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Stephen T. Beckett's The Science of Chocolate is an excellent overview of the scientific and engineering principles that go into chocolate production. It begins with a brief look at the history of chocolate and then moves forward to address how chocolate progresses from the cocoa bean to the chocolate bar in a store. The book follows the diagram presented early on about the major steps of chocolate making (cocoa bean preparation, cocoa liquor manufacture, mixing, grinding, etc.), and thus is well organized. Because of the book's format, a non-technical reader can still appreciate the extensive journey of cocoa as it becomes the prototypical chocolate bar, coating, or filling. Also included in the book are glimpses into industry standards, packaging, and nutrition myths and truths about chocolate and its production.
As a reader, the strength of this book is its repetition of key chocolate-making variables. For example, The Science of Chocolate continually mentions the topic of chocolate flow and points to it as a parameter of interest in the first half of the book. By the time chocolate flow is addressed in detail in Chapter 5, the reader is already aware of the importance of the topic. Chocolate flow/viscosity, fat content and structure, and crystallization are emphasized so heavily that when their respective chapters come about, the reader is clued in to their significance.
From a food science/engineering perspective, this book is very thorough on several topics. The extensive discussion of sugars and milk (Chapter 2), fats (throughout the book, but especially Chapter 6), and other additives such as emulsifiers and chemicals to prevent fat bloom has an authentic basis in organic chemistry but are stated simply, for the most part. In my opinion, the most complete, technical parts of the book are Chapters 4 and 5. These chapters look at liquid chocolate and its flow properties and bring up some interesting points. The section on quantifying the viscosity of chocolate as two primary parameters, yield value and plastic viscosity, is novel. Many individuals, myself included, usually consider viscosity to be a single, one-size-fits all variable, but Beckett points out the need for a different system when describing chocolate. Also, particle size is revealed to affect plastic viscosity and yield value in different ways than I had expected (I won't ruin it for potential readers, but for those with the book, I am referring to pages 88-90).
Principles of materials science also come into play somewhat, such as in the exploration of the crystallization of triglycerides. On this occasion, Beckett could have catered to his scientific audience a little more and focused more deeply on the crystal structures instead of glossing over them by comparing them to the stacking of chairs. A single projection looking on the ends of the triglyceride chains is presented in a figure and never discussed.
The mechanical aspects of the chocolate-making process are covered moderately well in the text. The descriptions of cocoa bean size compensation, winnowing, and roasting are whole, but the milling section is the most comprehensive. It addresses several types of mills, and the clear descriptions of these make the equipment able to be envisioned. This is particularly important because the equipment diagrams are often lacking. Some are overly dark, others are uselessly intricate, and many are not tied well to the text. Overall, I recommend that readers stick to the text unless the supplementary images are plots or actual photographs. Related to this point, a large issue I have is the lack of scale mentioned in the diagrams, photographs, and text. It is often difficult to picture the equipment because no numerical quantity is given for its volume or throughput. I finished the book with little idea of how many grinders or roasters a chocolate company might have in an average-sized production facility or how much cocoa one of these operations can handle.
The book concludes with a quick look at packaging, industry standards, and nutrition facts related to chocolate. These are useful but kept to an appropriate level of brevity. In the end, I recommend this book for readers with a moderate science background. Though sizing discussions are blatantly omitted from the book, there is a strong foundation in the examination of fluid flow, fat effects, and particle size.