CABI Blog

A few weeks ago we were discussing beer – or rather the lack of it expected
as a result of climate change. This week, Chalmers
University of Technology in Sweden has unveiled a new superfood. Even less
appealing than no beer, this rather unappetising dish is the Swedish equivalent
of tempeh and was brewed up as part of a Ph.D. research project.

As the student responsible, Charlotte Eklund-Jonsson, explains, the main
objectives behind her work were to develop a whole grain product that did not
lose its available iron content. Normally with barley, you can have whole grain
or high iron availability. Fermenting it with the micro-fungus Rhizopus
oligosporus* (something my colleagues at CABI
know a lot about), she has managed to preserve all the benefits of a high
fibre-whole grain, high folate food, while doubling the availability of the iron
it contains. Eklund Jonsson points out that while it was designed as a highly
nutritious foodstuff for vegetarians, the fact that it is produced from barley
or oats – locally produced in Sweden; might also make it an attractive choice
for consumers of the ‘green’ persuasion.

But seriously – however much responsibility we are willing to accept for
using up all the oil, do we really deserve this?

We might have no choice. This week, World Environment Day coincided
with the start of the UN’s
food crisis summit – a call to action on the rising cost of food, its
consequences and how to minimise its impact in the face of the rapid rise in
demand for biofuel feedstocks. If you’re quick, the UN are webcasting
the event live. If you’ve missed it, you can still get a grip of the issues:
Handpicked… blogger Christina discussed the
price of a week’s shopping at the end of April and the World Food Programme
has tackled the issue head-on in a series of concise and informative short
films. I recommend Who Pays for
the Cost of Hunger?¹, a four minute film that explains the major issues
and puts our European concerns into stark perspective. Maybe tempeh sandwiches
aren’t such a bad idea – some 70 million people are living off less.

Sandwiched between World Environment Day and the UN’s high level discussion,
Eklund-Jonsson will defend her Ph.D. on Thursday. While I wish her the best of
luck – she has, after all been instrumental in developing of a foodstuff that is
highly nutritious, is made from locally grown ingredients (until climate change
means the Swedes can start fermenting home-grown grapes in large, tasty,
quantities instead); I sincerely hope that this isn’t a taste of the future.

¹Download wfp177361.wmv

*Investigating the use of Rhizopus fungi to produce tempeh, (a very
simple search, for those of you familiar with CAB Abstracts: I started with ‘(Rhizopus):od
AND (tempe OR tempeh)‘), unearthed a whole host of different things are used
around the world to make tempeh. Nigerian scientists have found vegetable
peelings make a reasonable substrate for the fungus²; while elsewhere in Africa,
the yambean seems quite popular³. Polish food technologists have been working
with grass pea (Lathyrus sativus)⁴. Ekberg-Jonsson⁵ collaborated with her
neighbours at the Swedish University of Agricultural Science, who have also been
experimenting with barley tempeh^6,7, so who knows, it might become a staple of
the Swedish diet in years to come.

²Aderibigbe, E. Y. and  Kolade, K. B. (2003) Propagation of tempeh Rhizopus
oligosporus. I: Use of organic food wastes. Nigerian Journal of Biotechnology
Vol. 14(1), pp. 78-84
³ Azeke, M. A. , Fretzdorff, B. , Buening-Pfaue, H. and Betsche, T. (2007).
Comparative effect of boiling and solid substrate fermentation using the tempeh
fungus (Rhizopus oligosporus) on the flatulence potential of African
yambean (Sphenostylisstenocarpa L.) seeds. Food Chemistry Vol.
103(4), pp. 1420-1425
⁴Starzynska-Janiszewska, A. , Stodolak, B. and Jamróz, M. (2008). Antioxidant
properties of extracts from fermented and cooked seeds of Polish cultivars of
Lathyrus sativus. Food Chemistry Vol. 109(2), pp. 285-292.
⁵ Feng XinMei , Passoth, V. , Eklund-Jonsson, C. , Alminger, M. L. and Schnürer,
J. (2007). Rhizopus oligosporus and yeast co-cultivation during barley
tempeh fermentation – nutritional impact and real-time PCR quantification of
fungal growth dynamics. Food Microbiology Vol. 24(4) pp. 393-402.
⁶Feng, X. M. , Olsson, J. , Swanberg, M. , Schnürer, J. and Rönnow, D. (2007).
Image analysis for monitoring the barley tempeh fermentation process. Journal
of Applied Microbiology Vol. 103(4), pp. 1113-1121
⁷Feng XinMei , Larsen, T. O. and Schnürer, J. (2007). Production of volatile
compounds by Rhizopus oligosporus during soybean and barley tempeh
fermentation. International Journal of Food Microbiology Vol. 113(2) pp.
133-141