Chemistry of food

10 Key excerpts on "Chemistry of food"

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  eBook - PDF

  Introduction to Food Chemistry

  • Richard Owusu-Apenten(Author)
  • 2004(Publication Date)
  • CRC Press

    (Publisher)

  The preceding sections represent a necessarily brief review of general chemistry. Readers should continue to cultivate their understanding of chemistry during their study of food chemistry. Two websites, one from MIT and the other from Purdue University are especially useful for reviewing general chemistry topics. A further useful resource is a site devoted to chemistry for nutrition sciencec. 1.5 FOOD CHEMISTRY 1.5.1 DEFINITION AND ScoPE Food chemistry is the application of chemistry principles to the food system. There is emphasis on the Chemistry of food components, including macroconstituents (water, carbohydrates, 0 http:/ jchemed.chem. purdue.edu/ genchemjtopicreview/, http:/ jweb.mit.edujesgbiojwwwjchemjreview.html, and http:// nutrition.jbpub.com/discovering/chemistry_review.cfm 12 Introduction to Food Chemistry lipids, and proteins), microconstituents (for example, flavors, vitamins, minerals, sweeteners, general additives), and their interactions. Food chemistry emerged as a discipline after World War II. The mission statement for food chemistry is to ensure a supply of food, which is nutritious, safe, and affordable, with due regard for the environment. This mission is shared by the other food sciences including food microbiology, food processing, food engineering, and food law. After World War II, the emerging discipline of food science brought together a host of basic sciences (chemistry, mathematics, microbiology, and engineering) in a bid to improve the food supply. Food science (singular), the scientific study of foods and the food system, described in Section 1.5, is an assemblage of many sub-disciplines or food sciences, including food chemistry, food engineering, food microbiology, and food law. At first there was a clear emphasis on food processing and the chemical transformations encountered during processing. Advances were made in understanding the Maillard reaction, which leads to colored and flavored compounds during processing.

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  Analytical Chemistry of Foods

  • Sujata Nagnath Mustapure(Author)
  • 2020(Publication Date)
  • Arcler Press

    (Publisher)

  Fundamentals of Food Chemistry 1 CONTENTS 1.1 Introduction ......................................................................................... 2 1.2. Historical Aspects ............................................................................... 3 1.3. Gross Chemical Composition of The Foods ......................................... 4 1.4. Pre-Eminent Constituents of Food Chemistry ..................................... 10 1.5. Pre-Eminent Terms In Food Chemistry ............................................... 11 1.6. Tactic To Study of The Food Chemistry ............................................... 14 1.7. Societal Role of The Food Chemists ................................................... 18 References ............................................................................................... 20 Chapter Analytical Chemistry of foods 2 1.1 INTRODUCTION Food science is a multidisciplinary topic including biology, chemistry, engineering, and microbiology food chemistry is a science that deals with properties and the chemical composition of food and chemical variations it undergoes (Maga, 1982; Belitz et al., 2004; Otles, 2005). The field of food chemistry as an autonomous branch of the science was formed in the nineteenth century in parallel with the increasing interest in the quality of food and the overturning of food falsification and adulteration (Mottram et al., 2002; Stadler et al., 2002). New techniques of food analysis permitted us to characterize and discover not only the main nutrients (such as lipids, proteins, and carbohydrates) but also important minor components like vitamins and important minerals and lastly, thousands of micro and minor constituents being natural components of food (such as natural antioxidants, natural coloring matters, aroma compounds,).

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  The Chemical Element

  Chemistry's Contribution to Our Global Future

  • Javier García-Martínez, Elena Serrano-Torregrosa(Authors)
  • 2011(Publication Date)
  • Wiley-VCH

    (Publisher)

  2 The Role of Chemistry in Addressing Hunger and Food Security Jessica Fanzo, Roseline Remans, and Pedro Sanchez

  2.1 Chemistry is the Backbone of Food and Nutrition

  Chemistry has provided the backbone in understanding the structure, organization and functions of living matter. Biochemistry, in particular, is composed of the structural chemistry of living matter, the metabolism or chemical reactions of those living matters, and the molecular genetics of heredity. The ability of plants to derive energy from sunlight and animals and humans to derive energy from food begins with chemistry and the principles of thermodynamics, and the basics of food itself are made of chemical and biological structures – amino acids, sugars, lipids, nucleotides, vitamins, minerals and hormones.

  The chemical elements are key to understanding our modern day food and nutritional needs. In the late 18th century, many of the chemical elements had been defined, including nitrogen from ammonia, followed by the discovery of protein in egg albumin, inorganic elements and amino acids. The characterization of energy and calorimetry were also critical for the food and nutrition science world and could not have been understood without the use of physiological chemistry [1]. By studying persons engaged in labor and exercise and the amount of heat released, and understanding metabolics, the kilocalorie was defined – the energy needed to raise the temperature of 1 kg of water by 1 degree Celsius.

