Why Does Food Spoil?
Food 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.
Bacteria: 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 line – When 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 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.
Exclusion and Restrictions: Understanding Employee Health and the Food Code
I received a call earlier in the month from a foodservice operator who suspected that one of their employees may have fallen ill and wondered if they had to send the employee home for the day. Once I started to ask a few more questions, it became obvious that the operator wasn’t really in-tune with the food code requirements on restrictions or exclusions for employees who may not be feeling well. Given that most operations are dealing with staff shortages currently and the fact that we are about to head into the fall and winter – when we tend to see an increase in upper respiratory and other illnesses, such as the flu - it seemed like a very timely and important topic for the blog this month.
Cross Contamination and the Surfaces that go Unnoticed
In October, I ran across a new research study published in the Journal of Food Protection in early-September. The article explored cross contamination in consumer kitchens during meal preparation. One of the authors was a previous SafeBites presenter, Dr. Ellen Shumaker, at North Carolina State University. Although the setting was consumer kitchens and not the commercial kitchen many of you deal with daily, the findings were very applicable to what we often see in the foodservice setting.
Emergency Preparedness: The Not-so Calm After the Storm
If you and your foodservice operation have been hit by an emergency or other disaster, what comes next and how do you move forward? Much of the answer to this is predicated on the actual disaster that you are dealing with – a flood is certainly a much different than a fire, but some of the food safety considerations remain the same if your business has been left intact and has not been damaged by the disaster.
Emergency Preparedness and Responding to a Disaster with Food Safety in Mind
As I write the first blog this month, the realities of the devastation in Florida are coming to light as we also deal with the aftermath of Hurricane Fiona, which impacted Puerto Rico late in September. Recent news has been focused on the recovery efforts for all who have been impacted. Thus, I thought it would be fitting this month to discuss emergency disaster planning resources in our first blog and delve into recovering from a disaster in our second blog later this month.
