Foods, chemicals

Analytical Procedures. Standard methods for analysis of food-grade adipic acid are described ia the Food Chemicals Codex (see Refs, ia Table 8). Classical methods are used for assay (titration), trace metals (As, heavy metals as Pb), and total ash. Water is determined by Kad-Fisher titration of a methanol solution of the acid. Determination of color ia methanol solution (APHA, Hazen equivalent, max. 10), as well as iron and other metals, are also described elsewhere (175). Other analyses frequendy are required for resia-grade acid. For example, hydrolyzable nitrogen (NH, amides, nitriles, etc) is determined by distillation of ammonia from an alkaline solution. Reducible nitrogen (nitrates and nitroorganics) may then be determined by adding DeVarda s alloy and continuing the distillation. Hydrocarbon oil contaminants may be determined by ir analysis of halocarbon extracts of alkaline solutions of the acid. 

Food Chemicals Codex, 3rd ed.. National Academy of Sciences, National Academy Press, Washiagton, D.C., 1981. 

Fine chemicals are produced by a wide spectmm of manufacturers, largely because the distinction between different kinds of chemicals is not sharp. There are specialty producers of fine chemicals. Many companies that manufacture dmgs also manufacture the chemical substances that are used in preparing the dosage forms. A number of companies manufacture dmg chemicals and food chemicals. Some fine chemicals are made by manufacturers of heavy chemicals, and either may be simply a segment of their regular production, or some of that production which has been subjected to additional purification steps. Many fine chemicals are imported into the United States from countries such as Japan, Germany, and the Netherlands. 

Standards for food-grade chemicals in the United States are set by the Committee on Eood Chemicals Codex of the National Academy of Sciences (NAS) which pubHshes them in the Food Chemicals Codex (ECC) (6) (see also Eood additives). Standards for laboratory reagents are set by the American Chemical Society (ACS) Committee on Analytical Reagents and are pubHshed in Feagent Chemicals—A.CS Specifications (7). Standards for electronic-grade chemicals, which have extremely low limits for trace ions, are pubHshed aimually in The Book of SEMI Standards (BOSS) by Semiconductor Equipment and Materials International (SEMI) (8). 

Action to compile standards for food-grade chemicals did not take place until after the enactment of the Food Additives Amendment to the Food, Dmg, and Cosmetic Act in 1958 (13). This amendment stated that substances added to foods should be of food-grade quaUty, but it contained no criteria by which such quahty could be determined (see also Colorants forfood, drugs, cosmetics, and medicaldevices). The Food Protection Committee of the National Academy of Sciences—National Research Council (NAS—NRC) therefore undertook the project of producing a Food Chemicals Codex. 

The objective of the FCC is to define food-grade chemicals in terms of the characteristics that estabUsh identity, strength, and quahty. It provides specifications in monograph form for some 900 food additives, together with analytical test procedures by which compliance with the specifications can be determined. The third edition was pubUshed in 1981 supplements followed in 1983, 1986, 1991, and 1993. The fourth edition is in preparation as of this writing and is to include monographs for almost 1000 food chemicals, including flavors. 

The Food Chemicals Codex. The Food Chemicals Codex is developed by the Committee on Pood Chemicals Codex, which is a part of the Pood and Nutrition Board, Institute of Medicine, National Academy of Sciences, under a contract with the U.S. PDA. The Committee has the responsibihty for the development and revision of the PCC. To meet this responsibiUty, the Committee also contacts manufacturers, trade associations, and other knowledgeable parties to obtain comments and criticisms of monographs proposed by the committee. Broader pubHc input is sought by pubhcation, by the PDA in the FederalFegister, of current committee activity regarding new and revised monographs proposed for inclusion in the PCC. 

The Food Chemicals Codex defines food-grade quaUty for the identity and purity of chemicals used in food products. In the United States, the FDA adopts many of the Food Chemicals Codex specifications as the legal basis for food-grade quaUty of flavor and food chemicals. 

Properties. Limited data are available for the types or grades of commercial agar which is usually in the form of chopped shreds, sheets, flakes, granules, or powder. The official specifications for agar are provided in the USP (12) and the Food Chemicals Codex (13). 

Specifications and Analysis. R%-MaHc acid that is sold in the United States meets the specifications of the Food Chemicals Codex and National Formulary, which are Hsted in Table 5 (40,41). MaHc acid is available in the following U.S. standard sieve sizes ... 

Parameter or substance Food Chemicals Codex National Formulary... 

Parameter Food Chemicals Codex National Formulatory... 

Table 4. Food Chemicals Codex Specifications for Sodium Nitrate ...

Sorbic acid and its salts are highly refined to obtain the necessary purity for use in foods. The quaUty requirements are defined by the Food Chemicals Codex (Table 3). Codistillation or recrystaUization from water, alcohoHc solutions, or acetone is used to obtain sorbic acid and potassium sorbate of a purity that passes not only the Codex requirements but is sufficient for long-term storage. Measurement of the peroxide content and heat stabiUty can further determine the presence of low amounts of impurities. The presence of isomers, other than the trans,trans form, causes instabiUty and affects the melting point. 

At least six specifications of standards for granulated sugar quaUty are appHcable ia the United States. These include Codex JUimentarius Food Chemicals Codex (ECC) (4), US. Pharmacopeia (USP) and National Formula (NE) (5), National Soft Drink Association (6), National Canners Association, and Mihtary Standard-900 for white sugar. These standards are intended to set limits on various components, including, but not necessarily limited to, polarization, invert or reducing sugar, ash, moisture, color, sulfur dioxide, arsenic, lead, and copper. 

Specifications for sulfuric acid vary rather widely. Exceptions include the federal specifications for "Sulfuric Acid, Technical" and "Sulfuric Acid, Electrolyte (for storage batteries)" and the Food Chemicals Codex specification for sulfuric acid, frequentiy called food-grade acid (although industrywide, "food-grade" is nonspecific). Very Httie has been done to estabUsh industry-wide analytical standards in the United States, except for development of the ASTM analytical methods, designated as E223-88 and summarized in Table 12. 

Determination. Various classical techniques are used for the analysis of vanillin, including colorimetric, gravimetric, spectrophotometric, and chromatographic (tic, gc, and hplc) methods. The Food Chemical s Codex (FCC) prescribes infrared spectrophotometry for identifying and testing vanillin. However, more vanillin analyses are made by either gc or hplc. 

L-Ascorbic acid biosynthesis in plants and animals as well as the chemical synthesis starts from D-glucose. The vitamin and its main derivatives, sodium ascorbate, calcium ascorbate, and ascorbyl palmitate, are officially recognized by regulatory agencies and included in compendia such as the United S fates Pharmacopeia/National Formula (USP/NF) and the Food Chemicals Codex (FCC). 

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