Part II Ingredient Categories

Abstract

Acidulants are acids used in processed foods for a variety of functions that enhance the food. Acids are used as flavoring agents, preservatives in microbial control, chelating agents, buffers, gelling and coagulating agents, and in many other ways.

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Acidulants

Acidulants are acids used in processed foods for a variety of functions that enhance the food. Acids are used as flavoring agents, preservatives in microbial control, chelating agents, buffers, gelling and coagulating agents, and in many other ways. Examples of these functions are:

• Flavoring agent—Contributes and enhances flavor in carbonated beverages, fruit drinks, and desserts.

• Preservative—An acid medium restricts the growth of spoilage organisms in mayonnaise and tomato sauce, and retards the activity of enzymes involved in discoloration in fruits.

• Chelating agent—Aids in binding metals that can cause oxidation in fats and oils, and discoloration in canned shrimp.

• Buffer—Maintains and controls acidity during processing, and maintains acidity within a given range in prepared desserts.

• Gelling agent—Controls the gelling mechanism of algin and pectin gels such as desserts and jams.

• Coagulating agent—Reduction of pH results in coagulation of milk protein which is used in the preparation of direct acidified cheese and desserts.

Acidulant selection depends upon the application or processed food. The properties to consider are flavor profile, pH, solubility rate, solubility, and hygroscopicity. Flavor profile refers to the perceived sharpness or blandness contributed by the acid. Tartaric and citric acids provide a sharp taste as compared to lactic acid, which provides a blander taste. Fumaric acid and tartaric acid provide the greatest degree of sourness. Comparing acids relative to similarity of taste to citric acid, the relative equivalents are citric acid: 100; fumaric acid: 55; tartaric acid: 70; malic acid: 75; succinic acid: 87; lactic acid: 107; and glucono-delta-lactone: 310. The acids provide different pHs at similar concentrations, falling generally in the range of pH 2–3 at 1% concentration. The solubility rate determines how rapidly the acid dissolves and contributes toward the flavor profile. In a beverage powder dissolved in cold water, rapid solubility is required, so perhaps citric acid would be used. The solubility of the acid refers to the quantity in solution. Cream of tartar and fumaric acid have low solubilities, which makes them suitable for bakery applications in controlling leavening systems. Phosphoric acid, a liquid, is miscible with water and used in beverage syrups. Hygroscopic acids will absorb moisture, and ­hygroscopicity needs to be considered when the application is dry mixes. If hygroscopic acids, such as citric or tartaric acids, are used in dry mixes, proper packaging is essential. Alternative less hygroscopic acids are adipic and fumaric acid.

Table 1 illustrates the properties of the principal acids used in the food industry.

Table 1 Comparative Acid Chart

Antioxidants

Antioxidants are chemical compounds that provide stability to fats and oils by delaying oxidation (which involves the loss of electrons and the gain of oxygen). The oxidation of fats and oils is believed to occur as a series of chain reactions in which oxygen from the air is added to the free fat radical. The fat molecule loses a hydrogen atom and becomes an unstable free radical with a high affinity for oxygen. Oxygen is added and the fat molecule, to complete its electron structure, reacts with another fat molecule and removes a hydrogen atom. This produces another free radical and results in a chain reaction. The antioxidant functions by replacing the fat molecule as the hydrogen atom donor in order to complete the electron structure of the free radical, thus terminating the chain reaction. Thus oxidative rancidity, which results in off-flavors and odors, is retarded until the antioxidant supply is used.

The most commonly used antioxidant formulations contain combinations of BHA (butylated hydroxyanisole), BHT (butylated hydroxytoluene), and propyl gallate. These formulations usually contain a chelating agent (reacts with metal to form a complex and thus prevents the metal from acting as a catalyst in oxidative reactions), of which citric acid is the most common. Natural antioxidants such as the tocopherols and guaiac gum usually lack the potency of BHA, BHT, and propyl gallate combinations.

