FOOD SAFETY
Food Storage
FAQ - Contents
Molds in Food
Molds are fungi just like mushrooms and yeast. Also like mushrooms, they reproduce by releasing spores into the air that land on everything, including your food and food storage containers. When those spores begin to grow, they create thin threads that spread through out their growing medium. These threads are the roots of the mold fungus, called mycelium. The stalk of a mold fungus is the portion above or on the surface of the food. It produces the spores and gives the mold its color. We've all seen examples of this when we discover a dish of something or other left way-y-y too long in the refrigerator and has become covered in mold fuzz.
Molds can grow anywhere they have a growing medium (their food), sufficient moisture and enough warmth. Some can even grow at refrigerator temperatures, albeit more slowly than they would if it were warmer. They can also withstand much more salt and sugar than bacteria, which is why you sometimes find mold in jellies and jams with their high sugar content and on cured products like ham or bacon with their high salt content.
In the past, it was often felt a slight amount of mold was harmless and the food could be consumed anyway. For molds that were intentionally introduced into the food, such as the mold in bleu cheese, this is just fine. For the unintentional molds, it can be a very serious error in judgment. These unwanted molds might just be producing a toxic substance called a "mycotoxin" which can be very bad indeed. Mycotoxins are produced around the root or mycelium of the mold and the mold roots can penetrate very deeply into the food. These mycotoxins can survive for a long time in foods, and unfortunately most are not destroyed by cooking. The molds probably best known for this are the various Aspergillus varieties which produces a mycotoxin known as "aflatoxin", but there are other dangerous molds as well, such the Fusarium molds. Both of the above affect grain and some legumes.
IMPORTANT NOTE: In wet pack foods such as your home canned goodies, molds can do something else, possibly leading to lethal consequences. If they are present in wet pack food by reasons of improper procedure or contamination after the fact, they can consume the natural acids present in the food. The effect of this is to raise the pH of the food in the container, perhaps to the point that it becomes possible for spores of Clostridium botulinum, better known as "botulism", to become active and reproduce. If you're not already aware of the consequences of botulism poisoning, please read the bacterial spoilage section below where it has an entry all its own. There are few kinds of food poisoning with as deadly serious consequences. For this reason, moldy wet pack foods should be safely discarded.
Bacterial Spoilage
Just like the fungi, bacteria are everywhere. They're in the water, soil, air, on you, your food and your food storage containers. Fortunately, the vast majority of the bacteria we encounter are relatively harmless and only a few represent a danger to us and our stored foods.
Bacteria can be very much more difficult to kill off than molds and insects. Some of them are capable of continued growth at temperatures that would kill other spoilage organisms. When conditions are such that they are unable to grow, some bacteria can go dormant and form spores. These spores can be quite hardy, even to the point of surviving a rolling boil.
In order to grow, bacteria need moisture, some as little as a 20% moisture content. For dry grains, legumes, powdered milk and other low moisture foodstuff bacterial spoilage will seldom be a problem so long as the moisture level in the foodstuff remains too scant to support its growth. For this reason, it is imperative that such products be drier than 20% and preferably below 10% to ward off mold growth as well. The botulism bacteria need moisture in the 35% range to grow. Thus, using desiccants in your food packaging is also an excellent idea.
WARNING: It is in wet pack canned goods (where the container has free liquid in it) and fresh foods we must be the most concerned about spoilage bacteria. It is here that a little bad luck and a moment's inattention to what you are doing could kill or seriously injure you or some other person who eats the foods you've put by. In both home-canned and commercially-canned goods, IF THE CAN IS BULGING, LEAKING, SMELLS BAD, OR SPEWS LIQUID WHEN YOU OPEN IT THEN THROW IT OUT! But, throw it out safely so that children and animals cannot get into it.
Botulism
Clostridium botulinum is one of the oldest types of life forms found on the planet. Like the gangrene bacteria, it is an anaerobic organism meaning it lives and grows in the absence of free oxygen. It forms spores when conditions are not suitable for it to grow and it is commonly found in the soil. This means it can be brought into your life on raw produce, tools, hands or anything else that came into contact with dirt. To further complicate matters, botulinum spores are extremely heat-hardy. The bacteria itself can be killed by exposing them for a short time to boiling water (212 F AT SEA LEVEL PRESSURE), but their spores can not. To kill them, the food product and container must be exposed to temperatures of 240 F (AGAIN AT SEA LEVEL PRESSURE) for a long enough period of time to allow all of the food in each container to come completely up to the proper temperature. Only a pressure canner can reach the necessary temperature.
It's not the bacteria or its spores which are directly deadly, but the toxin the bacteria creates when it grows and reproduces. In its pure form, botulism toxin is so potent that a mere teaspoon of it would be enough to provide a fatal dose to hundreds of thousands of people. It is this lethality that is why every responsible book on canning, food preservation, food storage, and the like hammers constantly on the need for care in technique and method and why spoilage must be taken so seriously.
