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Processing aids. Processing aids can be defined as substances having a desirable physical effects in connection with the manufacturing process. Processing aids include: Antifoaming agent, Releasing agents, Solvents (carrier or extraction) Enzyme and Anticaking agents,
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Processing aids • Processing aids can be defined as substances having a desirable physical effects in connection with the manufacturing process. • Processing aids include: • Antifoaming agent, • Releasing agents, • Solvents (carrier or extraction) • Enzyme and • Anticaking agents, • Firming and humectants agents 1
Anti-foaming agents • Anti-foaming agents aid in preventing excessive foaming of liquids during boiling, pumping or when being filled into bottles. • The international list includes two substances as antifoaming agent, they are Oxystearin and polydimethlsiloxane. • Fortunately the two substances have been evaluated.
Oxystearin : it is a mixture of glycerides having partially oxidized stearic and other fatty acids. • It is used as antifoaming agents, seqnesterant and crystallization inhibitor. • Oxystearin is used in cooking oils, salad oils and beet sugar and yeast. • With regard to regulation , oxystearin is permitted for use with limitation of 0.125% of the wt. of the oil. • The ADI for oxystearin is 0-25 mg/kg wt. 3
Releasing agents • Releasing agents are substances • that enable food products deposited in moulds to be effectively de-moulded without sticking • or to prevent boiled sugar from sticking • or to prevent boiled sugar from sticking to the cooking pan in candy processing. • The international list includes only one releasing agents, it is the castor oil. • Castor oil is used as a releasing agent in hard candy and vitamin and mineral of 500 ppm . 4
Permitted antifoaming, releasing and encapsulating agents according to JECFA lists 5
Solvents • Solvents may be classified to extraction solvents and carrier solvents. • Extraction solvents: they are used to extract a desirable ingredients like caffeine from coffee. • Carrier solvent: they aid in dispersing more homogeneously a small amount of ingredient in a very much larger amount of mixture like flavoring, vitamin …etc. • The international list includes more than 30 substances used as extraction solvent. 6
Also only two of these solvents have been evaluated; hexane and CO2 . • This however does not mean that these solvent still not evaluated. • If we look to a recent or new reference we will find most of them have been evaluated; specially by other countries or agencies such as FDA. • Benzyl alcohol : This additive as example is not evaluated in the international list but is evaluated by the FDA. • While it used as carrier solvent in the international list it is permitted for use as flavoring agent in the USA. 7
Acetone : this is another example for an additive which is not evaluated by the international agencies while it is evaluated by the FDA. • It is used is extraction solvent and color diluent. • It is permitted for use in fruit spice oleoresins and vegetable • With regard to regulations, there should be no residue, and limitations of 30 ppm in spice oleoresins. • In addition, there is a new term or expression appeared recently; it states; on community right to know list, and acetone is covered by this regulation. 8
Enzymes • Enzymes are easily defined as organic catalysts, • they can be used in very small quantities to bring about change and are not themselves attired in the course of the reaction. • Enzyme are found in all living organism , plants, animal, insects, fungi, and bacteria. • Since enzyme are built of complex proteins they function best at temperature which approximate to body temperature in about 25-35°C. 12
The reactions that enzymes have been used as mixture in fermentation for centuries • It is only in the last 25 years that the isolation of individual enzymes has been carried out. • However, until now the industrial use of single or relatively pure enzymes by food industry is still in its infancy. 13
Using of enzymes in the food industry stem from the knowledge of the digestive system. • In meat tenderization the two enzymes papain and bromelain are used. • Protein hydrolysates are also prepared from meat and meat-by products using the proteases such as the pepsin and trypsin enzymes. • Rennin is used in cheese making it is either from microbial sources or from bovine stomach. 14
Glucose oxidase isolated from Aspergillus niger is used to prevent browning reactions and to stabilize vitamin B12 and C preparations and to prevent rancidity….etc. • Catalase produced from the mold Aspergillus niger and used in dairy industry. • Carbohydrases and amylase are used in processing of starch or corn syrups, invert sugar, modified starches, baking and candy industry.
