Deodorization

Deodorization is essentially vacuum steam distillation (190-230 °C, 0.5-10 mbar). The volatile compounds, together with undesirable odorants present in the fat or oil, are separated in this re- 

In steaming or physical refining, the double bonds of linoleic and Unolenic acid isomerize to a small extent. For this reason, an HPLC determination of isomeric linoleic acids is used to distinguish between refined and natural plant oils (cf. 14.5.3.4). 

A patent describes a continuous process for deodorizing oils with carbon dioxide at 150-250°C and 100-250 Bars (Zosel, 1979). Impurities extracted with carbon dioxide are removed by a solid adsorbent, such as activated charcoal, before the carbon dioxide is recycled to the deodorizer column. The FFA content of soybean oil comd be lowered from 0.4 to 0.02% by using this technology. 

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Dentistry Dentrifices Denture adhesives Denture cleaners Dentures Deodorant... 

The aerosol container has enjoyed commercial success ia a wide variety of product categories. Insecticide aerosols were iatroduced ia the late 1940s. Additional commodities, including shave foams, hair sprays, antiperspirants, deodorants, paints, spray starch, colognes, perfumes, whipped cream, and automotive products, followed ia the 1950s. Mediciaal metered-dose aerosol products have also been developed for use ia the treatment of asthma, migraine headaches, and angiaa. 

Personal products are the fastest growing segment of the aerosol industry and represent the largest of the categories. An iacrease in the use of hair spray as well as deodorants and antiperspirants accounts for the major growth. Increase in industrial aerosol automotive products was also large in the 1980s. 

Sprays. Aerosol spray emulsions are of the water-in-oil type. The preferred propellant is a hydrocarbon or mixed hydrocarbon—hydrofluorocarbon. About 25 to 30% propellent, miscible with the oil, remains in the external phase of the emulsion. When this system is dispensed, the propellant vaporizes, leaving behind droplets of the w/o emulsion (Fig. 2b). A vapor tap valve, which tends to produce finely dispersed particles, is employed. Because the propellant and the product concentrate tend to separate on standing, products formulated using this system, such as pesticides and room deodorants, must be shaken before use. 

Hydrocarbons have, for the most part, replaced CFCs as propellants. Most personal products such as hair sprays, deodorants, and antiperspirants, as well as household aerosols, are formulated using hydrocarbons or some form of hydro-carbon—halocarbon blend. Blends provide customized vapor pressures and, if halocarbons are utilized, a decrease in flammabiUty. Some blends form azeotropes which have a constant vapor pressure and do not fractionate as the contents of the container are used. 

Another dynamic iastmment, the Scentometer, is the basis for odor regulations ia the states of Colorado, Illinois, Kentucky, Missouri, Nevada, and Wyoming, and ia the District of Columbia (324). The portable Scentometer (Bameby-Cheney) can produce dilution ratios up to 128 1 ia the field. The Scentometer blends two air streams, one of which has been deodorized with activated carbon. The dilution ratio is decreased until the odor becomes detectable (325). Improvements to dynamic methods have been recommended (326). 

Wkiterization is a specialized appHcation of fractional crystallization that is utilized to remove saturates or waxes from Hquid oils. Salad oils, which do not cloud at refrigerator temperature, have been produced by winterizing lightly hydrogenated soybean ok. However, many producers now use refined, bleached, deodorized oks for this purpose (24). 

DeodoriZation. Removal of volatile odorous material and residual fatty acids is the final step ki ok processkig prior to packagkig or filling for bulk shipment (28). The ok is heated to 230—260°C under vacuum. Steam is passed through the ok to assist ki carrying over the volatile material. 

Aldehydes, enals, dienals, ketones, and hydrocarbons, which are responsible for disagreeable odors, generally bok at lower temperatures than fatty acids. Analysis showkig a free fatty acid concentration of less than 0.05% is an kidication that deodorization is sufficientiy complete. Some of the dienals have very low odor thresholds and sensory evaluation of the finished ok is a judicious quaHty assurance step. 

