.
2. Chemical: Treflan (trifluralin) is registered for use on guar as a preplant incorporated treatment to control most annual grass and several annual broadleaf weeds. Follow label instructions carefully for different soil types.
G. Diseases and Their Control:
Selecting disease-resistant varieties and high-quality certified seed is the best defense against disease problems. There are two major diseases of guar worldwide:
1. Alternaria leaf or target spot (Alternaria cucumerina var. cyamopsidis): This fungal disease may become severe during periods of heavy dew and high humidity. It causes a brown target-like lesion on the leaf between bloom and pod set. As the disease progresses, lesions enlarge, join and cause leaf drop.
2. Bacterial blight (Xanthomonas cyamopsidis): This seed-borne disease can cause loss of plants from the seedling stage until maturity. Symptoms include large angular necrotic lesions at the tips of leaves, which cause defoliation and black streaking of the stems. This is potentially the greatest disease hazard to guar.
H. Insects and Other Predators and Their Control:
The guar midge (Contarinia texana) is the primary guar insect pest in the Southwest. Heavy midge infestations have caused up to 30% loss in seed production. Guar midge infestations are generally heavier in fields with sandy or sandy loam soils.
Damage to guar is caused by the larvae, which develop in the guar buds. Infested buds eventually dry up and fall from the plant. The adult female midge deposits her eggs in developing buds. After larvae complete their development, they drop from the buds to the ground to pupate. There are several generations each year.
Rainfall or sprinkler irrigation can reduce midge populations drastically. However, field inspection should continue because midge infestation problems may increase again as a result of improved growing conditions. Control midges while guar is producing buds -- primarily between 45 and 90 days after emergence.
Other guar insect pests include the gall midge (Asphondylia sp.), three-cornered alfalfa hoppers, pea aphids, white grubs, thrips, and whiteflies. Storage pests have not been a problem with guar.
Since guar beans generally do not shatter, the crop can be direct-combined as soon after maturity as possible. Harvest does not generally take place until after frost in northern regions. At maturity, the seed pods are brown and dry, and seed moisture content is less than 14%. Gramoxone (paraquat) can be used as a harvest aid to speed up drying and to kill weeds prior to frost. Apply when pods are fully mature. Preharvest interval is 4 days. Do not graze treated areas or use the treated forage for animal feed.
Guar beans can be harvested with an ordinary grain combine. The cylinder should be slowed and the combine speed reduced to a rate that will permit proper threshing of the beans. A high fan speed can be used to clean out foreign material. Reel speed should be slightly greater than combine ground speed. Improper reel speed can shatter seed pods. Reels should be set just deep enough in the guar to control the stalks, and should be about 6 to 12 in. ahead of the cutterbar. Some operators replace the wooden reel bats with 1/2 in. steel rods to reduce shattering. When harvested for hay, guar leaves drop readily unless extreme care is taken during the curing process. For hay, the crop should be cut when the first lower pods turn brown.
Guar can be harvested for seed and then plowed under or used as a mulch. If seed is not harvested, guar used for green manure should be turned under when the lower pods begin to turn brown.
J. Drying, Storage and Seed Quality:
Following harvest, the seed is graded for size and cleaned to remove shrunken seed and crop residue. Little information is available on optimum storage conditions for guar, but this has not been identified as a problem in most production guides. Following cleaning, milling for gum extraction may proceed.
The principal factors that decrease seed quality in guar are seed blackening and the production of small and shrunken seed. White seed is preferred for many food applications, and black seed is often discounted. Darkening tends to follow patterns of increasing rainfall, especially when it occurs during the period of seed maturation.
Small seed contains less endosperm and therefore is less desirable for milling. Late flowering, diseases, insects and low moisture can cause small seed (preferred size is 4 mm).
VI. Yield Potential and Performance Results:
Production practices and rainfall during the growing season cause seed yields to vary from about 300 to 2,000 lb/acre. Yields of several varieties in Texas are shown in Table 1. Experimental plantings of guar at Rosemont, Minnesota, have resulted in plants that bloomed but produced very little seed.
VII. Economics of Production and Markets:
Income and production costs for guar vary from year to year and according to soil types. Production costs often vary by $20 to $40/acre between farms because of different fertilizer usage and other production practices.
Demand for guar is increasing because of the wide use of the gum in more products and efforts of dealers to obtain a larger percentage of the gum from domestic sources. Growth in the early 1980s was estimated at 10% annually. Grade factors considered by the purchaser are the moisture, foreign material and test weight. Identify a market and secure a contract, if possible, before growing guar for bean production.
