Butter is made from fresh or sweet cream (as opposed to sour cream) by churning and consists of butterfat, milk proteins, and water.  Salt, flavorings, and preservatives are sometimes added for flavor and prolonged shelf life.   Butter remains a solid when refrigerated, but softens to a spreadable consistency at room temperature, and melts to a thin liquid consistency at higher temperatures90–95 °F).   Cultured butter is unsalted butter made using a traditional European method in which a live culture is incubated into the cream during churning to increase flavor.  Natural food stores will typically offer salted and unsalted butter made from the milk of grass-fed, sustainably raised cows or from certified organic milk.  Certified organic butter will carry the USDA Organic seal. 

For a time, when the medical community was concerned about cholesterol, butter was considered an unhealthy fat as compared to margarine.  However, in recent years, science has recognized that only certain kinds of cholesterol in certain amounts are bad and science-focused the negative impacts of hydrogenated vegetable oil used in margarines.  Now butter is once again thought of as a healthier choice compared to margarine.

Yogurt, Kefir, and the Benefits of Fermented Milk

Yogurt is fermented milk.   Yogurt is made by inserting a starter culture of “friendly” bacteria, usually, Streptococcus thermophilus and Lactobacillus bulgaricus, into milk.  The milk is then incubated at approximately 110°F until the milk is coagulated by bacterial produced lactic acid and becomes firm.   The thickened milk results in a creamy texture, adding a tangy, slightly astringent flavor.  In commercial manufacturing, the friendly bacteria is added, but if you were to heat raw milk and keep it at about 100°F for a few hours, it would naturally turn into yogurt.  Yogurt has become extremely popular due to its healthy attributes including the friendly bacteria, called probiotics, along with other nutrients such as animal protein (about 9 grams per 6-ounce serving), plus calcium, Vitamin B-2 and B-12, potassium, and magnesium.

Why This Matters:

Some customers believe that consuming yogurt or kefir will provide them with the same benefits of a probiotic.  Each of these has different amounts and strains of bacteria, which must be disclosed on the labels.  Store staff and customers are wise to look at product labels to find out what strains are listed.  In the last few years, probiotics have been added to yogurts, but many of these yogurts have been loaded with sugar.

Natural and organic brands usually contain several types of healthy bacteria and use natural sweeteners in some varieties.  Yogurt can be made from cow, sheep, and goat milk as well as non-dairy sources such as soy and coconut.  Regular cow milk yogurt can come in full fat, low fat, or non-fat varieties.   In recent years, Greek yogurt has become even more popular.   Greek yogurt is strained extensively to remove much of the liquid whey, lactose, and natural sugars, giving it a thicker consistency; and for roughly the same amount of calories, can double the protein, while cutting sugar content by half.  With less lactose, Greek yogurt can be less likely to cause stomach upset in lactose-intolerant individuals.

Kefir is also a cultured milk product similar to yogurt but contains more bacteria and yeast (called kefir grains) and often different strains of bacteria cultures including Lactobacilus caucasius (friendly bacteria) plus Saccharomyces kefir and Torula kefir (yeast strains).   Kefir differs from yogurt due to the addition of yeast, but also because it is more liquid than yogurt.  Kefir cultures are also sold so that consumers can make their own kefir.  Kefir can also be made from non-dairy milks such as almond and soy using the same cultures so vegans and lactose-intolerant people can receive the benefits of the friendly bacteria.  Kefir is mostly sold as a cold beverage in low fat, non-fat, whole milk, Greek style, and organic varieties. 

How Cheese is Made

The majority of cheese sold in the United States is made from cow’s milk.  Cows graze primarily on ground cover grasses and when they feed, they often take up some of the soil in their bites. This gives their cheeses an earthy flavor that will vary greatly from one geographic location to another.   Cow’s milk cheese made from grazed animals will have a yellow hue as opposed to corn fed animals which yield cheese with a more pasty white color. The yellow coloring is from carotene found in the pasture grasses.

Cheesemaking starts out similarly to yogurt in that starter cultures of good bacteria are added to clean milk to start the process.  These cultures help determine the flavor and texture of the cheese.  Next, a milk-clotting coagulant is added so the milk can form a custard-like mass.  The liquid whey is separated from the milk solids (curds) and the curds are heated at different temperatures depending on the type of cheese that is being produced.   Different handling techniques and salting affect how the curd is transformed into the many cheese varieties.  Cheese may also be pressed and cured (aged), depending on the variety and style of the cheese.  Aging requires cheese to be moved to a controlled temperature and humidity facility where cheese may be aged for as long as 10 years or more.  It takes approximately 10 pounds of milk to make one pound of cheese.

