February 2016 Issue

What's Trending in the Dairy Aisle?
By David Yeager
Today's Dietitian
Vol. 18 No. 2 P. 30

As fluid milk sales continue to wane, yogurt, kefir, and cottage cheese products gain in popularity as consumers adapt them to their 21st century lifestyles.

High in protein, calcium, potassium, and, in some cases, vitamin D, dairy products can be a valuable source of essential vitamins, minerals, and nutrients. But many Americans aren't benefiting from these foods as much as they could be. Although the 2015 Dietary Guidelines for Americans recommend 2 cup-equivalents of dairy products per day for children aged 2 to 3, 2.5 cup-equivalents for children aged 4 to 8, and 3 cup-equivalents for people aged 8 and up, American per capita dairy consumption has been 1.5 cup-equivalents per day for many years.1 This rate has remained unchanged, despite Americans' increasing consumption of cheese.1

The decades-long drop in US fluid milk consumption may be part of the reason dairy products play a smaller role in American diets than the guidelines recommend. Since 1970, overall fluid milk consumption has declined from .096 cup-equivalents to .061 cup-equivalents per person.1 Many people choose to completely avoid dairy products due to lactose intolerance, maldigestion, or lifestyle choices, but those who aren't dairy averse may find that products other than milk can play a role in their diets.

According to data released in June 2015, yogurt, kefir, and cottage cheese, among other dairy foods, are showing strong sales growth.2 Although each of these products has an ancient tradition, consumers seem to be adapting them to 21st century lifestyles. This shift may help fill a void in Americans' diets.

"This is a way of filling in a nutrient gap," says Isabel Maples, MEd, RD, a food safety expert and spokesperson for the Academy of Nutrition and Dietetics (the Academy). "One of the things that researchers do when they develop the Dietary Guidelines is to look at consumption patterns, based on NHANES [National Health and Nutrition Examination Survey] and other surveys, and evaluate different foods to find out how dietary changes affect nutrient consumption. And they've found that if people get three or more servings a day of dairy, they are more likely to get some of the critical nutrients they may otherwise be missing. The last couple of Dietary Guidelines committees have identified vitamin D, potassium, calcium, and fiber as nutrients of concern. Dairy foods are the No. 1 food source of calcium, potassium, and vitamin D."

Got Enzymes?
One problem with milk, as our distant ancestors discovered, is that it tends to spoil quickly unless it's kept cold, which is a major drawback when refrigeration isn't available. As far back as 5000 BC, and possibly as early as 10,000 BC, ancient man discovered that converting milk to yogurt has a preservative effect.3 It has been surmised that the first yogurts were produced in the goatskin bags of Middle Eastern herdsmen.3 The combination of intestinal enzymes from the bags, the warmth of the climate, and the undulations of the camels that the herdsmen rode may have been just the conditions necessary to turn milk into yogurt.3 Whatever the true origin of yogurt may be, by 2000 BC, people throughout the ancient world were eating yogurt.3

The word yogurt comes from the Turkish word "yoğurmak."3 The oldest written mentions of it come from Pliny the Elder, who sang its praises, and possibly the Bible; some translators believe that references to "the land of milk and honey" in the Bible refer to yogurt.3 Many folkloric medicinal properties have been ascribed to yogurt, such as providing relief from diarrhea or sunburn, and Genghis Khan is said to have believed that it fortified his men with strength and bravery.3

So yogurt has been around for a long time. What does it offer today's consumers?

"Today's consumers love choice, and they don't necessarily want to be told that they have to drink milk with meals," Maples says. "Today's yogurts are very convenient."

