Jet-Puffed color changing marshmallows are an interesting new product that is available on the shelves of grocery stores through the end of September.1 The color of these marshmallows changes when exposed to heat: the blue version turns green, while the pink version turns orange. Representatives at Jet-Puffed report that a “secret color changing ingredient” is used that is responsible for the color changing effect.1 Naturally, we all want to know that this secret ingredient is! So I went to work in the lab to see if I could figure anything out. You can see the results of my investigations in Video 1.2
Video 1: Color Changing Marshmallows?!, Tommy Technetium
There’s more evidence that points to microencapsulated curcumin being responsible for the color changes observed. For example, “oleoresin turmeric” is listed in the ingredients of these marshmallows,3 and turmeric contains curcumin.4 Further, several studies exist that describe the properties of turmeric microencapsulated in gelatin and starch,5-6 both of which are also found in the ingredients list in these marshmallows! Interestingly, the pigments in microencapsulated turmeric particles are reported to be known to be affected by many factors…including heat! So it’s not too far a stretch to propose that curcumin is microencapsulated in the gelatin and starch contained in the marshmallows, and that heat somehow causes the curcumin to display its color.
I did other experiments in addition to those reported in the video to further test the yellow residue for the presence of curcumin. First, I illuminated the yellow residue with UV light. Upon doing so I saw bright yellow emission, consistent with the fact that curcumin fluoresces yellow under UV light.4 Curiously, the marshmallows themselves did not fluoresce when illuminated with UV light (data not shown).
Figure 1: Yellow residue on filter paper collected via filtration of blue color changing marshmallow extract. Left, under room lights; right, under UV illumination.
I also added dilute solutions of sodium hydroxide and sodium borate to the residue. Addition of sodium hydroxide caused a color shift to orange (Figure 2, spot on left), while sodium borate caused a color shift to red (Figure 2, spot on right). These observations are consistent with the known color changes of curcumin at higher pH, and the fact that curcumin binds with borate ion to form a rose-red complex called rosocyanine.4
Figure 2: Yellow residue on filter paper collected via filtration of red color changing marshmallow extract. The spot on the left is from added NaOH solution and the spot on the right is from added sodium borate solution.
I think experimenting with these marshmallows could provide a very interesting platform for students to explore a variety of chemical topics such as fluorescence, acid-base indicators, filtration, and thermochromism. I can envision a lot of interesting in-class activities and outreach activities! However, if you do wish to use these marshmallows in your classroom you might want to stock up on them: for now Jet-Puffed is reporting that they will only be selling them for a limited time.1 Be sure to let me know your thoughts about how you might use this product and what chemical topics you might discuss when doing so. I’d also like to hear any thoughts folks have on my interpretation of what I think is going on during the color changing process.
Happy Experimenting!
Acknowledgement: Thanks to Karen Sorenson who first told me about this interesting new product!
References:
- https://www.today.com/food/groceries/jet-puffed-color-changing-marshmallows-rcna81862 (accessed 7/18/23)
- Tommy Technetium YouTube Channel, Color Changing Marshmallows?! (accessed 7/18/23)
- Jet-Puffed Color Changers Marshmallows 12oz Bag available on Amazon: https://www.amazon.com/Jet-Puffed-Color-Changers-Marshmallows-12oz/dp/B0BR8H4S6P
- Tom Kuntzleman, Investigations of Chemicals in Natural Food Coloring. Part 3: Sunflower, ChemEd X, 2017.
- Cano-Higuita, D.M., Malacrida, C.R. and Telis, V.R.N. J Food Process Eng, 2015, 39, 2049-2060.
- Zuanon, L.A.C., Malacrida, C.R. and Telis, V.R.N. J Food Process Eng, 2013, 36: 364-373.
NGSS
Planning and carrying out investigations in 9-12 builds on K-8 experiences and progresses to include investigations that provide evidence for and test conceptual, mathematical, physical, and empirical models.
Planning and carrying out investigations in 9-12 builds on K-8 experiences and progresses to include investigations that provide evidence for and test conceptual, mathematical, physical, and empirical models. Plan and conduct an investigation individually and collaboratively to produce data to serve as the basis for evidence, and in the design: decide on types, how much, and accuracy of data needed to produce reliable measurements and consider limitations on the precision of the data (e.g., number of trials, cost, risk, time), and refine the design accordingly.
Evaluate a Solution to a Real World Problem is a performance expectation related to Engineering Design HS-ETS1.
Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics as well as possible social, cultural, and environmental impacts.
Evaluating potential solutions-In their evaluation of a complex real-world problem, students: Generate a list of three or more realistic criteria and two or more constraints, including such relevant factors as cost, safety, reliability, and aesthetics that specifies an acceptable solution to a complex real-world problem; Assign priorities for each criterion and constraint that allows for a logical and systematic evaluation of alternative solution proposals; Analyze (quantitatively where appropriate) and describe* the strengths and weaknesses of the solution with respect to each criterion and constraint, as well as social and cultural acceptability and environmental impacts; Describe possible barriers to implementing each solution, such as cultural, economic, or other sources of resistance to potential solutions; and Provide an evidence-based decision of which solution is optimum, based on prioritized criteria, analysis of the strengths and weaknesses (costs and benefits) of each solution, and barriers to be overcome.
Refining and/or optimizing the design solution: In their evaluation, students describe which parts of the complex real-world problem may remain even if the proposed solution is implemented.