How the discovery of a century-old fruit cake triggered a question about today's use of chemical preservatives
Director Michael Holsapple discusses a 106-year-old fruitcake and how it relates to today's modern food industry.
August 22, 2017 - Author: Michael Holsapple
Michael Holsapple is Director of the Michigan State University (MSU) Center for Research on Ingredient Safety (CRIS) and Professor in the Department of Food Science and Human Nutrition. He is also a toxicologist with over 35 years of experience.
I was asked to consider a recent article entitled, ‘Almost Edible’ 106-Year-Old Fruitcake Found in Antarctica, with an interesting twist. Specifically, I was asked to provide some perspective on what this discovery could mean to today’s food industry – e.g., here’s an item that withstood the test of time without modern preservatives, so there must be some things that food companies could learn from this discovery.
In the interest of transparency, I have to disclose that I have never been a big fan of fruit cake. I attended St. Mary’s Elementary School, and was taught mostly by nuns, who were (apparently) big fans of fruit cake. They would frequently give out large pieces of fruit cake for winning a spelling bee, or an arithmetic quiz. My disdain for fruit cake was sometimes so strong, that I would occasionally misspell a word, or give the wrong answer to a math problem – on purpose – just to avoid the prospect of receiving a piece of fruit cake.
That context is important because the picture of the century-old fruit cake didn’t look any different from what I remembered about the fruit cakes of my youth. The article described this antique culinary delight as “well preserved”, and noted that it “looked and smelled edible”. Most importantly, the article underscored that “there is no doubt that the extreme cold in Antarctica has assisted its preservation”. My analysis probably could have ended there, because, I am confident that food companies are well aware that storing foods in a refrigerator or a freezer can extend their ‘life’.
But, I decided to go a little further and found an article entitled, Food Storage – How Long Can You Keep Fruit Cake. This link from Still Tasty (Your Ultimate Shelf Life Guide) notes that, if a few precautions are taken, fruit cake can be stored for “1 month at normal room temperature” and for “6 months in the fridge”. Regarding freezing fruit cake, it is emphasized that fruit cake “will maintain best quality for about 12 months; but will remain safe beyond that time”. Still Tasty emphasizes that their “food storage information is drawn from multiple sources”, and includes “research conducted by US government agencies, including the USDA, the FDA, and the CDC”. Perhaps most relevant to the purposes of this story, Still Tasty emphasized that “the freezer time shown is for best quality only – fruit cake that has been kept constantly frozen at 0 degrees F will keep it safe indefinitely”. So, from my perspective, the discovery of a 106-year old fruit cake in Antarctica provides no insights about the use of modern preservatives.
Moreover, as noted above, the article was entitled, ‘Almost Edible’. It was also emphasized in the article that “there was a very, very slight rancid butter smell to it”. I was struck by the fact that neither of these points would compel anyone to sample this fruit cake, which made me wonder about the claim that it was “well preserved” – the apparent ‘driver’ for questions about modern preservatives. However, the reference to a “rancid smell” also made me want to know what that ‘clue’ could tell us about this fruit cake.
I discovered that rancidity is a term generally used to denote unpleasant odors and flavors in foods resulting from oils or fats being oxidized. In that regard, it is important to note that some chemical preservatives added to foods are anti-oxidants. Interestingly, appearance of a food item – e.g., color or texture – is not normally changed due to this deteriorative process, which would explain why the article noted that the 106-year fruit cake “looked edible”. Besides the smell, is there anything wrong with eating rancid oils? That question was addressed in a 2012 article, What's that smell? Rancid food is a waste, and potential danger. Apparently, there are at least two things wrong with eating rancid oils. First, foods contaminated with rancid oils “lose their vitamins”, and second, rancid oils “can also develop potentially toxic compounds”. The bottom line is that the “rancid smell” associated with the 106-year old fruit cake should be a warning against consuming it.
The last article also highlights a relatively recent trend that underscores the possibilities for unanticipated consequences associated with changing food product formulations. Specifically, the problem with foods going rancid has been compounded as a “byproduct of Americans and food manufacturers swapping trans fats for polyunsaturates in their products during the past 10 years”. This trend “resulted in a whopping 58% percent drop in trans-fatty acid consumption in the US in the past decade"; but the article emphasizes, “for all of their artery blocking evil, trans fats had at least one big benefit – they were very stable, meaning that they took forever to go rancid. When these fats were replaced with polyunsaturates, such as corn and soybean oil, that shelf stability collapsed Experts advise paying close attention to ‘use by’ and ‘sell by’ dates on packages, which may have changed in recent years because of new formulations”. Of course, while it is hard to argue with the decision to ‘call for’ a reduction in our consumption of trans fats; who would have predicted the dramatic reduction in the ‘shelf life’ of products?
That last observation made me reconsider the “interesting twist” that framed the original query about what could be learned by the discovery of a 106-year old fruit cake – e.g., effectively, a ‘call for’ a reduction in the use of modern preservatives. In that regard, it is important to note one of the conclusions reached in a 2015 publication by Petrun et al., Shaping health perceptions: Communicating effectively about chemicals in food – “30% of consumers are cautious about serving foods with preservatives”. I want to end this story by considering the possibility that reducing the use of modern preservatives may have unanticipated consequences. By way of background, the Center for Food Safety (CFS) was established on the campus of the University of Georgia in April, 1993 with a mission of maintaining and improving the safety of foods through the development of methods that detect, control, or eliminate pathogenic micoorganisms or their toxins. Prof. Mike Doyle, the founding Director of the CFS, was a co-author on a review published in February, 2017 in the Annual Reviews of Food Science and Technology, The Challenges of Eliminating or Substituting Antimicrobial Preservatives in Foods. This review “addresses the safety of antimicrobials and the potential consequences of removing those that are chemically synthesized or replacing them from so-called natural sources”. Most importantly, the bottom-line conclusion from this review was that “Such changes can affect the microbiological safety and spoilage of food, as well as reduce shelf life, increase wastage, and increase the occurrence of foodborne illnesses”.
Consumers should expect their food supply to be safe. Decisions to remove preservatives from foods should be based on a cost-to-benefit analysis that considers the best science. Is the science on the safe use of chemical preservatives consistent with their removal and replacement with natural alternatives – e.g., a benefit in the context of giving consumers what they think they want – but, which can occur at the cost of unanticipated consequences, including an increase in the occurrence of foodborne illnesses?