Why Does Food Spoil?

bagsFood gradually deteriorates because of a natural process of aging, just like humans. However with all foods, there are a few things we can do that have a positive effect on the shelf life and safety of our foods at the restaurant. Some preservation is done at the food manufacturing plant, some naturally, but a better understanding of the processes may help you extend that shelf life. Preservation methods and storage conditions must be designed to reduce the rate of decomposition and protect the safety, appearance and taste of our food.

The causes of food spoilage – Plant and animal tissue starts to decay soon after raw food has been harvested or killed. The spoilage process is usually caused by microorganisms such as fungi (molds & yeasts), spoilage bacteria, and their enzymes. Not all these changes in food are undesirable.  Some people like aged beef and cheeses or very ripe fruit. The production of wine and beer involves conversion of sugars to alcohol, while souring of milk is essential in the production of cheese.

However, it’s important to remember that some of the conditions that accelerate spoilage, such as inappropriate temperature and moisture control, also encourage the growth of pathogenic microorganisms that cause foodborne illness. Consequently, spoiled food is not just an issue of quality, it is also often a question of food safety.

Mold & Yeast:  Corn, nuts, breads, meat, cheeses, fruits and vegetables are affected by mold. With  most cheeses (i.e. cheddar, mozzarella, American, or Swiss), don’t try to salvage cheese that shows visible mold by cutting it away unless it’s a natural part of the cheese like bleu cheese, Brie, or Camembert.  Mold forms a network of microscopic strands that extend into the foods which could cause allergic reactions or illness, so discard them. Most cheeses don’t improve with age. Deli meats are the same. Yeast can cause discoloration, slime, and odors on sweet, acidic refrigerated foods or jams/jellies.

bags 2Bacteria:  Some spoilage bacteria are also pathogenic (disease causing). For example, Clostridium perfringens (a common cause of spoilage in meat & poultry) and Bacillus cereus (spoils milk & cream) are also responsible for causing foodborne disease. Most foods are subject to bacterial growth.

Enzymes:  They are naturally present in the cells of microorganisms that break down animal and plant foods. Breakdown continues until the enzymes are inactivated by blanching or cooking.

Other causes of spoilage include: 1) bruising or piercing because of rough handling such as vegetables, fruits or vacuum packaged food; 2) oxidation (changes the taste or texture when exposed to oxygen) or freezer burn; 3) pest infestation because of poor receiving control, storage, rotation or cleaning; 4) adulteration by addition of leftover food to fresh food, inferior or undesirable food or ingredients.

Detecting spoilage includes the typical indicators such as appearance (discoloration or slime), texture, smell or taste (obviously not recommended if any of the others are present).

Bottom lineWhen in doubt, throw it out. Food spoilage does affect your bottom line in food waste dollars, so prevention includes good receiving inspection practices, following manufacturer’s instructions, utilizing innovative active packaging or food storage bags, unfailing temperature recording and control, being observant and certainly good sanitation and personal hygiene by food handlers. 

 

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About the Author: Lacie Thrall

Lacie Thrall PictureLacie Thrall passed away in early 2017 after a long illness. She dedicated her 35-year career to improving the health and well-being of others by promoting food safety best practices. Lacie worked in environmental health for 17 years before joining FoodHandler in 1997 as the Director of Safety Management. While at FoodHandler, she trained employees and customers on safe food handling practices, including proper hand hygiene and glove use. Later as a FoodHandler consultant, Lacie provided the foodservice industry with food safety information and advice through her blog on FoodHandler.com.

Handling Leafy Green Salad

We have had several produce outbreaks of foodborne disease from our lettuce, spinach, and other greens in the last several years that have been devastating to the produce growers and distributors, retail grocery stores, restaurants, and consumers.

Food Packaging Safety in a Vacuum

Extending the shelf life of fresh foods has come a long way in the food industry since curing meats with salt and sugar or canning vegetables with heat processing. The food service and consumer markets needed some better visual packages to draw the eye to the freshness factor and the technology of food packaging has filled our dinner plate. Vacuum packaging and modified atmosphere packaging, shortened to “MAP”, are the terms used for the method of food packaging used every time we choose convenience over more complex scratch meal preparation. According to industry statistics, billions of packages of vacuum and MAP-packaged foods flood the marketplace today. In both modified-atmosphere and vacuum packaging, food is packaged in a pouch made of barrier film.

The Eleven Commandments of Food Safety at Your Restaurant

Lists help us remember all kinds of information. Given the list of recent national foodborne outbreaks in the news, keep repeating this list to your food service team. They are kind of like “commandments”. As a professional in a food service facility we should think of the very basic food safety concepts that every crew member should aspire to learn, even though this list may have different priorities based on your menu. The first 3 apply to anyone who serves food, from a bag of popcorn to a full course meal. As chefs or managers, if we can “set the example” by repeating good food safety practices visibly to the crew, it will help them understand how important it is to the success of your facility. Thou shalt:

The Worst Customer Complaint: Foodborne Illness

Food service managers and crew try to follow the rules of food protection.  Yet, occasionally a complaint may arise and these calls take priority over all other daily crises.  If you have been in the food service industry long enough, you may have gotten one of these.  A customer may claim, "I think your food made me ill." These words inflict instant anxiety. If it happens, here are some next steps to think about in advance of such a claim: