Cottage cheese results from a reaction between the proteins in milk and the enzyme rennin. In a milk-rennin mixture, most proteins form solid clumps called curds. The rest of them remain in a liquid state called whey. Cottage cheese manufacturers typically press much of the whey out of their product to improve its density and flavor. Cottage cheese, as a milk-based food, may be highly allergenic for some people.
Cottage Cheese Proteins
The curds in cottage cheese consist of proteins called casein. Casein accounts for 80 percent of milk protein, notes Karen Smith, Ph.D., of Wisconsin's Center for Dairy Research. Easily digestible caseins are a ready source of amino acids. Some people, however, don't fully digest the whey proteins beta-lactoglobulin and alpha-lactalbumin. The undigested beta-lactoglobulin may be the protein responsible for most milk allergies.
If you suffer from a milk protein allergy, your immune system responds to cottage cheese proteins as if they were hostile invading organisms. When the proteins enter your bloodstream, your immune system produces IgE antibodies. These antibodies signal your mast cells to release several chemical, including histamines, to fight the proteins. Histamines are responsible for your allergy symptoms.
Symptoms of a cottage cheese allergy surface between minutes and a few hours. Typical reactions typically include hives or eczema, diarrhea, nausea or other digestive problems and respiratory distress including watering eyes, sneezing, wheezing or asthma. The reaction usually subsides within 24 hours. In some cases, however, cottage cheese ingestion can lead to anaphylaxis. This life-threatening condition requires immediate medical attention. Sings of anaphylaxis include mouth, throat and airway swelling, dizziness or fainting and shock.
People sensitive to the lactose sugar in cottage cheese may mistake their symptoms for an allergic reaction. Lactose intolerance causes digestive discomfort and bloating. The condition doesn't cause an immune system response. It results from insufficient production of a lactose-digesting enzyme. Some lactose-intolerant people can eat small amounts of cottage cheese without a problem. Medical tests can determine whether a reaction to cottage cheese is allergy- or intolerance-related.
A diagnosis of milk allergy means you'll have to avoid cottage cheese and all products containing dairy proteins. These proteins show up in a range of processed food, from milk chocolate and breakfast cereals to processed meats. Food manufacturers are legally required to list milk or milk ingredients on their labels. Finding alternative sources for the calcium, Vitamin D and high-quality protein that milk provides may take some effort. Foods with soy, and many vegetables -- including broccoli and spinach -- are healthy milk replacements, according to the Cleveland Clinic website.
- Indiana Public Media Moment of Science; Miss Muffet and Her Curds and Whey; Don Glass; September 2003
- Wisconsin Center for Dairy Research; Dried Dairy Ingredients; Karen Smith, Ph.D.; May 2008
- University of Illinois; Milk Composition & Synthesis Resource Library; Milk Composition Proteins
- KidsHealth; TeensHealth from Nemours; Milk Allergy
- Mayo Clinic; What's the Difference Between a Food Intolerance and Food Allergy?; James T. C. Li, M.D
- KidsHealth; TeensHealth from Nemours; Living with Milk Allergy
- Cleveland Clinic Doiseases & Conditions; Special Diets for Food Allergies