Legal Standards for Skim Milk, Casein, and Caseinates

Skim milk, casein, and caseinates are among the most widely used dairy products – both in households and in the food manufacturing industry. But how do regulators ensure that these products are safe, consistent, and free from adulteration? The answer lies in a set of legal standards defined by Indian and international regulatory bodies. In India, the Food Safety and Standards Authority of India (FSSAI) – which has replaced the earlier Prevention of Food Adulteration (PFA) Act framework – along with the Bureau of Indian Standards (BIS) and the Codex Alimentarius Commission, set the benchmarks that manufacturers must follow. Let’s break down what these standards actually say.

What is skimmed milk under Indian law? 🔗

Under the erstwhile PFA Act – and now continued through FSSAI regulations – skimmed milk is defined as a product prepared from milk by mechanically removing almost all the milk fat. The two key compositional requirements are straightforward: it must contain no more than 0.5% milk fat and a minimum of 8.5% milk solids-not-fat (SNF). These parameters ensure that while the fat has been taken out, the nutritional core of the milk – proteins, lactose, vitamins, and minerals – remains intact.

This distinction matters because skimmed milk is not the same as diluted or watered-down milk. When water is added to milk, it reduces everything – fat, protein, calcium, and other nutrients. Professionally processed skimmed milk, on the other hand, uses centrifugal separation to remove only the fat layer while preserving the nutrient-rich portion.

FSSAI classification of milk types 🔗

To put skimmed milk in context, the FSSAI classifies milk into several categories based on fat and SNF content. Full cream milk requires a minimum of 6.0% fat and 9.0% SNF. Standardized milk sits at 4.5% fat and 8.5% SNF. Toned milk has 3.0% fat and 8.5% SNF, while double toned milk contains 1.5% fat and 9.0% SNF. Skimmed milk, with its maximum of 0.5% fat, is the leanest option in this spectrum. These categories apply uniformly across India and are applicable to milk made from cow, buffalo, or a combination of species.

FSSAI also requires that the total urea content in milk must not exceed 700 ppm. All milk types, including skimmed milk, must comply with the contaminant and toxin limits specified under the Food Safety and Standards (Contaminants, Toxins and Residues) Regulations, 2011. Labelling requirements mandate clear declaration of the type of milk and its fat content on pre-packaged products.

Why there are no PFA standards for casein and caseinates 🔗

Here’s something many students find surprising: the PFA Act does not define casein or caseinates, and there are no specific PFA standards for these products in India. This doesn’t mean they are unregulated – it simply means that India’s older food adulteration law did not include a dedicated section covering the compositional and quality requirements of casein and caseinates.

So where do the standards come from? Two primary sources fill this gap: the Bureau of Indian Standards (BIS) at the national level and the Codex Alimentarius Commission (jointly run by the FAO and WHO) at the international level. Additionally, the European Union’s Directive 2015/2203 provides a well-documented regulatory framework that many exporters and importers reference.

BIS standards for edible casein products 🔗

The Bureau of Indian Standards published IS 1167 : 2021, titled “Edible Casein Products – Specification.” This standard covers three distinct product categories: edible acid casein, edible rennet casein, and edible caseinate. It lays down requirements for composition, quality, and testing methods for each of these products when they are intended for human consumption or further food processing.

BIS standards align closely with international benchmarks, particularly the Codex Alimentarius standard (CXS 290-1995). They set limits for moisture, fat, protein, ash, and lactose content – all of which are critical indicators of product quality and safety. The standard also addresses microbiological requirements, ensuring that casein products are free from harmful pathogens before they reach the consumer or food manufacturer.

What is edible acid casein? 🔗

Edible acid casein is produced by precipitating the protein from skimmed milk using food-grade acids – such as lactic acid, hydrochloric acid, sulphuric acid, or citric acid. The resulting coagulum is then separated, washed, and dried. It is commonly used in food manufacturing as a protein supplement and in applications like cheese analogues and bakery products.

What is edible rennet casein? 🔗

Edible rennet casein follows a similar process, except the coagulation is achieved through the action of rennet or other coagulating enzymes rather than acid. The coagulum is separated from whey, washed to remove residual lactose and minerals, and then dried. Rennet casein typically has a higher ash content (minimum 7.5%) compared to acid casein, because the enzymatic process retains more mineral matter – particularly calcium and phosphorus.

What are edible caseinates? 🔗

Edible caseinates are produced by treating acid casein or casein curd with neutralizing agents – such as sodium hydroxide, calcium hydroxide, or potassium hydroxide – followed by drying. The resulting product is named based on the cation used: sodium caseinate, calcium caseinate, potassium caseinate, and so on. Caseinates are known for their excellent solubility (except calcium caseinate) and functional properties like emulsification and foaming, making them highly versatile in the food industry.

Codex Alimentarius standards for edible casein products 🔗

The Codex Standard CXS 290-1995 (originally adopted in 1995 and revised in 2001, with amendments in 2010, 2013, and 2014) is the most widely referenced international standard for edible casein products. It provides detailed compositional requirements for all three categories.

