How can I keep fruit & veg fresh for longer?
From fermentation to deep freezing, we investigate the science that can help us keep food for longer and hear about preservatives that could upset our gut flora and fauna.
As many of us gear up for the annual Christmas feast, some of you may be wondering how to eat everything before it goes off. It’s a great question, as the UN puts global food waste at a whopping 1.3 billion tonnes a year – that’s one third of all edible produce being thrown in the bin.
So this week the team investigates listener Peter’s query about what makes some fruit and vegetables rot faster than others. Preserving food used to be about ensuring nomadic populations could keep moving without going hungry, but these days some things seem to have an almost indefinite shelf-life. Is it about better packaging or can clever chemistry help products stay better for longer? A Master Food Preserver explains how heat and cold help keep microbes at bay, and how fermentation encourages the growth of healthy bacteria which crowd out the ones that make us ill.
Presenter Datshiane Navanayagam learns how to make a sauerkraut that could keep for weeks, and investigates the gases that food giants use to keep fruit and veg field-fresh. But as the industry searches for new techniques to stretch shelf-life even further could preservatives in food be affecting our microbiome? Research shows sulphites may be killing off ‘friendly’ gut bacteria linked to preventing conditions including cancer and Crohn’s disease.
Produced by Marijke Peters for BBC World Service.
Featuring:
Christina Ward, Master Food Preserver
Dr Heidy den Besten, Food Microbiologist, Wageningen University
Ian Shuttlewood, Tilbury Cold Store
Professor Sally Irwin, University of Hawaii
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Added sulphites might be damaging our gut microbiome
Duration: 02:00
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- Fri 17 Dec 202120:32GMTBBC World Service Online, Americas and the Caribbean, UK DAB/Freeview & Europe and the Middle East only
- Fri 17 Dec 202121:32GMTBBC World Service Australasia, South Asia, News Internet & East Asia only
- Sat 18 Dec 202102:32GMTBBC World Service Europe and the Middle East
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- Mon 20 Dec 202102:32GMTBBC World Service
- Mon 20 Dec 202105:32GMTBBC World Service Americas and the Caribbean
- Mon 20 Dec 202109:32GMTBBC World Service
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