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The EU and US positions at a Codex meeting to set international standards on food safety foreshadow future legislation that would affect hygiene control measures in manufacturing plants, and the manufacture of powdered formulae, ready-to-eat foods, and pasteurised liquid eggs.

In the six day meeting which ended on the 4 November in New Delhi, India, national representatives to Codex’s food hygiene committee also decided to start work on drafting safety guidelines setting standards to control Campylobacter and Salmonella specie in broiler chicken meat.

At the New Delhi meeting they discussed various positions, including those relating to proposed standards for pasteurized liquid whole eggs, hygienic practice for processing powdered formulae for infants and children, pathogen control measures for Listeria monocytogenes in ready-to-eat foods & guidelines for evaluating manufacturing control measures.

Codex is a multilateral body set up to develop food safety and other standards that would apply to all member countries.

It operates under the aegis of the UN’s Food and Agriculture Organisation and the World Health Organisation.

The standards are recognised as international benchmarks by one of the multilateral agreements of the World Trade Organisation (WTO) and aim to eliminate many of what the UN calls “unjustified technical barriers” to food imports set up by some countries.

The standards also serve to harmonise food safety laws globally, aiding multinational processors in following the law no matter where they trade.

The standards on each particular topic and food type can undergo a huge revision process at various levels of Codex decision making bodies, over a number of years. Member countries must then transcribe the standards into their national laws.

The proposed standard setting what pathogen controls for Listeria monocytogenes ready-to-eat food processors must put in place is based in the main on US risk assessments, according to Codex documents.

Based on the risk assessments, a working group led by Germany concluded that a zero tolerance standard for L. monocytogenes have a proportional reduction in the rates of illness from foods contaminated with the pathogen.

A study commissioned by the food hygiene committee showed that the application of microbiological criteria at a given point of the production chain is only one of the measures that need to be applied, to bring down contamination rates.

The committee proposes to exclude from the criteria foods that are processing in such a way to ensure the killing of L. monocytogenes and for which recontamination is not possible.

The foods must also be processed and handled under systems adhering to good hygienic practice (GHP), a separate international standard.

Such foods include those given a listericidal treatment in the package and those that are produced through aseptic processing and packaging.

The group includes dehydrated products such as powdered milk, dehydrated soup mixes, herbs and spices, fresh, uncut and unprocessed vegetables and fruits, soft drinks, beer and spirits.

At the meeting the EU delegation also proposed that the standard should specifically include ready-to-eat foods for infants and those with medical conditions.

The EU supports a 100 colony forming units per gram (cfu/g) limit on the pathogen for ready-to-eat foods, if the food manufacturer is able to demonstrate the maximum would not be exceeded throughout the shelf-life.

The EU delegation also noted that setting a zero tolerance standard, where a negative reading is set at 25g = 0.04 colony forming units per gram (cfu/g) “might cause misunderstandings”.

The EU also wants clarification on foods not covered by the testing standard, pointing out that previous discussions had also discussed products for which Listeria monocytogenes is “very unlikely” to be detected.

Clarification is also needed about the proposed exclusion of foods for which there is less than ‘1 log’ growth during 1.3 times the expected shelf life, the EU stated in its submission. Various definitions of ’shelf-life’ might confuse the issue.

At the meeting the Codex committee also set its priorities for proposed standards, with those for egg products topping the list.

Other priorities in order are standards for infant and children foods; combining two codes of practice for various nuts into one; setting a single hygienic code for fruits, vegetable and products made from them; quick frozen foods, spices and aromatic plants; low-acid and acidified low-acid canned foods and aseptically processed and packaged low-acid canned foods, natural mineral waters, frog legs, catering, and street-vended foods.

The WTO’s Codex Alimentarius Commission is the body set up to harmonise food safety and other export requirements around the world.

Member countries’ representatives meet regularly to debate a common position or standard on every aspect of such requirements, from the holding temperatures in frozen meat should be kept at, to processing requirements for specific types of cheeses.

Agreements forged at Codex meetings could eventually affect the way processors operate worldwide as they become incorporated into national laws in various countries around the world.

