Flavor solubility

Particle-Size Distribution. Particle size, crystal shape, and distribution of vanillin are important and greatly affect parameters such as taste, flavor, solubility, case of dispersion in solvent, flowability of the powder, caking effect, and production of dust. 

Fig. 6.24 Different effects of the volume-averaged mean diameter c/43 of emulsion droplets in the feed liquid on the retention of flavors for different flavor solubilities. The retention of o-limonene ) decreases with the...

The diluent portion also determines the form, or physical appearance, of the flavor, ie, Hquid, powder, or paste. Liquid flavor forms include water-soluble, oil-soluble, and emulsion forms powder flavor forms include plated (including dry solubles), extended, occluded, inclusion complexes, and other encapsulated forms and paste flavor forms include fat, protein, and carbohydrate-based paste. 

Compounded Flavors. Liquid or dry blends of natural or synthetic flavor compounds are called compounded flavors. Most commercial preparations are available as water- and oil-soluble Hquids, spray-dried and plated powders, emulsions, and carbohydrate-, protein-, and fat-based pastes. Compounded flavors are used throughout the food industry in confections, baked goods, snack foods, carbonated beverages, and processed foods (53). 

Margarine and butter contain fat plus water and water-soluble ingredients, eg, salt and milk soHds that impart flavor and color to the product. Generally these products are distributed at refrigerated temperatures to retain their quaHty. Greaseproof packaging, such as polyethylene-coated paperboard, aluminum foil/paper, parchment paper wraps, and polypropylene tubs, is used for butter and margarine (see Dairy substitutes). 

Soybean concentrate production involves the removal of soluble carbohydrates, peptides, phytates, ash, and substances contributing undesirable flavors from defatted flakes after solvent extraction of the oil. Typical concentrate production processes include moist heat treatment to insolubilize proteins, followed by aqueous extraction of soluble constituents aqueous alcohol extraction and dilute aqueous acid extraction at pH 4.5. 

Bl cetyl. Biacetyl [431-03-8] (2,3-butanedione) is a greenish yeUow liquid with a quinone odor. Biacetyl occurs naturally in bay oil and is readily soluble in organic solvents. It is a constituent of many food aromas, eg, butter, and is commonly used to flavor margarine. Flavor-grade biacetyl was available at 20.40/kg in July 1993, and is used as an odorant for coffee, vinegar, tobacco, and in perfumes. 

Benzophenone. Benzophenone [119-61-9] (diphenyl ketone) exists in a stable form as colorless orthorhombic bisphenoidal prisms when crystallized from alcohol or ether. Other labile forms of lower melting point exist. Benzophenone has been identified as a flavor component of wine grapes and has a geranium-like odor. It is soluble in most organic solvents, and is insoluble in water. 

Liquid food ingredients encapsulated are typically oil-soluble flavors, spices (see Flavors and spices), and vitamins (qv). Even food oils and fats are encapsulated (63). These core materials normally are encapsulated with a water-soluble shell material appHed by spray drying from water, but fat shell formulations are used occasionally. Preferred water-soluble shell materials are gum arabic, modified starch, or blends of these polymers with maltodextrins. Vitamins are encapsulated with 2ero bloom strength gelatin by spray drying. 

Alitame (trade name Adame) is a water-soluble, crystalline powder of high sweetness potency (2000X, 10% sucrose solution sweetness equivalence). The sweet taste is clean, and the time—intensity profile is similar to that of aspartame. Because it is a stericaHy hindered amide rather than an ester, ahtame is expected to be more stable than aspartame. At pH 2 to 4, the half-life of aUtame in solution is reported to be twice that of aspartame. The main decomposition pathways (Fig. 6) include conversion to the unsweet P-aspartic isomer (17) and hydrolysis to aspartic acid and alanine amide (96). No cyclization to diketopiperazine or hydrolysis of the alanine amide bond has been reported. AUtame-sweetened beverages, particularly colas, that have a pH below 4.0 can develop an off-flavor which can be avoided or minimized by the addition of edetic acid (EDTA) [60-00-4] (97). 

Most of the thiamine sold worldwide is used for dietary supplements. Primary market areas include the following appHcations addition to feed formulations, eg, poultry, pigs, catde, and fish (see Feeds and feed additives) fortification of refined foods, eg, flours, rice, and cereal products and incorporation into multivitamins. Small amounts are used in medicine to treat deficiency diseases and other conditions, in agriculture as an additive to ferti1i2ers (qv), and in foods as flavorings. Generally for dry formulations, the less soluble, nonhygroscopic nitrate is preferred. Only the hydrochloride can be used for intravenous purposes. Coated thiamine is used where flavor is a factor. 

Agricultural Use. Citric acid and its ammonium salts are used to form soluble chelates of iron, copper, magnesium, manganese, and zinc micronutrients in Hquid fertilizers (97—103). Citric acid and citrate salts are used in animal feeds to form soluble, easily digestible chelates of essential metal nutrients, enhance feed flavor to increase food uptake, control gastric pH and improve feed efficiency. 

The long fermenting process converts several glucosides into glucose, vanillin, and other complex aromatic flavors. The vanilla beans can be further processed by extracting soluble compounds in ethanol and water mixtures, resulting in vanilla extract. 

Sodium benzoate is used as a broad-spectrum antimicrobial, inhibiting bacteria, molds, and yeasts. The high acid content of the soft drink is necessary for the preservative action. Sodium citrate buffers the acids, so the pH stays low (acidic). It also emulsifies any fats or fat-soluble compounds in the flavorings, keeping them in solution. 

If an aqueous solution of a compound is shaken with another liquid that is immiscible (mutually insoluble) with water, some of the compound may dissolve in the other solvent. For example, molecular iodine, I>, is very slightly soluble in water but is highly soluble in tetrachloromethane, CC14, which is immiscible with water. When tetrachloromethane is added to water containing iodine, most of the iodine dissolves in the CC14. The solute is said to partition itself between the two solvents. Solvent extraction is used to obtain plant flavors and aromas from aqueous slurries of the plant that have been crushed in a blender. 

In some cases, the solids themselves are subjected to extraction by a solvent. For example, in one process used to decaffeinate coffee, the coffee beans are mixed with activated charcoal and a high-pressure stream of supercritical carbon dioxide (carbon dioxide at high pressure and above its critical temperature) is passed over them at approximately 90°C. A supercritical solvent is a highly mobile fluid with a very low viscosity. The carbon dioxide removes the soluble caffeine preferentially without extracting the flavoring agents and evaporates without leaving a harmful residue. 

---