Crop Yields and Taste

That modern agriculture is incredibly productive - much more than the past - is undeniable. These USDA data, for example, suggest we produce about 170% more agricultural output now than in the late 1940s. I have argued that these these increases in agricultural productivity are signals of improved sustainability. Some people believe the the productivity improvements have been accompanied with offsetting externalities or degredations in animal welfare. A different kind of critique is that modern crops - despite being more productive - aren’t as high “quality.” For example, this piece in Politico by Helena Bottemiller Evich, titled “The great nutrient collapse” discuses evidence that vitamin content of crops has fallen as yields have increased, and there is the often-heard complaint that tomatoes don’t taste as good as they once did.

There is some biological basis for these latter concerns. If a crop breeder selects plants for higher yields, they are selecting plants that are spending their energy and nutrients into producing bigger seeds and fruits, which is energy that could have gone (in lower yielding plants) to growing leaves or roots or other compounds that affect taste and vitamin content.

I had these thoughts in the back in my mind when I came across the Midwest Vegetable Trial Report put out by researchers at Purdue and other Midwestern universities. The report compares different vegetable varieties in terms of yield and other output characteristics. I noticed for a couple vegetables - green beans and sweet corn - there were also measures of taste for each variety. Granted, these were not full-on scientific sensory evaluations and they involved small numbers of tasters, but still I thought it would be useful to test the conjecture that higher yielding varieties taste worst.

Some researchers from University of Kentucky put together the green bean report. They compared the performance of 19 different varieties of green beans. The most productive variety (named “Furano”) yielded 785 bushels over six harvests, whereas the lowest yielding variety “Slenderette” only produced 233 bu/acre in six harvests. As the image below reveals, however, there was only a weak correlation between taste and yield. The correlation was negative (-0.26), but not particularly large. About 6.6% of the variation in yield is explained by taste. The best tasting variety “Opportune“ had a taste score of 4.1 (on a 1=poor to 5=excellent scale) and a yield of 557; the worst tasting variety “Bronco” had an average taste score of 2.3 and a yield of 543. So, the best tasting bean had better yield than the worst tasting bean. Overall, the results below provide some weak support for a yield, taste trade-off.

The report also provided production and taste data on supersweet corn (this part was authored by Purdue researchers Elizabeth Maynard and Erin Bluhm). They compared 16 different types of bicolored supersweet corn (they also evaluated two varieties of white and two varieties of yellow, which I’m ignoring here). They had tasters rate “flavor” on a 1 to 5 scale. As the figure below shows, there is actually a positive correlation between flavor and yield, as measured by ton/acre. The correlation is 0.15, but the relationship is weak. The authors also report yield in a slightly different way, ears/acre, and by this measure the correlation is slightly negative (-0.09).

These results don’t necessarily negate the idea that the taste of vegetables has declined over time as higher yielding varieties have been adopted, but they do suggest that in 2017, among the particular varieties tested and among the few tasters asked, there is only a very weak correlation between taste and yield for green beans and supersweet corn.

Wizards and Prophets

I've been reading Charles Mann's latest book Wizards and Prophets, which was released earlier this year.  Overall, I've enjoyed the book.  The subtitle, "Two Remarkable Scientists and Their Dueling Visions to Shape Tomorrow's World" is an apt description for much of the content, which describes food, agricultural, and environmental problems through the lens of Norman Borlaug and William Vogt.  The history is informative, and Mann gives a fair comparison of the underlying philosophical differences, which he attributes to Borlaug and Vogt, driving much of the debate today around food, agriculture, and the environment. 

I am very much in the "Borlaug-wizard camp" (which advocates for innovation, science, research to solve food security and environmental problems) but I came away with a better appreciation for the Vogt-ian, prophet point of view (focused on resource constraints, ecological limits, need to reduce consumption, etc).  

While I thought the book was well done and well worth reading, Mann gets one aspect of this debate wrong.  Because I've seen other writers make the same mistaken point, it's worth delving into a bit.

Throughout the book, Mann refers to the Borlaug way of thinking as "top down" and the "hard way," and he contrasts this with Vogt's approach which he depicts as "bottom up", "localized", etc.  This is exactly backward. 

Mann aptly describes a core belief among the prophets: that there are finite resources on earth and just like any other species, we will grow exponentially until we exhaust our resources, and then our population and civilization will collapse. The analogy is a jar filled with few fruit flies given a fixed amount of food.  Initially, the flies have ample resources and they multiple rapidly.  However, at some point the population becomes too large for the fixed food supply, and the population collapses.  The fruit fly population follows something like an S-shaped curve over time.

Moving from flies to people, the issue is typically described in a Malthusian manner.  As the graph below shows, as we add more labor to a fixed amount of land, diminishing marginal returns kick in and the amount of food available per worker eventually falls.

