Article pubs.acs.org/jchemeduc
Laboratory Development and Lecture Renovation for a Science of Food and Cooking Course Deon T. Miles* and Adrienne C. Borchardt Department of Chemistry, Sewanee: The University of the South, 735 University Avenue, Sewanee, Tennessee 37383-1000, United States S Supporting Information *
ABSTRACT: Several years ago, a new nonscience majors course, The Science of Food and Cooking, was developed at our institution. The course covered basic scientific concepts that would normally be discussed in a typical introductory chemistry course, in the context of food and food preparation. Recently, the course has been revamped in three major ways: (1) the incorporation of a laboratory component, (2) the reorganization of the lecture topics, and (3) the inclusion of a field trip. A weekby-week explanation of the course curriculum is provided, as is the description of the laboratory experiments conducted during the course. A brief description of the group excursion to a local distillery is given. KEYWORDS: Curriculum, Laboratory Instruction, Microscale Lab, Nonmajor Courses
■
INTRODUCTION In 2009, an article in this Journal described a new course for nonscience majors, The Science of Food and Cooking, taught at our institution during the Spring 2007 and Fall 2007 semesters.1 At the time, the course was inspired by the emphasis on the science of food and cooking in popular literature and media.2−8 We were not the only ones, however, that thought teaching this topic would be beneficial to students that are not majoring in the sciences. There are several institutions that teach similar classes, whether in a semesterlong course or shortened version (e.g., January term or Maymester).9 It is noted that some of these courses do not have a laboratory component associated with them. Since the initial offering, thoughts about improving our course have been suggested by former students and colleagues. Three major changes have been implemented in the most recent offerings of the course: (1) the incorporation of a 12week laboratory component, (2) the reorganization of course topics for better alignment with a typical general chemistry text, and (3) the inclusion of a field trip to observe the science of food and cooking in a real world setting. These changes to the course are described in this article. At our institution, there are eight learning objectives that must be completed for the General Education Program, which is a vital part of the liberal arts education experience. The course described here can be used to fulfill one of the learning objectives, under the label “Observing−Experimenting−Modeling (Experimental/Experiential)”. All students at our institution are required to complete three courses with this designation. The description of this requirement is provided below. © 2014 American Chemical Society and Division of Chemical Education, Inc.
The study of the natural world through careful observation, construction and testing of hypotheses, and the design and implementation of reproducible experiments is a key aspect of human experience. Scientific literacy and the ability to assess the validity of scientific claims are critical components of an educated and informed life. Scientific and quantitative courses develop students’ ability to use close observation and interpret empirical data to better understand processes in the natural world. As they create models to explain observable phenomena, students develop their abilities to reason both deductively and inductively.10 This course was developed with this description in mind: providing a suitable option for students who will likely not major in science but will develop the ability to understand and interact with scientific material and concepts. In each of the Fall 2012 and 2013 semesters, 16 students were enrolled in the course. The course was aimed primarily at first-year students, though some upperclassmen were in the class. Students that have taken an algebra course and a chemistry course in high school should have adequate preparation to complete this course. This course provided students with important information about food and cooking that they can use throughout their lives. Students learned what happens to the food they prepare when certain ingredients are added or when certain outside stimuli interact with the food. The lecture portion was taught over 28 class periods of 75 min each, whereas the laboratory portion included 12 3-h sessions. Teaching methods used in this course include lecture, Published: September 19, 2014 1637
dx.doi.org/10.1021/ed5003256 | J. Chem. Educ. 2014, 91, 1637−1642
Journal of Chemical Education
Article
in this experiment and was used in subsequent laboratory experiences throughout the course.
instructor−student discussion, instructor demonstrations, video instruction, group excursion, and hands-on experimentation. To reinforce concepts taught during the lecture, students viewed portions of episodes from the Good Eats series.8 In the previous offerings of the course, students watched entire episodes of this series at the end of each lecture; here, particular segments of the videos were viewed at different moments within the lecture to highlight the important concepts.
Titration of Fruit Juices
The citric acid content in a selection of fruit juices was determined using titration with a standardized NaOH solution.13 Students in the course were required to pool their data to provide a comprehensive analysis of the various fruit juices under study. In addition, because a polyprotic acid was being investigated here, the importance of reaction stoichiometry was emphasized.
■
LABORATORY COMPONENT In the first two offerings of this course, there was no laboratory component. In end-of-course evaluations, students expressed their desire to have a laboratory experience associated with the course. In particular, students wanted to have a laboratory component that would involve food preparation or cooking of some nature. This would be a clear benefit for students that are experiential or kinesthetic learners. Unfortunately, at our institution, there was no laboratory space available that could be deemed “food safe”, limiting the options for food preparation during the laboratory experience. This is a shortcoming of the course, and creative solutions to this problem will be explored in future offerings of the course. It should be noted that in the laboratory setting, students were reminded often that they should not taste or ingest any of the food. Any food-grade items that were brought into the laboratory were considered laboratory chemicals and were for laboratory use only. Students were also told to not remove any remaining food-grade items at the end of a laboratory experience. After a thorough search for appropriate laboratory experiments, in this Journal and other sources,11−18 the laboratory component was developed and implemented into the course. A brief description for each experiment that was incorporated is provided below. A summary of the emphasized scientific concepts and skills are provided in Supporting Information Table S-1.
