The research has so far analysed foam technologies under zero-gravity on the ground and under on ‘parabolic’ flights in aeroplanes to produce more stable bubbles. ConfectioneryNews can confirm that Nestlé plans to move the experiment to space by 2015.
The research is analysing the foam structure of a milk protein mix, which could have applications in improving the quality, texture and shelf-life of aerated chocolate, with eventual application in Aero bars.
Foam technology issues
Speaking to ConfectioneryNews.com, Nestlé senior scientist Cecile Gehin-Delval said that there were several technologies used to make aerated chocolate, including vacuuming and gas models.
“The existing technology to control bubble size and distribution is difficult,” she said.
The bubbles can collapse and there is a need to control the matrix, she continued.
“For foam, one of the main problems is drainage,” she said.
Drainage occurs due to the density of the bubbles, which leads bubbles to move to the surface of a product.
Gehin-Delval said that drainage can lead to coalescence, whereby two bubbles touch and burst to form a larger one, thus affecting the quality and texture of the chocolate.
She added that pressure differences between large and small bubbles meant smaller bubbles were sometimes pulled into larger bubbles in so called Ostwald ripening.
All the negative effects seem to occur due to the presence of gravity.
The AEROplane experiment
The ‘parabolic’ flight experiment analysed the foam structure of six 5ml samples of water and milk protein in a special machine aboard a A300 airbus plane.
The plane flew at a maximum height of 28,000 ft (8,500m), and made about 30 ‘parabolas’, or up-and-down dips, creating weightlessness inside the fuselage in short bursts.
Researchers analysed the stability of the foam during these short bursts, which lasted 20 seconds each.
Zero gravity aerated chocolate: the potential
The implications of the research for aerated chocolate are still a long way off.
Nestlé head of R&D communications Hilary Green told this site that research was still “at the very elementary stages”.
However, scientists hope that zero-gravity could hold the key to stopping drainage and improving aerated chocolate quality and texture.
“Drainage is only due to gravity,” said Gehin-Delval, adding that Nestlé hoped to profit from the research in time in multiple applications such as coffee and mousses.
The company will obtain the results from the parabolic flights by the end of 2014.
It then plans to work with the International Space Station (ISS) to send an astronaut to space to conduct the same experiment.
Parolbolic flights can only give short 20-second bursts of zero-gravity, but the conditions in space are infinite.
Nestlé appears to be looking at other new ways of producing aerated chocolate.
It recently filed a US patent for making aerated confectionery using nitrogen gas at an elevated pressure, which it claims gives an improved soft texture and sensory properties. (See HERE )