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‘Make sure consumer diets
don’t become more unhealthy
due to sustainability
concerns’
How do you make an optimal food product that is affordable, sustainable and
high quality? This question is central to the work of Dr. Peter de Jong,
Van Hall Larenstein University of Apllied Sciences. With his expertise and
experience in modeling, de Jong can calculate the ecological footprints of foods.
This has led to some surprising insights.
TEXT STEPHAN PETERS (DUTCH DAIRY ASSOCIATION, THE HAGUE) PHOTO MICHEL CAMPFENS
Can you tell us more about your
background and expertise?
“Calculating processes – or modeling – is the
common thread in my career. I started right
after finishing my degree in chemical engi-
neering. Initially, modeling aimed to reduce
costs in production processes without compromising food
quality or safety. Thirty years ago, cost control and process
safety in a factory were the most important factors in food
production. Sustainability came later. With my team, I have
brought my modeling expertise to factories and production
sites around the world. Looking at factories for these
calculations helps us stay close to the actual processes.
These days, we not only look at factory processes, but
also at the entire food chain, from farm to consumer.”
Health and sustainability have become
increasingly important in your work as process
technologist. How do you feel about this?
“For me, the extent to which a product benefits consumer
health is an important part of product quality. Take the
development of baby food. For years, companies focused
on the formulation and microbiological safety of baby
food. So what was in it. But the ingredients in a product
say nothing about the bioavailability of those ingredients
once consumed. More and more we are finding that the
bioavailability of foods is also determined by how those
foods are processed. This is of course extremely important
to our work. In our computer models, we can incorporate
all of these health aspects, including sustainability. This
allows us to design the optimal process for making a
healthy and sustainable food at relatively low costs and
minimal levels of energy intensity.”
Can you also compare foods on sustainability
indicators, like carbon footprint?
“Of course. We’re seeing, for example, that companies are
trying to dierentiate themselves on CO2 emissions per
kilogram of product. But the significance of this indicator is
very limited, because the value of a food is largely determined
by the nutrients it contains. This indicator takes no account
of this. Mineral water, for example, can have a low CO2
emissions level, but you can’t live on it. There are no or
hardly any nutrients in it. That’s why there’s no point to
comparing the CO2 emissions per kilogram of a soft drink
to that of milk. Or of bananas to meat.”
In reality, though, foods are being compared to
each other based on CO2 emissions per kilogram
of product. Why is that, and why is this wrong?
“We’ve only been looking at the ecological eects of our
food for about 15 years. This forms the basis for LCA
(life-cycle assessment) calculations of foods. The LCA
methodology can calculate the sustainability indicators of
Interview
1
This article was published in Dutch in Voeding Magazine 2
|
2021
Interview
food production, such as CO2 emissions, land use or water
use. Based on LCAs, a sum can be made of the so-called
CO2 footprint of a product in all phases of the production
chain. This results in the ecological footprint, which is
expressed in terms of CO2 emissions per kilogram of
product. From this – generally speaking, because there
are multiple exceptions – it appears that animal products
have a higher CO2 footprint than products made from
plants. As a result, it is often assumed that a diet with
fewer products from animals and more products from
plants means a lower CO2 footprint, which is good for
the planet. This could be true for a specific type of diet.
But you simply cannot compare products like this. I’ve
mentioned the example of soft drinks and milk. If you
want to compare products on their sustainability, then
you also have to account for quality and health eects.
This is not happening enough right now. And there’s
another complication here: not all of the LCA calculations
are of the same quality. There are many intrinsic assumptions
that are dicult to trace back.”
Dr. Peter de Jong
1983-1987 Graduated in Chemical
Engineering, The Hague University of
Applied Sciences
1987 - present Principle Scientist Food
Processing, NIZO Food Research, Ede
1996 PhD in interaction between protein
denaturation and equipment contamination,
TU Delft
2012 - present Program Director, Institute
for Sustainable Process Technology
2014 - present Lecturer in dairy process
technology, Hogeschool Van Hall Larenstein,
Leeuwarden
‘There’s no point to
comparing the CO
2
emissions per
kilogram of a soft
drink to that of milk’
2
Interview Dr. Peter de Jong
Why are there such differences in the quality
of LCAs?