Buying yogurt in one-quart tubs may save a little money, Maples says, but individually packaged yogurts are portable and versatile. Along with numerous flavors, there are many styles from which to choose. One popular style is Greek yogurt, which is put through a strainer and has less water content, making it thicker. Greek yogurt is higher in protein than regular yogurt and has less calcium and potassium, although its calcium and potassium contents are higher than many other foods. A 227 g (8 oz) serving of plain, low-fat Greek yogurt has 166 kcal, 23 g protein, 8 g sugar, 261 mg calcium, and 320 mg potassium.4 The same serving size of plain, low-fat yogurt has 143 kcal, 12 g protein, 16 g sugar, 415 mg calcium, and 531 mg potassium.5

Skyr, an Icelandic yogurt product made by MS Iceland Dairies, is made with skim milk but has a thicker consistency than regular or Greek yogurt.6 It has, depending on the variety, 110 to 160 kcal, 16 to 19 g protein, and, for flavored varieties, roughly 19 g sugar per 6-oz (170 g) serving. It's available in plain, blueberry, strawberry, and vanilla in select retailers in the northeastern United States. Smári yogurt, the only certified organic Icelandic yogurt sold in the United States, contains 14 to 17 g protein per 5-oz serving, and is available in pure (whole milk and nonfat), vanilla (whole milk and nonfat), coconut (0% milkfat), peach (nonfat), strawberry (nonfat), and blueberry (nonfat) varieties. Tarte Foods produces Tarte Asian Yogurt sold at select US retailers. Varieties include Strawberry & Guanabana, Original, Acai & Blueberry, Mango & Coconut, Pomegranate & Goji, and Green Tea & Honey. A 6-oz (170 g) serving has 110 kcal, 12 g protein, 320 to 340 g potassium, and 13 to 15 g sugar, depending on the flavor.

Although some may be concerned about the sugar content of some yogurts, Maples says it's better to consume those sugars in nutrient-rich foods like yogurt than in foods with less nutritional value.

Nutrient concentrations may not be the only reason to eat more yogurt. In the early 1900s, Bulgarian physician and microbiologist Stamen Grigorov, then a student, discovered a strain of Bacillus that causes milk fermentation and produces yogurt.3 The strain is known as Lactobacillus bulgaricus and often is used today in yogurt production.3 L. bulgaricus and other microbes used to make fermented dairy products often are called probiotics, and a growing body of evidence suggests they can be beneficial to human health. Some studies have found that certain strains of probiotics, such as L. casei and L. rhamnosus, can help alleviate symptoms of diarrhea, irritable bowel syndrome, and lactose intolerance.7-10 Further study is needed to determine whether probiotics confer any additional benefits.

A large area of growth in recent yogurt sales has been in fermented drinks.2 Between May 2014 and May 2015, dollar sales of yogurt and kefir drinks rose 19.4%.2 Kefir, like yogurt, is made from fermented milk. It's popular in Russia and the Caucasus region, and likely originated in that area.11 Marco Polo supposedly mentioned kefir in the tale of his journey to the East.11

Kefir's fermentation process is a little different from yogurt, in that it's fermented with special "grains," a culture of fermentation bacteria and yeast that gives it a slightly yeasty and slightly more sour taste than yogurt.12 Although they're referred to as grains, these cultures don't contain gluten. According to tradition, the Prophet Mohammed gave the magical grains to the people who lived on the north slopes of the Caucasus Mountains and taught them how to make kefir.11 As the story goes, the people guarded their secret closely for centuries, until some enterprising Russians figured out how to procure some of the grains, and an industry was born.11 Kefir may not have the perfect flavor or texture to replace milk, but its popularity is on the rise in the United States.

Yogurt and kefir drinks come in many varieties and flavors. Companies such as Lifeway, Trader Joe's, The Greek Gods, Ronnybrook, Stonyfield, Green Valley, Siggi's, Traderspoint, Evolve, and Latta make versions of yogurt and/or kefir drinks with different fruits, flavorings, and textures. A 227-g serving of vanilla yogurt mixed with low-fat milk and low-calorie sweetener contains 195 kcal, 11 g protein, 12 g sugar, 388 mg calcium, and 497 mg potassium.13 By comparison, a 227-g serving of Lifeway's plain, low-fat kefir has 93 kcal, 9 g protein, 10 g sugar, 295 mg calcium, 372 mg potassium, and 93 IU vitamin D.14 Some, but not all, yogurt and kefir drinks add vitamin D in the processing of the drinks.