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While America’s food supply is the safest in the world, food poisoning is responsible for approximately 76 million illnesses in the United States each year. In fact, it is estimated that 60% or more of the raw poultry sold today probably has disease-causing bacteria. Anyone eating food contaminated by certain bacteria, parasites, or viruses can get food poisoning. Certain factors such as age and physical condition can make certain people more susceptible to food poisoning than others. Infants, pregnant women, the elderly and people with compromised immune systems are at greatest risk.

For most people in good condition, food poisoning is usually neither long lasting nor life-threatening. However, to less healthy individuals it can become a serious health threat, accounting for approximately 5,000 deaths each year.

The good news is that by taking simple precautionary steps while purchasing, handling, and preparing food you can prevent most cases of food poisoning in the home.

What causes food poisoning? Food poisoning is most commonly caused by bacteria, parasites, or viruses that may be present in the food that you have eaten. You may have heard the names of many of these organisms. They include Escherichia coli (E coli), Campylobacter jejuni, Clostridium botulinum, Shigella, Salmonella, Staphylococcus aureus, Trichinella, and Hepatitis A virus, just to name a few. They can be present in a wide range of food including red meat, poultry, milk and other dairy products, eggs, unpasteurized vegetable juices and ciders, spices, chocolate, seafood, and even water.

These organisms may be present on your food when it is bought or can get into the food, including cooked food, if the food comes into contact with raw meat juices on dirty utensils, cutting boards, or countertops used to prepare contaminated food. That’s why it is important not only to thoroughly cook your food, but to wash your hands, utensils, and countertops, before and after you handle raw foods.

What are the symptoms? Symptoms will vary depending on the type and amount of contaminants eaten. Some people may get ill after ingesting only a small amount of harmful bacteria, while others may remain free of symptoms after eating larger quantities. The most common symptoms of food poisoning include nausea, vomiting, diarrhea, stomach pain (cramps), fever, headache, and fatigue. Symptoms may develop as soon as 30 minutes after eating tainted food, but more commonly do not develop for several days or weeks. Symptoms of viral or parasitic food poisoning may not appear for several weeks, while some toxins in fish may take only a few minutes to cause symptoms.

If you have botulism, you probably will not have a fever and the symptoms may include blurred vision, fatigue, dry mouth and throat.

How food poisoning is diagnosed Food poisoning is often suspected when several people become ill after eating the same meal. To diagnose the cause of the illness, your doctor will need to know the symptoms and what was eaten right before the illness occurred. The doctor may need samples of the food, bowel movements, or vomit. These samples can be tested in a laboratory to determine if the food was contaminated and identify the organism causing the illness.

How is it treated? If the symptoms are severe, the victim should see a doctor or get emergency care. Treatment depends on the severity and cause of the food poisoning. Generally, for mild cases of food poisoning, the doctor will recommend for you to rest, drink fluids to prevent dehydration due to vomiting or diarrhea, and to follow a specific diet. It usually only takes about 1 to 5 days to recover from food poisoning.

If you have botulism, your doctor will prescribe an antitoxin. Other types of food poisoning have no antidote. Antibiotics are usually not helpful in treating food poisoning. Medicine to stop vomiting and stomach cramping may be given.

Prevention is the best approach to avoid food poisoning Most cases of food poisoning can be prevented. Below is a list of a few simple Do’s and Don’ts to help you avoid food-borne illness in the home.

● Do wash your hands, utensils, cutting boards, and countertops between different foods ● Do hrefrigerate or freeze perishables right away (Refrigerator temperature should be 41Ëš F and freezer 0ËšF) ● Do thoroughly cook foods. Cook beef, lamb, and pork to an internal temperature of 160ËšF; whole poultry and thighs to 180ËšF; poultry breasts to 170ËšF, ground chicken or turkey to 165ËšF ● Do hrefrigerate leftover foods as soon as possible; leftovers shouldn’t remain unrefrigerated longer than 2 hours. ● While food shopping, do select frozen foods and perishables such as meat, poultry, and fish last- before checking out ● Do use smooth cutting boards made of hard maple or plastic that are free of cracks and crevices ● Do store raw meats in leak-proof containers or on the bottom of the hrefrigerator to prevent juices from dripping on other foods ● Don’t allow uncooked meats, meat juices, or unwashed fruits and vegetables to come in contact with either cooked or washed foods ● Don’t buy frozen seafood if the packages are open, torn, or crushed on the edges ● Don’t buy food in cans that are bulging or dented, or in jars that are cracked ● Don’t ever buy outdated food. Check the “use by” or “sell by” dates ● Don’t buy unpasteurized milk or dairy products ● Do not buy hrefrigerated or frozen products that are not displayed at the proper temperature ● Do not let small children put foods away unsupervised