Deodorization can be carried out ki batch, continuous, or semicontkiuous systems. Figure 4 shows a typical design for a semicontkiuous deodorizer. The heated ok is passed through a series of trays under vacuum. Steam is passed through the ok through a steam sparge ki the bottom of the tray. Volatiles are carried through the headspace and condensed. In addition to fatty acids and compounds responsible for odor, some tocopherols and sterols are also distilled kito the condensate. The amount of tocopherols distilled depends on deodorization temperature and vacuum. 

Table 4. Viscosity of Deodorized Oils and Fats at Different Temperatures ...

The most common use of 2-(2, 4 -dichlorophenoxy)-5-chlorophenol (2,4,4 -trichloro 2 -phenoxyphenol) is in the personal care products market, where it is commonly known as triclosan and is the active antibacterial in underarm deodorants. It has also found some acceptance as an antibacterial component of plastic mattress covers. 

The successful employment of any insecticide depends on its proper formulation into a preparation that can be appHed for insect control with safety to the apphcator, animals, and plants. Insecticides are commonly formulated as dusts, water dispersions, emulsions, and solutions. The preparation and use of such formulations involves accessory agents such as dust carriers, solvents, emulsifiers, wetting and dispersing agents, stickers, and deodorants or masking agents (1). 

Magnesium acetate also has uses as a dye fixative in textile printing, as a deodorant, disinfectant, an antiseptic in medicine, and as a reagent chemical (see Disinfectants AND ANTISEPTICS Textiles) (6). In the United States, Hoescht-Celanese and Tennessee Eastman are the principal producers of magnesium acetate. These companies make about 36,000 t/yr, which is largely used in-house for the production of cellulose acetate. 

Microcapsules are used in several film coatings other than carbonless paper. Encapsulated Hquid crystal formulations coated on polyester film are used to produce a variety of display products including thermometers. Polyester film coated with capsules loaded with leuco dyes analogous to those used in carbonless copy paper is used as a means of measuring line and force pressures (79). Encapsulated deodorants that release their core contents as a function of moisture developed because of sweating represent another commercial appHcation. Microcapsules are incorporated in several cosmetic creams, powders, and cleansing products (80). 

Industry has standardized procedures for the quantitative sensory assessment of the perceived olfactory intensity of indoor malodors and their relationship to the deodorant efficacy of air freshener products. Synthetic malodors are used for these evaluation purposes. These malodors should be hedonicaHy associated to the "real" malodor, and must be readily available and of consistent odor quaUty. These malodors should be tested in various concentrations and be representative of intensities experienced under normal domestic conditions. 

Masking. Masking can be defined as the reduction of olfactory perception of a defined odor stimulus by means of presentation of another odorous substance without the physical removal or chemical alteration of the defined stimulus from the environment. Masking is therefore hyperadditive it raises the total odor level, possibly creating an overpowering sensation, and maybe defined as a reodorant, rather than a deodorant. Its end result can be explained by the simple equation of 1 + 1 = >2 (Fig. 2a). 

Pine Oil. This oil is obtained by extraction and fractionation or by steam distillation of the wood of Pinuspalustris Mill, and other species. Most of the oil is produced ia the southeastern United States. The composition of the oil depends on the fractions chosen, but the chief constituents are terpene alcohols, mainly terpiaeol. Piae oil finds use as a germicide ia disiafectants and soaps as an ingredient ia iasecticides, deodorants, poHshes, sweepiag compounds, and catde sprays and as raw material for the manufacture of perfumery-grade terpiaeol [8000-41 -7], anethole [104-46-1], fenchone (137), and camphor (35). 

Isopropyl alcohol is also employed widely as a solvent for cosmetics (qv), eg, lotions, perfumes, shampoos, skin cleansers, nail poHshes, makeup removers, deodorants, body oils, and skin lotions. In cosmetic appHcations, the acetone-like odor of isopropyl alcohol is masked by the addition of fragrance (144). 

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