FOOD FACTS FOR YOU!

June 2004 Newsletter

Vegetable Nitrates: Are They Harmful to Health?
How Now Mad Cow?
Chronic Wasting Disease and Potential Transmission to Humans
Dr. Seuss was Right: Green Eggs and Ham are OK!
Update on Food Preservation Trainings
Safe Preparation of Infant Formula
What's on Your Mind? (microwave recipes, perfectly ripe fruit, produce decoded, summertime food safety, ultra bleach)

Vegetable Nitrates: Are They Harmful to Health?

The American Academy of Pediatrics in their Complete & Authoritative Guide for Caring for your Baby and Young Child states that mothers should not home-prepare beets, turnips, carrots, collard greens or spinach for very young children. I would like to look at this recommendation and what it means for those feeding young children in Wisconsin .

What is the reason for this recommendation? In some parts of the country, beets, turnips, carrots, collard greens and spinach contain large amounts of nitrates, a chemical that can cause an unusual type of anemia (low blood count) in young infants, referred to as methemoglobinemia or ‘blue baby syndrome.' Baby-food companies are aware of this problem and screen the produce they buy for nitrates; they also avoid buying these vegetables in parts of the country where high levels of nitrates have been detected. Since a caregiver cannot test for nitrates in their food, the American Academy of Pediatrics (AAP) recommends using commercially prepared forms of these foods, especially for infants. AAP further recommends that if a caregiver does choose to prepare these vegetables at home, they should be served fresh and not stored since this may actually increase nitrate levels.

Is methemoglobinemia a problem in Wisconsin ? An article in 2001 in the Wisconsin Medical Journal outlined eight cases of methemoglobinemia in Wisconsin during the period 1990 through 1998. The condition involves the oxidation of red cell hemoglobin to a state that it is unable to transport oxygen. Due to lack of oxygen, affected infants appear cyanotic and may turn blue, hence the name of the article: Eight Blue Babies. A review of the hospital records for these eight cases found that 3 of these cases involved infants whose formula was prepared with water from nitrate-contaminated wells. Risk factors identified in the other cases included use of folk remedies, misuse of over-the-counter analgesics and an inherited enzyme deficiency. Several recent groundwater quality surveys have identified nitrate contamination as one of the most common water supply problems in the Midwestern United States. In Wisconsin , the problem is most severe in the southern half of the state, which is heavily agricultural and where 6-7% of wells may be contaminated. Groundwater nitrate levels follow seasonal patterns with the highest levels occurring in late spring and early summer (April through June), shortly after the planting season when fertilizers are applied (Wisconsin Medical Journal, 2001. vol.100, p. 43-47.)

If well water is the main contributing factor, at least in Wisconsin , then how did the issue become tied to homegrown vegetables? Extensive reviews have failed to identify any infants with methemoglobinemia caused by consuming plant nitrate. Nitrate poisoning appears to be associated only with ingestion of nitrate in water rather than naturally occurring nitrate in foods. Under some conditions, plant nitrates may be converted to nitrite before feeding. There are two documented instances in Germany in the 1960's where infants were fed spinach containing high levels of nitrite. The spinach involved in these instances was pureed in the home and stored under questionable conditions; apparently becoming toxic during storage because of conversion of nitrate to nitrite. (AAP Policy Statement: http://aappolicy.aappublications.org/cgi/reprint/pediatrics;46/3/475.pdf )

So what recommendations can be made for caregivers wanting to prepare home-grown vegetables for infants? Caregivers often prefer to prepare food for their children at home, especially if there is an abundance of home-grown produce. But if vegetables such as beets and spinach are grown under low light conditions or fertilized with high nitrogen fertilizer (lawn fertilizer, for example) they can accumulate a lot of nitrate. Beets and spinach are the primary culprits and act as nitrogen sinks to accumulate high levels of nitrates if they are available. The nitrates are then converted to nitrites in storage. When infants and young children consume these nitrites they are susceptible to methemoglobinemia (blue baby syndrome). Nutrient sources such as compost or slow-release fertilizer are, therefore, recommended for home gardens. So, caregivers can grow their own vegetables and process them into baby food at home, but they must take special care to choose crops that were properly grown and they should not store any processed spinach or pureed carrots for long periods before feeding them to children or infants.

