FACULTY of ENGINEERING FOOD ENGINEERING FOOD ADDITIVE
ADDITIVES IN MARGARINE
SUBMITTED by ZEYNEP YILMAZ SUBMITTED to HUSEYIN BOZKURT DATE 17.05.2007 REFERENCES ANDERSEN, A.J.C. MARGARINE, 1954
FOOD ADDITIVES
Food additives play a vital role in today’s bountiful and nutritious food supply. They allow our growing urban population to enjoy a variety of safe, wholesome and tasty foods year-round. And, they make possible an array of convenience foods without the inconvenience of daily shopping.
Although salt, baking soda, vanilla and yeast are commonly used in foods, today many people tend to think of any additives added to foods as complex chemical compounds. All food additives are carefully regulated by federal authorities and various international organizations to ensure that foods are safe to eat and are accurately labeled. The purpose of this brochure is to provide helpful background information about food additives, why they are used in foods, and how regulations govern their safe use in the food supply.
ADDITIVES
Antioxidants
Antioxidants prevent fats and oils from going rancid due to oxidation of the unsaturated fatty acid radicals in the triglycerides of which fat is composed. Antioxidants which occur naturally in fats tend to prevent the oxidative changes which produce rancidity. The most effective antioxidants are vitamin E.
Emulsifiers
When oil is added to water, it forms a separate layer above the water. The oil and water do not dissolve in each other and are said to be immiscible. If oil and water are shaken together these two liquids become dispersed in each other and an emulsion is formed. If the liquid is allowed to stand then it reverts back to the two layers, therefore this form of emulsion is termed an unstable emulsion.
Emulsions are described as being either oil in water (O/W) or water in oil (W/O) emulsions. Margarine is termed as water in oil emulsion as small droplets of water are dispersed through the oil. In order for the oil and water to form a stable emulsion a third substance is called an emulsifying agent or emulsifier is used. In the case of margarine, the emulsifying agents most commonly used are proteins e.g. casein, lecithin or glycerol monostearate (GMS).
Stabilizers
Stabilizers are sometimes used to maintain the emulsion once it has been formed.
Colourings
Colourings are added to replace colour lost during processing. The colourings are most commonly used is Beta Carotene.
Preservatives
Preservatives are used to extend the products shelf life and to prevent microbial growth which can cause food spoilage. Products most commonly used in the manufacture of margarine.
MARGARINE PRODUCTION
Margarine is a food in the form of plastic or fluid emulsion, which is mainly type of water/oil production. Margarine is a fatty food closely resembling butter. The fat of margarine is not derived from milk fat, however at most only to a minor extent.
The term margarine is derived from Greek word ‘margarites’, meaning pearl subsequently shown to be a mixture of stearic and palmitic acids.
Margarine is now made from a water-in-oil emulsion, the aqueous phase being fat free milk and the oil phase being a blend of different oils. The two phases are mixed together and, with the aid of suitable emulsifiers, a stable emulsion is formed. The emulsion is processed until it forms a solid product having the desired consistency.
The oil blend
The selection of oils for margarine is made by the manufacturer with regard to cost, quality, and desired properties in margarine. Today; soybean, sunflower, palm, rapeseed, cotton seeds have been the most important vegetable oils used, partly in view of their availability.
The aqueous phase
About 16-18% of margarine consists of an aqueous milk preparation. In the production of aqueous phase pasteurized fresh milk or reconstituted dry milk is subjected to a ripening process. During this process diacetyl and aroma giving substances are developed.
Production
The first step in the production of margarine is the preparation of the fat blend. The fat blend may contain natural crude fats and processed fats such as fractionated, hydrogenated or interesterified mixtures. It is first refined and deodorized and then emulsified with the aqueous phase, emulsifiers being generally added at this point. Other ingredients such as vitamins, flavoring and coloring agents are usually incorporated just before emulsification.
Margarine is moulded and packed directly from the production unit. Rectangular 250 g locks are a common unit while the softer margarines are packed directly into plastic tubes.
The term margarine no longer describes a single product but a whole range of products that provide a wide variety of different blends of oils and flavors to meet every need and taste.
Additives are used in the manufacture of margarine and spreads to improve their keeping properties, appearance and stability. A number of ingredients and auxiliary materials are used in margarine, partly for taste and aroma, partly to give various physical and nutritional characteristics.
The following substances may be added to margarine:
Vitamins
Vitamin A and its esters
Vitamin D
Vitamin E and its esters
0ther vitamins
Maximum and minimum levels for vitamins A, D and E and other vitamins should be laid down by national legislation in accordance with the needs of each individual country including, where appropriate, the prohibition of the use of particular vitamins.
