MCC BIO235 Unit 2 Discussion Latest 2021 October

BIO235 Introduction to Microbiology

Unit 2 Discussion

Safe Food Supply

The recent outbreak of E. coli O157:H7 found on fresh spinach leaves is a concern for our society.  More than 180 people in 23 states have become sick, and several have died so far.

             Needless to say, our food is considerably safer to eat today than it was hundreds of years ago.  For example, in medieval times human sewage/waste water supplies were created near natural water sources.  Microbes and contaminants would thus pollute the water source and cause disease.  Obviously, drinking water from underground springs – which was away from the human waste contaminated water sources – did not cause disease, and thus was attributed “medicinal” powers.  (This notion - that bottled water from natural springs is healthier for us – is still around even today!)  In modern times water supply locations are carefully planned and are constantly monitored so that contaminant levels are kept at safe government mandated levels.

            Concerning the spinach crisis, we have failed to listen to years of human history – that cooking food will prevent us from dying from it.   A few decades ago canned and frozen foods (which need to be cooked) were the latest and greatest, emphasizing convenience, long storage life and low cost.  Today’s trends, however, are fresh, unprocessed, and bagged so that they are ready to eat for quick, nutritious and easy meals.  Examples are the salads and vegetables in a bag which are common in every food store.  Bagged salads assume that the vegetables are healthier because they are “fresh” and minimally processed, and it gives the consumer an illusion of safety.  But the vegetables are not sterile, not pasteurized, and exposed to light and air which promote bacterial growth.  The vegetables are subjected to chlorinated cleaning which is good for removing the microbes and dirt on the surface, but microbes can enter the leaves through the cut / break or the leaf from the stalk and live inside the leaves for 6 months or longer.  Chlorination and general washing cannot remove the internal bacteria.  While it takes 100 million cholera (Vibrio cholerae) bacteria to cause their infection, it only takes 10 – 100 E.coli O157:H7 cells to cause illness.  And it only takes one bacteria contaminated leaf to spread and contaminate every leaf in the bag. 

      Cooking the spinach will kill the bacteria, and the canning process also uses very high heat that guarantees bacterial death.   But what about the loss of nutrients resulting from the heating process?  Contrary to some reports, cooking vegetables does not necessarily make the vegetables less nutritious.  While cooking spinach does reduce vitamin C content, the loss is made up by the fact that most Americans already get enough vitamin C from other food sources.  Moreover, spinach’s claim to fame is that it is a good source of iron.  However, cooking releases more iron from the spinach leaves, thus a person will get more iron from cooked spinach than from fresh!

So what does this all signify? How are we going to keep the US food supply safe from E. coli and other microbes? Do we ban bagged vegetables, or not allow fresh vegetables at all? Do we improve the quality control in the food processing plants? If we do, that will cost a great amount of $$ to implement, and consequently will significantly raise the cost of food. As a result, the extreme increase in production costs will drive the smaller companies and local farmers out of business. Does the government have the right to impose such controls? Can we sue the food company that unknowingly sold the contaminated spinach?  Should we have disclaimers in the market saying – “Eat raw carrots at your own risk”?  And what are you going to do at your next party when you come to the fresh veggie platter and dip?!?