My thanks to Faye Malek (Manitowoc County) who first brought this issue to my attention, and to Karen Delahaut (Vegetable Crops Specialist) for her expertise in preparing a response!

It's been almost half a year since the first case of bovine spongiform encephalopathy (BSE), or Mad Cow Disease, was identified in an animal in the United States in December of 2003, and during that time public interest in the issue has declined. The May 2004 issue of Tufts University Health & Nutrition Letter revisits the issue of food safety associated with this topic. Following is a summary of that article.

While it's often said that the US food supply is the safest in the world, Japan , the largest importer of US beef, will not allow any of our beef products on its shores. Nor will Argentina , Denmark , New Zealand and about 30 other countries. Should these countries be worried? Are the changes that have been made since the discovery of BSE in a dairy cow in Washington State enough to ensure the safety of beef consumed in, or exported from, the US ?

Regulatory change. Measures to keep Mad Cow disease out of the US beef supply have been in place since the 1980s. In 1989 the US banned the importation of live cattle and most bovine parts from Britain , which was then struggling with an outbreak of the disease. In 1997 the US went a step further by banning the practice of feeding cattle the ground-up remnants of other ruminants (cattle, sheep and goats) – a practice associated with the appearance of the disease in Britain. The infected cow found in Washington State in December was between 6 and 7 years old, just old enough to have been fed ruminant material before the ban went into place in 1997. More recently, the US Department of Agriculture has made some changes regarding which cattle can be turned into human food. Cattle known as ‘downer' cows, meaning they cannot walk to slaughter on their own, are now banned from the food supply. Even a cow with a broken leg that doesn't have an obvious case of Mad Cow Disease cannot be turned into human food. Also banned is mechanically separated meat obtained when processors crush up bones that contain scraps of meat on them, then filter out the bone through a sieve and put the remaining meat into food products. The problem was that spinal tissue and potentially infected bone marrow could end up in food. In addition, the USDA now says that cattle over 30 months of age, those most likely to be infected with BSE, cannot be a source of ‘specified risk materials' for food- brains, spinal cords, and nervous system components. The USDA has also increased testing for the disease, from 20,000 animals per year to roughly 200,000 in a one-time effort to determine if the disease is present in the US .

But loopholes remain. The changes that have been made, both recently and within the past years, do not close all the loopholes that would allow BSE into our food. For instance,

• While brain and other nervous tissue will no longer be allowed to be taken from cattle over 30 months of age, animals as young as 20 months of age have tested positive for the disease.

• While mechanically separated meat is banned, a system known as automatic meat recovery (AMR) is still in place. AMR uses machinery that strip every bit of meat off carcasses, including off of bone and spine. The meat from this process is used in products like sausage and hotdogs and has been shown to sometimes contain nervous system tissue.

• The ban on downer cows may not be complete, since legislation has been introduced to allow some downer cows to remain in the human food chain.

• The ruminant feeding ban may not be complete enough: young cows are allowed to be fed cows' blood for nourishment, and the practice of feeding cattle the remnants of other animals such as pigs and chickens, which may be carriers of the disease, still exists. In Europe , no protein from any mammal is allowed to be fed to any animal that becomes food for humans.

• The one-time increased testing to 200,000 animals still represents testing of a small fraction (less than 1%) of the 35 million cattle that are slaughtered in the US every year. So many animals slaughtered simply are not tested.

Risk analysis. Fortunately, the disease risk to humans is not as great as initially thought. More than 179,000 cases of BSE were documented in Britain , peaking in 1992 when between 35,000 and 40,000 sick cattle were identified. Very few cases were identified in 2003. Cases of variant Creutzfeldt-Jakob disease (vCJD), the human disease linked to BSE, peaked in Britain in 2000, with 28 people infected. There have been 150 cases of the illness in humans in the United Kingdom altogether, and only one case in the US , in a woman born and raised in Britain . Based on the experience in Britain and elsewhere, the risk to human health in the US from this particular disease appears low. Risk to human health from the consumption of beef is much greater when bacterial illnesses such as E. coli 0157:H7 or Salmonella are considered.