The value of guar as a soil builder to increase yields of succeeding crops should not be overlooked when considering guar as an alternative crop.
VIII. Information Sources:
- Guar: A Potential Industrial Crop for the Dry Tropics of Australia. 1982. K.J. Jackson, J.A. Doughton. J. of the Australia Inst. of Agric. Science.
- Kinman and Esser - New Guar Varieties. 1975. Texas Agricultural Experiment Station Bulletin L-1356. Texas A&M University System, College Station, Texas.
- Lewis - A New Guar Variety. 1986. R.E. Stafford. Texas Agricultural Experiment Station Bulletin L-2177. Texas A&M University System, College Station, Texas.
- Keys to Profitable Guar Production. L.D. Tripp, D.A. Lovelace, E.P. Boring. Texas Agricultural Extension Service Bulletin B- 1399. Texas A&M University System, College Station, Texas.
- Guar: Production, Nutrition and Industrial Use. 1979. R. Whistler, and T. Hymowitz. Purdue University Press, Lafayette, Indiana 47907.
References to pesticide products in this publication are for your convenience and are not an endorsement of one product over other similar products. You are responsible for using pesticides according to the manufacturer's current label directions. Follow directions exactly to protect people and the environment from pesticide exposure. Failure to do so violates the law.
Guar gum is a water-soluble fiber that acts as a bulk forming laxative, and as such, it is claimed to be effective in promoting regular bowel movements and relieve constipation and chronic related functional bowel ailments such as diverticulosis, Crohn's disease, colitis and irritable bowel syndrome, among others. The increased mass in the intestines stimulates the movement of waste and toxins from the system, which is particularly helpful for good colon health, because it speeds the removal of waste and bacteria from the bowel and colon. In addition, because it is soluble, it is also able to absorb toxic substances (bacteria) that cause infective diarrhea.
Several studies have found significant decreases in human serum cholesterol levels following guar gum ingestion. These decreases are thought to be a function of its high soluble fiber content.
Guar gum has been considered of interest with regards to both weight loss and diabetic diets. It is a thermogenic substance. Moreover, its low digestibility lends its use in recipes as a filler, which can help to provide satiety, or slow the digestion of a meal, thus lowering the glycemic index of that meal. In the late 1980s, guar gum was used and heavily promoted in several weight loss products. The U.S. Food and Drug Administration eventually recalled these due to reports of esophageal blockage from insufficient fluid intake, after one brand alone caused at least 10 users to be hospitalized and a death. For this reason, guar gum is no longer approved for use in over-the-counter weight loss aids in the United States. Moreover, a meta-analysis that combined the results of 11 randomized controlled trials found that guar gum supplements were not effective in reducing body weight.
Two Japanese studies using rats showed that guar gum supports increased absorption of calcium occurring in the colon instead of in the small intestine. This means that lesser amounts of calcium may be consumed in order to obtain its recommended minimum daily intake (RDI). This has obvious implications for reduced calorie diets, since calcium rich dairy products tend to be high in calories.
However, guar gum is also capable of reducing the absorbability of dietary minerals (other than calcium), when foods and/or nutritional supplements containing them are consumed concomitantly with it. However, this is less of a concern with guar gum than with various nonsoluble dietary fibers.
Some studies have found guar gum to improve dietary glucose tolerance. Research has revealed that the water soluble fiber in it may help people with diabetes by slowing the absorption of sugars by the small intestine. Although the rate of absorption is reduced the amount of sugar absorbed is the same overall. This helps diabetic patients by lowering the amount of insulin needed to keep the blood glucose at a normal level.
It also functions as an adjuvant for diabetic drugs that are sometimes employed for the treatment of noninsulin dependent diabetes. The effect is to help lower blood glucose levels. Thus, diabetic patients who are taking drugs should consult their doctors before supplementing with 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.
Guar gum is extracted from the guar bean, where it acts as a food and water store. The guar bean is principally grown in India and Pakistan, with smaller crops grown in the U.S., Australia, China, and Africa. The drought-resistant guar bean can be eaten as a green bean, fed to cattle, or used in green manure.
According to a Reuters report, India accounts for about 80 percent of the global trade in guar products.. India exported 11 billion rupees worth of guar products in 2007/08 financial year ending March 2008. Pakistan trails India in the global trade. Industrial guar gum is the most sought after guar product, and accounts for about 45 percent of the total demand. Industrial gum is used as a controlling agent in oil wells to facilitate easy drilling and prevent fluid loss.