“The discussions around the sustainability aspects of
food started with CO2 emissions. Later, other aspects were
added, such as land use and the emission of phosphate and
nitrogen. Notably, the issue has been oversimplified by the
media. We see ‘plant proteins are great’ and ‘animal proteins:
time to get rid of them’. When I hear these things, I think:
let’s do the math. What data was used and what assumptions
were made? When you dig into the LCA data, several
things stand out. If you look at dairy products, you see
that the dairy chain has closely mapped out the impact
of dairy production from beginning to end. Accurate LCA
calculations can be made with this data. But such detailed
LCA reports don’t exist for dairy substitutes, or are not as
readily available. Secondly, we often only see the positive
aspects of plant-based alternatives in the media and popular
science articles. And because we lack good LCA reports on
these plant-based alternatives, we are left with Google. For
the CO2 footprints of say oat drink, Google will take you to
the websites of environmental organizations and vegetarian
or vegan food producers. In their messaging, they are
always going to use favorable data on plant products and
negative data on animal products. On the internet, you’ll
find LCA data on plant products compared to absurdly high
CO2 values for milk products. Such high numbers may
come out of regions like Africa, but not from Europe or the
United States which have the most ecient dairy production
sectors. That could make a two or three-factor dierence!
Not to mention that the situation in Africa is entirely
dierent. The LCA values are higher there than in Europe,
but the dairy chain in Africa is set up in such a dierent
way, and there are other interests that come into play.
There, a cow supplies milk, but also functions as a tractor
and it can be a financial buer if needed.”
You say that LCAs are used in the wrong
way. Why aren’t LCAs enough for comparing
products?
LCA results are usually expressed in terms of CO2 emissions
per kilogram of product. This is fine if you want to make
production chains more ecient, for example. It will show
you if the measures you have taken have had an eect on
CO2 emissions. But for years, CO2 emissions per kilogram
of product have become a kind of basis for comparing foods
to each other. That soft drinks or broccoli have a lower CO2
footprint than respectively semi-skimmed milk or eggs does
not mean that you should replace milk with soft drinks or
eggs with broccoli. Policy is being made right now based
on the LCA per kilogram comparison. But the discussion
around fewer animal products and more plant-based diets
requires nuance. You can’t look at just food footprint.
If you want to make diets more ecologically friendly, then
you should do this in a healthy way. There’s no scarcity of
kilograms of calories in the world, but we don’t have
enough nutrients like proteins. This is also true in the
NRF15
NRF11
NRF9
0
20
40
60
80
100
120
140
160
180
Whole milk Soy drink Oat drink Pea drink
Nutrient Rich Food index
Whole milk Soy drink Pea drinkOat drinkAlmond drink
Carbon footprint (kg CO2-eq/kg product)
0,0
0,2
0,4
0,6
0,8
1,0
1,2
1,4
NRF15
NRF11
NRF9
0
20
40
60
80
100
120
140
160
180
Whole milk Soy drink Oat drink Pea drink
Nutrient Rich Food index
Whole milk Soy drink Pea drinkOat drinkAlmond drink
Carbon footprint (kg CO2-eq/kg product)
0,0
0,2
0,4
0,6
0,8
1,0
1,2
1,4
Figure 3. CO2 emissions of foods in relation to Nutrient Rich Food scores
Figure 2. Nutrient density (Nutrient Rich Food index score) of various foods
NRF9: protein, fiber, vitamin A, C and E, calcium, iron, magnesium, potassium NRF11: protein,
fiber, vitamin A, B12, C and E, calcium, iron, magnesium, potassium, zinc NRF15: protein, fiber,
vitamin A, B1, B2, B12, C, D and E, calcium, iron, magnesium, potassium, zinc, unsaturated fats,
folic acid.