What you can do. According to Tufts University , there are several things that you can do if you are very concerned:

• Avoid eating cow brains, as well as hotdogs, sausages, and ground meat. ( Ground meat from a particular cut of meat, i.e. ground round or ground chuck represent little to no apparent risk.)

• Buy muscle-only cuts of meat, i.e. boneless, not cuts with bones such as T-bone steaks.

• Buying certified organic or certified 100% grass-fed beef may decrease, or eliminate, your risk.

And overall, realize that the risk to human health is extremely minimal to start. Any changes that you choose to make will further decrease the risk that you may be exposed to. Tufts University Health & Nutrition Letter May 2004. www.healthfinder.tufts.edu

Chronic Wasting Diesease and Potential Transmission to Humans

(Note: This information is summarized from an article in the June 2004 issue of Emerging Infectious Diseases .) Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE), or prion disease, of the same category as BSE. While cattle are the natural hosts for BSE or Mad Cow Disease, deer and Rocky Mountain elk are the only known natural hosts for CWD. CWD and other TSEs are believed to be caused by a pathogenic effect on neurons caused by prion protein. The pathogenic form of this protein appears to be devoid of nucleic acids (genetic material) and supports its own amplification in the host.

CWD was first identified as a fatal wasting syndrome of captive mule deer in the late 1960s in research facilities in Colorado and was recognized as a TSE in 1978. Subsequently, this wasting disease was identified in captive deer and elk in both Colorado and Wyoming . The disease was first recognized in the wild in 1981, and by the mid–1990s, CWD had been diagnosed among free-ranging deer and elk in northeastern Colorado and southeastern Wyoming , and has since spread to adjacent areas in Nebraska . Surveillance data indicate that the overall prevalence of the disease in this area is approximately 5% in mule deer, 2% in white-tailed deer, and <1% in elk. The disease can be highly transmissible within captive deer and elk populations, but the mode of transmission is not clearly understood. Evidence supports lateral transmission through direct animal-to-animal contact or as a result of indirect exposure to prions in the environments, including contaminated food and water sources.

Concerns have been raised about the possible transmission of the CWD agent to domestic animals, such as cattle and sheep, which may come in contact with infected deer and elk or CWD-contaminated environments. If such transmissions were to occur, they would potentially increase the extent and frequency of human exposure to the CWD agent. In ongoing experimental studies, after more than 6 years of observation, no prion disease has developed in 11 cattle orally challenged with the CWD agent or 24 cattle living with infected deer herds. In addition, domestic cattle, sheep, and goat residing in research facilities in close contact with infected cervids did not develop a prion disease.

The increasing detection of CWD in a wider geographic area and the presumed foodborne transmission of BSE to humans, resulting in cases of vCJD (see previous story), have raised concerns about the possible transmission of CWD to humans. In the late 1990s, such concerns were heightened by the occurrence of CJD among 3 individuals who were deer hunters or ate deer and elk meat harvested by family members. However, an investigation into these illnesses indicated no strong evidence for a causal link between CWD and their CJD illnesses. Other cases have also been investigated. In 2001, the case of a 25-year-old man who reportedly died of a prion disease after an illness lasting ˜22 months was investigated. Although this man had hunted deer only rarely, his grandfather hunted deer and elk throughout much of the 1980s and 1990s and regularly shared the venison with the case-patient's family. The grandfather primarily hunted in southeastern Wyoming , around the known CWD-endemic area. The case-patient's illness began with a seizure and progressed to fatigue, poor concentration, and depression and worsening symptoms. A brain autopsy confirmed a prion disease diagnosis, but unrelated to CWD. It remains unknown whether the possible exposure of the case-patient to CWD-infected venison potentially contributed to the early onset of his prion disease. Other cases of CJD have also been investigated for potential links to CWD, but no direct links have been found. Recently, rare neurologic disorders resulting in the deaths of three men who participated in "wild game feasts" in Wisconsin in a cabin owned by one of the decedents created concern about the possible relationship of their illnesses with CWD. Two of the patients reportedly died of CJD, and the third died from Pick's disease. More than 50 persons were identified as possibly participating in these feasts; the three patients were the only participants reported to have died of a degenerative neurologic disorder. Reanalysis of autopsy brain tissues from the three patients at the National Prion Disease Pathology Surveillance Center indicated that two of them had no evidence of a prion disease by immunohistochemical analysis. CJD was confirmed in the third patient, who had participated in the feasts only once, perhaps in the mid-1980s. In addition, the investigation found no evidence that the deer and elk meat served during the feasts originated from the known CWD-endemic areas of Colorado and Wyoming .

