The ‘Molecular Gastronomy – Science in the Kitchen’ module is intended for the Nature, Life and Technology (NLT) lessons. The module was certified on 17 June 2010 by the NLT Steering Committee for use on the VWO in domain H (Materials, Process and Production Technology). The certification number of the module is X218-059-VH. The original certified module is available as a pdf download from http://www.betavak-nlt.nl. There is an explanation on this website about the amendments that lecturers are permitted to make to the module, for use in the lesson, without breaching the certification. This module was developed by Authors Elma Schenkelaars – lecturer in Chemistry/NLT Ids Klompmaker- Wageningen University Ties van de Laar- Wageningen University Scientific expert Erik van der Linden – Wageningen University In collaboration with Jeroen Sijbers – NLT support team Eral Osmanoglou- Wageningen University Inge van den Heijkant- Wageningen University Brenda Terpstra- lecturer in Chemistry/NLT Maarten van Dongen- lecturer in Chemistry/NLT Cazimir ten Brink - Wageningen University Amended versions of this module can only be distributed if mention is made in this colophon that it is an amended version, quoting the name of the author of the amendments. Materials that students require for this module are available from the NLT classroom: http://www.vaklokaal-nlt.nl/ © 2010. Version 1.0 The copyright for this module belongs to Wageningen University. Wageningen University is therefore the rightful claimant as indicated in the creative commons licence stated below. When developing the module the authors used material from third parties with their permission. The greatest possible care has been taken to trace and comply with the rights to texts, illustrations, etc. However, should there be persons or institutions who believe they own the rights to parts of text, illustrations, etc., of a module, they are requested to contact Wageningen University. The module has been carefully composed and tested. Wageningen University, Landelijk Ontwikkelpunt NLT, Steering Committee NLT, SLO and authors do not accept any responsibility for inaccuracies and/or omissions in the module. Moreover, Wageningen University, Landelijk Ontwikkelpunt NLT, Steering Committee NLT, SLO and authors do not accept any responsibility for any damage that occurs as a result of (the use of) this module. This module is covered by a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 licence http://creativecommons.org/licenses/by-nc-sa/3.0/nl Table of Contents Table of Contents....................................................................................................... 3 1 Introduction ........................................................................................................ 4 1.1 The cook and the scientist .................................................................................. 4 1.2 Molecular gastronomy...................................................................................... 7 1.3 Structure of the module .................................................................................... 9 2 The basis ......................................................................................................... 11 2.1 Can we do you a flavour? .................................................................................. 16 2.1.1 Taste .............................................................................................. 16 2.1.2 Smell .............................................................................................. 22 2.1.3 Texture ............................................................................................ 26 Blancmange, ice-cream, wafers, pasta, whipping cream and crisps .................................... 27 2.1.4 Visual aspects ..................................................................................... 27 2.2 Measuring flavour ......................................................................................... 28 2.3 From basic components to structures .................................................................... 35 2.4 From ingredients to basic components ................................................................... 40 2.4.1 Water ............................................................................................. 41 2.4.2 Carbohydrates .................................................................................... 42 2.4.3 Proteins ........................................................................................... 46 2.4.4 Fats ................................................................................................ 50 3 Emulsions ........................................................................................................ 52 3.1 What is an emulsion? ...................................................................................... 54 3.2 Water and hydrogen bonds ............................................................................... 56 3.3 Fats and hydrophobic interactions ........................................................................ 56 3.4 Emulsifiers (surfactants) ................................................................................... 58 3.5 Emulsions in the kitchen ................................................................................... 64 3.5.1 Cream and butter ................................................................................. 64 3.5.2 Vinaigrette ........................................................................................ 67 3.6 Stability of emulsions ...................................................................................... 68 3.7 Emulsions in the molecular gastronomical kitchen ...................................................... 71 3.7.1 Making molecular butter ......................................................................... 71 3.7.2 Mayonnaise… with a difference! ................................................................ 73 3.7.3 Aioli ................................................................................................ 73 4 Foams ............................................................................................................. 74 4.1 The role of proteins in a foam ............................................................................. 76 4.2 The role of sugars in a foam ............................................................................... 82 4.3 The stability of foams ...................................................................................... 86 4.3.1 Drainage .......................................................................................... 86 4.3.2 Disproportionation ............................................................................... 88 4.3.3 Coalescence ....................................................................................... 91 4.4 Examples of foams in the molecular gastronomical kitchen ............................................ 92 4.4.1 How proteins ensure the formation of a beautiful champagne foam ......................... 92 4.4.2 Zabaglione ........................................................................................ 92 4.4.3 The same foam – different proteins ............................................................. 93 4.4.4 Making espumas with the gourmet whip ....................................................... 94 5 In conclusion ..................................................................................................... 95 6 Glossary .......................................................................................................... 96 7 URL list.......................................................................................................... 101 1 Introduction 1.1 The cook and the scientist A cook and a scientist sit down for a chat about food. It soon transpires that they are both talking a completely different language. The words dishes, food, measuring equipment, structures, recipes, taste, cooking, molecules and ingredients are thrown about. They are both passionate about their trade, but if they can’t understand each other, they will never be able to work together. How can they interconnect this muddle of words so that they can understand each other? The following diagram may help. Figure 1 How the cook and the scientist look at food. Figure 1 is the ‘framework' for this module. It shows that the food scientist and the cook take a different view on the same food. This diagram will be deconstructed during the module. Ask an Italian to name a recipe and he will probably say pasta. For example, pasta with sun-dried tomato and a pesto and crème fraiche sauce. This dish contains pasta, pesto, crème fraiche, sun- dried tomatoes, leeks, mushrooms and onion. A cheese sandwich is also a dish. It consists of bread spread with butter and filled with cheese. Butter, bread and cheese are called foods. The ingredients of a dish are foods. Foods are in turn made up of ingredients. Molecular Gastronomy June 2010 -4- Assignment 1 1. Think of your favourite dish, or a dish that you have recently eaten and liked. 2. Try and describe the taste of this dish. 3. Now try and describe why you like it. You have probably already noticed from Assignment 1 that it is not easy to describe the taste of a dish. On the one hand, the term ‘taste’ refers to the five basic tastes of sweet, sour, salty, bitter and umami (we will come back to the meaning of umami later). This definition of ‘taste’