Antioxidants are effective at low concentrations, that is, 0.02% or less, based on the fat or oil content of the food. Examples of applications are:

• Rendered animal fat, such as lard

• Vegetable oils, such as cottonseed oil and corn oil

• Food products of high fat content, such as doughnuts and potato chips

• Food products of low fat content, such as cereals and dehydrated potatoes

Antioxidants should be added to fats and oils before oxidation has started in order to be effective. The antioxidant cannot reverse the oxidation process nor regenerate a product that has become rancid. The oxidation process is accelerated by heat, light, moisture, metals, and other factors.

Antioxidants include trihydroxybutyrophenone (THBP), dilauryl thiodipropionate (DLTDP), nordihydroguaiaretic acid (NDGA), guaiac gum, thiodipropionic acid, tocopherols, lecithin, sodium erythorbate, ascorbic acid, and ascorbyl palmitate.

Chelating Agents (Sequestrants)

Chelation is an equilibrium reaction between a chelating (complexing) agent and a metal ion which forms a complex. Trace metal ions in foods can produce undesirable effects such as discoloration, turbidity, and oxidation. The chelating agents can form a complex with the unwanted trace metals, thus blocking the reactive sites of the metal ions and rendering them inactive. The complex formed is termed a chelate, that is, metal  +  chelating agent  =  metal complex.

An equilibrium constant K defines the ratio of chelated metal to unchelated metal. The log  K is the stability constant, measuring the affinity of the complexing agent for the metal ion. A high K value indicates a high affinity of the complexing agent for the metal ion and thus a low value for free metal ion concentration. Stability constants for some metal ions are shown in Table 2.

Table 2 Metal Ion Stability Constants

The most problematic metal ions in foods are iron and copper. In a system containing several metal ions, the ones with the highest ­stability constants will be chelated first, followed in order of highest stability constant until the chelating agent is used.

Chelating agents are used to control the reactions of trace metals in foods to principally prevent discoloration, such as that occurs in potatoes when iron reacts with phenolic compounds in the presence of oxygen. They are also used with antioxidants to complex trace metals, thus preventing the metal from acting as a catalyst in oxidative reactions. Application examples are the use of:

• Phosphates in soft drinks to chelate heavy metal ions that interfere with carbonation.

• EDTA in mayonnaise to eliminate the oxidative activities of trace metals and protect flavor.

• Sodium acid pyrophosphate to prevent discoloration in potatoes.

• Sodium hexametaphosphate to sequester calcium ions and permit the solubilization of alginates.

Examples of chelating agents include calcium disodium EDTA, disodium dihydrogen EDTA, tetrasodium pyrophosphate, citric acid, monoisopropyl citrate, phosphoric acid, and monoglyceride phosphate.

Colors

Colors are usually designated artificial or natural, which indicates that they are, respectively, synthetically manufactured or obtained from natural sources. Synthetic color additives “certified” by the Food and Drug Administration are designated FD&C (Food, Drug, and Cosmetic) and are traditionally termed primary colors. These colors are shades of red, yellow, blue, and green. Secondary colors are blends of certified primary colors, with or without diluents. Table 3 lists the physical and chemical properties of the certified food colors.

Table 3 Physical and Chemical Properties of Certified Food Colors

Those acceptable food colors not designated “certified” are designated “approved” and consist of natural organic and synthetic inorganic colorants used in certain applications (see Table 4). Colors are available in powders, liquids, granules, pastes, and other forms. Colorant determination includes desired hue, water solubility, and stability. The following groupings are used to illustrate different color groups.

Table 4 Physical and Chemical Properties of Some Noncertified Colors

Artificial Coloring

Water-soluble colors are designated as FD&C, followed by the color name and number designation, for example, FD&C Blue #2. They have a corresponding common name, for example, indigotine. The colors vary in hue, solubility, and other properties, which relates to the intended application. The water-soluble colors include FD&C Blue #1, Blue #2, Green #3, Red #40, Yellow #5, and Yellow #6.

Water-insoluble colors are termed FD&C aluminum lakes. Lakes are prepared by the absorption of a certified dye on an insoluble substrate, aluminum hydroxide, and as such include the standard colors. Lakes are used to color dry ingredients, increase stability, and reduce color migration. Lakes can be used to color foods with a high oil or fat content, in dry mixes and coated candies, and for other purposes.