Overall, despite the decades-long endemicity of CWD in Colorado and Wyoming , the incidence of CJD and the age distribution of CJD case-patients in these two states are similar to those seen in other parts of the United States . The age of disease onset for infected individuals in the two states is similar to the national average.

In conclusion, the lack of evidence of a link between CWD transmission and unusual cases of CJD, despite several epidemiologic investigations, and the absence of an increase in CJD incidence in Colorado and Wyoming suggest that the risk, if any, of transmission of CWD to humans is low. Although in vitro studies raise the possibility of low-level transmission of CWD to humans, no human cases of prion disease with strong evidence of a link with CWD have been identified. However, the transmission of BSE to humans and the resulting vCJD indicate that, provided sufficient exposure, the species barrier may not completely protect humans from animal prion diseases. Because CWD has occurred in a limited geographic area for decades, an adequate number of people may not have been exposed to the CWD agent to result in a clinically recognizable human disease. The level and frequency of human exposure to the CWD agent may increase with the spread of CWD in the United States . Because the number of studies seeking evidence for CWD transmission to humans is limited, more epidemiologic and laboratory studies should be conducted to monitor the possibility of such transmissions. In the meantime, to minimize the risk for exposure to the CWD agent, hunters should avoid eating meat from deer and elk that look sick or test positive for CWD. They should wear gloves when field-dressing carcasses, bone-out the meat from the animal, and minimize handling of brain and spinal cord tissues. As a precaution, hunters should avoid eating deer and elk tissues known to harbor the CWD agent (e.g., brain, spinal cord, eyes, spleen, tonsils, lymph nodes) from areas where CWD has been identified.

For a full text of the article: Belay ED, Maddox RA, Williams ES, Miller MW, Gambetti P, Schonberger LB. Chronic wasting disease and potential transmission to humans. Emerg Infect Dis. 2004 June. Available from: http://www.cdc.gov/ncidod/EID/vol10no6/03-1082.htm

Dr. Seuss was Right: Green Eggs and Ham are OK!

Don't be alarmed by a bit of green color on hard-cooked eggs or baked ham. The green ring around the yolk of a hard-cooked egg is due to hydrogen in the egg white combining with sulfur in the yolk. This happens when eggs are boiled too hard for for too long, or by high iron levels in the cooking water. Although the green ring is harmless, there is a good chance that you can avoid this discoloration by hard-cooking and not hard-boiling the eggs. The American Egg Board suggests these steps for hard-cooking eggs with best quality:

• Place eggs in single layer in a saucepan and cover with cold tap water, covering the eggs by at least 1 inch.

• Bring the water to boil over high heat, and then turn the burner off.

• Cover the pan, and let sit for 20 minutes.

• Drain the water from the pan and immediately cool with cold water.

• Store hard-cooked eggs in the refrigerator, in an old egg carton works well. Consume within one week.

A greenish tint can sometimes be seen on the surface of sliced meats. The natural occurrence of iridescence, or a rainbow-like ‘mother of pearl' appearance, is sometimes found in fresh beef muscles and often present in cooked or cured meat such as ham and roast beef. While consumers may associate iridescent colors with chemical or bacterial contamination of meat products, the shiny color is not an indication of spoilage. The presence of the sheen is a purely physical phenomenon due to the light being refracted at the surface of the meat, much as would occur when the light passes through a prism. The presence of iridescence is affected by angles of lighting and the orientation of the meat. Some of the contributing factors are the moisture level at the product surface (iridescence decreases as the product dries out) and a thin film of fat smeared across the exposed surface, as well as added substances such as salt and phosphate.