Sodium chloride
Sugars 2
Suitable edible proteins
FOOD ADDITIVES
Colours
Beta-carotene
Annatto extracts (calculated as total bixin or norbixin)
Curcumin or Turmeric (calculated as total Curcumin)
Beta-apo-8′-carotenal
Methyl and ethyl esters of beta-apo-8′
Carotenoic acid
Flavors
Natural flavors and their identical synthetic equivalents, except those which are known to represent a toxic hazard, and other synthetic flavors approved by the Codex Alimentarius Commission are permitted for the purpose of restoring natural flavor lost in processing or for the purpose of standardizing flavor, as long as the added flavor does not deceive or mislead the consumer by concealing damage or inferiority or by making the product appear to be of greater than actual value.
Emulsifiers
Mono- and diglycerides of fatty acids Limited by GMP
Mono- and diglycerides of fatty acids esterified with the following acids:
acetic; acetyltartaric; citric; lactic; tartaric, and their sodium and calcium salts
Lecithins and components of commercial
Polyglycerol esters of fatty acids
1, 2-propylene glycol esters of fatty acids
Esters of fatty acids with polyalcohols other than glycerol:
Sorbitan monopalmitate
Sorbitan monostearate
Sorbitan tristearate
Sucrose esters of fatty acids (including
sucroglycerides)
Preservatives
Sorbic acid and its sodium, potassium and calcium salts
Benzoic acid and its sodium and potassium salts expressed as the acids
Antioxidants
Propyl gallate 100 mg/kg
Butylated hydroxytoluene (BHT) 75 mg/kg
Butylated hydroxyanisole (BHA) 175 mg/kg
Any combination of propyl gallate, BHA,BHT
Natural and synthetic tocopherols 500 mg/kg Ascorbyl palmitate ) 500 mg/kg individually or in combination Ascorbyl stearate )
Dilauryl thiodipropionate 200 mg/kg
Antioxidant synergists
Citric acid Limited by GMP
Sodium citrate Limited by GMP
Isopropyl citrate mixture
Phosphoric acid
Monoglyceride citrate
Acidity regulators
Citric and lactic acids and their potassiumand sodium salts
L-tartaric acid and its sodium and sodium/potassium salts
Anti-foaming agent
Dimethyl polysiloxane (dimethyl silicone) singly or in combination with silicon dioxide
Contaminants
Iron (Fe) 1.5 mg/kg
Copper (Cu) 0.1 mg/kg
Lead (Pb) 0.1 mg/kg
Arsenic (As) 0.1 mg/kg
Carotene
Carotene is often labeled as good for you. However, your body converts this yellow pigment to Vitamin A, and too much Vitamin A can be harmful to your body. β-Carotene is an anti-oxidant and as such can be useful for curbing the excess of damaging free radicals in the body.
Annatto
Annatto, sometimes called Roucou, is a derivative of the achiote trees of tropical regions of the Americas, used to produce a red food coloring.
Curcumin
Curcumin is the principal curcumin of the Indian curry spice turmeric. The curcuminoids are polyphenols and are responsible for the yellow color of turmeric.
In margarines, especially those containing high levels of fat (>75%), lecithin is added as an ‘anti-spattering’ agent: it helps in suppressing spattering during shallow frying. Lecithin is admitted by the EU as a food additive, designated by Lecithin is regarded as a well-tolerated and non-toxic surfactant. E322.
Sorbic acid
Sorbic acid, or 2,4-hexadienoic acid, is a natural organic compound used as a food preservative. It has the chemical formula C6H8O2. It was first isolated from the unripe berries of the rowan (Sorbus aucuparia), hence its name.
Sorbic acid and its mineral salts, such as sodium sorbate, potassium sorbate and calcium sorbate, are antimicrobial agents often used as preservatives in food and drinks to prevent the growth of mold, yeast and fungi. In general the salts are preferred over the acid form because they are more soluble in water. The optimal pH for the antimicrobial activity is below pH 6.5 and sorbates are generally used at concentrations of 0.025% to 0.10%. Adding sorbate salts to food will however raise the pH of the food slightly so the pH may need to be adjusted to assure safety.
Sorbic acid should not be confused with other chemically unrelated, but similarly named food additives sorbitol, polysorbate, and ascorbic acid (Vitamin C).
The E numbers are:
E200 Sorbic acid
E201 Sodium sorbate
E202 Potassium sorbate
E203 Calcium sorbate
Benzoic acid
Benzoic acid and its salts are used as a food preservative, represented by the E-numbers E210, E211, E212, and E213. Benzoic acid inhibits the growth of mold, yeast[4] and some bacteria. It is either added directly or it is created from reactions with its sodium, potassium or calcium salt. The mechanism starts with the absorption of benzoic acid in to the cell. If the intracellular pH changes to 5 or lower the anaerobic fermentation of glucose through phosphofructokinase is decreased by 95%. The effectivity of benzoic acid and benzoate is thus dependent on the pH of the food.[5] Acidic food and beverage like fruit juice (citric acid), sparkling drinks (carbon dioxide), soft drinks (phosphoric acid), pickles (vinegar) or other acidified food are preserved with benzoic acid and benzoates.