Cheeses are made from either raw, unpasteurized milk, or pasteurized milk.   All milk to make cheese starts as raw milk.  When making pasteurized cheese, most, if not all, bacteria are destroyed.  Since the bacterium is responsible for many of the flavor and ripening characteristics of cheese, pasteurized cheeses tend to be more subtle and bland in flavor. 

Cheese made from milk which has been only been partially pasteurized is called unpasteurized cheese since the heating process does not meet pasteurization specifications, but is hot enough to kill any harmful bacteria.   Since the process does not kill all the bacteria, these cheeses tend to have more flavor than pasteurized cheese.  Unpasteurized, raw milk cheeses are typically the most flavorful.   Since processing retains the bacteria, all raw milk cheese must be held in a cool, temperature-controlled environment for 60 days and then be inspected prior to sale.  The presence of any harmful bacteria will become evident during the holding period and is typically eliminated because dangerous bacteria cannot survive in such an environment. 

Rennet, the coagulant that is used to produce most commercial cheese, is derived from the stomach tissues of young animals – kid (goat), calf (cow), or lamb (sheep).   Vegetarians and others, who avoid consuming products from animals, prefer the use of non-animal rennet called microbial rennet, vegetable rennet, or citric acid or vinegar.  Microbial rennet is produced by a specific type of mold, fungus, or yeast organism grown and fermented in a lab setting.  Vegetable rennet comes from plants that produce certain enzymes that have coagulating properties.  Both of these types of rennet are used less frequently due to inherent flavors that may be bitter, especially when cheese is aged.  Citric acid or vinegar is typically only used for soft cheeses like Ricotta and also results is a specific flavor profile.

In the 1990s a new microbial rennet was introduced and rapidly adopted for use in the cheese industry.  Called FPC-Fermentation Produced Chymosin Rennet, this rennet is produced by taking the rennin producing gene out of the animal cell’s DNA string and then inserting it into the bacteria, yeast or mold host cell’s DNA string.  This type of rennet is a GMO product, and according to the rennet culture companies, 90% of cheese produced in North America is produced using this FPC rennet.  The result is that most cheese in North America is made from vegetarian friendly but still animal originated, GMO derived FPC rennet.  And while the use of this type of rennet is banned in GMO-free European countries, European cheesemakers use FPC rennet for the American market because it is cheaper and more consistently available.

The FDA does not require that the cheese ingredient label denote the type of rennet.  Cheesemakers can simply label the rennet as “enzymes.”  Some cheese manufacturers and large natural food retailers can label their cheese with “vegetarian rennet” which helps vegetarian customers know which cheese fits their values and lifestyle.

Why This Matters:

Vegetarians have a particular interest in the manner in which cheese is made and look for vegetarian options.  Ingredient labels can be misleading about which kind of rennet has been used, sometimes simply listing the word rennet or the word enzymes.  Vegetarians should specifically look for the words vegetable rennet in the list of cheese ingredients.

Goat & Sheep Cheese

Cheese made from goat and sheep has a distinctive flavor that differs from cow’s milk cheese due to the food these animals consume.   Goats seek the highest and most tender leaves when they graze, stripping bark from trees and going after the tallest, sweetest grasses.  Goat milk produces cheeses with a more acidic and bright goat flavor, which is sometimes described as barn-yard-like. It also has the least amount of fat in it.   Sheep, on the other hand, will primarily only eat the tender, sweet top blade grass.  If a grazing herd of sheep is left on pasture for an extended period of time, the field will look as if it’s been mowed by a grounds crew.  Sheep milk cheese is the highest in fat which, when added to their grazing preferences, gives sheep milk cheeses a rich, buttery, and usually less assertive flavor. 

Goat cheese is lower in fat, calories, sodium, and cholesterol than cow’s milk cheese.  It also provides more calcium.  Some people find it easier to digest than cow’s milk cheese because the butterfat molecules are shorter, making them more digestible.

Sheep have been raised for their milk for thousands of years and were milked before cows. The world's commercial dairy sheep industry is concentrated in Europe and the countries on or near the Mediterranean Sea.  Sheep milk is highly nutritious, richer in vitamins A, B, and E, calcium, phosphorus, potassium, and magnesium than cow's milk. It contains a higher proportion of short- and medium-chain fatty acids, which are recognized for their health benefits.  For example, short-chain fatty acids have little effect on cholesterol levels in people and they make the milk easier to digest.  Some of the most famous cheeses are made from sheep milk:  Feta (Greece, Italy, and France), Ricotta and Pecorino Romano (Italy), and Roquefort (France).


Words to Remember


Kefir is a drinkable, cultured dairy product similar to yogurt, but with specific differences in the bacteria, the flavor, the consistency (kefir is more liquid), and the manner in which the culture is activated.



An enzyme found in the stomach of young milk-fed calf, lamb, or goat that is used to make cheese. The enzymes cause milk to separate into the solid curds and the liquid whey.