Curds and Whey
Another growth area for dairy has been cottage cheese.2 Dollar sales between May 2014 and May 2015 increased 10%.2 Cottage cheese is an uncured type of cheese that's made by curdling milk and draining most of the liquid, which is called whey.15 The curd isn't pressed, however, so some of the whey remains and the curd retains a sweet flavor.16 There are two types of cottage cheese—small curd and large curd. Large curd cottage cheese relies on the addition of rennet, an enzyme that speeds up the curdling but keeps the curd from breaking up.15

The ancient Egyptians, Greeks, and Romans ate cottage cheese.15 The term "cottage cheese" is more recent and is believed to have originated with American settlers who used the leftover milk from butter making to produce the cheese in their cottages.16 It can be eaten by itself, just the way Little Miss Muffet enjoyed it before she was so rudely interrupted. A 227-g serving of 2% milk fat cottage cheese has 184 kcal, 24 g protein, 9 g sugar, 252 mg calcium, and 284 mg potassium.17

Cottage cheese also can be mixed with other ingredients, such as canned or fresh fruit, chopped vegetables, and greens to create a nutrient-rich meal. People who are familiar with Pennsylvania Dutch country may know the culinary delight of mixing cottage cheese with apple butter. (Sprinkle a little wheat germ on top for some additional texture and fiber.) Maples recommends using cottage cheese instead of salad dressing at the salad bar to add some protein, texture, and flavor. It also works well in smoothies.

"Smoothies are easy, portable, and convenient," says Sonya Angelone, MS, RDN, CLT, a certified LEAP (lifestyle eating and performance) therapist and lifestyle counselor and a spokesperson for the Academy. "You can make them very nutrient dense. You can use yogurt or kefir or milk as a base and add fruits or whatever you like. I add cottage cheese to smoothies for protein, and it sounds maybe a little strange, but if you try it, you won't even know there's cottage cheese in it. The cottage cheese helps thicken the smoothie. It also adds protein without having to rely on a protein powder."

In addition, there are many other ways to use yogurt or cottage cheese, Angelone says. Either can be mixed with hummus or avocado to make a creamier version of guacamole. She also recommends plain yogurt as a base for tuna salad or a stand-in for sour cream. Adding spices or herbs can turn it into a delicious dip. Angelone says yogurt also can be used as a base for sauces, but it doesn't heat well, so boiling is not recommended. She says cottage cheese can be added to tomato sauce to add protein without adding meat or substituted for ricotta cheese in stuffed shells in which she often adds chopped spinach. She also likes to eat her yogurt or cottage cheese with berries.

With the many dairy and fortified nondairy products available, clients can get the necessary nutrients they need to promote optimal health, Angelone says. For modern Americans, the convenient, individual serving size packaging of yogurt, kefir, and cottage cheese makes it all the more easy to help close some of the nutrient gaps in their diets. With a little imagination, creativity, and a willingness to experiment with various recipes, there are many ways to incorporate dairy into a healthful diet.

— David Yeager is a freelance writer and editor based in southeastern Pennsylvania.

References
1. Stewart H, Dong D, Carlson A. Why are Americans consuming less fluid milk?: a look at generational differences in intake frequency. United States Department of Agriculture, Economic Research Service website. http://www.ers.usda.gov/media/1118789/err149.pdf. Published May 2013. Accessed December 15, 2015.

2. Watson E. Who are the winners and losers in the US dairy products market? FoodNavigator-USA website. http://www.foodnavigator-usa.com/Markets/Who-are-the-winners-and-losers-in-the-US-dairy-products-market. Updated June 24, 2015. Accessed December 15, 2015.

3. The complete history of yogurt-making. Yogurt in Nutrition website. http://www.yogurtinnutrition.com/complete-history-yogurt-making/. Published January 27, 2015. Accessed December 15, 2015.