Natural Coloring

Natural colors are usually extracted from botanical sources and often contain several pigments and, as such, are not used as direct replacements for FD&C colors. The colors have low tinctorial strength due to a low quantity of pigment present and thus are used at higher levels than FD&C colors. These colors generally have poor stability in that their color and rate of degradation are affected by pH, temperature, and other conditions. Some natural colorings are:

• Annatto—The pigment bixin found in the coating of the annatto seed. The color hue ranges from yellow to reddish-orange.

• Turmeric—Contains curcumin obtained from turmeric root. The color hue varies from greenish-yellow to yellow-orange.

• Paprika—Produces a red to red-orange color.

• Beet—Produced from red beets and has a deep reddish-purple color.

Corn Sweeteners

Corn sweeteners are the products made by using mild conversion techniques to produce starch hydrolysates, that is, dextrin, maltodextrin, and corn-syrup solids. These carbohydrates vary according to sugar composition, which accounts for their differences in properties. They are classified in terms of dextrose equivalent (DE), a standard that expresses the level of reducing sugar calculated as dextrose (see Table 5). Complete conversion of cornstarch yields dextrose, also termed corn sugar, which has a DE of 92. When the reaction is stopped at the intermediate stage, corn syrup, consisting of dextrose, maltose, and polysaccharides, is obtained. It can be manufactured to have the desired DE based on desired properties. A common distribution is 28–38 DE (low conversion) to 58–68 DE (high conversion). Partial hydrolysis of cornstarch commercially produces maltodextrins of DE ranging from 13 to 22 and dextrin, with a DE range of 7–12. In high-fructose corn syrup, a fraction of the dextrose has been converted enzymatically to fructose, thus making a sweeter syrup.

Table 5 Comparison of Properties Relative to Dextrose Equivalent (DE)

Emulsifiers

Emulsifiers are products that function to reduce the surface tension between two immiscible phases at their interface, allowing them to become miscible. The interface can be between two liquids, a liquid and a gas, or a liquid and a solid. Most emulsions involve water and oil or fat as the two immiscible phases, one being dispersed as finite globules in the other. The liquid as globules is referred to as the dispersed or internal phase, while the medium in which they are suspended is the continuous or external phase. There are two types of emulsions depending on the composition of the phases. In an oil-in-water emulsion such as milk and mayonnaise, the water is the external phase and the oil is the internal phase. In a water-in-oil emulsion such as butter, the oil is the external phase and the water is the internal phase. By use of the proper emulsifier, the two phases will mix and separation is prevented or delayed.

The emulsifier consists of a hydrocarbon chain which has affinity for fats and oils (lipophilic group) and a polar group which is attracted to water or aqueous solutions (hydrophilic group). The emulsifier tends to concentrate at the interface between two immiscible liquids, with the hydrophilic portion in the water and the lipophilic portion in the oil. In such fashion, the surface properties are altered by the orientation of the emulsifiers at the interface which reduces the resistance of the two substances to combine. They are frequently used as blends for obtaining the most stable emulsion system. Emulsifiers have the following major functions:

• Complexing—Reaction with starch in bakery products which retards the crystallization of the starch, thus retarding the firming of the crumb which is associated with staling.

• Dispersing—The reduction of interfacial tension which creates an intimate mixture of two liquids that normally are immiscible, an example being oil-in-water emulsions such as salad dressing.

• Crystallization control—Control of crystallization in sugar and fat systems, i.e., chocolate, where it allows for brighter initial gloss and prevention of solidified fat on the surface.

• Wetting—Allows the surface to be more attracted to water, such as powders, i.e., coffee whitener, in which the addition of surfactant aids the dispersion of the powder in the liquid without lumping on the surface.

• Lubricating—Functions as a lubricant, such as in caramels, by reducing their tendency to stick to cutting knives, wrappers, and teeth.