If this resource-constrained view is a core belief, how do you solve the problem?  Adherents to this point of view typically urge folks to consume less or use less resource-intensive systems/products or to constrain population in some way.  But, most individuals don't want less.  Particularly folks in the developing world - they want to have and consume the things those us in the developed world enjoy, whether it be meat, air conditioning, ipads, or MRIs.  Yes, persuasion may result in a few people cutting back, but not on a scale that matches the magnitude of the problem.  Thus, the only fully effective way for the prophets to accomplish their goal (preventing catastrophic collapse) is to force or constrain the population to adopt outcomes few individuals would choose on their own.  Thus, the call for policies to mandate a cap on the number of children one can have (as occurred in China), restrictions of resource use, taxes, bans, etc. In other words, top-down planning is required to constrain growth and population, which is often manifested in "one size fits all" or highly non-localized policies.  Just recall of all the clamoring by Vogt-type adherents when Trump decided to pull out of the Paris accord that had global (i.e., non-local) prescriptions to fight climate change [note: I'm not advocating for or against the Paris accord, only noting that it is non-local and more-or-less top-down).  

The wizardly Borlaug view, by contrast, operates via entrepreneurial innovation and individual decisions of whether to adopt or not.  When Borlaug worked for the Rockefeller foundation, he/they had no "power" to force individual farms to adopt their new seeds and production practices, rather as Mann himself reveals, the early Mexican adopters took on the new seeds precisely because they saw for themselves via Borlaug's demonstration plots that they could achieve higher yields.  Yes, the types of seeds and production practices developed by Borlaug et al. spread far and wide, but it is was largely because they "worked" not because it was mandated from on high.  And, the adoption was much more adapted to local conditions than Mann lets on.  Producers in different locations ultimately used different varieties, different irrigation and fertilization techniques, etc.  As time has gone on, precision agriculture has led to even more localization of management decisions.  

The promise and hope of the Wizard is that innovation can get us off the curve shown in the graph above and move us to a new, higher outcome, as shown below. 

This isn't a denial of resource constraints, it is a recognition that innovation allows us to get more with the same or fewer or even different resources.  But, for those innovations to be adopted, they must pass the market test.  Real life-farmers and consumers need to choose to adopt them (or not). This is precisely the opposite of top-down.

Here's what I wrote a while back when Nassim Taleb referred to GMOs as a "top down" technology. 

“Taleb makes reference to the Hayek bottom-up vs. top-down planning. He says GMOs are the top-down sort. I’m not so sure. Real life farmers and people have to be willing to buy varieties that have the GMO traits. No one is forcing that outcome. It is true that competition will limit - to some extent - the diversity of plants and genetics that are observed because some plants aren’t tasty or aren’t high enough yielding. But most plant breeders keep all kinds of “ancient” varieties precisely for the purpose of trying to breed in new traits to today’s varieties (and folks working on synthetic biology are creating their own, new strands of DNA, creating new diversity). Geography also increases diversity. Iowa grows a lot of corn, Oklahoma doesn’t because it isn’t our comparative advantage. I see little reason to believe that a single GMO variety will perform well in all locations. So, yes individual companies are planning and creating new varieties, but it is all our local knowledge of what works in our places and conditions that determine whether particular genetics offered by a particular company are used. We do not have a seed czar or a DNA czar. ”

Disruptive Trends in Food and Agriculture

In the past couple weeks, I've had several opportunities to engage with some forward looking farmers and agribusiness executives, and a common theme seems to have emerged around many of the conversations: what are the issues or food and agricultural technologies on the horizon that could be potentially disruptive for the current incumbents?  

1) Block chain technology.  This isn't bitcoin, but rather the underlying technology that facilitates bitcoin trades, which could be applied to many other industries.  This Reuters article from earlier in the week, for example, indicates, "A cargo of U.S. soybeans shipped to China has become the first fully-fledged agricultural trade conducted using blockchain."  The thought is that blockchain technology might prove to be a mechanism that can more rapidly disseminate many types of information about trades (the Reuters article mentions the "sales contract, letter of credit and certificates") more widely and rapidly.  Big players like Walmart and IBM are also talking about using blockchain to improve traceability and food safety.

2) Plant-based and cellular-based protein.  This is a topic I've written about many times in the past (e.g., here or here).  What's changed is the high level of investment flowing into this space, including by companies like Tyson and Cargill.  Moreover, there are now products from companies like Impossible Foods, Beyond Meat, JUST, and others that are actually in the market.  If sales ramp up, what are the impacts on producers of current animal feeds (primarily corn and soy)?  What are the new agricultural inputs for these plant-based meat/egg/dairy alternatives? 

3) CRISPR.  Again, the basic science isn't necessarily new,  but there are new applications coming on board (non-browning apples, hornless Holsteins, etc.) and potential changes in the regulatory landscape that could accelerate (or decelerate) adoption and consumer acceptance.

4) Agricultural analytics.  This includes precision agriculture, sensing, big data, drones, modeling, etc.  Yes, these have been around for a while and there have been many discussions about data ownership and rights, but there is a sense that the data and technology have moved to a point where some adopters may be able to start gaining a competitive advantage. 