4. Basic report: 01287, yogurt, Greek, plain, lowfat. United States Department of Agriculture, Agricultural Research Service website. http://ndb.nal.usda.gov/ndb/foods/show/235?fgcd=&manu=&lfacet=&format=&count=&max=35&offset=210&sort=&qlookup. Accessed December 16, 2015.

5. Basic report: 01117, yogurt, plain, low fat, 12 grams protein per 8 ounce. United States Department of Agriculture, Agricultural Research Service website. http://ndb.nal.usda.gov/ndb/foods/show/106?fgcd=&manu=&lfacet=&format=&count=&max=35&offset=105&sort=&qlookup. Accessed December 16, 2015.

6. Skyr: Original Icelandic Skyr Cultures. MS Iceland Dairies website. http://www.skyriceland.com/skyr.is-products. Accessed December 19, 2015.

7. Collado MC, Isolauri E, Salminen S, Sanz Y. The impact of probiotic on gut health. Curr Drug Metab. 2009;10(1):68-78.

8. Ouwehand AC, Salminen S, Isolauri E. Probiotics: an overview of beneficial effects. Antonie Van Leeuwenhoek. 2002;82(1-4):279-289.

9. de Vrese M, Schrezenmeir J. Probiotics, prebiotics, and synbiotics. Adv Biochem Eng Biotechnol. 2008;111:1-66.

10. Composition of milk kefir grains: bacteria & yeasts. Cultures for Health website.
http://www.culturesforhealth.com/milk-kefir-grains-composition-bacteria-yeast. Accessed December 19, 2015.

11. History of kefir. Kefir: Yoghurt for Life website. http://www.kefir.biz/history.htm. Accessed December 15, 2015.

12. What is the difference between yogurt and kefir? Cultures for Health website. http://www.culturesforhealth.com/difference-between-yogurt-kefir. Accessed December 15, 2015.

13. Basic report: 01231, yogurt, vanilla flavor, lowfat milk, sweetened with low calorie sweetener. United States Department of Agriculture, Agricultural Research Service website. http://ndb.nal.usda.gov/ndb/foods/show/199?fgcd=&manu=&lfacet=&format=&count=&max=35&offset=175&sort=&qlookup. Accessed December 16, 2015.

14. Basic report: 01289, kefir, lowfat, plain, LIFEWAY. United States Department of Agriculture, Agricultural Research Service website. http://ndb.nal.usda.gov/ndb/foods/show/236?fgcd=&manu=&lfacet=&format=&count=&max=35&offset=&sort=&qlookup=kefir. Accessed December 16, 2015.

15. Cottage cheese facts. iGrow website. http://igrow.org/livestock/dairy/cottage-cheese-facts/. Published May 27, 2013. Accessed December 15, 2015.

16. Cottage cheese. Cheese.com website. http://www.cheese.com/cottage-cheese/. Accessed December 15, 2015.

17. Basic report: 01015, cheese, cottage, lowfat, 2% milkfat. United States Department of Agriculture, Agricultural Research Service website. http://ndb.nal.usda.gov/ndb/foods/show/15?fgcd=&manu=&lfacet=&format=&count=&max=35&offset=0&sort=&qlookup. Accessed December 16, 2015.

[Recipe]

Sonya's High-Protein Smoothie

Ingredients
1 cup milk of choice (dairy, nondairy, kefir)
1/2 frozen banana
1/3 cup berries (use fresh banana if using frozen berries)
1/2 cup cottage cheese
Pinch of cinnamon, optional

Directions
Blend all ingredients together until well combined.

— Recipe courtesy of Sonya Angelone, MS, RDN, CLT

Nutrient Analysis per serving
Calories: 250; Total fat: 4 g; Sat fat: 2 g; Trans fat: 0 g; Cholesterol: 17 mg; Sodium: 480 mg (or 190 mg if choosing a no-salt-added brand of cottage cheese); Total carbohydrate: 36 g; Dietary fiber: 4 g; Sugar: 25 g; Protein: 23 g