Recently, immobilized enzymes have been used in the food industry to overcome the problems of conventional enzymes such as level low activity, low thermal stability and difficulty of re-using the enzyme. • As a result, enzymes were attached or anchored to a surface which may be inert such as glass beads or to some molecular as pectin, directly to the bacterial or fungal cells, and this technique is called immobilization and the product is called immobilized enzymes. 16
Fruit juices, cheese making and corn syrup industries are the main applications for immobilized enzymes. • If we look at the international list we will find about 36 enzyme preparations allowed for use in foods. • Two enzymes were only evaluated until 1984. Fortunately more than 10 other enzymes were evaluated and included in American list. • As you can see from the transparency the 1st 6 enzyme are immobilized enzymes. 17
Example for 2 enzymes will follow. • Carbohydrase, Asperigillus it is obtained by the fermentation of Aspergillus oryzae ; • It is used as production aid and tenderizing agent; it is permitted to be used in many foods like alcoholic beverages, baking products, dairy products , meat poultry and starch syrups. • Regulations state that its injection as a soln to meat should not result in more than 3% increase in wt. of product . 18
Ficin : it is a proteolytic enzymes taken from the fig. tree latex and used as enzymes meat tenderizing preparation of precooked cereals , tissue softening agent it is permitted for use in cereals , meats ,poultry , beer , wine. • With regard to regulations ,it is considered GRAS when used in accordance with GMP. • What apply also for carbohydrase apply also for ficin with regard to the gain in wt. of the injected tissue. (not more than 3%) 19
Anti-caking agents • Anti-caking agents are chemicals added to powdered or granular food to prevent them from absorbing moisture and becoming lumpy or not free flowing. • Anti-caking agents are either anhydrous salts that can pick up moisture without themselves becoming wet but can be readily hydrated by binding the water • or are substances that hold water by surface adhesion yet themselves remain free flowing . 22
It is of interest to note some discrepancies regarding the anti-caking agents in the International, British and American lists. • The International list includes more than 28 substances, where most of them have been evaluated. These substance can he grouped as the following : • A. The Ca, Mg, Al, Na and K salts of silicic acids or silicate or a mixture of them. • B. Ca, Mg, Na and K Ferro cyanide. Some people tried to commit suicide by taking the Na Ferrocyanide believing that the cyanide it contains will kill them.
In fact the Ferrocyanide are not toxic since the cyanide is not free but is tightly bound to iron, however, the Ferrocyanide are not included in the British list • C. Cellulose • D. Al, Ca, Na, Mg, k, and NH4 salts of long chain fatty acids like stearic , palmitic, lauric, myristic and oleic acids. • E. Mg , and Ca carbonate and Mg bicarbonate and • F. Ca , Mg and Na phosphates
G. Sodium Ferrocyanide: it is used as anticaking agent or processing aid in sodium chloride. It is considered GRAS with some limitation. • H. Magnesium silicate hydrate : it is permitted for use as anticaking agent in table salt and it is considered GRAS with a limitation of 2% • I. Calcium stearate: it is used as anticaking agent, emulsifier, stabilizer, thickener and flavoring agent. It is permitted to be used in many foods such as sugar, candy, dry molasses, vanilla and yeast. It is considered GRAS when used in accordance with GMP.
J. Cellulose, powdered: it is used as anticaking agent, filter aid, thickening agent …. Etc. • It is permitted to be used in various foods. • It is considered GRAS when used in accordance with GMP • K. Calcium phosphate, tribasic: it is used as anticaking agent, buffer, stabilizer and dietary supplement. • It is permitted to be used in many foods like cereal flour, desserts, table salt, dry vinegar, and packaging material ….etc. • It is also considered GRAS when used in accordance with GMP.
Firming and crisping agent • Firming and crisping agents can be defined as substances used to or have the ability to preserve the texture of vegetable tissues by keeping them turgid, thoroughly maintaining the water pressure inside them. • They aid this by preventing loss of water from the tissues. • About 13 food additives are allowed to be used as firming agent. They are included in the international list; 8 of them have been evaluated. These agents are mainly Al, Ca, and Mg salts. • Aluminum potassium sulphate: it is used as firming agent, buffer and neutralizing agent, permitted for use in various foods, and considered GRAS when used in accordance with GMP.