Information on greening in eggs comes from the American Egg Board: www.aeb.org

Update on Food Preservation Trainings

My thanks to those of you who have joined us on the Food Preservation Wislines so far! The questions and comments that have come in have been very interesting. As you think of ideas that you would like to share, please let me know. I know that my garden is behind with all the rain that we have had in the state, but I am hoping that it will catch up soon and there will be garden produce to process.

Updated schedule. Due to a travel commitment for my husband on one of the scheduled Fridays, I have had to move the date for one of the Wisline programs. An updated schedule follows with changes in bold:

6/11 Drying Foods at Home 10:30-11:30
6/25 Canning Low Acid Vegetables 10:30-11:30
7/9 Tomatoes Tart and Tasty! 10:30-11:30
7/16 Canning Fruits Safely 10:30-11:30 (this topic was added to take advantage of those wishing to can fresh peaches and pears ripening mid-summer)
8/6 Canning Salsa Safely 10:30-11:30 (date change for this topic)
8/20 Pickles and relishes 10:30-11:30 (date change for this topic)
9/10 Storing Garden Produce 1:30-2:30
10/8 Canning Meat 1:30-2:30
11/12 Making Jerky & Sausage 1:30-2:30
12/10 Holiday Food Gifts 1:30-2:30
As always, I will send out email reminders and there will be power point slides developed to accompany each program. I am working on web development this summer and these programs will all be posted to the web. Again, your ideas or comments are most welcome!

Press releases. Jo Futrell is working with me on a series of press releases to accompany this summer programming. A total of 9 releases are being edited and finalized the first week of June. Look for those and please let me know if you have questions or comments. As always, thank you for your input!

Supplies for canning. One point of discussion during our Wisline programs has been where to obtain supplies such as pectin (bulk) and citric acid for canning. Here are potential sources for these items:

Citric acid (for acidifying canned tomato products)

• Kitchen Krafts http://www.kitchenkrafts.com/ or 1-800-776-0575
IN0002 Citric Acid, 5 oz. $2.80

• Canning Pantry.com http://www.canningpantry.com/citric-acid.html
Citric Acid, 5 oz. $2.97 (sufficient for 50 quarts of tomatoes)

Pectin (bulk)

• Kitchen Krafts www.kitchenkrafts.com/ or 1-800-776-0575
IN1511 Regular Gel-Ez pectin mix, 1 lb. $9.25 (also available in 10 and 50 lb. bags)

IN1521 Lite Gel-Ez pectin mix, 1 lb. $13.25 (also available in 10 lb. bags)

And, as a reminder, 1/3 cup of bulk pectin mix replaces 1 standard box.

Safe Preparation of Infant Formula

You may have heard of a recent FDA warning related to possible bacterial infection in hospitalized infants fed powered infant formulas. The illness is associated with the bacterium Enterobacter sakazakii which survives the process used to prepare dry formula and can cause illness in immuno-compromised infants in hospital settings. The bacterium causes sepsis or meningitis in premature infants or other infants with weakened immune systems. The warning does not apply to liquid forms of infant formula. And even though healthy, full term infants do not appear to be at risk, I thought it might be a good time to repeat recommendations for safe preparation of infant formula.

