FD&C YELLOW NO. 5, ALUMINUM LAKE

CAS: 12225-21-7 COLOR OR COLORING ADJUNCT

FD&C Yellow No. 5, Aluminum Lake is an insoluble aluminum-based pigment derived from the FD&C Yellow No. 5 dye (tartrazine) used as a color additive in foods and related products.

What It Is

FD&C Yellow No. 5, Aluminum Lake is a synthetic, insoluble pigment form of a food color additive used to impart yellow color in food and related products. It is chemically derived from the azo dye class and is based on the tartrazine dye molecule complexed with aluminum to create a stable, poorly soluble "lake" pigment form that resists migration within food matrices. The CAS number 12225-21-7 uniquely identifies this pigment, which is distinct from the free acid form of tartrazine (the water‑soluble FD&C Yellow No. 5 dye). The lake form is often used where color stability and low solubility are desired, as it binds strongly to substrates such as coating surfaces, packaging materials, or food particulates. Because this form is aluminum‑based and insoluble, it functions differently in foods than the free tartrazine sodium salt, offering a distinct functional profile in applications that require reduced bleeding or migration of color in complex formulations. FD&C Yellow No. 5, Aluminum Lake is included in regulatory inventories for food contact use and color additive certifications in the United States, and it has analogues in other regulatory regimes worldwide that recognize tartrazine and its lake derivatives as yellow food colorants subject to specified conditions of use. Regulatory references such as 21 CFR 74.1705, 82.705, and 176.180 list conditions and contexts for use of this lake pigment in foods and food contact materials under U.S. law.

How It Is Made

The production of FD&C Yellow No. 5, Aluminum Lake involves first synthesizing the parent dye, typically the azo compound tartrazine, through established dye chemistry involving diazotization and coupling reactions. The soluble dye is then combined with an aluminum salt or aluminum hydroxide under controlled conditions to form the aluminum lake complex. This process precipitates the colorant as an insoluble pigment because the aluminum binds to the dye anion, producing a lake form that is not readily soluble in water. After precipitation, the pigment is filtered, washed, and dried to yield a free‑flowing yellow powder with high color strength and long‑term stability. Producers must adhere to good manufacturing practices and quality controls to meet identity and purity criteria established by bodies such as the U.S. FDA and other regulatory authorities that monitor lake pigment production. Specifications address physical characteristics such as particle size, color intensity, and substance purity to ensure consistent performance in food applications. Because the lake form is insoluble, it reduces color migration and can provide better stability under varying conditions of pH, moisture, and storage compared with the corresponding soluble dye. The final powdered product is then supplied to food and beverage, pharmaceutical, and other industries for formulation into finished products under regulatory authorizations.

Why It Is Used In Food

FD&C Yellow No. 5, Aluminum Lake is used in foods primarily to provide a stable and visually appealing yellow color. Color additives enhance the appearance of food products, help maintain consistent color across batches, and meet consumer expectations for particular colors in familiar foods. The lake form is especially useful when manufacturers need to minimize color bleeding or migration in complex food systems, such as baked goods, confectioneries, and coatings, where a water‑soluble dye might diffuse excessively. The pigment form binds to substrates and remains fixed during processing and storage, which supports visual quality and shelf stability. Beyond simply adding color, the lake form may help match branding or flavor cues that rely on specific color cues in products. It is often selected when the formulation includes insoluble or semi‑solid components, coatings, or decorative finishes that would otherwise cause a soluble dye to spread beyond intended boundaries. The use of FD&C Yellow No. 5, Aluminum Lake therefore reflects both functional and aesthetic considerations, allowing product developers to achieve desired color results in a wide variety of food formats.

Adi Example Calculation

To illustrate how an acceptable daily intake (ADI) might be applied (using a hypothetical ADI based on tartrazine evaluations), consider a hypothetical adult weighing 70 kilograms. If an ADI expressed for the parent dye were interpreted as a certain number of milligrams per kilogram of body weight per day, the total daily intake for that individual could be calculated by multiplying body weight by the ADI number. This hypothetical calculation helps illustrate how regulators assess exposures relative to safety thresholds, though it does not imply that any specific individual should aim to consume a particular amount. In practice, food safety authorities estimate average intake of colorants from typical diets and compare those values to the ADI to confirm that exposure remains well below the level deemed acceptable by expert reviews.

Safety And Health Research

Regulatory bodies such as JECFA and EFSA have evaluated tartrazine and related compounds, including derivatives such as aluminum lakes, to assess their safety when used as food colorants. JECFA’s evaluations have historically established an acceptable daily intake range for tartrazine expressed as the parent compound, reflecting a comprehensive review of available toxicological data. The safety assessments consider endpoints such as general toxicity, carcinogenic potential, and other toxicological outcomes to derive guidance that accommodates lifetime exposure. (inchem.org Because FD&C Yellow No. 5, Aluminum Lake is a pigment form of tartrazine, regulators use data from the parent dye as part of the basis for concluding that use is acceptable under specified conditions and within defined intake thresholds. Evaluations emphasize that the lake form has minimal solubility, which influences its bioavailability compared with the free sodium salt, and extensive regulatory reviews focus on ensuring that exposures remain below the thresholds deemed safe based on rigorous assessment of animal and human data. Regulatory bodies globally maintain monitoring and re‑evaluation processes for food additives, which include periodic review of scientific literature and intake assessments to reaffirm that authorized uses remain appropriate under current scientific understanding.