More information about this important health subject can be obtained from the following sources: Gateway to Government Food Safety Information www.foodsafety.gov U.S. Food and Drug Administration Center for Food Safety and Applied Nutrition http://vm.cfsan.fda.gov/~dms/wh-food.html Food Safety and Inspection Service United States Department of Agriculture www.fsis.usda.gov/OA/pubs/consumerpubs.htm

Supported as an educational service by Novartis Pharmaceuticals Corporation. This information is not intended for use as medical advice. You should discuss this information with your doctor.

Avaraham Henoch, MD 564 West 160th Street New York, NY 10032 Phone: (212) 740-6400

According to the Washington Post, a virulent strain of bacillus tuberculosis which is resistant to most available antibiotics is appearing around the world. This has started to raise fears of a pandemic that could devastate efforts to contain the tuberculosis and prove deadly to people with immune-deficiency diseases such as HIV-AIDS or the immuno-compromised.

The strain known formally as extensively drug-resistant tuberculosis or XDR- tuberculosis has been detected in 37 different countries.
It arises when the bacillus bacterium that causes tuberculosis mutates because antibiotics used to destroy it are carelessly administered at a lower level by poorly trained doctors or patients don’t complete their full course of medication. Therefore, rather than being killed by the drugs, the microbe mutates and builds up resistance.

This strain has a high mortality rate and at least 50 percent of those who contract this strain of tuberculosis will die of it.

In the United States, 13,767 tuberculosis cases were recorded in 2006, the lowest rate of infection since reporting began in 1953. A retrospective analysis by the CDC found 49 cases of the new strain in the country since 1993.

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According to the China Daily, Chinese scientists have cracked the biological codes of a heat tolerant bacterial strain that feeds and metabolized on crude oil. This strain could be further developed so that it may be an environmentally method used to clean oil spill.

The strain, Geobacillus thermodenirificans NG80-2 was initially isolated from an oil well in Dagang Oil Field (North China’s Tianjin area). Initial studies have shown that it can grow at temperatures between 45-73 C with crude oil being the sole energy source.

Researchers at Nankai University in Tianjin determined the genetic sequence of the bacterial strain after almost three years of experiments, and discovered its metabolic pathway.

“We identified the key enzyme that enables the bacterium to degrade long-chain alkanes, a chemical component of oil, to smaller molecules,” said Wang Lei, a lead scientist of the research team at Nankai University.

“We also discovered a simple way to isolate the enzyme.”

Wang and his colleagues found NG80-2 produced large amounts of a protein called LadA, which performed the first step in the degradation of long-chain alkanes.

Long-chain alkanes are used as lubricant and fuel oils, their existence chemically differentiating heavy oil from light oil which consists of shorter-chain alkanes. Heavy oil is usually more viscous and difficult to extract or remove.

The research results were published in this week’s US journal Proceedings of National Academy of Sciences online; and the scientists suggest in their report that the protein is an “ideal candidate” for treatment of environmental oil pollution.

The sequence analysis also suggests the bacterial strain can adapt to many different environmental niches since it involves versatile metabolic processes, which add to its potential in many biotechnology applications.

Current microbial approaches to degradation of oil pollutants are of low efficiency, and mostly apply to light oil, according to Wang, professor and dean of TEDA School of Biological Sciences and Biotechnology at Nankai University.

“More importantly, they are used in a context that no definite knowledge about how the bacteria work is available,” he said. “With the identification of this protein, we can upgrade it or alter it to various applications and improve efficiency of its performance.”