Figure 1. CO2 footprint per kg product of various foods
kgCO2 eq/NRG15
kgCO2 eq/NRG11
kgCO2 eq/NRG9
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
4,0
Whole milk Soy drink Oat drink Pea drink
CO2-eq per kg/NRF index
3
Dutch context. In the west, we tend to eat too much
protein, but vulnerable populations like the elderly don’t
get enough. The protein problem is even more pronounced
in the global context. UN data indicates that every year,
we need to produce 3 million more tons of protein in
order to meet the global need. In making our diets more
sustainable, it should be about the quality of our food, not
the quantity. This is why we should find another indicator
besides CO2 emissions per kilogram of product to express
the ecological footprint of foods. This indicator should
account for a food’s nutrients and health benefits. This is
the only way to gain better insight into which foods or
combinations can be substituted for a more sustainable diet.”
Which indicators should we use to determine
our footprint?
“Lots of indicators can be used. I am currently working
on a scientific paper on it. Comparisons based on a single
nutrient like protein are too limited. You can’t base a
healthy diet on protein alone. We need a combination of
many dierent nutrients to stay healthy. By quantifying
the most important nutrients in a product, you can attain a
new ecological footprint. The so-called Nutrient Rich Food
(NRF) scores are one example. A product’s contribution to
the daily requirements of the consumer can be calculated
based on a summation of the nutritional benefits of that
product. Products with a high NRF score have a lot of
added value for our health. This also means that for
products with low NRF scores, we have to eat more of
them, which often means more unwanted calories and a
higher footprint. By using the NRF scores in the ecological
footprint of foods, you can connect ecological footprint to
a product’s health benefits. This sometimes provides a
dierent picture than you would expect from the ecological
footprint per kilogram.”
“The rationale here is maybe best illustrated in figures 1,
2 and 3. Figure 1 is the ‘old’ way of comparing products
based on CO2 per kilogram of product. You see that compa-
red to plant-based drinks, milk has a higher CO2 footprint.
This perspective changes when you account for a food’s
nutritional value and thus its health benefits. Figures 2 and 3
show the NRF scores for milk and plant-based substitutes.
When you combine the ecological footprint with the NRF
scores, these plant-based substitutes show a less positive
picture. Of course there are many nuances here, but this
makes clear that nutritional value and (micro)nutrients
have to be included when comparing products in terms
of sustainability.”
The world of food is under considerable pressure
right now, and concrete plans are being made
to combat climate change. What’s your view
on this?
“There are more and more publications in scientific literature
that do look at the number of nutrients in a food and their
digestibility. This is a positive development, because a
nutrient’s digestibility is an important factor. Plant proteins
are often less digestible than milk proteins. So you have
to consume more to reach the same levels in your body.
This of course has consequences for the footprint. Another
concern in the research continues to be the LCA data.
Ideally, a research team would conduct LCAs of all relevant
products using the same method and at the same level of
detail. This way we would have LCAs of the same quality.
Thankfully someone has made a start here. Blonk Consul-
tants in the Netherlands is doing good work in this area.
But it is a labor-intensive task. I hope that politicians and
policymakers will be aware of these complexities before
aectuating policies towards plant-based alternatives on
false grounds. Because when it comes to sustainability
policies for our food, the health of the consumer must be
guaranteed. This means that we have to stop using the
indicator ‘per kilogram of product’ for the ecological
footprint, and replace it with an indicator that accounts
for a food’s nutritional value and health benefits. This way,
you make sure that consumer diets don’t become more
unhealthy due to sustainability concerns, even though
the intentions are good.”
Some grocery stores are thinking about working
with eco scores, which would mean including
the CO2 emissions per kilogram on food
packaging. What do you think of this?
“This would be unwanted at this moment. Product
labels should provide good information to consumers.
Not confuse or mislead them. Food labels already include
a lot of information. You may wonder to what extent even
more information would help the consumer. And if you
want to provide an eco score, then you should always do
this in relation to the nutrients in the product. In fact,
that’s the main reason why a consumer buys a food: in
terms of how much it benefits their health. Only the
second question would be: has it been sustainably
produced? In that order.”
‘When it comes to sustainability,
nutritional value and the
nutrients themselves must be
included in product
comparisons!’
4