In 2007, the Indian industry was hit by a contamination crisis when the European Union suspended imports of Indian guar gum after excessive levels of dioxins were found in one shipment.
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 emulsifier as it has more galactose branch points. Unlike locust bean gum, it is not self-gelling. 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 pH, but will degrade at pH extremes at temperature (e.g. pH 3 at 50°C). It remains stable in solution over pH range 5-7. Strong acids cause 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 viscosity but is strongly shear-thinning. It is very thixotropic above concentration 1%, 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 xanthan gum. Guar gum and micellar casein mixtures can be slightly thixotropic if a biphase system forms.
Guar gum is economical because it has almost 8 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 multi-phase 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.
Guar gum retards ice crystal growth non-specifically by slowing mass transfer across the solid/liquid interface. It shows good stability during freeze-thaw cycles.
Manufacturers define different grades and qualities of guar gum by the particle size, the viscosity that is 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.
- Textile industry – sizing, finishing and printing
- Paper industry – improved sheet formation, folding and denser surface for printing
- Explosives industry – as waterproofing agent mixed with ammonium nitrate, nitroglycerin etc.
- Pharmaceutical industry – as binder or as disintegrator in tablets
- Cosmetics and toiletries industries – thickener in toothpastes, conditioner in shampoos (usually in a chemically modified version)
- Oil and gas drilling, hydraulic fracturing
- Hydroseeding – formation of seed bearing "guar tack"
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.
- Baked goods - 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.
- Dairy - thickens milk, yogurt, kefir, and liquid cheese products; helps maintain homogeneity and texture of ice creams and sherbets
- Dressing and sauces - improves the stability and appearance of salad dressings, barbecue sauces, relishes, ketchups and others
- Misc. - Dry soups, instant oatmeal, sweet desserts, canned fish in sauce, frozen food items and animal feed.
and its derivatives are widely used in various industries as per its needs. It is used in industries such as food, animal feed, textile, pharmaceuticals, personal care, health care, nutrition, cosmetics, paper, explosives, mining and oil drilling.
Guar Gum is mainly used as a
- Natural thickener
- Bonding agent
- Gelling agent
- Soil Stabiliser
- Natural fiber
- Fracturing agent
In Food Industry Guar gum is used as gelling, viscosifying, thickening, clouding, and binding agent as well as used for stabilization, emulsification, preservation, water retention, enhancement of water soluble fiber content etc.
Some food products in which guar gum powder is used:
- Ice Cream, soft drinks & concentrates, puddings
- Chocolate milk, flavoured milks
- Jams, jellies, fruit spreads, jelly sweets
- Bread, biscuit and other baked foods
- Ham and sausages
- Soft cheese and cheese spreads
- Canned or retorted food of fish and meat
- Myonnaise, ketchup, sauce and dressings
- Noodles and pasta
In Frozen Food Products: Guar gum reduces crystal formation, act as a binder & stabilizer to extend shelf life of Ice-cream.
In Baked Food Products: Guar gum provides unparallel moisture preservation to the dough and retards fat penetration in baked foods.
In Dairy Products: Guar Gum improves texture, maintains uniform viscosity and color.
In Sauces & Salad preparations: Guar gum acts as a water binder in sauces & salad dressings and reduces water & oil separation.
In Confections: Guar gum controls viscosity, bloom, gel creation, glazing & moisture retention to produce the highest grade confectionary.
In Beverages: Guar gum provides outstanding viscosity control and reduces calories value in low calories beverages.
In Pet Food: Guar gum forms gels & retains moisture, acts as a thickening, stabilizer and suspending agent for veterinary preparations.
- Anti-acid formulations
- Tablet binding and disintegration agent
- Controlled drug delivery systems
- Slimming aids
- Nutritional foods
Guar Gum is an important non-caloric source of soluble dietary fiber. Guar gum powder is widely used in capsules as dietary fiber. Fiber is a very important element of any healthy diet. It is useful in clear and cleanses the intestinal system since fiber can not be digested. This keeps the intestines functioning properly and also improves certain disorders and ailments. All natural fiber diet works with body to achieve a feeling of fullness and to reduce hunger. Its synergistic mix of guar gum and fiber mixture when taken with water expands in stomach to produce a feeling of fullness.
- Used as a thickener, protective colloid in Skin care products, creams and lotions.