The research team has started looking into the three-dimensional structure of the protein and tested it in a field experiment on oil pollutant degradation.

Wang believes a wider application of the protein would be realized in two to three years. In addition to oil pollutant removal, oil extraction is another potential field for its application, he added.

US Department of Energy data has shown that the microbial approach can improve oil extraction efficiency by 10 to 15 percent and sustain the development term of oil reserves by five to 10 years.

Science Daily, a Beijing-based newspaper, has reported that pilot field experiments at Shengli Oil Field had helped increase cumulative oil production by about 60,000 barrels by 2005.

But Han Xuegong, a retired professor at China National Petroleum Corporation Managers Training Institute, warns that laboratory success does not necessarily guarantee industrial usage. “Cost plays a crucial role,” he said.

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In most languages, sentences only make sense if the words are placed in the right order. Now, MIT researchers and an IBM colleague have used grammatical principles to help their search for new antimicrobial medicines.

After identifying “grammatical” patterns in naturally occurring antimicrobial peptides, the researchers custom-designed molecules that proved extremely effective in killing microbes, including anthrax bacteria. The research could lead to new medicines to combat deadly drug-resistant bacteria.

“In the last 40 years, there have been only two new classes of antibiotic drugs discovered and brought to the market,” said graduate student Christopher Loose, lead author of a paper on the work that appears in the Oct. 19 issue of Nature. “There is an incredible need to come up with new medicines.”

Loose, research associate Kyle Jensen and Professor Gregory Stephanopoulos of the Department of Chemical Engineering are focusing their attention on antimicrobial peptides, or short strings of amino acids. Such peptides are naturally found in multicellular organisms, where they play a role in defense against infectious bacteria.

The researchers’ newly designed peptides were shown to be effective against dangerous microbes such as Bacillus anthracis (anthrax) and Staphyloccus aureus, a bacteria that spreads in hospitals and is frequently drug-resistant. The peptides may also be less likely to induce drug resistance in these bacteria, according to the researchers.

Antimicrobial peptides act by attaching to bacterial membranes and punching holes in them, an attack that is general to many different types of bacteria and is difficult for them to defend against. “There’s no quick easy mutation fix for a bacteria to get around this non-specific membrane attack,” said Loose.

The peptides are generally short, consisting of about 20 amino acid building blocks. The molecules naturally fold into a helix, with positively charged areas running along one side of the helix and hydrophobic (water-resisting) areas along the other side. The charged ends allow the peptides to latch onto the bacteria by attracting the negative charges of the bacterial membrane, while the hydrophobic ends punch holes in the membrane.

Because there are 20 naturally occurring amino acids, there are about 1026 possible peptide sequences of length 20. Some of those kill microbes with varying levels of effectiveness; the overwhelming majority have no effect.

With such a mind-boggling number of possible combinations, it is extremely difficult to find effective antimicrobial peptides by using traditional methods such as testing random sequences or slightly tweaking naturally existing peptides. “Designing them from scratch is quite difficult,” said Loose.

Instead, the researchers decided to take a more strategic approach, based on grammatical patterns in the peptide sequences.

At its essence, a “grammar” is a simple rule that describes the allowed arrangements of words in a given language. As it applies to peptides, the sequence can be thought of as a sentence, while the individual amino acids are the words. For example, the sequence QxEAGxLxKxxK, where x is any amino acid and Q, E, A, etc. are specific amino acids, is a pattern that occurs in more than 90 percent of a certain class of insect antimicrobial proteins known as cecropins.

In this case, the researchers, led by Jensen and Isidore Rigoutsos of IBM Research (Rigoutsos is also a visiting lecturer in the Department of Chemical Engineering), used a pattern discovery tool to find about 700 grammatical patterns in the sequences of 526 naturally occurring antimicrobial peptides.

To design their new peptides, the researchers first came up with all possible 20-amino acid sequences in which each overlapping string of 10 amino acids conformed to one of the grammars. They then removed any peptides that had six or more amino acids in a row in common with naturally occurring peptides. Then, they threw out sequences that were very similar to each other and chose 42 peptides to test.

