Arab properties

Gum ghatti is the calcium and magnesium salt of a complex polysaccharide which contains L-arabinose, D-galactose, D-mannose, and D-xylose and D-glucuronic acid (48) and has a molecular weight of approximately 12,000. On dispersion in water, gum ghatti forms viscous solutions of viscosity intermediate between those of gum arabic and gum karaya. These dispersions have emulsification and adhesive properties equivalent to or superior to those described for gum arabic. 

Larch gum is readily soluble in water. The viscosity of these solutions is lower than that of most other natural gums and solutions of over 40% soHds are easily prepared. These highly concentrated solutions are also unusual because of their Newtonian flow properties. Larch gum reduces the surface tension of water solutions and the interfacial tension existing in water and oil mixtures, and thus is an effective emulsifying agent. As a result of these properties, larch gum has been used in foods and can serve as a gum arabic substitute. 

Opium is the dried, powdered sap of the unripe seed pod of Papaver somniferum, a poppy plant indigenous to Asia minor. Theophrastus described its medical properties in the third century BC, but the Sumerians, ca BC 4000, probably perceived its utility. Arab physicians knew of the dmg, and Arab traders carried it to the Orient where it was used as a treatment for dysentery. Paracelsus is credited with repopularizing the dmg in western Europe in the early sixteenth century by formulating opium into "laudanum", which is still in use. More than 20 different alkaloids (qv) of two different classes comprise 25% of the weight of dry opium. The benzylisoquinolines, characterized by papaverine [58-74-2] (1.0%), a smooth muscle relaxant, and noscapine [128-62-1] (6.0%), an antitussive agent, do not have any analgesic effects. The phenanthrenes, the second group, are the more common and include 10% morphine (1, = R = H), 0.5% codeine [76-57-3], C gH2 N03, (1, R = H, R = CH3), and 0.2 thebaine [115-37-7], C 2H2 N03, (2). 

Table 1. Comparative chemical composition and some properties of Gum arabic taken from Acacia Senegal and Acacia seyal trees (Osman et al., 1993 and Williams Phillips, et al., 2000).

In addition, Montenegro et al., (2007) determined that the photosensitized RF-mediated degradation of vitamins A, D3, and RF itself in skimmed milk was strongly reduced by the addition of small amounts of lycopene-gum arabic-sucrose microcapsules, prepared by spray-drying. Under these conditions, the bulk properties of the skimmed milk were unmodified. The main photoprotection mechanism of the milk vitamins was the efficient quenching of the 3Rf by the protein moiety of GA. Small contributions (<5%) to the total photoprotection percentage was due to both inner filter effect and 1O2 quenching by the microencapsulated lycopene. 

One remarkable feature of plant gums is the striking uniformity in the structure of gums isolated from different trees of the same type. For example, damson plum trees produce a gum whose properties do not vary from tree to tree. The same has been said by O Sullivan about gum arabic from acacia trees. 

In the twelfth century there appeared in certain Latin works alleged to be translations from the Arabic the theory of the principles of metals namely mercury, which confers metallic properties, and sulfur, which causes the loss of these properties on roasting. Another principle, salt, which imparted refractoriness or fixity in the fire, was added later by the famous popularizer of medical chemistry, Paracelsus (85). 

One of the best known Spanish Plants manufg Explosives and Propellants. It was founded in 1442 while nearly all Southern Spain, including Granada and its fortress Alhambra was in the hands of Arabs. When Granada was reconquered by Spain in 1492, the plant became the property of Royal Spanish Government. The plant was greatly extended in 1908. Its detailed description is given in Refs 1 2 and a briefer description is in Ref 3... 

By the end of the seventeenth century, the old traditional elements from Aristotle had been either abandoned by the new Paracelsian iatrochymists or absorbed under new terminology. Paracelsus tria prima of mercury, SULPHUR, and salt became the new set of elements or principles, each more narrowly focused on a single property than had been the four elements of Aristotle. Yet the tria prima clearly derived from the older tradition. Salt assumed the role of the Aristotelian earth, while sulphur took that of FIRE. The mercury of Paracelsus rather absorbed the characteristics of both AIR and water, becoming the carrier of all spiritual, i.e., volatile qualities of the products of fire analysis. Mercury also carried the basic metallic properties from the mercury/sulphur theory of metals brought to the Latin West from Arabic alchemy. 

The trend in microencapsulation research nowadays is to replace the traditional gelatin + gum arabic system by other biopolymers. The motivation is to design capsules with improved properties, and also to avoid the use of gelatin for health, ethical or religious reasons (de Kruif et al., 2004). For example, gelatin has been replaced by plant proteins in mixtures with gum arabic (Ducel et al., 2004). The physicochemical condi-... 

Weinbreck, F., Wientjes, R.H.W., Nieuwenhuijse, EL, Robijn, G.W., de Kruif, C.G. (2004b). Rheological properties of whey protein/gum arabic coacervates. Journal of Rheology, 48, 1215-1228... 

This deficiency has been overcome by the development of "lipophilic" starches (18,19) starch hydrolyzates incorporating a covalently bound lipophilic species, 1-octenyl succinate. In this manner, a lipophilic polymer is produced which allows for excellent aqueous flavor emulsion stability, good water solubility (40% w/w), excellent retentions of the volatile flavoring material following drying and minimal "extractable" oil in the finished product (9), functional properties only exhibited by gum arabic prior to their development. 

Initial work began with testing various starches for encapsulation properties. Low viscosity, stable starch dextrins were first evaluated versus gum arabic for encapsulation efficiencies. Dispersions of corn and tapioca dextrins were used to encapsulate single fold orange oil. 

The starch dextrins match the viscosity and stability of the gum arabic when placed in solution, however other properties such as emulsifying and emulsion stabilizing properties are poorer in the dextrins. We believe that the emulsifying properties inherent in gum arabic are partially responsible for its encapsulating abilities. 

Starch octenylsuccinates offer excellent emulsifying properties, flavor oil retention and good oxidation resistance versus gum arabic. They can be made on a variety of starch bases, dextrins or fluidities which provide versatility and improved spray-drying costs. Starch octenylsuccinate are low in cost, domestically produced and are not subject to the market fluctuations that gum arabic encounters. 

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