Emulsifiers are also classified according to their solubility, being hydrophilic (water-loving) or lipophilic (oil-loving). The HLB, or hydrophilic/lipophilic balance, is a measure of the emulsifier’s affinity to oil or water. The HLB range is 0–20, where 0 indicates completely lipophilic and 20 indicates completely hydrophilic. The behavior of emulsifiers in water according to the HLB range is shown in Table 6.

Table 6 Behavior of Emulsifiers in Water According to HLB Range

Table 7 lists the FDA names of food-grade emulsifiers and the Title 21 Code of Federal Regulations reference number for each.

Table 7 FDA Names of Food-Grade Emulsifiers and the Title 21 Code of Federal Regulations References

Fats and Oils

Fats and oils belong to a group of substances classified as lipids which consist of the higher fatty acids and compounds associated with them. Lipids are characterized by their solubility in fat solvents, their insolubility­ in water, and their greasy feel. Fats and oils are of similar chemical structure but differ physically in that at ordinary temperatures, fats are solids and oils are liquids. They are complex mixtures of predominantly mixed triglycerides, which are the compounds formed by ­combining one molecule of glycerol with three molecules of fatty acids. The fatty acids may be the same, two different fatty acids, or all different. Fatty acids are composed of a chain of carbon with hydrogen atoms, terminating in a carboxyl group. Fatty acids contain carbon chain lengths ranging from 4 to 24 and are identified according to the number of carbon atoms and whether they are saturated or unsaturated. Saturated fatty acids contain only single-bond carbon linkages and cannot accept additional hydrogen; unsaturated fatty acids have one or more double bonds and thus fewer hydrogen atoms and can accept hydrogen. Mono-unsaturated indicates that hydrogen can be accepted at one double-bond site; polyunsaturated indicates that hydrogen can be accepted at more than one double-bond site. The most highly unsaturated fats are oils, while fats of low unsaturation tend to be solids at room temperature. Hydrogenation (chemical addition of hydrogen to the double bond of unsaturated fatty acids) of a fat makes it firmer and more plastic, raises the melting point, and slows the development of rancidity by reducing the rate of reaction with oxygen. These fats are termed hydrogenated or partially hydrogenated oils. Fats and oils are composed of varying percentages of fatty acids which account for their respective properties. Some useful properties to consider in determining a suitable fat or oil include:

• Iodine value—An expression of the degree of unsaturation, which can serve as a guide in evaluating fat stability.

• Melting point—The temperature at which a solid changes to a liquid when heated.

• Solid fat index—A number indicating the proportion of solid to liquid present in the fat at a given temperature, which will reflect the consistency.

Fats and oils are used by themselves or as components of a food. Some examples of nomenclature are:

• Shortenings—Usually solid fats instead of oils used in baked goods to impart tenderness, soft crumb, etc.

• Spreads—Usually butter or margarine, which contains 80% or more fat.

• Salad oils—Oils which include olive, corn, cottonseed, soybean, sunflower.

• Cooking fat—Any edible fat or oil.

• Frying fat—A bland-flavored fat or oil of high smoking temperature to allow for heating to 400°F without smoking.

• Confectionary fat—A fat that is hard at room temperature and soft at body temperature, such as hydrogenated coconut oil or cacao butter.

Table 8 lists fats and oils with their principal component fatty acids.

Table 8 Fats and Oils and Their Principal Component Fatty Acids

Table 9 Comparative Properties of Gums

Table 10 Relative Properties of Gelling Gums

Table 11 Preservatives

Table 12 Spices and Other Natural Seasonings and Flavorings

Table 13 Nutritive Sweeteners Sweetness Relative to Sucrose

Table 14 Polyols Sweetness Relative to Sucrose

Table 15 High-Intensity Sweetness Relative to Sucrose

Table 16 Vitamin Functions and Sources

Flavors

Flavors are classified into the major groups of spices, natural flavors, and artificial flavors. A spice is an aromatic vegetable substance in a whole, broken, or ground form which is used as a seasoning. Natural flavors are flavor constituents derived from plant or animal sources. Artificial flavors are flavorings containing all or some portion of nonnatural materials.