About half of the peptides displayed significant antimicrobial activity against two common strains of bacteria — Escherichia coli and Bacillus cereus. That is a much higher success rate than one would expect from testing randomly generated sequences, and much higher than the success rate for peptides with the same amino acids as the designed sequences, but in a shuffled order.

“We’ve been able to focus our shotgun approach so that half of the time, we get a hit,” said Loose.

In further tests, two of the designed peptides showed very high effectiveness against two types of especially dangerous bacteria, S. aureus and anthrax.

The researchers have already begun using their technique to further refine the most effective peptides by tinkering with the sequences and altering traits like charge and hydrophobicity. They hope this process will eventually lead to new, more effective antimicrobial medicines.

The research was funded by the Singapore-MIT Alliance, the National Institutes of Health and the Fannie and John Hertz Foundation.

Source: WebWire - Anne Trafton

Bacillus stearothermophilus or Geobacillus stearothermophilus is one of the most common spoilage bacterium in commercially sterile heat processed foods. Although most bacterium cannot survive the high temperature, Bacillus stearothermophilus has a highly heat resistant spores that has enabled this bacterium to spoil canned foods, UHT milk, and other commercially sterile foods.

So what temperature is required to kill this bacterium? How long must it be held at this temperature?

A measure used to determine the effective kill rate is called the D or D’ Value. Basically, the D Value measures the time in minutes required at a given temperature for destruction of 90% of the cells.

Although it sounds simple, it’s not. It also depends on the nature of the food product, the pH, the salt level and so forth. For example, the lower the pH, the lower the temperature required. The higher the pH or close to a neutral pH of 7, the higher the temperature is required to kill this bacterium.

Below is a graph showing the thermal inactivation of Bacillus stearothermophilus spores (ATCC 12980).

For more detailed information you can download the pdf file here on the Thermal Inactivation and Injury of Bacillus Stearothermophilus Spores.

Bacillus licheniformis is a Gram-positive motile spore-forming rod, facultative anaerobic and belongs to the Bacillus subtilus group of Bacilli. It is an apathogenic soil organism that is mainly associated with plant and plant materials in nature but can be isolated from nearly everywhere in natures such soil, water, food manufacturing plant and so forth. Although its spores are highly heat resistant (100.C for 30 minutes), it is not as resistant as Bacillus stearothermophilus.

Although very very rare, Bacillus licheniformis has been associated in food poisoning in humans with foods such as cooked meat, poultry and vegetable dishes (particularly stews and curries which have been served with rice). Again this is a rare occurrence and not a major concern. Food poisoning by Bacillus licheniformis is characterized by diarrhea, although vomiting occurs in half of reported cases.

Bacillus licheniformis produce proteases and amylases which at high levels can cause the breakdown of short shelf-life foods with starch such as custards, rice puddings, sauces and so forth. Industrially the enzymes produced by Bacillus licheniformis have been extracted for use in household detergents. In the U.S. about 50% of liquid detergents, 25% of powder detergents, and almost all powdered bleach additives now contain enzymes to help break down stains that are otherwise hard to remove with conventional surfactants alone.

Bacillus licheniformis produce also produces penicillinase, pentosanases, bacitracin, proticin, 5′inosinic acid and inosine, citric acid, and substituted Ltryptophan.

Bacillus licheniformis is also a common dairy contaminant being present in raw milk. Monitoring of incoming raw milk for spores is an effective method of determining whether bacillus spores are present in the milk supply. The species has been isolated in pasteurized milk and cream where it can cause bitterness due to the protease enzymes breaking down the milk protein. It has also been reported as a contaminant in UHT milk as well. Although it is very unlikely to survive the UHT sterilization process, it may reside in the environment within the manufacturing plant and therefore Good Manufacturing Practice (GMP) will ensure its prevalence is the environment is reduced. Areas may include dirty valves, seals, heating plates, air vents and so forth.

Bacillus licheniformis also causes ropiness in bread and again monitoring the spore levels in flour may be an effective method of determining whether bacillus spores are present in flour used.

