Probiotics have been with us for a long time.
Think of fermented cabbage dishes, sour milk products and pickled vegetables. These traditional methods of food preservation extended shelf life by reducing pH or improved taste by producing flavorful bacterial byproducts. They also ensured a high count of probiotics. Today we have to look a bit harder because many modern food industry methods kill helpful bacteria. Food manufacturers have discovered their value however and each week more probiotic products are being introduced across the globe.
Today in Japan, one will find dozens of probiotic-containing products on supermarket shelves, ranging from fortified drinks to candy containing strains from the lactobacillus and bifidobacterium genera.
In Europe, the dairy sector is the most developed segment of the market. Probiotic yogurts and fermented milks that are sold in a convenient “daily dose” format are the most widely used. Consumer acceptance of probiotic-containing products varies greatly across Europe. Northern European and Scandinavian countries, which have a long traditional consumption of fermented dairy products, demonstrate the highest acceptance in the European probiotic market. Within Europe, the use of probiotic dietary supplements has been slow to gain acceptance, but it is fast becoming a booming category.
In the United States, the situation is reversed, with dietary supplements by far being the most accepted product format (vs. probiotic-containing foods such as yogurt and fermented milk). It is generally established that US consumers are far more willing than their European counterparts to take supplements, which may explain the large difference. Conversely, the functional dairy food market in the US for probiotic-containing products is still quite under developed. However, this situation is changing rapidly as major probiotic manufacturers are teaming up with large dairy and food companies to produce more probiotic containing functional foods such as smoothies, yogurts, bars, cereal, candy, and other fortified food and beverage items.
Most new probiotic products have one or more types of bacteria, although some may contain yeasts. Lactic acid bacteria (LAB) including Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus casei Shirota, Lactobacillus gasseri, as well as Bifidobacterium bifidum are the most common probiotic bacteria added because they are already found in many fermented foods and have low level of infection associated with them. Therefore, most LAB are generally recognized as safe.
Hundreds of new probiotic food and beverages have been introduced in the last decade. Some of the labels can be confusing for consumers. How many billions are enough to have a good effect, for example? And which bacteria are best? Is a prebiotic or fiber needed? The World Health Organization says that “probiotics…should not only be capable of surviving passage through the digestive tract, by exhibiting bile and acid tolerance, but also should have the capability to proliferate in the gut.” As many as 1000 and possibly many more strains of helpful bacteria reside inside each one of us. Fewer than a hundred have names while the very few such as those in yogurt are grabbing the spotlight. All of this means that consumers must be patient and the facts will eventually emerge. Meanwhile, the best advice is to include some probiotic-rich foods in your diet daily.
Yogurt is the most popular probiotic-rich food around the globe. In the United States, yogurt is usually enjoyed sweet while in the Middle East and India, plain yogurt is used to cool down curries and spicy stews. Lactobacillus acidophilus or Lactobacillus bulgaricus are the required fermenting bacteria in the United States. The milk used to make yogurt can come from any animal such as a goat, sheep or cow. In many countries, the milk is pasteurized first and then the bacteria cultures are added. Bacteria digest the lactose or milk sugar and other carbohydrates which produces lactic acid. The lactic acid gives yogurt its tart taste and thick texture while making an inhospitable place for bad bacteria to thrive.
The National Yogurt Association (NYA) in the United States has introduced a “Live & Active Cultures” seal. To carry this, a yogurt must contain at least 100 million cultures per gram or 20 billion per 8 ounce serving. But remember, just because they are live doesn’t mean they are active. Transport and shelf conditions will determine how many live cultures make it into your stomach. The seal is voluntary and some yogurts don’t use the seal though they may qualify. The important thing to know is whether the milk was pasteurized before or after the fermentation process. If the bacteria were added before pasteurization, the heat may wipe out the live cultures. Adding to the confusion is that strains of bacteria are sometimes called different things in different countries. No one agency regulates the naming of bacteria, which is why the name Bifidobacterium regularis exists.
When choosing yogurt, here are a few things to consider:
• Look for the NYA seal.
• Reach for plain yogurt to which you can add fresh fruit or granola. Sweetened yogurt can have as much sugar as a candy bar.
• Lean towards lower fat products. Regular is made with whole milk (3.5% fat).
• Inspect the label for added fiber. These are prebiotics which feed the probiotic bacteria. These come in at least four varieties:
o Pectin, a type of fiber found in apples.
o Inulin, fiber found in many fruits and vegetables.
o FOS (fructo-oligosaccharide)
o Polydextrose, a fiber made from dextrose and sorbitol
Other Food Sources of Probiotics
• Frozen yogurt: National Yogurt Association states that frozen yogurt must contain at least 10 million cultures per gram at the time of manufacture.