Safe Preparation of Infant Formula

1. Wash and sterilize bottles and nipples.
2. Concentrated Liquid- wash the top of the can with hot soapy water and rinse well. Wash the can opener. Shake the can well, open, and mix with one can of cooled boiled water. Open cans of ready-to-eat and liquid concentrate must be refrigerated.
3. Powdered- For each 2 ounces of water, add 1 level scoop of powdered formula to a clean, sterile bottle. For Moms on the go, pre-measure water in bottles and add formula as needed. (Note: the American Academy of Pediatrics no longer recommends the use of boiled, cooled water in the preparation of infant formula. Water from the tap, as long as it is not high in nitrates, is deemed appropriate for reconstituting dry powdered formula. 10/2002.)
4. NEVER under-dilute formula as this can cause problems for the infant's organs and digestive system. Over-diluted formula will not provide adequate nutrition, and baby may fail to thrive and grow.
5. Attach nipple to bottle and shake well. Feed prepared formula immediately or refrigerate for no more than 48 hours.
6. Prepared formula may be warmed under warm tap water. A microwave oven is not recommended for warming baby formula because hot spots and overheating can result.
7. Throw away formula left in the bottle after each feeding. Do not let prepared infant formula sit at room temperature for more than 2 hours. Carry an ice pack, if needed, in the diaper bag so that formula stays cool. Warm under running water before feeding to baby.
8. Always the check the temperature of warmed formula before feeding. Shake a few drops on the top of your hand, formula that is just warm to the skin is the proper temperature for baby. Always check the temperature of the formula itself and not just the container.

What's on Your Mind?

Converting conventional recipes for microwave cooking. With the increasing popularity of microwave cooking, Pam Schotz ( Lincoln County administrative assistant) asked for an easy reference for converting conventional recipes for the microwave. While I didn't have a complete guide, the Handbook of Food Preparation that many of you may have in your offices has a section entitled Microwave Cooking Basics which has some basic information in this area. If you don't have a copy of that information, I'll be happy to fax or mail it to you.

Perfectly ripe fruits. The summer months bring a wide variety of fruits to orchards and market stands. Often these fruits are perfectly ripe and ready to eat. But many fruits, even if they are under-ripe, can be coaxed to ripen for fuller flavor. Fruits that will respond to ripening at home include apples, apricots, avocadoes, bananas, figs, mangoes, muskmelon, papaya, peaches, pears, persimmon, plums, tomatoes and watermelon. To encourage ripening, store these fruits in a paper bag on the counter and place an apple inside the bag. Apples produce a gas known as ethylene that helps to ripen fruit. The paper bag traps the gas, while preventing moisture from building up like a plastic bag would. Once the fruit is ripe, refrigerate in a produce storage container to help preserve freshness and prevent decay. Don't wash fruits before storage, as excess moisture will encourage mold growth, wash only when ready to eat.

Produce de-coded. Have you ever wondered what the 4 or 5 digit code means on some fresh produce that you find in the grocery store? Well, thanks to a question, I now know the answer! The code is part of the PLU, or Please Look Up, system developed as a way of dealing with the many varieties of similar fruit and vegetables. The system is voluntary, but has some real advantages. Some of the differences between a Braeburn, Fuji and Gala apples can be subtle, especially to the young teenager running the checkout system, and how do you tell the difference between an 88 size California navel orange versus a 72 size one? So, the codes can be used to differentiate between different sizes or varieties of produce.

But you can also use the code to figure out how the product you're buying has been grown. A sticker with four digits means the food was conventionally grown. Five digits starting with an 8 indicates genetically engineered produce, and 5 digits starting with a 9 means the food was organically grown. COOL legislation (Country of Origin Labeling) will probably be coming soon where the country of the produce would have to be on the retail product . For more information, check out this web site:. www.PLUCODES.com

Tips, tools and travel-safe food for summer food safety. Alice Henneman at the University of Nebraska-Lincoln has prepared some ideas for summertime food safety. Please check those out http://lancaster.unl.edu/food/ftjun04.htm along with seasonal resources from Wisconsin FIRST: http://www.wisc.edu/foodsafety/wfseasonal.htm .

Ultra Bleach. With concentrated bleach, ultra bleach, becoming ever more popular I wanted to repeat information that I had shared several years ago on preparing a dilute sanitizer using ‘ultra' bleach. Ultra bleach contains 6% sodium hypochlorite, rather than the standard 5.25% in 'regular' bleach. Here are the proportions for preparing a standard solution using both types of bleach.

Ultra (6%) bleach	2-1/2 teaspoon per gallon; 3/4 teaspoon per quart
Regular (5.25%) bleach	1 Tablespoon per gallon; 1 teaspoon per quart