Compositional requirements under Codex 🔗

For edible acid casein, the Codex standard requires a minimum milk protein content of 90% on a dry matter basis, with at least 95% of that protein being casein. The maximum moisture allowed is 12%, maximum milk fat is 2%, maximum lactose is 1%, and the maximum ash content is capped at 2.5%. There is also a limit on free acidity – no more than 0.27 ml of 0.1N NaOH per gram.

For edible rennet casein, the minimum protein in dry matter drops slightly to 84%, reflecting the higher mineral retention in this product. The maximum moisture and fat limits remain the same at 12% and 2%, respectively. However, the ash content has a minimum requirement of 7.5% (unlike acid casein, where it’s a maximum), because the enzymatic coagulation naturally binds more minerals. Maximum lactose is still 1%.

For edible caseinates, the protein minimum is 88% on a dry matter basis. The key difference here is a stricter moisture limit of just 8%, along with a maximum fat of 2% and maximum lactose of 1%. The pH must not exceed 8.0. No free acidity or ash limits are specified for caseinates, since the neutralization step fundamentally changes the mineral profile.

Physical appearance and quality 🔗

The Codex standard also specifies that all edible casein products should be white to pale cream in colour, free from lumps that don’t break under slight pressure, and should have no offensive flavours or odours. Heavy metal limits are set at a maximum of 5 mg/kg for copper and 20 mg/kg for iron (50 mg/kg for roller-dried caseinates).

EU standards for caseins and caseinates 🔗

The European Union regulates caseins and caseinates through Directive (EU) 2015/2203, which replaced the older Council Directive 83/417/EEC. This directive was updated to align with the Codex standard and modernize terminology. It applies specifically to caseins and caseinates intended for human consumption.

The EU compositional standards closely mirror the Codex requirements. For edible acid casein, the maximum moisture is 12%, minimum protein on dried extract is 90%, maximum fat is 2%, and maximum ash is 2.5%. For edible rennet casein, the protein minimum is 84%, with a minimum ash of 7.5%. Edible caseinates must have no more than 8% moisture, minimum 88% protein, maximum 2% fat, and a pH range of 6.0 to 8.0.

The EU directive also mandates specific labelling requirements: the product name, net quantity, manufacturer details, country of origin for imports, and lot identification must all appear clearly on the packaging. For caseinates, the specific cation (sodium, calcium, potassium, etc.) must always be declared.

Why these standards matter for the dairy industry 🔗

Legal standards for skim milk, casein, and caseinates serve multiple purposes. First, they protect consumers from adulteration and substandard products. Second, they create a level playing field for manufacturers, ensuring that everyone in the market meets the same quality benchmarks. Third, they facilitate international trade – a manufacturer in India producing casein for export to Europe needs to comply with both BIS and EU/Codex standards.

For food manufacturers, casein and caseinates are functional ingredients used in everything from processed cheese and coffee creamers to protein bars and infant formula. If the raw material doesn’t meet quality standards – say, it has excess moisture or low protein content – the end product will be compromised. Standards act as a quality assurance checkpoint at every stage of the supply chain.

The role of FSSAI going forward 🔗

In recent years, FSSAI has been consolidating India’s food safety regulations and aligning them with international standards. A significant change came in 2024, when FSSAI removed the requirement for separate BIS/ISI certification marks for several dairy products – including skimmed milk powder and sweetened condensed milk – streamlining regulatory compliance so that FSSAI certification alone is sufficient. This simplification reduces costs and speeds up market access for food businesses.

While casein and caseinates still lack a dedicated FSSAI product standard, the BIS specification (IS 1167 : 2021) and the Codex standard together provide a robust regulatory framework. Any casein or caseinate product marketed for food use in India is expected to meet these benchmarks, and FSSAI’s general provisions on contaminants, hygiene, and labelling still apply.

Key takeaways 🔗

Skimmed milk has a clear legal definition in India – maximum 0.5% fat, minimum 8.5% SNF – enforced through FSSAI. Casein and caseinates, while not defined under the old PFA Act, are regulated through BIS (IS 1167 : 2021) and the international Codex standard (CXS 290-1995). These standards specify limits for moisture, fat, protein, ash, lactose, and contaminants. The EU Directive 2015/2203 provides an additional reference point, particularly relevant for export-oriented manufacturers. Together, these frameworks ensure that whether you’re buying a packet of skim milk at a local store or sourcing sodium caseinate for a food processing plant, the product meets defined safety and quality criteria.

What do you think? With India being the world’s largest milk producer, should FSSAI introduce a dedicated, comprehensive standard specifically for casein and caseinates – rather than relying on BIS and Codex? And how might stricter enforcement of skimmed milk standards help address the widespread issue of milk adulteration in unorganized markets?

References

1. https://www.fssai.gov.in/upload/uploadfiles/files/Chapter%202_1%20(Dairy%20products%20and%20analogues).pdf
2. https://www.fao.org/input/download/standards/185/CXS_290e.pdf
3. https://www.fssai.gov.in/upload/uploadfiles/files/Compendium_Food_Additives_Regulations_20_12_2022.pdf
4. https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32015L2203
5. https://www.fssai.gov.in/
6. https://edairy.net/agmark-bis-isi-no-longer-needed/