Delivering Enzymes in Functional Foods

by Heather Granato

"It's not just what you eat--it's what you absorb."This phrase has taken on new meaning in today's fast-paced world. Eating out,rich foods, nutrient-depleted soil, an overabundance of refined carbohydrates,and few fruits and vegetables--is it any wonder that America is a nation ofoverweight, undernourished people?

While consumers search for the magic diet that could maximizetheir health potential, one of the keys is waiting on the shelves and within thewhole foods they overlook. Enzymes are large proteins that work like keys tounlock a specific door. They catalyze chemical reactions, or increase theirrate, without being affected themselves and are responsible for breaking downsubstances into their basic structures.

More than 3,000 types of enzymes have been identified. They canbe classified into six main groups: hydrolases, isomerases, ligases, lyases,oxidoreductases and transferases. The primary enzymes of concern in thenutritional and functional food industries are the hydrolases. They work byadding a water molecule to the substance to be impacted. The main classes ofhydrolytic enzymes are protease (proteins), amylase (carbohydrates), lipase(fats or lipids) and cellulase (cellulose). Enzymes only work on a specificsubstrate--an enzyme that affects fat will not work to help digest protein, forexample. Within the classes, individual enzymes are also highly specific in thesubstrate they affect. Lactase acts on the milk sugar lactose, while papainbreaks proteins into amino acid components.

Enzymes can improve the digestion of food, reduce stress in thegastrointestinal (GI) tract, help maintain normal pH levels and promote thegrowth of healthy intestinal flora. Many foods contain the enzymes necessary fortheir digestion. However, enzymes are highly susceptible to changingenvironmental conditions such as pH, moisture and temperature, and are destroyedby the high temperatures used in cooking and processing.

Enzymes can be sourced from animal tissue, plants ormicroorganisms such as fungi or bacteria. Pancreatin is the best-known animalsource enzyme; it is a proteolytic enzyme that acts in a narrow pH range. Plantenzymes include papain (from papaya) and bromelain (from pineapple); they aregenerally effective in a broader pH range and are also usually proteolytic.Fungal or bacterial enzymes offer the widest action and the broadest range ofactivity in the body.

To produce commercial quantities of enzymes, many manufacturersisolate microbial strains that produce the desired enzyme or geneticallyengineer the strain to produce a desired enzyme. Through fermentation carriedout under optimal conditions, manufacturers can produce sufficient quantities ofproduct. Production is governed by federal agencies (i.e., the Food and DrugAdministration) and state regulations. Many manufacturers also follow industryguidelines for production. Enzymes are available in a variety of physical forms:liquids, slurries, granules and powders.

Foods & Functional Foods

Since men first found that enzymes could make beer from grain,enzymes have played an important role in food production. Enzymes are used inmany commercial processes to speed up catalytic reactions, and are thendeactivated through heat or other environmental change. Consider rennet, anenzyme mixture from the stomach of calves, used in cheese production tofacilitate the separation of curd from whey. Today, a purified form of the majorenzyme--chymosin--is produced microbially from genetically modified organisms (GMOs).This allows cheese producers to have a plentiful source at a reasonable cost;also, vegetarians and those following kosher guidelines can now consume cheesethat contains no meat product.

Cheese and other dairy products have also given enzyme producersan educational opportunity. It is estimated that 50 million Americans arelactose-intolerant, with up to 80 percent of blacks and 90 percent of Asiansaffected. These consumers lack the enzyme lactase, which converts the milk sugarlactose into two digestible sugars--glucose and galactose. Without adequatelactase, lactose ferments in the intestine, producing gas and other sideeffects. With McNeil Nutritionals' introduction of Lactaid, a milk containinglactase, consumers found a way to enjoy a dairy product and gained anunderstanding of how enzymes help with digestion.

McNeil also offers Lactaid as a dietary supplement. As consumershave become more aware of nutrient absorption, enzyme supplements have becomeincreasingly popular. "Enzymes are widely used as in vivo digestiveaids," said Phil Ronsivalli, spokesman for Kennesaw, Ga.-based DeerlandEnzymes. "There is even growing discussion about the possible beneficialuse of enzymes to replace some drugs or analgesics."

However, as with many other categories of dietary supplements,there is a growing interest in providing nutrients through functional andfortified foods, rather than simply in a pill. "Enzymes can help digestfunctional foods and make the ingredients more bioavailable," said RohitMedhekar, Ph.D., technical resources manager with Forsyth, Mo.-based NationalEnzyme Co. "Any food products that need to be digested before the nutrientscan be absorbed by the body are good candidates for added enzymes."