Materials that can be used for flavorings can be grouped as follows: spices and herbs; essential oils and their extracts; fruits and fruit juices; and aliphatic, aromatic, and terpene compounds. Spices and herbs consist of dried plant products that exhibit flavor and aroma. They are derived from true aromatic vegetable substances from which the volatile and flavoring principles have not been removed. Essential oils and their extracts are odorous oils obtained from plant material and have the major odor that is characteristic of that material. Most have poor water solubility and most contain terpenes (hydrocarbons of formula C₁₀H₁₆ and their oxygenated derivatives C₁₀H₁₆O or C₁₀H₁₈O) which contribute to the poor water solubility as well as possibly contributing to the off-flavor. Examples are essential oils of bitter almond, anise, and clove. Terpeneless oils are extensions of concentrated essential oils in which the unwanted terpenes are removed. These oils are usually more concentrated and of increased stability and water solubility. Common oils in the terpeneless form are citrus oil, spearmint, and peppermint. Fruit and fruit juices are natural flavorings obtained from fruits. Whole, crushed, or pureed fruit may be used, but, more commonly, the juice or concentrate is used. Fruit extracts are made by extraction with a water–alcohol mixture. Aliphatic, aromatic, and terpene compounds refer to synthetic chemicals and isolates from natural materials. This classification encompasses the largest group of flavoring materials.

Flavors can be quite complex and the number of available flavors is extensive. Flavor is that property of a substance that causes a sensation of taste. Four basic tastes are perceived by taste buds on the tongue: sweet, salty, sour, and bitter. The flavors used are natural, artificial, or combinations and exist in liquid or dry form. General flavor types available include fruit, dairy, meat, vegetable, beverage, and liquor.

Flour

Flour, also referred to as white flour, wheat flour, and plain flour, is the food prepared by grinding and bolting cleaned wheat other than durum wheat and red durum wheat (Code of Federal Regulations). Flour from other sources is available, identified according to its grain source. The properties of wheat flour vary according to the type of wheat, milling procedures, and treatment applied after milling.

Flour milling involves the separation of the endosperm, which is about 83% of the kernel, from other parts of the kernel, that is, bran and germ. The processing involves tempering, grinding, and sifting the large chunks of endosperm or “middlings” to yield the flour which, in the USA, will represent about 72% of the wheat kernel. By processing, size classification is achieved as flour streams. The streams include:

• 1. Straight flour—All the flour that can be milled from a wheat blend, or 72% of the wheat kernel which equates to 100% separation.

• 2. Long patent flour—90–95% separation.

• 3. Medium patent flour—80–90% separation.

• 4. Short patent flour—70–80% separation.

• 5. Short family or first patent flour—60–70% separation.

• 6. Extra short or fancy patent flour—40–60% separation.

• 7. Clears—Portion of straight flour remaining after removal of ­patent streams.

Flour properties depend upon the type of wheat, which is classified as hard or soft. Hard wheats are high in protein and the resulting flours have a high protein content and form a tenacious, elastic gluten with good gas-retaining properties and high water absorption capacity which makes it suitable for yeast-leavened bread. Soft wheats are low in protein and the resulting flour has poor gas-retaining properties and low water absorption capacity which makes it suitable for chemically leavened cakes and pastries.

The protein content of the flour is important because it forms the protein complex termed gluten when water and flour are kneaded together. The gluten formed accounts for the mixing and dough-handling characteristics as well as in the formation of the framework of the baked product.

Different flours are used for different purposes. Some of these include:

• Bread flour, which generally contains in excess of 10.5% protein and is obtained from straight or long patent flours, has high absorption and good mixing tolerance.

• Cake flour, which generally contains less than 10% protein and is generally short patent flours, is low in absorption, and has short mixing time and tolerance.

• All-purpose (family) flour, which is intermediate between bread and cake flour.

• Pastry flour, which is obtained from soft wheat and can be straight or clear flour grades because color is not an essential requirement.

• Cracker flour, which generally contains 9–10.5% protein obtained from long patent or straight flours, is of low absorption, and has short mixing requirements.

Flours can be modified by various treatments to alter characteristics such as color, nutritional value, and baking qualities. Some of these modified flours include:

• Enriched flour—Flour that has been enriched by the inclusion of vitamins and minerals.