• Kefir is a fermented beverage which can be made from many sources: cow, goat or sheep milk as well as from plants including soy, rice and coconut. Lactobacillus kefiri and species of Leuconostoc, Lactococcus or others are injected into these milks. After the milk ferments and thickens, the grains, which clump like cauliflower, are strained out. Kefir comes in whole or low-fat varieties, plain or flavored, organic or traditional. Kefir is believed to have originated in the Caucasus mountains in Russia and Turkey.
• Buttermilk is a by- product of butter production.
• Acidophilus milk is the result of fermenting milk with lactobacillus acidophilus.
• Lebne, popular in the Middle East, is a spreadable cheese made from yogurt.
• Viili, popular in Finland, is a cultured whole milk; kermavilli is a cream that has been cultured.
•Lassi, dadhi, maziwa lal, chach are fermented products enjoyed widely in India.
•Aged cheeses including Cheddar, Swiss, Parmesan, Gouda and many others start with lactic acid bacteria. Lactic acid spurs the formation of curds and whey. The curds ferment for days, weeks and sometimes years. Chemicals are formed by the bacteria as the cheese ages, giving it appealing flavor.
•Most countries embrace some form of fermented cabbage: Sauerkraut in Germany, kimchi in Asia, curtido in Central America or choucroute in France. Salt is all that is required to get the process of fermentation going. The most common probiotic found is Lactobacillus plantarum. However, processing destroys the healthful bacteria; if they remained, the jars or cans would burst from the growth of the live bacteria. Also some preservatives including sodium benzoate will kill bacteria. Try to buy fresh or check labels to determine if probiotics have been added afterward.
•Pickles and olives may be rich in probiotics if they are produced from traditional methods such as brine-curing and salt-curing. Many unfortunately are pasteurized and preserved with sodium benzoate to prolong shelf-life.
Other sources, some new, include energy bars, probiotic drinks, pizzas, chewing gum, microbrew beers, cottage cheese, miso, pickled ginger, tempeh and some baby formula.
A prebiotic is an indigestible carbohydrate that feeds or stimulates the growth of probiotics. A popular prebiotic is the fiber inulin. Inulin is a soluble fiber with bonds strong enough to withstand digestive attempts by our guts. Inulin is ample in bananas, garlic, and onion, as well as asparagus, artichoke, wheat and chicory root.
Supplements are an alternative to getting probiotics in food.
Probiotic supplements come in capsules, tablets, powders, wafers and liquids. The correct dosage of probiotics remains a matter for research. Experts are trying to come up with some guidelines.
According to Gary Huffnagle in his outstanding book The Probiotics Revolution “the more ambitious the goal, the higher the suggested daily dose.”
Which strains of probiotics?
Take a broad number if you are taking them to maintain general good health. Use specific kinds if you are targeting a certain condition or disease. Remember there are only a small number of probiotics actually studied and even named so there will be new ones coming out which may be better for your problem.
Check Labels on Probiotic Supplements
• Look for the genus, species and strain. For example, Lactobacillus casei Shirota shows the genus, species and strain in that order.
• Check for microbe counts, not weight.
• Look at the expiration date, very important for probiotics.
• Added prebiotics such as inulin can be a bonus.
• Type of delivery such as enteric coating may protect your purchase from harsh stomach acids.
How to Take Probiotic Supplements
• With or without food? Experts disagree.
Huffnagle advises opening the capsule and adding to milk or juice, or sprinkling on a food such as cereal or yogurt. The probiotic is then evenly distributed and benefits all areas of the body, such as the mouth and throat. Other sources advise taking a supplements in between meals when stomach acid is lowest.
• The best bet may be those foods containing calcium: yogurt, milk or cheese. Calcium helps the bacteria adhere to the intestinal wall, Calcium carbonate or an antacid is counterproductive however, as the lowering of acid also allows a stickier environment for pathogens.
• Take them twice a day for better colonization.
• Store in the refrigerator in air-tight glass containers.
• Don’t leave them home, when travelling. It is acceptable to keep them at room temperature for a few days or a week. Better yet, stow them in the mini-bar or fridge.
Probiotic Supplement Precautions
If you are planning on using a probiotic product, consult your health care provider first. No probiotic therapy should be used in place of conventional medical care or to delay seeking that care.
• Effects from one species or strain of probiotics do not necessarily hold true for others, or even for different preparations of the same species or strain.
• If you use a probiotic product and experience an effect that concerns you, contact your health care provider.
Have we reached a stage where we can recommend probiotics? Absolutely. Have we reached a stage where we can pinpoint which strain and how much? Hardly.
Knowledge of probiotic species, specific strains, dosages, safety, and shelf life is not adequately summarized to put forth consistent recommendations. Prebiotic fibers also remain in need of much more research as far as sources, fermentation, and dosages required for health effects.