To the layperson, "casein" and "sodium caseinate" are essentially the same products. It's helpful to know that casein is naturally found in milk, while sodium caseinate is derived from casein as a protein supplement, but many people still use them interchangeably.
Casein is the main protein in milk. A form of it, sodium caseinate, is a milk derivative added to other products for nutrition or texture, or sold as a nutritional supplement.
Creating Sodium Caseinate
"Curds and whey" isn't just an expression from a nursery rhyme. Separating milk into solids (curds) and the leftover liquid (whey) enables dairy producers to make everything from cottage cheese to queso blanco.
Creating curds is also the first step in making sodium caseinate. Milk is curdled by adding an acidic material to the liquid. Artisans and home cheesemakers can use lemon juice or vinegar. Commercial dairy manufacturers use rennet, an animal-derived material consisting of enzymes that spur the curdling process.
In order to extract the casein protein from resulting curds, the curds get treated with an alkali, and are then dried. One common alkali is sodium, and the product resulting from its use is known as sodium caseinate.
Sodium caseinate is about 90 percent protein. It's considered an ideal form of casein, because it can dissolve easily when mixed with a liquid.
This quality makes it useful for adding to food products, both for structure, and to improve the nutritional content of low-fat dairy products. Sodium caseinate is also useful as a nutritional supplement, either in a premixed liquid protein blend, or for people who want to dissolve sodium caseinate into their own beverages and foods.
Using a Sodium Caseinate Supplement
When it comes to adding protein powder to their daily diet, many people find themselves choosing between whey protein and casein protein, also known as sodium caseinate. Each has its own pros and cons, notes the International Food Information Council Foundation.
Like whey, casein proteins can help build muscle mass, especially when combined with strength training. The chemical structure of casein is bubble-like, which allows for a slow release of its amino acids into the bloodstream. This gradual protein boost "feeds" muscles in a sustained way, over the course of several hours, rather than in one quick burst. Consider using casein powder prior to working out, in order to supply muscles with the nutrients they need.
Sodium caseinate, and other forms of casein, may also be good to take before going to bed. During time in bed, muscles repair themselves and begin to rebuild from daytime workouts, especially those involving strength training.
There are a number of ways to add sodium caseinate or other protein powders to your daily diet. Pick up some "muscle milk," which is premixed and ready to drink. Alternately, add protein powder to your smoothies, morning oatmeal or late afternoon yogurt snack.
There may be times when you’ll prefer whey to casein protein as a supplement, notes ACE. Because whey protein enters your bloodstream more rapidly than sodium caseinate, and is a good source of muscle-supporting amino acids, whey powders may be helpful just after strength training to support immediate muscle growth and recovery.
Considering the Allergy Factor
Not everyone is searching for sodium caseinate as a way to add nutrients to their diet. In fact, it's helpful to read labels carefully if you have any milk-related allergies. Some families may buy products they believe to be dairy-free, without realizing that these might include milk derivatives such as sodium caseinate, notes the Asthma and Allergy Foundation of America.
People who are lactose intolerant lack the ability to break down lactose, which is the sugar content of milk. These sugars move into your colon, instead of being absorbed into the bloodstream. Some of the classic signs of lactose intolerance include stomach pain, bloating, gas and diarrhea.
You might be surprised how often milk derivatives are used in the food industry. Sodium caseinate adds extra nutrition to certain products, such as protein shakes, but also improves the texture of processed meats, and thickens creamy products. The natural white color of sodium caseinate also helps brighten certain substances, which is why it's a popular additive for products such as coffee creamers.
If you suspect you have any sort of milk allergy or intolerance, watching for sodium caseinate on labels is helpful. The FDA warns that it may also appear listed only as "milk derivative" or "caseinate."
Choosing Your Protein Sources
Talking to your doctor or nutritionist before adding a nutritional supplement to your health plan is always a good idea. In the case of sodium caseinate, it's important to assess how much protein you get in your diet, before adding more through sodium caseinate or whey protein powders.
According to the Mayo Clinic, many Americans already get more protein than they need. In fact, some people mistakenly place too much faith in the ability of protein alone to build muscle, ignoring the efficacy of strength training.
The danger when ingesting too much protein is that, if you don't utilize all of it while working out, it will be stored as body fat. Even if all of your dietary protein is low in saturated fat, adding protein supplements on top of dietary fat can potentially tax the kidneys, the Mayo Clinic warns.
A woman who weighs about 130 pounds needs roughly 50 grams of protein per day, according to the standard guideline of 0.8 grams of protein per 1 kilogram of body weight. A serving of protein powder containing casein can contain about 40 grams of protein, notes the University of Washington Nutritional Sciences Program. Modifying that serving may be helpful if you already get average or above-average amounts of protein through your diet.
It's also important to remember the "sodium" component of sodium caseinate. A product such as "muscle milk," which contains sodium caseinate, can contain as much as 430 milligrams of sodium, the University of Washington points out.
Read more: Is There Cheese Without Casein or Lactose?
Need Dairy-Free Alternatives?
There's no getting around the fact that sodium caseinate, for all its benefits, is a milk derivative. If you're a vegan, or suffer from milk allergies, other forms of protein additive and high-protein foods are available.
Consider adding powered "milk" from dairy-free sources such as rice milk, nut, or soy milk powders. Blend them into smoothies, oatmeal and other foods, just as you would sodium caseinate and other protein powders. Check the label, however, to ensure these vegan products don't contain words like "casein," "whey powder" or "milk derivative."
Your best option, however, is to eat a diet rich in plant-based whole foods that are high in protein. Cooked beans provide 7 to 9 grams of protein per serving. Seeds, nuts and nut butters range from 4 to 9 grams protein per serving.
Choose grains that naturally contain protein, such as wheat berries, quinoa and kamut, which deliver 4 to 6 grams of protein in a serving. Soy-based foods like milk, tofu and tempeh provide 8 to 16 grams of protein. Even vegetables like spinach, artichokes and peas deliver 3 to 5 grams of protein in a single serving.
- Journal of Dairy Science: "Addition of Sodium Caseinate to Skim Milk"
- Dairy Management Inc.: "Whey vs. Casein: What Makes These Proteins Different?"
- Asthma and Allergy Foundation of America: "Milk Allergy"
- Mayo Clinic: "Are You Getting Too Much Protein?"
- University of Washington Nutritional Sciences Program: "Protein Powder"
- Academy of Nutrition and Dietetics: Vegetarian Nutrition: "Protein in Vegetarian and Vegan Diets"
- International Food Information Council Foundation: "A Primer on Protein Powders"
- Nutrition & Metabolism: "Milk Protein for Improved Metabolic Health"