• Bromated flour—Potassium bromate has been added for improvement of baking qualities.

• Phosphated flour—Monocalcium phosphate has been added for improvement of baking qualities.

• Bleached flour—Flour in which the yellow carotenoid pigment has been converted to a nearly colorless product.

Other specific grain flours are obtained, with the term flour referring to that degree of grinding and sifting which results in a fine, powdery substance. The grain flours in Exhibit 1 are designated according to the grain from which they are obtained and include corn, rye, and durum flours.

Exhibit 1 Cereal Flours Listed in the Code of Federal Regulations Part 137

Gums

Gums are classified by source according to the following principal groupings: plant exudates, which include arabic, tragacanth, karaya, ghatti; seaweed extracts, which include agar, alginates, carrageenan, furcelleran; plant seed gums, which include guar, locust bean, tara, tamarind, psyllium, quince; plant extracts, which include pectin and arabinogalactan; fermentation gums, which include xanthan gum, gellan gum, and dextran; and cellulose derivatives, which include carboxymethyl cellulose, hydroxypropylmethyl cellulose, microcrystalline cellulose. Gum derivatives include propylene glycol alginate and low-methoxy pectin. Galactomannans are polysaccharides consisting of a mannose backbone with galactose side groups. Included in this family are guar gum, tara gum, locust bean gum with respective mannose:galactose ratios 2:1, 3:1, 4:1, with the higher amounts of galactose resulting in more solubility. Starches and gelatin function as water-control agents but are not included in this grouping.

The selection of a gum is based on the desired function and food application. By thickening or gelling the water, gums perform numerous roles such as stabilizers, film formers, binders, suspending agents, whipping agents, coating agents, and crystallization inhibitors. The gums perform these functions by themselves or in combination with other gums. Food properties considered in selecting a gum include pH, shelf stability, ingredient compatibility, texture, processing requirements, and ultimate consumer method of preparation. The differentiating properties of gums include viscosity, compatibility, pH stability, gel-forming capabilities, temperature stability, flow properties, and solubility. Within the same family of gums, there may be differences relative to salt type which will have an effect on its functional characteristics, that is, solubility, dispersibility, gel-forming capabilities, flow properties, and stability. Tables 9 and 10 list, respectively, comparative and relative properties of gums.

Preservatives

Preservatives are antimicrobial agents. The preservatives most widely used are the benzoates (sodium benzoate), sorbates (sorbic acid and potassium sorbate), and the propionates (sodium or calcium propionates), which are organic acids or their salts (see Table 11). The activity of preservatives is due to the undissociated form of the molecule and thus pH is a major factor in their effectiveness. Increasing the acidity of foods is a method of controlling the growth of microorganisms. The survival and proliferation of microorganisms depend in part upon the pH of the food. Foods with a pH below 4.6 are considered acidic, and many bacteria will not proliferate in acidic foods. Acidulants are used to reduce the pH and thus provide a means of controlling microorganism growth. Acidulants used include acetic acid, adipic acid, citric acid, fumaric acid, lactic acid, and phosphoric acid. Greater effectiveness is achieved in acidic systems. Sorbic acid and potassium sorbate have the best activity up to pH 6.5, calcium and sodium propionate up to pH 5.0, and sodium benzoate up to pH 4.5.

Sorbic acid and potassium sorbate are effective against yeast and mold inhibition with little activity against bacteria. Common uses are in cheese, sausage, and baked goods not including yeast-raised goods. Sorbic acid has low solubility in water which increases with increasing temperature, while potassium sorbate is readily soluble in water. Potassium sorbate has the same antimycotic properties as sorbic acid and on an equivalent weight basis has 74% of the activity of sorbic acid. Thus, higher concentrations are required to obtain the same yeast and mold-inhibiting effects (four parts potassium sorbate equal three parts sorbic acid).

Calcium and sodium propionate are effective against molds and have slight antibacterial action and little action on yeasts. Application areas include baked goods and processed cheese. Because they have little action against yeasts, they can be used in yeast-baked goods and are the most common preservative in baked goods.