  Starting in the 1800s, scientists worked backwards by characterizing disease states and, from defined foods, they discovered what was lacking or deficient, honing in on specific vitamins and minerals. For example, in the 1880s, deficiency of thiamin through fractionation of rice polishing was discovered to cause beriberi. In 1870, vitamin C deficiency was discovered to be the root cause of scurvy [1]. In the mid 1700s, British naval commander James Lind pleaded with the British Navy to make citrus foods available on all sea voyages. In a book he authored after an especially long journey with high mortality among the crew, he described miracle cures achieved with the use of lemon juice. Almost 60 years later, the British Navy did provide citrus foods when Captain Cook succeeded in avoiding scurvy altogether by giving his sailors lime juice on three successive voyages (between 1768 and 1779) [2]. It was not until later that scientists established the definitive link between scurvy and vitamin C (ascorbic acid) deficiency. Chemistry not only identified these critical elements for human health but defined what is considered “essential” for sustaining life (see Table 2.1

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  Science in Nursing and Health Care

  • Tony Farine, Mark A. Foss(Authors)
  • 2013(Publication Date)
  • Routledge

    (Publisher)

  7 Biological molecules and food Learning outcomes After reading the following chapter and undertaking personal study, you should be able to:

  1  Identify the seven components of the diet.

  2  Outline the chemical structure of carbohydrates, fats and proteins.

  3  Describe how carbohydrates, fats and proteins are digested and outline their use within the body.

  4  Outline the roles of vitamins and minerals within the body.

  5  Describe a healthy diet.

  6  Outline the relationship between the different nutritional groups, health and illness.

  Introduction

  If you were to list the most important health issues affecting our society, what would you include? There are many, but within any list of health threats some, such as heart disease and obesity, are related to diet. If you have read Chapter 3 , you may have wondered how quickly you would be able to relate chemistry to health care. Healthy eating is one example of a subject in which knowledge of chemistry is helpful, since foods are chemicals. To begin with, we return to a distinction made in Chapter 3 – organic chemistry and inorganic chemistry . Organic chemistry is the study of compounds that contain carbon; this is important here, since most components of the diet are organic compounds. Inorganic chemistry is the study of substances that do not contain carbon; some nutrients are inorganic substances.

  Diet and food The components of the diet may be divided into seven groups:

    carbohydrates

    proteins

    lipids (fats)

    vitamins

    minerals

    water

    fibre (roughage/non-starch polysaccharide).

  All of these are important substances in food, but there are significant differences between them. For example, not all are organic compounds. Water is not, and neither are the minerals. Some, such as the carbohydrates, proteins and lipids, have to be digested (broken down) before they can be absorbed, while vitamins, minerals and water are absorbed unchanged. Finally, fibre is neither digested nor absorbed but provides bulk to food and is important in the maintenance of formed faeces that pass readily through the intestines.

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  Physiological Ecology

  How Animals Process Energy, Nutrients, and Toxins

  • William H. Karasov, Carlos Martínez del Rio(Authors)
  • 2020(Publication Date)
  • Princeton University Press

    (Publisher)

  SECTION TWO Chemical Ecology of Food The Chemistry and Biology of Food CHAPTER T WO T O EAT AND to be eaten are central themes in ecology. Food chemistry deter-mines what animals eat and it often shapes the strategies that both animals and plants use to avoid being eaten. Thus, thinking about food’s chemistry is some-thing that ecologists do (or should do) quite often. This chapter is an introduction to a topic that we will refer to again and again throughout the book. Investigating the chemical composition of food can be done at a variety of levels of detail. The organization of this chapter reflects these levels. We begin by describing “proximate analysis” (PA), a commonly used (and misused) method that yields a very gross breakdown of food’s constituents into “fractions” that are assumed to correspond to broad classes of chemical compounds. We describe the assumptions of proximate nutrient analysis and its many limitations. Then we use the fractions that PA yields to describe food’s main chemical components (carbohydrates, proteins, lipids, minerals, and secondary metabolites; figure 2.1) and to comment on the biological roles that they play. 2.1 Getting Started; First Catch (Store and Prepare) the Hare Suppose that you believe that it would be useful to know the chemical composi-tion of the food eaten by the animal that you study. Maybe you suspect that variation in food chemistry explains food preferences, or that nutrient content correlates with some measure of performance (growth, reproduction, or sur-vival). Unfortunately, analyzing a food’s chemistry can rapidly become complicated and expensive. Thus, it is fairly unlikely that you will have the equipment necessary to do all the analysis that you want. Wisely, you decide to 50 C H A P T E R T W O Figure 2.1. The compounds present in food can be divided into broad cate-gories.