One example is the nutritional bar market. There are now bars tomeet every type of dietary requirement--high protein, low carb, diabetic, men's,women's, etc. Consumers are looking to get full nutrition, even mealreplacement, from a small amount of food packed with nutrients. "Addingenzymes to functional food products that are high in protein, for example, canhelp consumers better utilize those nutrients," said Gabrielle Sill,marketing manager with Specialty Enzymes Co., based in Chino, Calif.

Functional foods are also targeting the aging baby boomers. Asthe body ages, natural enzyme production slows, making it more difficult tofully absorb nutrients through food and equally important to ingest appropriateenzymes with foods. Boomers turning to nutritional beverage powders for an easymeal could find enhanced nutrient absorption if the powder contained enzymes."Dry beverages that you rehydrate are a good way of deliveringenzymes," said Peter Moodie, sales director for New York-based EnzymeDevelopment Corp. "However, the heat processing poses concerns, and therecan be an issue with the expense of delivering enzymes through that channelrather than just as a supplement."

The beverage field epitomizes some of the inherent difficultieswith adding enzymes to functional foods and beverages. As mentioned previously,there are three major factors that affect enzymes' efficacy andfunctionality--temperature, pH and moisture. "One has to be careful whenadding enzymes to beverages since they will start processing their substrate assoon as they come in contact with water," Medhekar said. "This canalter the taste and aesthetic nature of the beverage." On Lactaid's Website, the company notes that the milk is sweeter than regular milk because theprotein has been broken into simple sugars. Ready-to-drink beverages face theproblem that added enzymes would quickly break down the appropriate nutrients,changing the taste profile. Also, the enzymes would not be in a form deliverableto the intestines to help further absorb nutrients in the product.

Also, as Moodie pointed out, there are concerns with the heatinvolved in most food production. "Most enzymes are used in processing andare inactive when the food is delivered because they have been heated to a pointwhere the enzyme protein is denatured and is no longer active," he said.

As manufacturers explore the possibilities available for addingenzymes for nutrient absorption and health benefits, suppliers caution to keepan eye on safety. "Safe handling of the enzyme preparation is a huge issuein the enzyme market," Moodie said. "Enzymes represent a potentialrespiratory risk."

Despite the many beneficial properties they confer,enzymes--like all proteins--have the potential to become an allergen if peoplebecome sensitized. Safe handling of enzyme preparations can be accomplishedthrough proper work practices, engineering controls and use of protectiveequipment. When working with enzymes, it is important that the productionprocess does not generate aerosols or come in direct skin contact.

The Enzyme Technical Association (www.enzymetechnicalassoc.org)offers brochures about safely working with enzymes and other industry concerns.Also, manufacturers that are new to the enzyme field could benefit from workingwith an experienced contract packer that can assist with production. Manysuppliers offer contract-packing services and are familiar with the safety andprocessing aspects inherent to functional food and dietary supplementproduction.

For manufacturers purchasing enzymes for use in functional foodproducts, suppliers suggest taking several steps to ensure the enzymes meet therequirements. The Committee on Food Chemicals Codex (FCC) publishes a referencemanual including monographs and testing methods for enzymes; the U.S.Pharmacopeia (USP) also publishes standard assays directed more towardpharmaceutical use and animal-derived enzymes. Assays are used to detect enzymeactivity, and the assays are specific to the type of enzyme and the source.

Rather than purchasing by weight, enzymes are sold on the basisof potency. Assays evaluate the quantity of hydrolysis that occurs underspecific conditions. This includes a range of concentrations, quantities, pH's,temperatures and substrates. Just because a buyer receives 50 mg of papain, hecannot know whether the activity is 1 FCC unit/mg or 50,000 FCC unit/mg.

As consumers become more familiar with the benefits of enzymes,they will start to look for them on the labels of both dietary supplements andfunctional food products. What manufacturers and suppliers must collaborate onis whether the long-term benefits of functional food products with enzymes willpay off in the nutritional market. "If properly produced, handled andemployed, enzymes definitely bring something to the party," Ronsivallisaid. "The trick is to know where, when, how and under what conditions touse enzymes for the desired effect."

Editor's Note: Some information sourced from the EnzymeTechnical Association (www.enzymetechnicalassoc.org).