Sodium benzoate is effective against yeasts and slightly effective against bacteria and molds. The most effective range is pH 2.5–4.0 with a maximum pH of 4.5. It is used in acidulated beverages, jams, jellies, and relishes.

Parabens, which are esters of para-hydroxybenzoic acid, are related to benzoic acid but are effective over a wider pH range. They are active against yeasts and molds and are used in baked goods and beverages.

Spices

Spices consist of dried plant products that exhibit flavor and aroma. Spices are obtained from vegetable substances from which none of the volatile or other flavoring substances have been removed. Spices are grouped into (a) tropical spices such as pepper and cloves; (b) herbs, such as sage and rosemary; (c) spicy seeds such as mustard and anise; and (d) dehydrated aromatic vegetables such as onion and garlic.

Spices in the ground form have an increased surface area and consequently the oil glands are ruptured, causing the evaporation of the essential oil and loss of aroma. Spice flavor is also obtained by use of an extract or essential oil which carries the spice aroma in a concentrated form. These oils are volatile and as such do not contain the nonvolatile constituents. The compound containing both the essential oil and the nonvolatile constituents is commercially known as oleoresins, which contain all the odorous and flavor principles of the spice. Oleoresins offer flavor uniformity, stability, freedom from bacteria, and flavor concentration.

Spices are used predominantly in prepared meats, luncheon meats, sauces, salads, soups, and dressings. Other important users are bakers, pickle packers, condiment manufacturers, and the canning industry.

A list of spices and other natural seasonings and flavorings, found in Title 21, Section 182.10, of the Code of Federal Regulations, is in Table 12.

Starch

Starch, consisting of repeating glucose units, is separated into the polysaccharides amylose and amylopectin. Amylose consists of straight chains containing 200–2,100 glucose units, while amylopectin consists of branched chains containing 20–25 glucose units each. A visible difference is that amylose is more soluble and less viscous than amylopectin and facilitates gel formation. Starches vary in their amylose content.

Waxy starches, so termed because the cut endosperm resembles hard, opaque wax, contain mostly amylopectin, while ordinary cornstarch consists of about 24% amylose and 76% amylopectin. The waxy starches form thick, clear pastes but gel only at high concentrations such as 30%, while 4–5% cornstarch will form a gel. The paste viscosity of the waxy maize starch remains the same hot or cold. High-amylose starches contain 50–70% amylose and have unique properties for functioning as film formers, oxygen and fat barriers, quick-setting stable gels, and binders.

Starch is not soluble in cold water, but forms a suspension. Upon heating the suspension to the gelatinization temperature (60–70°C), the starch granules suddenly swell, the opaque suspension slowly becomes translucent upon continued heating, and the viscosity increases to the thickness of a boiled starch paste. Most starches require heating to 90°C in order to obtain a firm gel upon cooling, when the viscosity increases and may form a gel depending on the type of starch. During storage of a starch paste or gel, the molecules become less soluble and tend to aggregate and partially crystallize; the change is termed retrogradation, which is the opposite of gelatinization. The starch gel shrinks and some of the liquid separates from the gel. Retrogradation does not occur in waxy starches because they do not contain amylose.

Starches can be modified (they are then termed modified starches) by chemical modification or cross-linking, to provide desired properties not found in natural starch. By the production of cross-links or bridges from one starch molecule to another, starch can be made more resistant to hydrolysis, thus preventing the loss of viscosity. The resistance of starch to shear or mixing is directly proportional to the degree of cross-linking. Other properties obtained include viscosity control, freeze–thaw stability, heat resistance, and acid resistance. These starches find application in sauces, gravies, pie filling, frozen foods, and other products where specific properties are required.

Pregelantinized starch is a starch processed to swell to some degree in cold water unlike regular starch, which requires heating. The most common method involves heating a starch paste to its gelatinization temperature, drying on a drum dryer, and grinding the dried starch to a powder. Upon reconstitution with water, the pregelatinized starch has less thickening power and tendency to gel than pastes of the parent starch. This starch is used in applications requiring more rapid hydration or room temperature preparation, such as instant desserts, puddings, and soups. Based on abundance and cost, cornstarch is the most commonly used. Other available starches include grain sorghum, rice, wheat, potato, tapioca, arrowroot, and waxy varieties.