- Also used in toothpaste, and shaving cream for easy extruding from the container tube.
In Industrial Applications guar gum powder is a very versatile product and finds its different applications, as thickening, sizing agent, wet-end strength additive, gelling agent and water barrier, flocculation aid, for waste water treatment, as emulsifier, binder. Also used for mud formulations, enhanced oil recovery, polymer flooding, well treatment, lost circulation plugging etc.
Guar Gum Industrial grade powder is used in some industries as follows:
- Textile Printing & Sizing
- Fire Fighting
- Printing Inks
- Mosquito Mats
- Synthetic Resins
- Paper Industry
- Battery Electrolytes
- Water Treatment
- Floatation Agent
- Water Paint
- Carpet Printing
- Oil Well Drilling
- Guar Gum provides better properties compared to substitutes.
- It gives denser surface to the paper used for printing.
- Guar Gum imparts improved erasive and writing properties, better bonding strength and increased hardness.
- Due to improved adhesion, it gives better breaking, mullen and folding strengths.
- Guar Gum gives excellent film forming and thickening properties when used for textile sizing, finishing and printing.
- It reduces warp breakage, reduces dusting while sizing and gives better efficiency in production.
- Industrial grade Guar gum powder are use in oil well fracturing, oil well stimulation, mud drilling and industrial applications and preparations as a stabilizer, thickener and suspending agent.
- It is a natural, fast hydrating dispersible guar gum and is diesel slurriable.
- In the oil field industry, guar gum is used as a surfactant, synthetic polymer and deformer ideally suited for all rheological requirements of water-based and brine-based drilling fluids.
- High viscosity Guar Gum products are used as drilling aids in oil well drilling, geological drilling and water drilling.
- These products are used as viscosifiers to maintain drilling mud viscosities that enable drilling fluids to remove drill waste from deep holes.
- Guar gum products also reduce friction in the holes, and so minimising power requirements. Some Guar Gum products act to minimise water loss should occur in broken geological formations.
- Guar gum is widely used as a flocculants to produce liquid solid separation
- Guar gum is also used in flotation. It acts as a depressant for talc or insoluble gangue mined along with the valuable minerals
- Gelling agents for gel sausage type explosives and pumpable slurry explosives
- Cross linking agents for gel and slurry explosives systems
Wednesday, June 9, 2010
Guar gum (E412, also called guaran) is extracted from the seed of the leguminous shrub Cyamopsis tetragonoloba, where it acts as a food and water store.
Guar gum is a galactomannan similar to locust bean gum consisting of a (1" width="22" height="10">4)-linked β-D-mannopyranose backbone with branchpoints from their 6-positions linked to α-D-galactose (that is, 1" width="22" height="10">6-linked-α-D-galactopyranose). There are between 1.5 - 2 mannose residues for every galactose residue.
Guar gum is made up of non-ionic polydisperse rod-shaped polymers consisting of molecules (longer than found in locust bean gum) made up of about 10,000 residues. Higher galactose substitution also increases the stiffness (that is, decreases the flexibility) but reduces the overall extensibility and radius of gyration of the isolated chains . The galactose residues prevent strong chain interactions as few unsubstituted clear areas have the minimum number (about 6) required for the formation of junction zones. Of the different possible galactose substitution patterns, the extremes of block substitution and alternating substitution give rise to the stiffer, with greater radius of gyration, and most flexible conformations respectively (random substitution being intermediate) . Its persistence length is greater than that for locust bean gum at about 10 nm . If the galactose residues were perfectly randomized, it unlikely that molecules would have more than one such area capable of acting as a junction zone, so disallowing gel formation. A block substitution pattern, for which there is some experimental evidence , would allow junction zone formation if the blocks were of sufficient length. Enzymatic hydrolysis of some of the galactose side chains (for example, using legume α-galactosidase) may allow guar gum to be used to replace a dwindling locust bean gum supply.
Guar gum is an economical thickener and stabilizer. It hydrates fairly rapidly in cold water to give highly viscous pseudoplastic solutions of generally greater low-shear viscosity when compared with other hydrocolloids and much greater than that of locust bean gum. High concentrations (~ 1%) are very thixotropic but lower concentrations (~ 0.3%) are far less so. Guar gum is more soluble than locust bean gum and a better emulsifier as it has more galactose branch points. Unlike locust bean gum, it does not form gels but does show good stability to freeze-thaw cycles. Guar gum shows high low-shear viscosity but is strongly shear-thinning. Being non-ionic, it is not affected by ionic strength or pH but will degrade at pH extremes at temperature (for example, pH 3 at 50°C). It shows viscosity synergy with xanthan gum. With casein, it becomes slightly thixotropic forming a biphasic system containing casein micelles.