5) Online food buying.  Will Amazon do to the food supply chain what they've done in other industries?  Walmart is also making big moves into this space.  What are the implications for traceability, tracking, and vertical market coordination?

6) Trade.  Agricultural trade has a big impact on US agriculture, and it appears there may be changes in trade policy on the horizon. 

What have I missed?

Don't Want to Eat Pink Slime? Would You Even Know?

It's hard to believe it's been almost five years since the finely textured beef (aka "pink slime")  scandal broke.  To briefly re-cap, by 2012 it had become an industry standard to include finely textured beef with other beef trimmings to make ground beef.  The process enabled food processors to add value, cut down on waste, and increased the leanness of ground beef in an affordable manner.  But, a series of news stories broke, which caused public backlash against the process, and ultimately led to the closure of several plants that produced finely textured beef.  In 2013, I wrote about my visit to BPI, one of the largest producers of lean finely textured beef (this summer, ABC settled a multi-million dollar lawsuit brought by BPI regarding ABC's coverage of the issue).  I devoted a whole chapter of my 2016 book, Unnaturally Delicious, to the issue.  I'll also note, for some aspiring journalist out there,  that I can imagine a highly compelling a book-length treatment of the saga.

Back to the heart of the story, must of the public backlash presumably came about because the public was worried about taste or safety of ground beef made with finely textured beef.  In the monthly Food Demand Survey (FooDS), we've been running for almost five years, we ask about perceptions of the safety of "pink slime" and of "lean finely textured beef".  The data suggests neither are top safety concerns.  The most common answer is that people are "neither concerned nor unconcerned" about the safety of these issues (for lean finely textured beef, the average response is actually in the direction of "somewhat unconcerned").

Well, what about taste?  People may think "pink slime" tastes bad, but what would happen in a blind taste test?  Along with several of my former econ and meat science colleagues at Oklahoma State University (Molly Depue, Morgan Neilson, Gretchen Mafi, Bailey Norwood, Ranjith Ramanathan, and Deb VanOverbek), we conducted a study to find out.  The results were just published in PLoS ONE.  Here's what we found.

“Over 200 untrained subjects participated in a sensory analysis in which they tasted one ground beef sample with no finely textured beef, another with 15% finely textured beef (by weight), and another with more than 15%. Beef with 15% finely textured beef has an improved juiciness (p < 0.01) and tenderness (p < 0.01) quality. However, subjects rate the flavor-liking and overall likeability the same regardless of the finely textured beef content. Moreover, when the three beef types are consumed as part of a slider (small hamburger), subjects are indifferent to the level of finely textured beef.”

So, a burger made with 15% finely textured beef is as tasty or tastier than a burger without finely textured beef.  If people knew this, would it have changed their reaction to the Jamie Oliver show or the 2012 ABC News stories?   

Plant-based is the new local (Impossible Burger edition)

Back in 2007, Time magazine ran the following cover announcing, in essence, that local was the new organic.

Well local, has arrived and now it seems it's time to move on to something else.  Last night, I heard Randy Krotz, CEO of the US Farmers and Rachers alliance give a presentation, and as he talked he helped solidify some thoughts that have been rolling around in my head for a while. 

In short, forget local, eat "plant based."  "Plant based" appears to be the new local.  

Randy must have been prescient because, as it turns out, right after his talk, my son (who graciously agreed to attend the meeting with me) and I decided to stop for a burger, and lo-and-behold the joint offered the Impossible Burger.  This is the first time I've seen the plant-based burger - which used genetically engineered yeast to produce animal proteins - listed on a menu.  My son ordered the Impossible Burger, and I went with the good old-fashioned cow burger, which allowed a side-by-side taste test.  

Overall, I give the Impossible Burger high marks.  If we didn't know it was plant-based, I don't think we would have been the wiser.  My son thought it was quite good.  It is certainly 100% better than previous vegetarian burgers I've tried.  That said, there was just something about the beef burger that we thought tasted better - I suspect it was the animal fat.  Still, traditional animal-based protein suppliers have due cause for concern from this new competition.  That is, if these new technologies can bring down cost.  

The Impossible Burger was about a dollar more expensive (and about half the thickness) of the beef burgers on the menu, which prompted some discussion between my son and I about relative costs of animal- vs. plant-based proteins.  The ad on the table claims that the Impossible Burger uses 95% land, 97% less greenhouse gas emissions, and 74% less water than a beef burger.  If the Impossible Burger is using so many fewer resources, why is it more expensive?  Land is an enormously costly input.  Some of it may be that they are trying to recoup R&D costs or that they are exercising some price discrimination as they sell to higher income consumers.  At this point, it's hard to know, but if it is really the case that the plant-based burger uses substantially fewer resources, it should ultimately cost less than animal-based proteins.

All that is a way of pointing out that these sorts of plant-based burgers aren't a free lunch.  All those genetically engineered yeast have to "eat" something.  They require stainless steel fermentation vats, produce waste (that ironically is probably best used as feed for livestock), etc.  It will be interesting to see how cost-competitive they can become and how accepting consumers may (or may not be).