Sweeteners

Sweeteners can be classified as natural or artificial. The natural sweeteners are carbohydrates consisting of molecules of carbon, hydrogen, and oxygen. The simplest form of carbohydrate is the monosaccharide or simple sugar and includes glucose (dextrose), fructose (levulose), and galactose, which are six-carbon (hexose) sugars.

The combination of two monosaccharides forms a disaccharide sugar, which can also be formed by the breakdown of longer-chain carbohydrates termed polysaccharides. The following combinations of monosaccharides form the respective disaccharides: glucose  +  frucose  =  sucrose; glucose  +  galactose  =  lactose; glucose  +  glucose  =  maltose.

A trisaccharide consists of three monosaccharides, such as raffinose which consists of galactose, glucose, and fructose. A tetrasaccharide such as stachyose consists of four monosaccharides. These more complicated sugars are not digestible so they are not used as sweeteners. A polysaccharide is a longer-chained carbohydrate which exists in digestible and nondigestible forms. The digestible forms are starch, a polymer of glucose units from which corn sweeteners are obtained, and glycogen, a polymer of glucose which is the carbohydrate reserve of animals. The nondigestible form includes cellulose, lignin, and gums such as pectin and algin.

Polyhydric alcohols (polyols) in foods consist of glycerine, sorbitol, mannitol, propylene glycol, and xylitol. When used at low levels, the taste of the polyols is of minor consequence; but when used as a major ingredient, such as in sugarless chewing gum, the polyol is the major source of sweetness.

Sucrose is the most widely used natural sweetener and is usually the reference relative to sweetness, taste profile, and cost. Corn sweeteners, fructose, and high intensity sweeteners are other widely used sweeteners.

Sweeteners are also grouped as nutritive and non-nutritive. Nutritive sweeteners include sucrose, fructose, dextrose, lactose, maltose, honey, high fructose corn syrups, and polyols. Non-nutritive sweeteners (artificial sweeteners) include saccharine, aspartame, acesulfame-K, sucralose, neotame, and rebaudioside A.

The relative sweetness of sweeteners relative to sucrose can vary according to concentration, temperature, etc. (Table 13).

Polyols (polyhydric alcohols, sugar alcohols) are produced by ­hydrogenating the corresponding reducing sugars, for example, sorbitol – hydrogenated from glucose. They provide the bulk and texture of sucrose but have less kilocalories/gram. Polyols include sorbitol, mannitol, xylitol, erythritol, lacticol, maltitol, and isomalt (Table 14).

High-Intensity Sweeteners

High-intensity sweeteners are products intended to imitate the taste of sucrose and function as non-nutritive replacements; they provide basically 0 cal. Saccharin, discovered in 1878, has the longest history of food use.

The properties of high intensity sweeteners vary according to source, relative sucrose sweetness, taste profile, solubility, stability to temperature and pH, synergies, and applications. These sweeteners are used singly or in combination to maximize the beneficial properties of each (Table 15).

Vitamins

Vitamins are organic compounds that are essential for normal body growth and maintenance. They are classified into groups: fat-soluble vitamins – vitamins A, D, E, and K; and water-soluble vitamins – vitamins B and C. Vitamins are measured in very low concentrations, such as 1–100 mg. Through biochemical action, they perform various functions in such processes as cell growth, normal digestion, manufacture of red blood cells, and absorption of calcium and phosphorus. Inadequate vitamin intake can be the result of food deficiency, increased vitamin requirements, and increased vitamin loss. The vitamins of determined importance include A (retinol), B₁ (thiamine), B₂ (riboflavin), B₅ (pantothenic acid), B₆ (pyridoxine), B₁₂ (cyanocobalamin), C (ascorbic acid), D₂ (calciferol), E (tocopherol), K, niacin, folic acid, and biotin.

Table 16 describes the functions and provides sources for fat- and water-soluble vitamins.