Regulatory Status Worldwide

In the United States, FD&C Yellow No. 5, Aluminum Lake appears on the FDA inventory of substances listed in Title 21 of the Code of Federal Regulations, with specific citations such as 21 CFR 74.1705, 82.705, and 176.180 that identify conditions for use in food and indirect food contact applications. These regulations describe permitted uses and processing requirements for this color additive form, including preparation and labeling conditions under U.S. law. Regulatory frameworks in other regions also recognize tartrazine and its lake derivatives as color additives, often under similar numeric identifiers; for example, tartrazine itself is known in the European Union as E102 and is subject to evaluations by authorities such as EFSA. JECFA (a joint FAO/WHO expert committee) has evaluated tartrazine and related compounds and provides guidance on acceptable daily intake based on comprehensive toxicological assessments. (FDA HFP App External National and regional food safety agencies typically require manufacturers to comply with labeling and purity standards when using lake pigments in foods. In many jurisdictions, the presence of synthetic colorants must be declared on ingredient lists, and formulations must adhere to maximum use levels and good manufacturing practices defined by local food additive regulations. Consequently, FD&C Yellow No. 5, Aluminum Lake’s regulatory status reflects both its long history of evaluated use and ongoing oversight to ensure compliance with safety and labeling standards across markets.

Taste And Functional Properties

By itself, FD&C Yellow No. 5, Aluminum Lake does not contribute taste or flavor to foods, as it functions solely as a colorant rather than a flavoring agent. Its sensory properties are essentially neutral in taste, meaning that it does not impart a perceivable flavor even at typical application concentrations. Functionally, its insoluble nature distinguishes it from water‑soluble dyes; the lake form resists dissolution in aqueous phases, which helps maintain color integrity in products where moisture content or processing conditions might cause soluble dyes to migrate. The lake pigment retains its yellow hue across a range of pH levels encountered in many food products and is generally stable under common processing temperatures. Because it is a pigment rather than a dye soluble in solution, FD&C Yellow No. 5, Aluminum Lake is better suited to applications where surface color retention and minimal leaching are important. While it does not directly influence texture or rheology, its particulate nature can interact physically with food matrices at very low levels, but without altering the primary functional characteristics of the food. In practical terms, formulators rely on its stable chromatic properties to achieve consistent visual results without unintended sensory effects.

Acceptable Daily Intake Explained

An acceptable daily intake (ADI) is a level of a food additive that regulators consider safe to ingest every day over a lifetime without appreciable health risk. For tartrazine, which serves as the basis of FD&C Yellow No. 5 and its lake forms, expert evaluations by JECFA historically established an ADI expressed in terms of milligrams of the parent compound per kilogram of body weight. The ADI accounts for variability in sensitivity among consumers and uses uncertainty factors to ensure a wide margin of safety. While FD&C Yellow No. 5, Aluminum Lake itself is not always expressed with a separate ADI distinct from the parent tartrazine dye, regulators evaluate total exposure to the colorant and its derivatives against established ADI thresholds to ensure that typical dietary use remains within conservative safety margins. The ADI is not a recommended intake level but rather a guidance number indicating that daily exposure at or below this level is unlikely to pose health concerns based on current evidence. Manufacturers and safety authorities estimate exposure from food intake to ensure that typical consumption patterns do not exceed these conservative benchmarks, thereby supporting consumer safety across diverse populations.

Comparison With Similar Additives

FD&C Yellow No. 5, Aluminum Lake is one of several synthetic yellow color additives used in foods; others include FD&C Yellow No. 6 and natural colorants such as annatto extract. FD&C Yellow No. 6, like tartrazine derivatives, is another azo dye that provides an orange‑yellow hue but has distinct regulatory evaluations and use patterns compared with tartrazine. Natural colorants such as annatto extract provide yellow to orange tones from plant sources and are exempt from certification in some jurisdictions but may offer less color stability than synthetic lakes in certain applications. Compared with water‑soluble dyes, lake pigments such as FD&C Yellow No. 5, Aluminum Lake provide improved fixation to surfaces and reduced migration, which can be advantageous in coatings and decorative finishes. These differences in chemical form and functional properties help formulators select the appropriate colorant based on stability needs, regulatory constraints, and desired visual outcomes.

Common Food Applications Narrative

FD&C Yellow No. 5, Aluminum Lake is widely used in a range of food categories where stable yellow color is desired without the risk of color migration. In confectionery products, such as coated candies and decorative icings, the lake form helps maintain vibrant surface color even when exposed to moisture or heat during processing. Bakery products, including decorated cakes and pastries, benefit from the pigment's ability to stay fixed in glazes, frostings, and sugar decorations. Snack foods and cereals may also incorporate this lake pigment to enhance visual appeal in flavored or fruit‑themed products. Ready‑to‑eat dessert products, such as gelatin snacks and puddings with decorative layers, use the lake form to maintain distinct color boundaries between layers. Beverage powders and drink mixes can include lake pigments in their coatings or encapsulated forms to ensure that the dry mix retains a consistent appearance before reconstitution. Even savory products with color cues—such as certain sauces or seasoned coatings—may use FD&C Yellow No. 5, Aluminum Lake to achieve color targets that inform consumer perception of flavor. Across these applications, the pigment form provides a functional advantage when formulation demands color stability during manufacturing, packaging, and shelf life, supporting product aesthetics and consumer expectations.

Safety & Regulations

FDA

  • Notes: Listing in CFR indicates authorized use under specified conditions but does not itself confirm an approval status without contextual regulatory text.
  • Regulation: 21 CFR 74.1705

EFSA

  • Notes: EFSA evaluation applies to tartrazine (E102) but specific lake form numeric ADI not explicitly shown on a d EFSA link.

JECFA

  • Notes: JECFA established an ADI range historically; the specific year of this evaluation is not explicitly shown on the d entry.
  • Ins Number: 102
  • Adi Display: 0-7.5 mg/kg bw
  • Adi Mg Per Kg: 7.5

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