Stabilizers in food and beverages

One of the functions of food additives is to maintain product consistency and also improve mouth-feel. Such as emulsifiers give products a consistent texture and prevent them from separating, while stabilizers and thickeners give smooth uniform texture to deliver on consumer expectation.

Stabilizers are indispensable substances in food items and categorized as food additives. The purpose of emulsifiers & stabilizers is to facilitate the mixing together of ingredients that normally would not mix namely fat and water. Stabilizers are used customarily to improve thickening, mouthfeel, product structure stability water-binding capacity, creamy consistency, and viscosity.

The stabilizers used to enhance the shelf life of food product by preventing them from the microbial attack are called food grade stabilizers.

Stabilizer are substances that can stabilize, retain or intensify an existing colour of a foodstuff and substances that increase the binding capacity of the food to allow the binding of food pieces into reconstituted food.

Xanthan gum is often used in drinks made with citrus and in fruit-flavored drinks to create a satisfactory texture and as a stabilizer for odor and flavor. Because it dissolves quickly and completely at low pH, xanthan gum helps with the suspension of insoluble components.
Stabilizers in food and beverages

Coffee constituents of chlorogenic acid

The chlorogenic acids are ubiquitous in the plant kingdom. Although chlorogenic acids are common in vegetables foodstuffs, the relatively large quantity present in coffee make it an important dietary sources.

Chlorogenic acid and its isomers represent major coffee constituents of phenolic acid. They are family esters of quinic acid with several hydroxycinnamic acids, particularly caffeic, ferulic, p-coumaric acids.

In coffee they are essentially mono- and diesters and by far the prevailing acids. Other esters may occur but generally only in small amounts.

The quality of coffee depends in part on the relative proportion of mono and dichlorogenic acids, The ratio between these two acids is slightly less in robusta than in arabica. An excess of dichlorogenic acids might result in a metallic after-taste in the beverage.

Oral ingestion by man of 200 mg of chlorogenic acid was found to stimulate stomach secretion with enhancement of hydrochloric acid production. Caffeic acid had the same effect, and quinic acid, XII was inactive.
Coffee constituents of chlorogenic acid

Tannins in tea

Tea is a popular beverage throughout the world. It is pleasant and mildly stimulating.

Tannins are a family of astringent compounds called polyphenols. Polyphenols constitute over 48.5% of the total solids in a cup of tea. They’re found in several kinds of plants, including dark sorghum, some apples and yerba mate, a popular South American drink made from the leaves and branches of an evergreen tree.

Tea is often included in the list of tannins-containing foods.   The tea leaves contain varying amounts of tannins: Green teas, which have unfermented leaves, contain the most tannins; black teas including pekoe, which are fermented, contain the fewest.

By definition, tannins are biologically active, that is tannins bond protein, a process that is pH dependent. Most of the phenolic groups in tannins are free. Tannins have a molecular weight between 500 and 3000, and generally are soluble in water.

Tannins are usually divided into two classes: those can be hydrolyzed (react with water) and those that cannot.  The nonhydrolysable tannins found in tea are condensation polymers of catechin.

The occurrence of tannins is reported in unripe fruits such as mango, dates and persimmons. The tannins diminish in amounts as the fruits ripen.

Other food sources of tannins are grapes (condensed tannins, on average 5000 mg/kg of grapes). Grape juice, wines (red wine: 1.2 – 4l4 g/L of wine) and some sorghum grain varieties.
Tannins in tea

Decaffeination of tea: carbon dioxide process

Caffeine is an alkaloid which stimulates the central nervous, muscular and circulatory systems. Too much caffeine in tea are not good for elderly people and caffeine sensitive patients.

Tea is decaffeinated by various methods. Briefly the tea is prewetted and extracted by some organic solvent such as dichloromethane or ethyl acetate. Alternatively, an extraction using supercritical carbon dioxide can be used. Supercritical carbon dioxide is the most widely used solvent for decaffeination of food products. The gas is odorless, tasteless and inert.

When highly pressurized, carbon dioxide assumes a supercritical state and has properties of both a solid and a fluid. At this point, it becomes an efficient solvent for caffeine.

The cp0ressed carbon dioxide is pumped into a chamber with tea. It extracts the caffeine, and the carbon dioxide is separated from the tea and carbon filtered to remove the caffeine.

Carbon dioxide processing leaves no toxic residues. In addition, extraction of the caffeine takes place at room temperature which protects product quality by preventing the breakdown of temperature-sensitive components.

After extraction occurs, the supercritical fluid turns back into a gas, so no solvent residue remains. CO2 decaffeinated teas best retain the original flavors of the teas.

Other advantages of supercritical CO2 as a decaffeination solvent:
*CO2 has suitable critical constant for this application
*CO2 in small amounts is physiological harmless an cause no environmental pollution
*CO2 is cheap, easily available and non flammable
Decaffeination of tea: carbon dioxide process 

Antioxidants in tea

Antioxidants are compounds that help the body to fight harmful free radicals. They accomplish this by circulating throughout the system and neutralizing unpaired electrons, rendering them inactive.

The free radicals occur naturally in the body but excess amount increases the risk of coronary attacks and cancer.

Tea is rich in polyphenolic compounds with antioxidant properties, mainly quercetin and catechin, and these compounds may inhibit oxidative damage to DNA, lipid, carbohydrate and protein.

