Got Mi l k?Make Sure It'sP a s t e u r i z e dBy Linda Bren

Ppasteurization, since its adoption'in the early 1900s, has beencred i t ed w i t h d rama t i ca l l yreducing illness and death caused bycontaminated milk. But today,some people are pass

ing up pasteurized milkfor what they claim istas t ie r and hea l th ie r

" r a w m i l k . "

Public health offi

c ia ls cou ldn ' t d is

a g r e e m o r e .

Drinking raw (untreated) milk or eatingraw milk products is"like playing Russian roulette with your health,"says John Sheehan, director of the Food andDrug Administration's Division of Dairy and Egg Safety."We see a number of cases of foodborne illness every yearrelated to the consumption of raw milk."

J a c k L e f k o w i t z

FDA Consumer / September-October 2004 / 29

More than 300 people in the United killing disease-causing bacteria, pas- is barely perceptible.States got sick from drinking raw milk teurization destroys bacteria that cause "Milk is a good source of the vita-or eating cheese made from raw milk in spoilage, extending the shelf life of mins thiamine, folate, B-12, and ribo-2 0 0 1 , a n d n e a r l y 2 0 0 b e c a m e i l l f r o m m i l k . fl a v i n , " a d d s S h e e h a n , " a n d p a s t e u r i z a -these products in 2002, according to Milk can become contaminated on tion results in losses of anywhere fromthe Centers for Disease Control and the farm when animals shed bacteria zero to 10 percent for each of these.Prevention. into the milk. Cows, goats, and sheep which most would consider only a mar-

Raw milk may harbor a host of dis- carry bacteria in their intestines that ginal reduction."ease-causing organisms (pathogens), do not make them sick but can cause While the major nutrients are leftsuch as the bacteria Campylobacter, illness in people who consume their unchanged by pasteurization, vitaminescherichia, listeria, salmonella, yer- untreated milk or milk products. D, which enhances the body's absorp-sinia, and brucella. Common symp- But pathogens that are shed from tion of calcium, is added to processedtoms of foodborne illness from many animals aren't the only means of con- milk. Vitamin D is not found in signifi-

Research has shown that there is no

significant difference in the nutritional valueof pasteurized and unpasteurized milk.

of these types of bacteria include diarrhea, stomach cramps, fever, headache,vomiting, and exhaustion.

Most healthy people recover fromfoodborne illness within a short periodof time, but others may have symptomsthat are chronic, severe, or life-threatening.

People with weakened immune systems, such as elderly people, children,and those with certain diseases orconditions, are most at risk for severeinfections from pathogens that maybe present in raw milk. In pregnantwomen. Listeria monocytogenes-causedillness can result in miscarriage, fetaldeath, or illness or death of a newborninfant. And Escherichia coli infectionhas been linked to hemolytic uremicsyndrome, a condition that can causekidney failure and death.

Some of the diseases that pasteurization can prevent are tuberculosis, diphtheria, polio, salmonellosis,strep throat, scarlet fever, and typhoidf e v e r.

Pasteurization and ContaminationThe pasteurization process uses heat

to destroy harmful bacteria withoutsignificantly changing milk's nutritional value or flavor. In addition to

tamination, says Tom Szalkucki, assistant director of the Wisconsin Centerfor Dairy Research at the University ofWisconsin-Madison. Cows can pickup pathogens from the environmentjust by lying down—giving germs theopportunity to collect on the udder,the organ from which milk is secreted."Think about how many times a cowlays down in a field or the barn,"says Szalkucki. "Even if the barn iscleaned thoroughly and regularly, it'snot steamed. Contamination can takeplace because it's not a sterile environm e n t . "

The Health HypeRaw milk advocates claim that

unprocessed milk is healthier becausepasteurization destroys nutrients andthe enzymes necessary to absorb calcium. It also kills beneficial bacteriaand is associated with allergies, arthritis, and other diseases, they say.

This is simply not the case, says Sheehan. Research has shown that there isno significant difference in the nutritional value of pasteurized and unpasteurized milk, he says. The caseins,the major family of milk proteins, arelargely unaffected, and any modification in whey protein that might occur

cant levels in raw milk."Pasteurization will destroy some

enzymes," says Barbara Ingham, Ph.D.,associate professor and extension foodscientist at the University of Wisconsin-Madison. "But the enzymes thatare naturally present in milk are bovineenzymes. Our bodies don't use animalenzymes to help metabolize calciumand other nutrients."

"Enzymes in the food that we eat anddrink are broken down in the humangastrointestinal tract," adds Ingham."Human bodies rely on our own nativeenzymes to digest and metabolizef o o d . "

"Most of the native enzymes ofmilk survive pasteurization largelyintact," says Sheehan, "including thosethought to have natural antimicrobialproperties and those that contributeto prolonging milk's shelf life." Otherenzymes that survive are thought toplay a role in cheese ripening.