Concern has been expressed that benzoic acid and its salts may react with ascorbic acid (vitamin C) in some soft drinks, forming small quantities of benzene.[6][7]
Propyl gallate
Propyl gallate, or propyl 3,4,5-trihydroxybenzoate is an ester formed by the condensation of gallic acid and propanol. It is an antioxidant added to foods containing oils and fats to prevent oxidation.
Butylated hydroxytoluene
Butylated hydroxytoluene (BHT) is a fat-soluble organic compound primarily used as an antioxidant food additive (E number E321). It is also used as an antioxidant in cosmetics, pharmaceutical drugs, jet fuels, rubber, petroleum products, and embalming fluid.
BHT is produced by the reaction of p-cresol with isobutylene. It was patented in 1947 and received approval of the Food and Drug Administration for use as a food additive and preservative in 1954. BHT reacts with free radicals, slowing the rate of autoxidation in food, preventing changes in the food’s color, odor, and taste.
Butylated hydroxyanisole
Butylated hydroxyanisole (BHA) is a mixture of two isomeric organic compounds, 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. It is prepared from 4-methoxyphenol and isobutylene. It is a waxy solid that exhibits antioxidant properties.
Like butylated hydroxytoluene (BHT), the conjugated aromatic ring of BHA is able to stabilize free radicals, sequestering them. By acting as free radical scavengers, further free radical reactions are prevented.
Evidence that BHA is a carcinogen has been obtained from animal trials.
Tocopherol
Tocopherol, or vitamin E, is a fat-soluble vitamin in eight forms that is an important antioxidant. Vitamin E is often used in skin creams and lotions because it is claimed by the manufacturers to play a role in encouraging skin healing and reducing scarring after injuries such as burns.
Natural vitamin E exists in eight different forms or isomers, four tocopherols and four tocotrienols. All isomers have a chromanol ring, with a hydroxyl group which can donate a hydrogen atom to reduce free radicals and a hydrophobic side chain which allows for penetration into biological membranes. There is an alpha, beta, gamma and delta form of both the tocopherols and tocotrienols, determined by the number of methyl groups on the chromanol ring. Each form has its own biological activity, the measure of potency or functional use in the body.
As a food additive, tocopherol is labeled with these E numbers: E307 (α-tocopherol), E308 (γ-tocopherol), and E309 (δ-tocopherol).
Ascorbyl palmitate
Ascorbyl palmitate is an ester formed from ascorbic acid and palmitic acid. Creating a fat-soluble form of vitamin C. In addition to its use as a source of vitamin C, it is also used as an antioxidant food additive (E number E304). Oral supplements of ascorbyl palmitate may be less effective, due to the substance breaking down again into its components before being digested. Ascorbyl palmitate is also marketed as “vitamin C ester.”
Ascorbyl stearate
Ascorbyl stearate (C24H42O7) is an ester formed from ascorbic acid and stearic acid. In addition to its use as a source of vitamin C, it is used as an antioxidant food additive in margarine (E number E304). The USDA limits its use to 0.02% individually or in conjunction with other antioxidants.
As a food additive, citric acid is used as a flavoring and preservative in food and beverages, especially soft drinks. It is denoted by E number E330. Citrate salts of various metals are used to deliver those minerals in a biologically available form in many dietary supplements. The buffering properties of citrates are used to control pH in household cleaners and pharmaceuticals.
Sodium citrate
Sodium citrate is the sodium salt of citric acid with the chemical formula of Na3C6H5O7. Sodium citrate possesses a saline, mildly tart, flavor. For this reason, citrates of certain Alkaline and Alkaline Earth metals (e.g. sodium and calcium citrates) are commonly known as sour salt (occasionally citric acid is erroneously termed sour salt). Sodium citrate is chiefly used as a food additive, usually for flavor or as a preservative. Sodium citrate is employed as a flavoring agent in certain varieties of club soda. Sodium citrate is common in lemon-lime soft drinks, and it is partly what causes them to have their sour taste.
Tartaric acid
Tartaric acid is a white crystalline organic acid. It occurs naturally in many plants, particularly grapes, bananas, and tamarinds, and is one of the main acids found in wine. It is added to other foods to give a sour taste, and is used as an antioxidant. Salts of tartaric acid are known as tartrates. It is a dihydroxy derivative of dicarboxylic acid.
Monoglyceride
A monoglyceride is a glyceride consisting of one fatty acid chain covalently bonded to a glycerol molecule through an ester linkage.
Mono- and Diglycerides are common food additives used to blend together certain ingredients, such as oil and water, which would not otherwise blend well.
The commercial source may be either animal (cow- or hog-derived) or vegetable, and they may be synthetically made as well. They are often found in bakery products, beverages, ice cream, chewing gum, shortening, whipped toppings, margarine, and confections.
