Vassilis Kontogiorgos - Introduction to Food Chemistry

This Springer imprint is published by the registered company Springer Nature Switzerland AG

The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

The complexity of food chemistry makes it a challenging subject for students studying in a food science programme. Although there are excellent food chemistry books available in the market, they are either encyclopaedic or not pitched correctly to undergraduate food science students. These problems create difficulties for students to identify what is essential, how much they need to know or find links between the chemistry of food components and its relevance to applications.

The present textbook bridges this gap. It employs the latest pedagogical theories in textbook writing to present the subject to food science students and links chemistry with food processing, quality and shelf life.

From a students perspective, the book has specific learning objectives for each chapter and is self-contained, so students do not need to search for essential information outside the textbook. The present book has didactic elements with information being conveyed with figures, colour-coded schemes and graphs, annotations on figures that link it to the text descriptions, and learning activities at the end of each chapter linked to the learning objectives.

Lecturers can also use this book to help them focus teaching preparation on key aspects of food chemistry relevant to both industry and modern research. The present textbook may also support lecturers with exam preparation, assignments, and other assessments or learning activities.

Some prerequisite knowledge is necessary to make the best use of the book. The reader must have knowledge of general chemistry and general organic chemistry to be able to follow the concepts presented in this textbook.

The book is organised into eight chapters covering structures, chemistry and functionality of all components found in food. Concepts from the physical chemistry of foods (e.g. glass transition and gelation) and food analysis are also introduced and explored in each chapter. At the end of each chapter, there are learning activities to help with the revision of essential concepts. Several exercises require access to the Internet, and occasionally more advanced concepts are introduced, and the learner can explore them at their own pace. Answers to some of the activities are provided in the Appendix. Additional food chemistry books and review articles on current food chemistry topics are presented in the bibliography. These resources have been used in one way or another in the preparation of the current textbook. None of the resources is older than 2000, and the majority of them are since 2010.

Now, let us get started with water and explore why it is so special for food stability.

Water is an essential food constituent, and its content varies significantly across different products. For example, there are foods like fruits or meat products with a water content of ~95% or ~ 70%. In contrast, there are foods with a limited amount of water ranging between 10 and 20%. As several chemical and enzymatic reactions need water to occur, it serves as a solvent of water-soluble ingredients and a medium for diffusion. Water is also essential for the growth of beneficial (e.g., lactic acid bacteria) and spoilage (e.g., Pseudomonas) microorganisms. During food processing, it is crucial to calculate the correct amount of water in the formulation to achieve the specified products consistency and optimum shelf life stability. For instance, minor deviations in water content in bakery products may result in quality losses and rejection of the final product. It is also of economic concern, as it adds weight to the product and increases shipping costs. It should be stressed that irrespectively of the processing, food always contains a certain amount of water that is not possible to remove entirely. For example, wafers or potato crisps that are particularly dry foods have a remaining water content of ~5%. As a result, controlling and predicting water behaviour is very important in food processing. The first step to control water in foods is to understand its structure, chemical, and physical properties. Especially important are the mechanisms with which it interacts with the various food constituents, as it is most frequently the underlying reason for product stability. This chapter presents all the essential information needed to explore the broad area of water functionality in foods.