Other ingredients

1 Acidulants. The preferred acidulant for dilutable (and other) soft drinks is citric acid, which is readily available both as a crystalline solid (citric acid anhydrous) and as a 50% w/w solution in bulk. Other acidulants that are used in specific products include malic acid, lactic acid and tartaric acid. Phosphoric acid, until recently permitted only in cola drinks, is now available for use in the United Kingdom but has so far found little, if any, use in dilutable products. Acids other than citric are usually employed only where a slightly different taste profile is needed. Ascorbic acid is usually employed as an antioxidant rather than as a direct acidulant. 

Sulphur dioxide remains a key preservative in dilutables containing fruit components, where it is permitted (at least in the United Kingdom) at a rate of 250 mg/1. This preservative, which is a gas in solution in the product, will diffuse into the product headspace and help to minimize microbial development. 

It is normal to use additionally a mixture of both benzoic and sorbic acids, added as their sodium and potassium salts respectively. Current UK preservative regulations permit a maximum level of 300 mg/1 of sorbic acid and 150 mg/1 of benzoic acid, both at drinking strength. For this reason it is normal to suggest on the product label a dilution ratio, which can then be used as a factor in calculating the amount of these preservatives to be used. An example is set out in Table 6.7. 

In most dilutables, these levels would be more than adequate to deliver enough preservation after pasteurisation, and a typical preservative mix for a dilutable containing up to 25% fruit juice might be as follows  

Preservative Max. ready-to-drink level mg/1 Dilution recommended for product Max. level in dilutable 

Discussions of starch and its performance in foods too often overlook the other ingredients present and the role that interactions play in the starch s functionality. The following sections describe the effects of common food ingredients on starch function. 

greater than pH 11, will effect gelatinization under mild heating.206 

Potato starch contains 0.07 to 0.09% phosphate mono-ester groups.53 This native monosubstitution makes the starch anionic and sensitive to the presence of other ions. Similarly, the US Code of Federal Regulations allows up to 0.4% phosphate 

The use of chain transfer agents in emulsion polymerization was briefly discussed in Sect. 2.2.1. As stated, the most commonly used chain transfer agents are the mer-captans (thioalcohols) RSH, although a wide range of other compounds also exert a modifying effect during polymerization, for example carbon tetrachloride, certain disulfides, rosin acid salts, 4-vinylcyclohexene (butadiene dimer) amongst many others, which may also include impurities in other raw materials. 

The effectiveness of a chain transfer agent is denoted by its transfer constant, e, which is the ratio of rate of the chain transfer step to the propagation step  

To introduce heat sensitivity into the polymer (cross-linking which occurs after polymerization, usually when a dried polymer film is heated), two commonly used monomers are N-methylolacrylamide and N-methylolmethacrylamide. The structure of N-methylolacrylamide is as foUows  

Incorporation into the polymer backbone takes place through the vinyl double bond. Cross-linking then takes place between two methylol groups. 

Electrolytes. Electrolytes are added for several reasons. For example, they can control the pH (buffers), which prevents hydrolysis of the surfactant and maintains the efficiency of the initiator. The addition of electrolytes can lead to more monodisperse particles but also to coagulation. 

Chain transfer agents. Emulsion polymerisation may result in an unpractically high molecular mass polymer. To reduce the molar mass, CTAs, usually mercaptans, are frequently used. The mercaptan is introduced into the reactor together with the monomer phase. The consmnption of the mercaptan taking place in the loci should be properly kept in balance with monomer consumption. 

Sequestering agents. In redox systems, adventitious metal ions can catalyse radical formation in an uncontrolled way. So-called sequestering agents (e.g. EDTA) are added to prevent this. Also these sequestering agents keep the metal ions in solution (e.g. Fe at higher pH). 

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In manufacture, the abrasive grain is mixed with cmde mbber, sulfur, and other ingredients for curing, then passed through calender roUs to produce a sheet of desired thickness. The wheels are stamped from this sheet and heated under pressure to vulcanise the mbber. 

After the mbber latex is produced, it is subjected to further polymerization in the presence of styrene (CgHg) and acrylonitrile (C H N) monomers to produce the ABS latex. This can be done in batch, semibatch, or continuous reactors. The other ingredients required for this polymerization are similar to those required for the mbber latex reaction. 

The main features in which the Radford process differs from the batch operation are in thermal dehydration and compounding. Water-wet nitrocellulose on a continuous vacuum belt filter is vacuum-dried followed by hot air transfusion (80°C) to reduce the moisture to less than 2%. After cooling, alcohol is sprayed on the nitrocellulose to a concentration of 15—20%. The alcohol-wet nitrocellulose is then transferred from a surge feeder to a compounder by a continuous weigh-belt along with the other ingredients of the composition, which are also weighed and added automatically. 

Effects on Visible Smoke. Smoke is a main impediment to egress from a burning building. Although some examples are known where specific phosphoms flame retardants increased smoke in small-scale tests, other instances are reported where the presence of the retardant reduced smoke. The effect appears to be a complex function of burning conditions and of other ingredients in the formulation (153,156,157). In a carehil Japanese study, ammonium phosphate raised or lowered the smoke from wood depending on pyrolysis temperature (158). Where the phosphoms flame retardant functions by char enhancement, lower smoke levels are likely to be observed. 