Oxidative damage is associated with various chronic diseases, including cancer, coronary heart disease, cataract and dementia, and it has been suggested that consumption of tea may lower the risk of chronic disease by improving oxidative/antioxidant balance.

Black tea contains a significant amount of theaflavin compounds that make an important contribution to antioxidant activity, but their effectiveness varies with the individual theaflavin.

The domination of theaflavins are simple theaflavin, theaflavin-3-gallate, theaflavin-3’-gallate, theaflavin-3,3’-gallate which comprises 0.3% - 2% of the dry matter of black tea.

Green tea polyphenols are composed of numerous teas of catechin. Studies show that habitual green tea consumption causes in increase in plasma antioxidant status and a quantitative reduction of free radical-induced markers of lipid peroxidation. 
Antioxidants in tea

High fructose corn syrup in soft drinks

High fructose corn syrup is a corn syrup derived product that has been treated with invertase to converted part of the endogenous glucose to fructose.  It is made by milling corn into corn starch, then processing the corn starch into corn syrup which is almost entirely composed of the sugar known as glucose.

Enzymes are added to corn syrup changing the glucose into fructose. Another name for HFCS is ‘isoglucose’.

High fructose corn syrup contains 42% or 55% fructose - HFCS 42 and HFCS 55 products depending on manufacturing process. HFCS 55 is mostly used in soft drinks contain approximately 55 percent fructose and 45 percent glucose.

It is an extra-sweet inexpensive sweetener used mostly in soft drinks and fruit juices. HFCS performs three functions in beverages:
*Sweet taste
*Contribute mouthfeel
*Intensify overall flavor

Since its debut in the 1970s, it use has grown in popularity within the food industry.

Beverages sweetened with HFCS account for 80% of added sugars in the US diet and account for 80% of the recent increase in calorific intake of the global diet.

Between 1970 and 1990, HFCS consumption increased by more than 100 percent, in large part of the switch from sucrose to HFCS in soft drinks.

Consumption of soft drinks increased by 135 percent between 1977 and 2001, and soft drinks are now the largest source of added sugars in the American diet.
High fructose corn syrup in soft drinks

Methylxanthine in food and beverages

The most common methylxanthine found in food supply are caffeine and theobromine.  Other methylxanthine include theophylline (used in medicines to treat asthmas).

Caffeine was conceived for a wide range of readers interested in the effects on human health, nutrition and physiological function of the methylxanthine beverages and foods – tea, coffee, mate, cola beverages, and coca and chocolate products.

The methylxanthine content of beverages varies considerably. Caffeine is the only methylxanthine in coffee; tea contains caffeine, theobromine and theophylline in decreasing order of concentration, respectively; in cocoa, the predominant methylxanthine is theobromine. Caffeine, which is the only methylxanthine added to soft drinks, present in some soft drinks at concentrations of 15-29 mg per 6 oz. serving.

All methylxanthine have stimulant properties. Research indicates that methylxanthines increase cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) by inhibiting phosphodiesterase and blocking adenosine receptors.
Methylxanthine in food and beverages

Fructose in beverage

Fructose is unique among known sugars in being sweeter than sucrose. Fructose is a six carbon monosaccharide which is abundant in nature. Free fructose is present in honey, dates, figs, apples, grapes and most berries.

Fructose is commercially available as an anhydrous crystalline powder or in its aqueous solution and has been successfully used as a replacement for sucrose as its increase sweetness enables use at lower levels. 

Advances in technology in the 1960s made possible the production of inexpensive high fructose corn syrup from corn starch.

In solution, fructose can exist as four or five isomers, and the relative sweetness of a solution is dependent upon the equilibrium between the sweeter pyranose isomers and the less sweet furanose isomers which is in turn dependent on such condition as pH and temperature.

Soft drink companies found that high fructose sweetener did not alter the taste of the soft drink compared to cane or beet sugar.

Fructose is very soluble and relatively more hygroscopic than sucrose. It has a distinctive clean taste and may be used in synergy with other bulk sweeteners and also some high intensity sweeteners, to improve overall taste profiles.
Fructose in beverage

Sparkling water

Sparkling waters are salt-free, contain no caffeine, no calories and are available with or without added fruit flavor. Sparkling water originates from either mineral or tap water.

The mineral water is taken from an underground well or spring and is still bubbly. Still waters are often carbonated to produce sparking water. Still waters are often carbonated to produce sparkling water.

Perrier, the sparkling water from Languedoc in the south of France, is largely given credit for starting the current bottled water craze in the United States.

Although all soft drinks are predominantly water, sparkling waters are in a class by themselves.

Sparkling water can be healthful alternative to soda and alcoholic beverages but if it loaded with fructose and other sweeteners, it may be no better than soda pop.

Sparkling water shimmering bubbles are said to aid digestion, and its liveliness enhances wine, liqueurs, liquors such as Scotch, rye and gin and fruit and vegetable juices.

Chilled sparkling mineral water is the quintessential aperitif when served in a long-stemmed wineglass with a slice of lemon or lime.

Study published in Journal of Nutrition, found out that drinking of sparkling water brought about significant reductions in the level of LDL cholesterol, as well as a significant increase in levels of HDL cholesterol.

Many sparkling waters now come flavored with fruit essences, which are made from oils obtained from the skin of various fruits.

People suffering from intestinal disorders or ulcers should avoid drinking carbonated water because it may be irritating to the gastrointestinal tract.
Sparkling water