Humectants • Humectants : opposite to anticaking agents whose main aim is to keep certain food products dry; humectant aim to keep certain food moist, such as bread and cake. • It is will know also that humectants aid in food preservation throw lowering the aw of the food they contain and they do this due to their low molecular weight. • Glycerol and sorbitol are two famous humectants and the international lists include another 81 humectants. As we see many of these agents like sorbitol, glycerol are multifunction or multipurpose food additive • Glycerol or glycerine: they are needed as humectant , solvent and bodying agents, permitted for use in candy, baked goods, and packaging material. It is considered GARS when used in accordance with GMP. 28
Permitted anti-browning, firming and crisping and humectants agents according to JECFA lists 29
Permitted processing aids in JECFA lists after 2004 modification 30
Permitted processing aids in JECFA lists after 2004 modification 31
Sweeteners • The general term “sweeteners” is used for a number of different substances. • These substance may differ in their • chemical structure, • degree of sweetness , • source , • application and so on. • As a result different method for classification of sweeteners are available in the literature.
The best classification found is that which classifies sweeteners to three groups : • the 1st is the sugar and its related compounds: • sucrose , • fructose , • glucose , • hydrolyzed starch syrups, • isomerized glucose syrups and • high fructose corn syrups. • All these products are derived from agricultural sources.
The 2nd group is the bulking sweetness. • These sweeteners • supply bulk, • have limited sweetness • not easily metabolized by bacteria and • are relatively acceptable to some extent to diabetics. • This group includes, sorbitol, manitol, xylitol, isomalt, maltitol, lactitol, mixtures of sorbitol and maltitol, hydrogenated starch syrup.
The 3rd group is the intense sweeteners; • these sweeteners are from 30 to 40 to several thousand sweets than sucrose; • they can’t supply technical function, • can’t contribute to the energy content of the food and • are acceptable for diabetics. • Saccharin, cyclamate, aspartame, Acesulfame K, dulcin and thaumatin are the most popular members in this class of sweeteners.
Sugar and related compound • Sugar and related compound have almost similar sweetness intensities. • Source is generally used as standard and is given the sweeteners intensity 1. • Glucose is less sweet than sucrose and fructose is slightly sweeter. • These sugars are metabolized in human body and contribute energy; • they impart technical benefits to the product they are used in such as • supply of bulk in candy, bakery product, jams and marmalade and chewing gums; • they give humectant properties resulting in preservative effect due to reducing aw in jams and marmalades;
they impart also gelling assistance in jams and marmalades. • Advantages of sucrose and related product to the food industry are: • the large supply ; • low prices; • lack of regulatory problems and • favorable taste characteristic. • Their disadvantage are : • increasing concern of consumers about health effects like • fattening, • supply of so called “empty calories” and • cariogenic properties. • Nevertheless, sucrose is still the most important sweetening agent in quantity terms.
Bulking Sweeteners • Bulking sweeteners are mainly the sugar alcohol and polydextrose. • Sugar alcohols have many benefits like sugar and related products group • i.e. similar to them in sweetness intensity; • they impart technical functions as sugar do (bulking functions, humectant properties). • The main advantage of sugar alcohols is their more suitability for diabetics compared with sugars due to their slow absorption in the human body;
also the sugar alcohols are less cariogenic than sugars. • While the sorbitol, mannitol and xylitol are fully metabolized and contribute energy intake; • the disaccharide alcohol are slowly absorbed from the intestine and at least partially exerted without utilization by the body. • Therefore, production of sweets, chewing gums, chocolate and bakery products of low calorie content is possible by using the disaccharide alcohol.
However, the general limitation of all sugar alcohols is their laxative effect when consumed in high doses. • Several countries require a warning statement at the labels of products containing substantial amounts of sugar alcohols • Polydextrose, a glucose polymer is of rather low laxative effect and tolerated by diabetics and due to its low sweetness, it is of lower calorific value ,so, it is expected to find more application compared with sugar alcohols.
Intense sweeteners: • Intense sweetenersare not metabolized by the bacteria in the oral cavity , • so they are not cariogenic, • also they areacceptable for diabetic and • they do not contribute energy. • Another benefits of intense sweeteners is their high sweetness intensity. • It is for 30 for cyclamates; 180 for aspartame; 300 for saccharin and several thousands for thaumatin.
The main disadvantage for these intestine sweeteners is • the consumer concern about their safety. The banning of cyclamate and saccharin in some countries is examples. • Cyclamate and saccharin have been proved to be experimentally carcinogens; • however, saccharin is still in use in USA while the international list still include the cyclamate and saccharin. • Cyclamates are recovering from attacks started in 1969 and the resulting bad reputation. • There is a general tendency to restrict their maximum level in foods and beverages.