Vitamin C Analysis
The amount of vitamin C in fruits and fruit juices was determined using a redox titration.13 The concept of dietary reference intake (DRI) was explained in this microscale experiment. Microscale Analysis of Calcium in Milk
The microscale titration of calcium in milk samples with ethylenediaminetetraacetic acid (EDTA) was accomplished in this experiment.13 The amount of calcium in the milk samples was calculated by the comparison with a reference CaCl2 solution. Spectrophotometric Determination of Food Dyes in M&Ms
Students used a tabletop spectrophotometer to measure the absorbance of three food dye solutions (Red 40, Yellow 5, and Blue 1).14 Standard solutions of Blue 1 dye were prepared, and using the Beer−Lambert law, the amount of blue dye in a brown M&M was determined. The spectral properties that result from mixing the food dyes were examined as well. Calorie Content in Nuts
Using a simple aluminum can calorimeter, the amount of energy per unit mass released by the combustion of several nuts was calculated.15 Students were challenged to build and improve their experimental apparatus throughout the experiment. (Caution: Proper ventilation was important for conducting this experiment safely.)
Conservation of Mass
The Law of Conservation of Mass was studied in this experiment.11 The classic reaction between baking soda and vinegar was carried out in an open system and a closed system. Using an analytical balance, the mass of the reactants was recorded before the reaction, as well as the subsequent mass of the products. Differences between masses before and after the reaction under these two conditions were explained.
Determination of Iron Content in Foods by Spectroscopy
In this experiment, different food samples were heated until they were reduced to a fine ash.16 HCl was added to dissolve the iron in this residue; the mixture was then filtered, and a thiocyanate solution was added to the filtered mixture to form a colored complex ion. The absorbance of the iron−thiocyanate complex ion was measured using a tabletop spectrophotometer. This absorbance was compared to a Beer−Lambert plot that was produced from the absorbances of standard solutions of the complex ion. (Caution: Proper ventilation was important for conducting this experiment safely.)
Determination of Sugar Content in Commercial Beverages by Density
The density of several commercial beverages (e.g., Coke, fruit punch) was determined in this experiment.12 Solutions of known sugar concentration (0−20 wt %) were prepared, and the density was determined by massing a known volume of each solution using volumetric glassware. A calibration curve (density vs wt % sugar) was prepared from the standard solutions, and the density of the commercial beverages was calculated from this curve. The use of a computer-based graphing program (e.g., Microsoft Excel) was required to make the calibration curve.
Quantifying a Colligative Property Associated with Making Ice Cream
Freezing point depression was examined by preparing two samples of homemade ice cream with two different salts in the surrounding ice−salt mixture.17,18 The difference between using NaCl and CaCl2 in the ice−salt mixture was quantified. The molality of the water−salt mixture was calculated, and a comparison of the observed and the expected freezing point depression was explained. It should be noted that this experiment was the only one where students could eat something that was produced from the laboratory. Therefore, the preparation of the ice cream was performed in an area outside of the teaching laboratory.
Food Testing: Carbohydrates, Proteins, and Fats
The identification of the biochemical nutrientscarbohydrates, proteins, and fatsin foods was the focus in this experiment.13 Using several reagents that produce a particular reaction with the appropriate nutrient, foods were classified into one of the aforementioned categories. Microscale analysis was introduced 1638
dx.doi.org/10.1021/ed5003256 | J. Chem. Educ. 2014, 91, 1637−1642
Journal of Chemical Education
Article
(decanting, filtering, and distillation) were explained. Also, typical kitchen measurements and conversions were introduced.
The laboratory component was evaluated through maintenance of laboratory notebooks and submission of written reports. For the notebooks, students were encouraged to include the date and title of the experiment on the first page, complete the prelaboratory exercise, provide clearly labeled data tables, and include example calculations. The formal report, which was submitted electronically, was composed of several sections: Introduction, Experimental, Results and Discussion, and Appendix. The laboratory notebook and report were assessed based on the completeness of the work, the accuracy and precision of the data, the interpretation of the data, the explanation of the relevant chemistry, and the clarity, grammar, and spelling of the writing. During the last laboratory period, students gave an oral presentation that was 15 min in duration. Students worked in pairs and chose their topic based solely on their interest in the subject. This allowed the students to have a sense of enthusiasm that would be curtailed if their topics were assigned. Some examples of presentation topics included Chemistry of Wine Making, Carbonation of Commercial Beverages, Rock Candy, Moonshining, and Chemistry of Absinthe. The presentation was assessed based on its scientific content, the integration of media, as well as the delivery and subject knowledge of the presenters. The presentations were also peerevaluated using these aforementioned categories.