In the compounding technique, constituents are selected or rejected because of their odor, taste, and physical chemical properties, eg, boiling point, solubihty, and chemical reactivity, as weU as the results of flavor tests in water, symp, milk, or an appropriate medium. A compound considered to be characteristic is then combined with other ingredients into a flavor and tested as a finished flavor in the final product by an appHcations laboratory. 

Fillers (qv) are occasionally used in flexible slab foams the two most commonly used are calcium carbonate (whiting) and barium sulfate (barytes). Their use level may range up to 150 parts per 100 parts of polyol. Various other ingredients may also be used to modify a flexible foam formulation. Cross-linkers, chain extenders, ignition modifiers, auxiHary blowing agents, etc, are all used to some extent depending on the final product characteristics desired. 

Emulsifiers are classified by the hydrophilic—lipophilic balance (HLB) system. This system indicates whether an emulsifier is more soluble in water or oil, and for which type of emulsion (water-in-oil or oil-in-water) it is best suited. Emulsifiers having alow HLB value are more oil soluble, and are better suited for water-in-oil appHcations such as margarine. Conversely, emulsifiers having a high HLB value are more water soluble, and function more effectively in oil-in-water emulsions such as ice cream (34). The use of this system is somewhat limited because the properties of emulsifiers are modified by the presence of other ingredients and different combinations of emulsifiers are needed to achieve a desired effect. The HLB values of some common emulsifiers are given (35). 

In the United States, 62% of fluid milk production is used for manufactured products, mainly cheese, evaporated and sweetened condensed milk, nonfat dry milk, and ice cream. Evaporated and condensed milk and dry milk are made from milk only other ingredients are added to make ice cream and sweetened condensed milk. 

Typical cosolvents include methanol [67-56-17, ethanol [64-17-5] isopropyl alcohol [67-65-OJ, or toluene. The selection of cosolvents depends on the requirement of the formula and their interaction with other ingredients. Methanol is a common cosolvent in methylene chloride formulas since it has good solvency and is needed to swell ceUulose-type thickening agents. A typical methylene chloride formula used to strip wood is as follows (7). 

Finish removers are manufactured in open or closed ketdes. Closed ketdes are preferred because they prevent solvent loss and exposure to personnel. To reduce air emissions from the solvents, condensers are employed on vent stacks. Mild steel or black iron ketdes are used for neutral or basic removers stainless steel (316 or 317) or reinforced polyethylene ketdes are used for acidic removers. The ketdes are heated to increase dispersion of paraffin waxes and aid in the mixing of other ingredients. Electric or air driven motors drive either sweeping blade or propeller mixers that give sufficient lift to rotate and mix the Hquid. Dispenser-type mixers are used to manufacture thick and viscous removers. Ketde, fittings, mixer, and fill equipment must be fabricated with materials resistant to the chemicals in remover formulas. 

Formulated metal poHshes consist of fine abrasives similar to those involved in industrial buffing operations, ie, pumice, tripoH, kaolin, rouge and crocus iron oxides, and lime. Other ingredients include surfactants (qv), eg, sodium oleate [143-19-1] or sodium dodecylben2enesulfonate [25155-30-0], chelating agents (qv), eg, citric acid [77-92-9], and solvents, eg, alcohols or aUphatic hydrocarbons. 

When considering sealants or other formulated products, the health and safety considerations relating to the other ingredients should be taken into account. 

In the Reclaimator, a high pressure extmder, fiber-free mbber is heated to 175—205°C with oils and other ingredients. High pressure and shear between the mbber mixture and the extmder barrel walls effectively devulcanize the mixture in one to three minutes. In the Lancaster-Banbury method, high temperature, pressure, and shear are appHed to the mbber in a batch process that is otherwise similar to the Reclaimator process. In another high pressure process, scrap mbber is devulcanized at 5.5—6.9 MPa (54—68 atm) for ca five minutes. The product is milled, baled, or pelletized as in other processes. 

PVC. Poly(vinyl chloride) (PVC), a very versatile polymer, is manufactured by the polymerisation of vinyl chloride monomer, a gaseous substance obtained from the reaction of ethylene with oxygen and hydrochloric acid. In its most basic form, the resin is a relatively hard material that requites the addition of other compounds, commonly plasticisers and stabilisers as well as certain other ingredients, to produce the desired physical properties for roofing use. The membranes come in both reinforced and nonreinforced constmctions, but since the 1980s the direction has been toward offering only reinforced membranes. The membrane thickness typically mns from 0.8—1.5 mm and widths typically in the range of 1.5—4.6 m. 

Other ingredients besides the elastomer and the cure system itself influence cure and scorch behavior. Usually the effect of a material on cure is pH-dependent. Ingredients which are basic in nature tend to accelerate the rate of both scorch and cure, whereas acidic materials exhibit the opposite effect. 

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