Applications of Guar Gum
Guar Gum for Food, Pharmaceutical & Dialectic Industries:
Guar Gum Powder for Food, Pharmaceutical, Dialectic Industries
Guar Gum in pure form when used in the ice creams acts as a superior stabiliser and gives the right texture by preventing the formation of coarse ice crystals. Guar gum is used as a thickener and stabiliser in food and pharmaceuticals. The present trend is to use agro-based Guar Gum only for Ice cream, without any Additives or Preservatives, in place of Carboxymethyl Cellulose (CMC), which is a chemical derivative of cellulose and therefore objectionable, in Europe , Japan and America for Food Products.
In squashes, sauces and sherbets, it functions as a suspending agent and as a stabiliser. It has got a low calorific food value, and it is an excellent bulk laxative. It is used as a suspending agent for Calamine and Barium Sulphate. It increases the mechanical strength of tablets during pressing. It readily disperses in water. It is used in jellies and ointments as a thickener. It imparts good viscosity and gives better foam stability in shampoos. It is compatible with glycerol and is used in tooth-pastes.
Guar Gum for Bakery Industry:
It is used in the Bakery Industry, in Bread, Pastry, Cakes and Cookies. On dry mixing prior to dough making in Bread, it helps to retain moisture and hence the weight of Bread. It keeps the Bread smooth, pliable and fresh for longer time and imparts milky white bleached appearance to Bread.
Guar Gum Powder for Bakery Industry
Guar Gum for Grass Growing / Erosion Control :
Guar Gum Powder for Grass Growing, Erosion Control Industry
Guar gum has a major application in the grass growing and erosion control industry where it is used as a water binder to retain moisture on the soil surface, particularly on slopes where the addition of guar gum to the water systems will help to anchor the hydro seeding mixture to the slopes and seal in the moisture. It is used in systems that protect against hydraulic lift and shear forces created by high-volume discharges, so whether grass is grown on slopes, channels, or straight-aways, from roadside to residential lawns, golf urses to athletic fields to parks, using guar gum prevents soil erosion and enhances grass growing.
Guar Gum for Cosmetics:
Guar Gum is soluble in cold and hot water and this solution is not attacked by Bacteria. Guar Gum Protective colloid forming capacity results in emulsion stabilisation. It is also a good thickener and suspending agent in Cosmetics.
Guar Gum Powder for Cosmetics
Guar Gum for Fish Farming :
Guar Gum Powder for Fish Farming
Guar gum is used as a binder in the fish feed pellets. The binder keeps the pellets from disintegrating quickly when placed in water and greatly reduces the consumption of fish feed in the pond.
Guar Gum for Oil Well Drilling :
Guar Gum when used in oil well drilling muds, gives a better colloid thereby reducing water losses. It regulates the viscosity of mud solution, stabilises and regulates the flow properties of the drilling muds. We are making Gelling Agent II and Gelling Agent III.
SPECIFICATION OF GELLING AGENT GRADE II
SPECIFICATION OF GELLING AGENT GRADE III
Guar Gum Powder for Oil Well Drilling
Guar Gum for Explosives (as Water Blocking Agent in Nitro-glycerine, Slurry Explosives, Ammonium Nitrate & Dynamite Explosives):
Guar Gum Powder for Explosives
By mixing Guar Gum in Ammonium Nitrate, Nitro-glycerine & Oil Explosives, even in wet conditions explosive property is maintained. This is due to the better swelling, water blocking and gelling properties of Guar Gum.
Guar Gum for Paper Industry:
Guar Gum is used in paper manufacture as a better additive. It gives denser surface to the paper used for printing. Guar Gum imparts improved erasive and writing properties, better bonding strength and increased hardness. Due to improved adhesion, it gives better breaking, mullen and folding strengths.
Guar Gum Powder for Paper Industry
Guar Gum for Mining :
Guar Gum Powder for Mining
Guar gum is used in mining potash, gold, copper and platinum group metals (PGM) as a flocculent and as a depressant.
Guar Gum is also used in the following industries:
* Insecticides & Pesticides
* Detergents & Soaps
* Paint Industry
* Electrodes & Brazing Fluxes
* Leather Industry
* Tobacco Processing
* Pencils Crayons
* Mosquito Coils