Additives in commercial food preparation

Food additives are chemical substances, other than basic foods, used in commercial food preparation to achieve preservative, flavor, color, stability, and aesthetic effects. Though some of the chemicals used are derived naturally, most of the additives used in food production are synthetic and with little or no nutritional value.i22 23] A glance at almost any cookbook shows that chemical additives are not necessary for food preparation. Their use allows inferior ingredients to be used, extends the shelf lives of many products, and exposes people to toxic chemicals. 

Emulsification. Emulsifiers, such as lecithin, are used to keep oil and aqueous phases in salad dressings from separating. 

Thickening. Thickeners, such as carrageenan and carboxymethyl cellulose, are used to thicken ice cream and jelly and impart texture to bread and cake. 

Enrichment. Vitamins and minerals, such as vitamin D, thiamin, and niacin, are added to fortify milk and flour. 

Anticaking. Anticaking agents, such as sodium aluminosilicate in salt and silicon dioxide in powdered milk and nondairy creamers, for example, are used to prevent coagulation. 

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Food additives number in the thousands. Addressing all of these is beyond the scope of this book. The following sections are illustrative of the toxicants used in commercial food preparation. 

Pectinex Ultra SP-L is a commercial enzyme preparation from Aspergillus acu-leatus that is used in the food industry for reducing viscosity in fruit juice processing. It contains different pectinolytic and cellulolytic enzymes [29]. In addition, the existence of fructosyltransferase activity in Pectinex Ultra SP-L has been reported by several authors [30-32]. In recent years, we have investigated the purification, characterization, and application of the fructosyltransferase from A. aadeatus contained in this commercial preparation [33]. 

Experts invited by FAO also prepare Chemical and Technical Assessments (CTA) for the substances on the agenda to provide the committee with the information on the physical and chemical characteristics of the additive, on the raw material(s) used in commercial production of the additive, and on methods of manufacture by which the raw materi-al(s) is converted into a finished commercial food additive. It is acknowledged that some of these data may be trade secrets. Therefore, such data are held in strict confidence. Furthermore, the CTA includes information on impurities including intermediates, functional use(s) with the technological purpose for using the additive and the levels of use on a commodity basis, reactions and fate in food, and effects on nutrients. In the case of contaminants, FAO experts are responsible for gathering information on their occurrence in food and methods for their analysis. 

Clearly, all the additives listed in the section above are not present in any one food. An examination of the composition of ordinary white bread, however, reveals just how many of these are found in the food we eat every day. Table 10.4 lists the ingredients of a commercially prepared white... 

Fulder adds the well-known faet that garUe is not only an antibiotie, but serves to cleanse the body of toxic heavy metals. Cysteine, for example, is specific to removing lead, and evrai mercury, and in Bulgaria there is a commercial garlic preparation called Satal for these purposes. Additionally, garlie provides a way to cleanse the body of food additives and solvraits. 

Much of the safety support comes from the fact that CIA is already consumed in the human diet, especially in ruminant derived products, without apparent adverse effects. However, the isomeric composition of naturally occurring CLA is different from the CIA available as food supplements. Ruminant meat and dairy products contain mainly the cis-9,trans- 1 CLA isomer, whereas commercial CLA preparations generally contain equal proportions of the cts-9,trans- and the trans-l0,cis-l2 CLA isomer. There is a growing body of evidence that these two isomers have very distinct biological functions (1). In addition, the intake of CLA from natural dietary sources was calculated to range from 150—400 mg/day (2, 3), whereas the recommended intake for commercial CLA supplements varies from 1 to 3.4 g/day. The safety assessment of CLA based on the natural occurrence in the diet is therefore limited. 

Semi-permeable membranes, such as those used in ultrafiltration, have many potential applications in the food industry. Ishikawa and Nara (1992) pointed out, however that the main problem with these systems was the permeation of the solute used in osmosis into the foodstuff. This could be controlled by the use of a semi-permeable membrane placed in intimate contact with the food, that is, with no free space between the membrane and the food. They investigated the use of a membrane made from a chitosan gel. Chitosan is prepared from chitin, a glycan separated commercially from the shells of crustaceans. Chitosan is both semi-permeable and edible. They postulated that food could, therefore, be coated with a chitosan membrane, thereby eliminating any free space. As yet, chitosan is not permitted as an additive in foods, but this technique may find wide applications in the food industry if chitosan were to be accepted as a processing aid for foodstuffs. 

In addition to the pigment concentration in the respective food source, the color quality is of major importance for plant material quality assessment and selection during production and storage. Color quality also strongly affects consumer purchase decisions. Since red beet is still the sole betalain source exploited commercially, quality parameters have been developed for beet preparations. The most important one is the so-called color shade representing a ratio of two absorbance values, namely for betaxanthins and for betacyanins, respectively, A (at 535 mn)/A (at 480 nm). 

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