Bacillus licheniformis optimum growth temperature is 30.C; however it will not grow at low pH.

Bacillus No Synopsis Available

Bacillus cereus is a gram positive rod that produces spores and has been recognized as an agent of food poisoning since 1955. There were 52 food poisoning outbreaks between 1972 and 1986 associated with Bacillus cereus were reported, however this is thought to only represent 2% of the total cases which have occurred during that time.

Bacillus cereus causes two types of food poisoning compared to bacterial infections. The first is characterized by nausea and vomiting and abdominal cramps and has an incubation period of 1 to 6 hours. This closely resembles Staphylococcus aureus enterotoxin food poisoning in its symptoms and incubation period and is called emetic toxin and or the “short-incubation”. This is caused by a preformed heat-stable enterotoxin of molecular weight less than 5,000 daltons. The mechanism and site of action of this toxin are unknown. The long-incubation form of illness is mediated by a heat-labile enterotoxin (molecular weight of approximately 50,000 daltons) which activates intestinal adenylate cyclase and causes intestinal fluid secretion.

The short-incubation form is most often associated with fried rice or starchy foods that has been cooked and then held at warm temperatures for several hours. The disease is often associated with Chinese restaurants. In one reported outbreak, macaroni and cheese made from powdered milk turned out to be the source of the bacterium.

The second type of food poisoning results primarily in abdominal cramps and diarrhea with an incubation period of 8 to 16 hours. Diarrhea may be a small volume or profuse and watery. This type is referred to as the “long-incubation” or diarrheal form of the disease, and it resembles more food poisoning caused by Clostridium perfringens. This type of food poisoning is frequently associated with meat or vegetable-containing foods after cooking. The bacterium has been isolated from 50% of dried beans and cereals and from 25% of dried foods such as spices, seasoning mixes and potatoes. One outbreak of the long-incubation form was traced to a “meals-on-wheels” program in which food was held above room temperature for a prolonged period.

The short-incubation or emetic form of the disease is diagnosed by the isolation of Bacillus cereus from the incriminated food. The long-incubation or diarrheal form is diagnosed by isolation of the organism from stool and food as well as the toxin using ELISA based kits such as TECRA.

An unsatisfactory level of Bacillus cereus in cooked foods generally occurs as a result of inadequate temperature control.

As for Clostridium perfringens, cooked foods should be held at or above 60ºC or at or below 5ºC to prevent growth, or held outside this temperature range for a limited time. Foods associated with Bacillus cereus food poisoning include cooked rice dishes, other cereal based foods such as pasta/noodles, dairy based deserts and meat or vegetable dishes incorporating spices. The detection of high levels (>1000 cfu per gram) of Bacillus cereus should result in an investigation of the food handling controls used by the food business.

Levels of ≥10000 cfu per gram are considered potentially hazardous as consumption foods with this level of contamination may result in food borne illness. Other Bacillus species, such as Bacillus subtilis and Bacillus licheniformis, have also been associated with food borne illness and may also be tested for using microbiology consulting labs.

Have you ever questioned why pasteurized milk sometimes spoils before the best before code whilst being stored in the fridge? At the same time, it is accompanied by a slight rancid odor as well.

Interestingly it is caused by the presence of a group of bacteria that loves living in the cold environment; these are called psychrotrophs or psychrotrophic bacteria. Pseudomonas is one of the most common within the group and interestingly this is the same bacterium that causes spoilage (slimy layer) in raw chicken during refrigerated storage.

Did you know that even if you keep the milk chilled within the recommended storage temperature, a single cell of pseudomonas can multiply to over a million cells in the space of just six days? Even one of this bacterium in a carton of milk can cause a spoilage problem.

So how do these bacteria enter the milk even though the milk is pasteurized! Easily, it’s due to poor hygiene by the manufacturers because if it is pasteurized and packaged hygienically there should not be any spoilage bacterium present at all, nada!

The only bacterium that can survive the heating process is heat resistant bacteria such as bacillus species and these types will not grow at the refrigeration temperature. Hence there is not premature spoilage.