How Do You like Your Chocolate?

With spring comes Easter – a time when chocolate is at the top of the shopping and eating list. ;-) That is why we ask you today: How do you like your chocolate? Straight from the fridge for a satisfying crunch? Or slightly warmer for a smoother mouthfeel?

You may have already noticed: The temperature of chocolate sig­nificantly influences the sensory experience during bit­ing and chewing. Here comes NETZSCH into play!

This sensory perception can be quantified using the axial capabilities of the Kinexus rotational rheometer equipped with a parallel plate geometry setup. A con­trolled downward and upward movement of the upper plate simulates jaw motion during mastication.

To illustrate this, we placed a piece of chocolate on the lower plate of the rheometer. The initial gap (distance between the upper and lower plates) was set to 3 mm. The upper plate then moved downward at a constant speed of 30 mm/s to a nominal gap of 1 mm before returning to its initial position. We recorded the normal force required for this movement, and this cycle was repeated one time. We conducted the test on chocolate at 10°C (refrigerated) and 35°C (mouth temperature).

Headline

What we found out:

Figure 1 shows the variation in gap size (blue curve) and the force required to reach it (orange curve). As expected, the higher the temperature, the more easily the chocolate is compressed. At 10°C, a force of 50 N resulted in a compression of only 150 μm, preventing the upper plate from reaching the target gap of 1 mm. In contrast, at 35°C, only 3.7 N was needed to compress the chocolate to 1 mm.

These results highlight the significant impact of tem­perature on the chewing sensation and emphasize the importance of proper storage for an optimal chocolate experience.

We hope you enjoy your chocolate and wish you Happy Easter!

Find out more about NETZSCH Kinexus Rotational Rheometers:

• 
  Kinexus Prime ultra+

  High-end rheometer for highest demands

  • Torque range - viscometry: 1.0 nNm to 250 mNm
  • Torque range - oscillation: 0.5 nNm to 250 mNm
• 
  Kinexus Prime lab+

  Rotational Rheometer for Quality Control with SOP

  • Torque range - viscometry: 10 nNm to 200 mNm
  • Torque range - oscillation: 5.0 nNm to 200 mNm
• 
  Kinexus Prime pro+

  For research and development

  • Torque range - viscometry: 5.0 nNm to 225 mNm
  • Torque range - oscillation: 1.0 nNm to 225 mNm