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  Food Processing Operations and Scale-up

  • Kenneth J. Valentas, J. Peter Clark, Leon Levin(Authors)
  • 2020(Publication Date)
  • CRC Press

    (Publisher)

  4 Food Chemistry I. Scope of Chapter Those engaged in processing food should understand the basic chemistry and physics of food materials. Often the engineer in the food processing industry has acquired just enough knowledge of food chemistry to size a heat exchanger, design a piping system, and so on. This information has often been obtained in an unstructured way dependent on need and is essentially a random walk in the world of food chemistry. This chapter is designed to pull together some basic concepts of food chemistry that are of particular interest for engineering applications. For those desiring a more in-depth discussion the reader is referred to Fennema’s (6) textbook, which is detailed and also contains a wealth of useful references. II. Enzymes and Human Nutrition It is difficult to discuss food in an entirely objective manner because everyone has likes, dislikes, prejudices, and opinions. For those of us engaged in processing food, it is important to understand the basic chemistry and physics of food materials. The ultimate purpose of food is to sustain biological systems, and, in this case, the human organism is the prime concern. There is considerable controversy over the role of foods and food ingredients in human nutrition. Nutrition is a very complicated science and the subject of extensive research. It is not possible to treat the subject in any depth here. Still, it is important for engineers to understand the fundamentals of human nutrition even if on a very elementary level. III. Human Chemical Factory It is instructive to view the human body as a chemical factory with specific inputs and outputs, such as shown in Fig. 1. In this simplified model, foods or nutrients that can be categorized chemically as lipids, proteins, carbohydrates, water, minerals, and vitamins along with oxygen, which is obtained from the air we breathe, are utilized by the body to support life

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  Education and Training in Food Science

  • I D Morton, J Lenges(Authors)
  • 1991(Publication Date)
  • Woodhead Publishing

    (Publisher)

  Nutrition science is in many ways related to food science but does not belong to this discipline.

  Concentrating first on food science, we can see that many areas in this field are of particular importance [1 ]; these can be enumerated as follows:

  1. The study of the properties of both raw and prepared foodstuffs. 2. The study of the composition of foodstuffs and the properties of their individual components.

  3. The study of the changes in composition and properties during manufacturing, preparation and storage; the development of methods for measuring these changes and of procedures to delay or to prevent unwanted changes.

  4. The assessment of quality, wholesomeness and safety of foodstuffs (this also comprises the content of nutrients and the organoleptic properties). 5. The recognition of harmful organisms and components in foodstuffs and, where possible, the development of methods to prevent or eliminate these. 6. The development of methods of analysis for establishing the composition of foodstuffs and for the determination of harmful or otherwise undesirable components in foodstuffs. 7. The development, in cooperation with lawyers and others, of adequate food laws, designed to protect public health and to promote fairness in trade.

  It is obvious that chemistry is a very important tool for all these areas, particularly for the items indicated by the numbers 2, 3 and 6. For this reason, any curriculum for food scientists and technologists should embrace an education in chemistry. It must be emphasized that, on the other hand, curricula in food chemistry should contain courses in other fields having relevance to food science and technology.

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  Introducing Food Science

  • Robert L. Shewfelt, Alicia Orta-Ramirez, Andrew D. Clarke(Authors)
  • 2015(Publication Date)
  • CRC Press

    (Publisher)

  Section IV

  Scientific Principles

  Passage contains an image

  Chapter 11

  Food Chemistry

  As a Chemistry major, Ignacio was more interested in what toxic chemicals the microbes made than in the microbes themselves. He was also interested in all the chemicals that were added to foods, like preservatives, but he wasn’t so sure that he wanted all those chemicals in his mouth. While he was looking for an elective course online during open registration, he came across one called Food Chemistry. It sounded interesting, like it might be a course where he could apply his basic knowledge in chemistry to the real world. He took the course, loved it, and found out that he had much more to learn about the chemicals in his food. Much of what he learned changed his understanding of and appreciation for chemistry in everyday life.

  Jennifer, by now a committed vegan, decided to major in Nutrition because she wanted to learn how to eat healthier. We can imagine her shock when she learned that nutrition is mainly about chemicals and how they act in the body. It really doesn’t have much to do with food at all. There was in-depth study of digestion and all the metabolic pathways that occur to food components once they are broken down, but healthy eating wasn’t exactly the main topic of discussion. When her professors talked about a vegetarian diet, they had some good things to say but also a lot of negative things. Mostly, they talked about chemicals. They talked about large chemical compounds like carbs (only they called them carbohydrates), fats (lipids), and proteins. She learned that vitamins are actually organic chemicals and that minerals are elements straight from the periodic table she had memorized (and quickly forgotten) in first-year chemistry. She wanted to know more about nutrients, but she wanted to know about the nutrients in the types of foods she ate regularly.