Ingham says that pasteurization willdestroy some bacteria that may be helpful in the fermentation of milk intoproducts such as cheese and yogurt,but the benefit of destroying the

harmful bacteria vastly outweighs thesupposed benefits of retaining thosehelpful microorganisms. Plus, by add-

30 / September-October 2004 / FDA Consume

A Sampling of Raw Milk Incidents• July 2004—^The Indiana Public Health Department advised consumers to check their refrigerators and freezers for raw milk cheese that maybe contaminated with salmonella. Routine product sampling foundthe bacteria in lot number 139 of "Natural Raw Milk Cheese" made byMeadow Valley Farm after the cheese was distributed to farmers' markets and specialty food stores in parts of Indiana and Wisconsin.• 2002-2003—Two children were hospitalized in Ohio for infectionwith Salmonella enterica serotype Typhimurium. These children and 60other people in Illinois, Indiana, Ohio, and Tennessee developed bloodydiarrhea, cramps, fever, chills, and vomiting from S. Typhimuriumtracked to consuming raw milk. The milk producer voluntarily relinquished its license for selling raw milk upon recommendation of theOhio Department of Agriculture.• 2000-2001—In North Carolina, 12 adults were infected with Listeria monocYtogenes linked to homemade, Mexican-style fresh soft cheeseproduced from contaminated raw milk sold by a local dairy farm. Tenof the 12 victims were pregnant women, and infection with the bacterium resulted in five stillbirths, three premature deliveries, and twoi n f e c t e d n e w b o r n s .• 1998—In Massachusetts, 66 people received injections to protectagainst potential exposure to rabies after drinking unpasteurized milkfrom a local dairy. A cow that died at the dairy was found to be infectedwith rabies. Transmission of the rabies virus through unpasteurizedmilk, although not the common route of infection, is theoretically possible, according to the Centers for Disease Control and Prevention. ■Sources: CDC, Indiana State Board of Animal Health

ing the microorganisms that we needfor fermentation, we can assure a consistently high quality product."

Sc ience has no t shown a connec t i onbetween drinking raw milk and disease prevention. "The small quantitieso f an t i bod ies i n m i l k a re no t abso rbedin the human intestinal tract," saysIngham. "And there is no scientifice v i d e n c e t h a t r a w m i l k c o n t a i n s a n

an t i - a r t h r i t i s f ac to r o r t ha t i t enhancesres is tance to o ther d iseases . "

Fans of raw milk often cite its creamyrich taste, says Szalkucki, who addsthat it may be creamier because it isnot made according to the standardsfor processed milk. "If you go to a grocery store and buy fluid milk, it's beenstandardized for a certain percentageof fat, such as 2 percent," he says. "Rawmilk is potentially creamier because ith a s n o t b e e n s t a n d a r d i z e d a n d i t h a sa higher fat content."

T h e L a wIt is a violation of federal law enforced

by the FDA to sell raw milk packagedfor consumer use across state l ines

(interstate commerce). But each stateregulates the sale of raw milk withinthe state (intrastate), and some statesallow it to be sold. This means that insome states dairy operations may sellit to local retail food stores, or to consumers directly from the farm or atagricultural fairs or other communityevents, depending on the state law.

In states that prohibit intrastate salesof raw milk, some people have tried tocircumvent the law by "cow sharing,"or "cow leasing." They pay a fee to afarmer to lease or purchase part of acow in exchange for raw milk, claiming that they are not actually buyingthe milk since they are part-owners ofthe cow. Wisconsin banned cow-leasing programs after 75 people becameinfected with Campylobacter jejuni bacteria in 2001 from drinking unpasteurized milk obtained through sucha p r o g r a m .

R a w M i l k C h e e s e sThe FDA a l l ows the manu fac tu re

and interstate sale of raw milk cheesesthat are aged for at least 60 days at atemperature not less than 35 degreesFahrenheit. "However, recent research

calls into question the effectiveness of60-day aging as a means of pathogenreduction," says Sheehan.

The FDA's Center for Food Safetyand Applied Nutrition (CFSAN) is currently examining the safety of raw milkcheeses and plans to develop a riskprofile for these cheeses. This information will help FDA risk managers makefuture decisions regarding the regulation of these products to protect publich e a l t h .

Ensuring Milk SafetyThe FDA provides oversight for the

processing of raw milk into pasteurizedmilk, cottage cheese, yogurt, and sourcream under the National Conferenceon Interstate Milk Shipments "GradeA" milk program. This cooperativeprogram between the FDA and the 50states and Puerto Rico helps to ensurethe uniformity of milk regulations andthe safety of milk and milk products.The program is based on standardsdescr ibed in the FDA's Pasteur izedMilk Ordinance (PMO), a model code

of regulations that can be adopted bythe states in their own regulations.

Under the Grade A program, statepersonnel conduct inspections andassign ratings and FDA regional milkspecialists audit these ratings, saysRichard Eubanks, M.P.H., a senior milks a n i t a t i o n o f fi c e r o n C F S A N ' s M i l kSafety Team. "It's a rigorous process ofinspection and auditing," he says, and"it covers from cow to carton," startingwith the dairy farm and continuingthrough the processing and packagingof products at milk plants. Productsthat pass inspection may be labeled"Grade A."

The FDA Grade A milk programincludes pasteurized milk from cows,goats, sheep, and horses. Raw milk andraw mi lk cheeses cannot be labeledGrade A, since they are not pasteurizedand not covered under the program. ■

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