Ices, alginates

Sodium alginate (algin) is one of the most widely used hydrocolloids for ice cream. It is supplied in several viscosity types. The lower viscosity material is recommended in order to prevent thick mixes. It is used at a level of 0.15 to 0.25%. It is added to mix at higher temperatures in order to minimize precipitation by calcium salts present in milk products. Sodium alginate is sensitive to high acidities often developed in some mixes and causes thickening. 

Propylene glycol alginate is not sensitive to mix acidity or calcium ions and is replacing sodium alginate for stabilization of ice cream 0.10 to 0.20% use is recommended. 

Most of the hydrocolloids listed for ice cream may be used in ices and sherbets. Gelatin is used a great deal. However, it makes overrun difficult to control and consequently it is used in conjunction with other hydrocolloids. A 225 Bloom gelatin is used at 0.4 to 0.5%. Sodium alginate is affected by acid and calcium salts and is not often used. Propylene glycol alginate is more resistant in this respect and is used at levels of 0.15 to 0.25%. Carrageenin is used in many blends. 

The hydrocolloids used stabilize this type of icing by their ability to form a gel or a highly viscous solution. Agar-agar, locust bean gum, sodium alginate (combined with a buffer and calcium salt), Irish moss extract, pectin, and karaya gum are hydrocolloids used. The finished icing may contain from 0.1 to 0.5% hydrocolloids. 

W e know of many examples of the effect of impurities of crystallization. In many cases impurities will completely inhibit (2-4) nucleus formation. Reading the literature on this subject impresses one with the frequent occurrence of hydrocolloids as crystal modifiers, particularly where sugar or water is the material being crystallized. The use of gelatin, locust bean gum, or sodium alginate in ice cream is just one example of many practical applications of hydrocolloids in crystal modification. 

Milk fat and milk solids-not-fat (MSNF) are most commonly obtained from cream and condensed skim milk, but may also be obtained from a combination of fluid milk, condensed whole milk, frozen cream, frozen condensed milk, nonfat dry milk, dry whole milk, and butter. Sweeteners used in the mix normally include a combination of liquid or dry sucrose, corn sweetener, high-fructose corn sweetener, and corn syrup solids. Ice cream stabilizers are formulated to contain one or more polysaccharide hydrocolloids, e.g., carboxymethyl cellulose, locust bean gum, carageenin, alginate, and other gums. Ice cream emulsifiers normally contain monoglycerides and diglycerides of palmitic and stearic... 

There are also several water-soluble mixtures of polysaccharides, including those derived from seaweeds and marine animals, such as gum arabic, agar, algin, carrageenan, and chitin. These are hydrophilic. Their suspensions in water can be quite viscous and can readily form gels, and they can form viscous interfacial films around dispersed droplets and bubbles [821], They are used to stabilize suspensions, foams, and emulsions and are used in many different foods and medicines including, for example, ice cream [428,430], See also Ref. [822],... 

Banana/sugar Strawberry/sugar/milk Instant starch Ice cream mix Alginates... 

Polysaccharides from plants, too, can form gels in water. Pectin is used to help gel jams and fruit preserves. Some polysaccharides are used to thicken foods. Alginic acid, extracted from brown algae, is a linear polymer containing many carboxylic acid groups. The sodium salt is soluble in water and is used as a thickener in the preparation of ice cream and other foods. If a sodium alginate solution is mixed with calcium ion, the polysaccharide pre-... 

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