“Ice cream anyone?” The utterance of such words is usually sufficient to get people’s attention and put a smile on their faces, especially on a hot summer day. So what is so special about ice cream and what makes one better than another? As the name suggests ice-cream is essentially “frozen cream” and can be traced back to 200 BC when the Chinese froze a mixture of milk and rice by packing it into the snow. The explorer, Marco Polo apparently saw ice-creams being made during a trip to China and introduced the delicacy to Italy in the 13th century, with various recipes popping up across Europe after that.
Ice cream only became a global sensation the second half of the 20th century when cheap refrigeration meant it was no longer necessary to have your own “ice house” to enjoy. This global proliferation made ice cream big business with different brands, different flavors and different products appearing over time – all competing for our business and praying annually for a hot summer.
We all have our favorite brands of ice cream. What makes one brand more likable than other brands? Well, there are a number of attributes which give an ice cream its sensorial appeal, however, one of the most important attributes in addition to flavor is its texture. Ice cream is a complex rheological material which can be thought of as a solid foam, containing air bubbles trapped in a frozen emulsified matrix of water, fat, protein, sugar and stabilizers, the combination and interaction of which is fundamental to its rheological behavior and ultimately its texture.
How ice cream should look and feel will depends on the particular stage of the eating process. Ideally it should hold its ice/foam structure until it gets in to the mouth and then should melt in such a way as to give a smooth rich texture on the palette. Getting this desired effect requires optimization of the rheology, and this requires using the right combination of ingredients at the right concentration, and processing them in the right way in order to get the optimum microstructure. This is far from a trivial task, however, rheometry is a tool that can help; not just to characterize the end product but to assist in engineering the correct rheology in the first place.
The art of cooking and food preparation is just as important as the ingredients that make up the food. Rheology is the best science we can choose to bridge the gap between the art of food making and human acceptance and I would like to show you how to do it. If your interested then why not join me on 12th June when I will be discussing this exact topic – how to evaluate ice cream texture through rheological measurement. Hope to see you there!
UPDATE: click here to view a recording of the webinar: Why does ice cream taste smooth or gritty? It depends on the rheology!