Manufacturers have promoted the calcium and vitamin D content of their dairy-based products for years. More reason to do so, and also increase the fortification level, may be found in potential new consumption guidance levels and recently launched ingredient systems.
Adequate daily intake levels of vitamin D range from 200 International Units (I.U.) to 600 I.U., depending on a person’s age, according to the Food and Nutrition Board, a unit of the Institute of Medicine.
Nutritional studies are showing the levels of vitamin D, especially among the elderly, are not high enough, said Dr. Lloyd E. Metzger, Ph.D., director of the Midwest Dairy Foods Research Center in St. Paul, Minn. The researchers sought to determine the feasibility of adding 250 I.U. of vitamin D per serving to 2% milk, 2% chocolate milk, low-fat strawberry yogurt and process cheese.
The researchers concluded, "Vitamin D fortification was feasible and stable over all products’ shelf lives at 250 I.U. of vitamin D per serving."
The researchers chose 250 I.U. because it is 25% of 1,000 I.U., a level that vitamin D daily intake guidance might rise to, Dr. Metzger said. Currently, milk sold at retail has about 100 I.U. per serving, he added.
Vitamin D addition to milk is optional, but if it is added, vitamin D must be present at levels required in the standard of identity, or 400 I.U. per quart.
Formulators should make certain vitamin D is incorporated evenly in dairy products, Dr. Metzger said.
If formulators are batching the product, they should use a water-soluble form, Dr. Metzger said.
"You need to make sure there are no flavor defects at higher levels of fortification," he said.
Another study examined the potential of adding vitamin D to cheese. Eighty adults were randomized and given weekly servings of fortified cheddar cheese, fortified low-fat cheese, a liquid vitamin D supplement taken with food or without food, placebo cheddar cheese and a placebo supplement. The mean increases in the vitamin D-treated groups did not differ over eight weeks.
"These data demonstrate that vitamin D is equally bioavailable from fortified hard cheeses and supplements, making cheese suitable for vitamin D fortification," said the researchers from the University of Toronto; Mount Sinai Hospital in Toronto; the National Research Centre in Cairo, Egypt; the University of Saskatchewan in Saskatoon and Ryerson University in Toronto. Results appeared in the July issue of The Journal of Nutrition.
Ingredient suppliers also are promoting ways to add more calcium to dairy products. The A.I. for calcium ranges from 210 mg per day to 1,300 mg per day, depending on a person’s age, according to the Food and Nutrition Board. The calcium intake levels for both adults and children are a concern, adds the 2005 Dietary Guidelines for Americans. Thus, opportunity exists for increased calcium inclusion.
Independent sensory tests revealed Aquamin calcified mineral source may boost the calcium content in a range of dairy applications without affecting taste or texture, said GTC Nutrition, Golden, Colo. GTC Nutrition offers Aquamin, a mineral ingredient derived from seaweed (Lithothamnion Calcareum). Nizo Food Research, B.V. assessed the impact of Aquamin S and Aquamin Soluble in dairy products. The study involved milk and yogurt drinks fortified with 25% calcium and stirred yogurt products fortified with 40% calcium.
Formulators working with acidified dairy drinks may use Puracal QSynergy, a mixture of calcium lactate and citrate, according to Purac. The ingredient contains 19% bioavailable calcium and is more soluble than calcium citrate and calcium phosphate, according to Purac.
Innophos, Cranbury, N.J., offers VersaCal MP, a source of calcium and phosphorous that may be added to cottage cheese, yogurt and skim milk.