Acrylamide in prunes and prune juice, and how it forms
What it found
Prune products on the Canadian market contained acrylamide, and lab tests showed it can form when a plum juice mixture is dried at temperatures below 100°C.
What they found
Animal and lab studies
Formation at low heat
In lab tests, a simulated plum juice dried in an open vessel at 85°C for 24 hours made 15 µg/kg of acrylamide, and at 95°C for 24 hours made an average of 94 µg/kg.
Asparagine and sugars
No acrylamide formed when asparagine was left out or heated alone. When only asparagine and fructose were present, at 95°C for 24 hours the amount rose to 1740 µg/kg.
Wet versus dry heat
In a closed vessel at 120°C for 1 hour, the simulated juice made no acrylamide. But a real prune juice already containing 188 µg/kg increased to 375 µg/kg under the same wet conditions.
Heating real prune juice
When a real prune juice with 188 µg/kg was dried at 95°C for 24 hours, its acrylamide rose to 438 µg/kg. Adding asparagine pushed it to 684 µg/kg.
Other findings
Levels in prune products
Baby strained prunes contained 75 to 265 µg/kg, baby apple/prune juice 33 to 61 µg/kg, prune juice 186 to 916 µg/kg, and prunes 58 to 332 µg/kg.
Brand differences
Different brands varied a lot. In strained prune baby food, one brand had on average more than three times the acrylamide of another. One organic prune nectar had about 900 µg/kg.
What the authors conclude
- They conclude that acrylamide can form in foods containing asparagine if they are dehydrated for a long time even below 100°C.
- They say prune products vary considerably in acrylamide, perhaps due to recipe, processing or asparagine levels in the fruit.
- They advise that steps to minimise acrylamide formation during preparation of prunes and prune juice should be encouraged, while keeping the beneficial properties of these foods.
How it was done
Acrylamide was thought to need temperatures of about 120°C to form, but it had been found in dried fruits and prune juices. The authors wanted to measure levels in prune products and see how it forms.
They measured acrylamide in 24 baby foods and 18 other prune products bought in Canada in 2009. They also heated a simulated plum juice at 65 to 120°C for up to 24 hours, in open and closed vessels.
What it can’t tell you
- This study measured acrylamide levels in foods and in lab mixtures. It did not test what eating prunes or prune juice does to people's health.
- The lab tests used a simulated plum juice, not whole plums, so they may not exactly match what happens during commercial drying.
The paper
- Title
- Formation of acrylamide at temperatures lower than 100°C: the case of prunes and a model study
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Becalski A, Brady B, Feng S, Gauthier BR, Zhao T (2011). Formation of acrylamide at temperatures lower than 100°C: the case of prunes and a model study. Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment. doi:10.1080/19440049.2010.535217Free full textPubMed 21623495DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error