C. botulinum, like any other life form, must have suitable conditions for it to grow and become a danger to you. One of the conditions it must have is a suitable pH range in its environment. pH is the measure of the acidity or alkalinity of a substance and is measured on a scale of 1-14 with anything above 7 being considered alkaline and everything below 7 being considered acid. If the pH of your wet pack food is BELOW 4.6 then botulism is unable to grow. Keep in mind pH is not eternal in foods and it is possible for it to change. If it should change to a lesser acidity than 4.6 pH your previously botulinum-proof food may start allowing the lethal spoiler to grow (see molds in canned goods). This is why it is vital to use proper technique, even for acid foods like tomatoes. It has been found that when this occurs and botulinum becomes active and produces its lethal toxin it also produces minute amounts of acid which can lower the pH of the poisoned food back into what should have been the safe zone had the pH not jumped up and allowed the bacteria to grow. Again and again -- use good technique and pay attention to what you are doing.
Botulinum toxin, unlike fungal mycotoxins, can be destroyed by boiling the food briskly in an open vessel for fifteen minutes. Because of this, if your canned food shows any safety problems you should follow this procedure. If the food shows even the slightest mold growth, keep in mind that mycotoxins are not for the most part broken down by heat and dispose of the food safely.
http://www.survival-center.com/foodfaq/ffaqtoc.htm
How do I know which foods are safe to use after a power-outage?
Generally speaking, if the power has been out for less than four hours, or if the food has been held at 40°F or less, the food is safe to use. Discard any perishable foods such as meat, poultry, fish, eggs, and leftovers that have been above 40° for more than 2 hours or has an off odor, color, texture, or if it feels warm to the touch. For more information about food safety during a power outage visit http://www.fsis.usda.gov/Fact_Sheets/Keeping_Food_Safe_During_an_Emergency/index.asp
How long after I purchase eggs is it safe to use them?
Eggs are safe to use for approximately 4 to 5 weeks past the printed date on the carton. The longer past the date, however, the better it is to use the eggs as either scrambled eggs, hard-boiled eggs or in a recipe. For valuable information on egg safety visit the American Egg Board's website at http://www.aeb.org/.
Is it safe to thaw frozen meats on the counter?
Never allow foods to defrost at room temperature or in warm water. Instead, use your refrigerator to thaw foods by moving them from the freezer to the refrigerator one or two days before you plan to cook them. For a turkey or large cut of meat allow 24 hours of thawing time for every five pounds. An alternative method for thawing is a microwave oven. However, if thawing is done in a microwave oven, the thawed food must be cooked immediately afterward. For more information on handling food safely visit http://www.fightbac.org.
How can I protect my child from food borne illness while in day care?
Make sure that the people who run the day care center practice appropriate sanitation and food handling techniques. You and the care providers should teach children to wash hands with warm, soapy water before and after going to the bathroom. It is critical for childcare providers and parents to remember to wash hands thoroughly after every diaper check and change. Spread of disease does not require ingestion of food or beverage.
I send brown bag lunches with my kids to school every day. Is there a risk of food borne illness from leaving their lunches unrefrigerated for four hours before lunchtime?
There is a risk anytime perishable food is left at room temperature for more than two hours. To reduce the risk, freeze one of the items to be included with the lunch such as a juice box or a small plastic container of water, which will keep the food cool until lunchtime. A small refreezable ice pack, like those used in coolers, is also useful.
When my family goes on a picnic I pack a cold picnic lunch, but we usually don’t eat for several hours. Are there precautions I should take to prevent food borne illness?
Pack food in a cooler with ice or ice packs. Only pack foods that have been chilled to a temperature at or below 40°F - do not use the cooler to chill room temperature foods. When finished serving cold foods, promptly return them to the cooler. If you plan to cook meat, poultry or fish on a grill while picnicking, pack carefully to prevent leakage, and take along baby wipes or moist towelettes to wash up with after handling the raw foods. A spray bottle filled with clean water and soap is another alternative - this works well for hands as well as surfaces.
My kids love to eat raw cookie dough when I bake cookies. Is this safe?
If your cookie dough contains raw eggs, there is a risk involved. To be safe, use pasteurized eggs when making cookies.
Is it safe to eat rare beef?
Cooked steaks, roasts and other cuts of beef offer a much lower risk of carrying food borne pathogens, since the bacteria exist on the outside and are destroyed in the cooking process. Ground beef is risky to eat rare because the surface bacteria are transferred to the interior of the meat during grinding, giving them a much greater surface area on which to grow. To destroy bacteria, cook ground beef to 160 °F.
http://www.ralphs.com/faqs_foodsafety.htm
