Food Poisoning and Food Spoilage >>>>>

What is Food Spoilage?

Food spoilage is caused by tiny invisible organisms called bacteria. Bacteria live everywhere we live, and most of them don't do us any harm.

What Do Bacteria Like?

As living organisms go, bacteria lead fairly simple lives. They don't walk or crawl, so the only time they go anywhere is when someone moves them. Otherwise, they pretty much stay put, content to spend their time eating and making more of themselves. Unfortunately, what they're eating is our food — especially foods that are high in protein, like meats, poultry, fish, eggs and dairy products. To be sure, some of them will go for low-protein foods like fruits and vegetables, but those ones are a lot slower. Which is why an onion or a peach left on your kitchen counter for a couple of days would still be safe to eat, while a steak clearly would not.

Spoiled Food Vs. Hazardous Food

It's important to note that spoiled food isn't necessarily dangerous food. For one thing, most people won't eat food that smells bad, looks slimy or whatever. And you can't get food poisoning from something you didn't eat. Moreover, the microorganisms that cause ordinary food spoilage aren't necessarily harmful to us. In fact, centuries before refrigerators, the earliest sauces and seasonings were used to mask the "off" tastes and smells of food that had begun to spoil. This continues to be true in parts of the world where people don't have home refrigeration units (which, interestingly enough, includes most people alive on the planet today).

Pathogens: Harmful Bacteria

The bacteria we're concerned with from a food safety standpoint are the so-called "pathogens" that cause food poisoning. And these pathogens, like salmonella or E. coli, don't produce any smells, off-tastes or changes in the food's appearance — a slimy surface, for instance, or some sort of discoloration.

Microbe Management

So how do we control these nasties? One way would be to starve them out. As noted above, bacteria need food to survive. Get rid of the food, and your bacteria problem disappears. Unfortunately, though, without food, the field of culinary arts has very little to offer. So we'll assume that food is part of the equation. Bacteria still have several other, quite specific, requirements, each of which can be controlled to some extent. Armed with this knowledge, we can effectively minimize the chances of food-borne illness. The factors we need to keep in mind include:

• Temperature
• Time
• Moisture
• pH Level (Acidity)

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The Food Temperature Danger Zone . . . ! ! ! !

 

The Food Temperature Danger Zone

It's pretty easy to avoid eating spoiled food. If the funky smell doesn't warn you off, the weird color probably will. Harmful bacteria such as salmonella and E. coli are a different story, though. When these baddies contaminate food, they do so without any physical signs, smells or tastes whatsoever. We need to rely on other methods to avoid getting sick. Like killing the little beasties — which is really not that hard to do. Temperatures hotter than 165°F kill most bacteria within a few seconds. But to do the job, it's a food's internal temperature that has to reach 165°F, not just the outside. And with the exception of poultry, cooking meats or vegetables to that degree renders them all but inedible.

Battling Bacteria

Fortunately, we have size on our side. Bacteria are really small, and it takes quite a lot of them to make us sick. So rather than killing them, and ruining our food in the process, we merely have to stop them from multiplying — or at least slow them down — so that there's never enough of them to do us any harm. We do that by controlling the food's temperature during every stage of storage and preparation.

Keep Cold Food Cold, Keep Hot Food Hot

Bacteria won't multiply in the colder temperatures of a refrigerator or freezer, or at temperatures hotter than 141°F. Where they thrive is between 41°F and 140°F, a region known as the "Food Temperature Danger Zone." To substantially reduce your chances of contracting, or passing along, a food-borne illness, make sure that your perishable foods never spend more than an hour in the Food Temperature Danger Zone. Here are some basic food handling techniques to help you do just that. And here's a table showing the key temperatures of the Food Temperature Danger Zone.

 

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Cross Contamination

Definition: Cross contamination is what happens when bacteria from one food item are transferred to another food item, often by way of unwashed cutting boards or countertops, as well as knives and other kitchen tools, or even unwashed hands. Cross contamination can in turn lead to food poisoning.

Since dangerous bacteria are killed by cooking, the risk of cross contamination is highest where bacteria from a food item that needs to be cooked contaminates a food that doesn't need to be cooked. An example of this type of cross contamination is if a cook were to cut raw chicken on a cutting board and then later slice fresh tomatoes on the same board without washing it first.

Raw eggs (which like uncooked poultry are a source of the salmonella virus) are another common cause of cross contamination.

 food safety habits such as frequent washing of hands, utensils, cutting boards and work surfaces. In professional kitchens, different colored cutting boards are used for different foods, such as raw poultry or fresh vegetables, so that cross contamination is less likely to occur.

Preventing cross contamination requires good

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Three methods of heat transfer..........

•Conduction

•Heat moving from one item to something that touching it

•Heat moving within an item

•Convection

•Heat is spread by the movement of air, steam or liquid

•Natural convection

•Mechanical convection

•Radiation

•Energy is transferred by waves from the source to the food

•Infrared cooking

•Microwave cooking

Why do we cook food? ? ?

•To make the food taste good

 

•To destroy undesirable microorganisms

 

•To make the food easy to digest

WhAt iS COOKinG ? ? ?

•Cooking is defined as the transfer of energy from a heat source to the food and alter the foods molecular structure by:

 

•Changing its texture

 

•Flavor

 

•Aroma

 

•Appearances