  Kyle is a Food Science major and is learning more about all the chemicals in his foods. He learned about the toxins and preservatives Ignacio was into, as well as about the nutrients that Jennifer was studying. He was fascinated by the many other chemicals in foods and how they all work together to produce the quality of a food. He found out that foods are made of ingredients and ingredients are made of chemicals. Each ingredient has a function in the food, but it is actually the chemical components that give an ingredient its function. The more he learned about pigments and stabilizers, the more he wanted to learn about texturizers and humectants. He thought that the taste of a food was simple, but now he knows that flavor combines taste and aroma. He learned that tens and even hundreds of chemical compounds could be contributing to the aroma of foods. Upon completion of his degree, Kyle plans to go to graduate school to learn more about food chemistry and then to work in the food industry to develop new food products.

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  The Handy Nutrition Answer Book

  • Patricia Barnes-Svarney, Thomas E. Svarney(Authors)
  • 2015(Publication Date)
  • Visible Ink Press

    (Publisher)

  FOODS DEFINED What is the definition of food?

  The definition of food is complex, mainly because that one word describes a number of things. In general, food covers anything we eat that has (and sometimes does not have) a nutritious value to maintain our health.

  When it comes to nutrition and health, what matters is the way we approach our foods. For instance, we have to make a selection of foods that keep us healthy; we have to choose a cooking method (and recipe) that will not only match our cooking skills, but also be the most nutritious way to cook the foodstuff; and we have to make sure we eat enough—or not too much—of certain nutritious foods to maintain our health.

  What are some chemical constituents of food?

  Chemically speaking, almost all foods contain some type of carbon—from vegetables to meat. The biggest reasons for the different chemical compositions of foods are the source of the foods and the nutrients (or non-nutrients) they contain—for instance, from animals and plants to fungi, or from vitamin C and zinc to water.

  How are certain nutrients destroyed—other than by cooking methods?

  Various nutrients in foods are affected by cooking (see this chapter)—but also by other methods, such as the mechanical action of milling. For example, vitamin B5 (pantothenic acid) decreases in foods, depending on the process: It decreases by about 33 percent during cooking; it is easily destroyed by heating in acids, such as vinegar, or basic sources (alkali), such as baking soda; about 50 percent is lost by the milling of flour that contains the vitamin; and a high, dry heat—such as that employed during dehydration of foods containing vitamin B5 —also destroys much of this vitamin.

  INSIDE MEATS How is meat defined?

  In general, no matter what animal—from cows and lambs to pigs and buffalo—the “meat” many people eat is most often defined as the flesh of animals. Some people also define “meats” as only the flesh from mammals—or those raised for human consumption—but not from fish and sea creatures, poultry, and other organisms, even though these other animals also supply water, protein, fats, and carbohydrates. Another common way to define meats is as “red versus white” meats: The red meats “turn red” when proteins (myoglobin) in the animal’s narrow muscle fibers are exposed to oxygen; most adult mammals (cows, cattle, sheep, etc.) are considered this type of meat. White meat refers to certain muscle fibers in an animal that are broader than those found in red meat—and usually includes the breast meat of chicken and turkey.

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  Fundamentals of Sustainable Chemical Science

  • Stanley E. Manahan(Author)
  • 2009(Publication Date)
  • CRC Press

    (Publisher)

  10. BIOLOGICAL CHEMISTRY 10. BIOLOGICAL CHEMISTRY 10.1. BIOCHEMISTRY 10.1. BIOCHEMISTRY Many people have had the experience of looking through a microscope at a single Many people have had the experience of looking through a microscope at a single cell. It may have been an ameba, alive and oozing about like a blob of jelly on the cell. It may have been an ameba, alive and oozing about like a blob of jelly on the microscope slide, or a bacterial cell stained with a dye to make it show up more microscope slide, or a bacterial cell stained with a dye to make it show up more plainly. Or it may have been a beautiful algal cell with its bright green chlorophyll. plainly. Or it may have been a beautiful algal cell with its bright green chlorophyll. Even the simplest of these cells is capable of carrying out a thousand or more chemical Even the simplest of these cells is capable of carrying out a thousand or more chemical reactions. These life processes fall under the heading of reactions. These life processes fall under the heading of biochemistry biochemistry , that branch , that branch of chemistry dealing with the chemical properties, composition, and biologically of chemistry dealing with the chemical properties, composition, and biologically mediated processes of complex substances in living systems. mediated processes of complex substances in living systems. Biochemical phenomena that occur in living organisms are extremely sophisti-Biochemical phenomena that occur in living organisms are extremely sophisti-cated. In the human body, complex metabolic processes break down a variety of cated. In the human body, complex metabolic processes break down a variety of food materials to simpler chemicals, yielding energy and the raw materials to build food materials to simpler chemicals, yielding energy and the raw materials to build body constituents, such as muscle, blood, and brain tissue. Impressive as this may body constituents, such as muscle, blood, and brain tissue.

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