Molecules and Nomenclature
How atoms are bonded together was introduced here, as well as the foundations for speaking in “the language of chemistry”. The different representations of a molecule (e.g., molecular formula, line structure, and ball-and-stick model) were introduced. The systematic naming of ionic compounds (and polyatomic ions) was explained. Calculations
The concept of the mole was introduced. Students were taught how to do basic unit conversions using dimensional analysis. This was primarily done to help students comprehend the size of the molecules that are in the foods they eat. Balancing Equations and Organic Compounds
The ability to balance chemical equations is a fundamental skill for chemistry. Students were given the opportunity to practice balancing simple chemical equations related to cooking (e.g., combustion, oxidation). In addition, because most food molecules are composed primarily of carbon, hydrogen, and oxygen atoms, the ability to identify basic hydrocarbons (i.e., normal alkanes) and functional groups (e.g., alcohol, carboxylic acid) was introduced.
■
Stoichiometry
Preparing solutions is a central part of what happens in the kitchen. The ability to dilute solutions properly was explained, and how to describe the strength of a solution in terms of concentration was covered. The concept of limiting reactant was playfully explained using s’mores as a class demonstration.
REORGANIZATION OF LECTURE TOPICS The course topics were reorganized in the most recent offerings of the course. This reorganization was done to allow for the course content to be taught from a typical general chemistry textbook. More importantly, the reorganization of the course was an improvement on how the material was built upon throughout the course. In the earlier offerings, the topics were organized primarily by types of food (eggs, milk, meat, and so forth). There were several concepts that were piled together in this method. For example, for eggs, the concepts that were covered ranged from gas laws to protein structure in one lecture. This approach was too haphazard for the students to learn the material effectively. In the most recent offerings, we start with building a foundation of concepts (as what is done in a typical general chemistry text) and then branch off into more complex concepts. In the updated version, for example, students were introduced to concepts about bonding first, and then the more complex topic of protein structure came later in the course. The description of lecture topics is provided below. A summary of the emphasized scientific concepts are provided in Supporting Information Table S-2.
Solubility
The difference between the behavior of electrolytes (e.g., NaCl) and nonelectrolytes (e.g., sugar) dissolved in water was explored. The rules of solubility were covered, but care was taken to exclude the exceptions to minimize confusion. The composition of hard water, which can have significant impact on cooking, was described. Methods to counteract hard water, primarily through the use of ion-exchange resins, were discussed. Acids and Bases
The identification of acids was important since there are numerous foods (in particular fruits and vegetables) that contain a significant amount of acid. Because most acids in foods are polyprotic acids, this concept was explained as well. Bases, which are used primarily as acidity regulators in industrial food preparation settings, were described as well. The effects that changes in acidity have on food were discussed.
Introduction and Scientific Method
Redox Reactions
The four basic food molecules (carbohydrates, proteins, fats, and water) were introduced. The scientific method was explained in context of how to prepare a dish (from planning to cooking to analysis). Similarities between cooking recipes and scientific literature were examined.
Combustion of simple hydrocarbons, a primary heat source for cooking, was covered. The ability to identify an oxidation− reduction reaction, from the changes in oxidation number, was introduced. The relationship between free radicals and antioxidants was discussed.
Physical and Chemical Changes
Egg Chemistry and Gases
The three primary states of matter (gas, liquid, and solid) were described with respect to ice cream, which contains all three states simultaneously. The classification of matter was examined with food-related examples (e.g., chocolate chip cookie dough ice cream is a heterogeneous mixture). Examples of physical and chemical changes in the kitchen were presented. Three methods used in the kitchen related to physical changes
The basic structure of a hen’s egg, as well as the function of the components, was described. A thorough explanation of the creation and versatility of an egg white foam was presented. Two gas laws, Boyle’s law and Charles’s law, were related to baking a cake and a soufflé, respectively. The challenges associated with baking at higher altitudes were discussed. The 1639
dx.doi.org/10.1021/ed5003256 | J. Chem. Educ. 2014, 91, 1637−1642
Journal of Chemical Education
Article
solubility was examined, with examples of solids and gases dissolved in liquids at different temperatures. The difference in solution saturation (i.e., unsaturated, saturated, or supersaturated) was explored in the context of sugar confectioneries.
classification of leavening agents (i.e., biological, chemical, and mechanical) was described. The use of modified atmosphere in food packaging was mentioned. Energy and Diets
Colligative Properties
The difference between thermal and chemical energy, and their relationship to kinetic and potential energy (respectively), was explored. A student-centered discussion of dietary guidelines, with ancillary readings,19−23 was conducted.
The concept of freezing point depression and boiling point elevation were discussed by examining ice cream and sugar confectioneries, respectively. Osmosis was described with respect to how the cellular structures of foods change that are exposed to a salt brine. A considerable amount of time was spent on food colloids and emulsions. With emulsions, the concepts of hydrophobicity and hydrophilicity were described, as was the difference between oil-in-water (e.g., mayonnaise) and water-in-oil (e.g., vinaigrette) emulsions.
Heat and Cooking Methods
The three common forms of heat transfer (conduction, convection, and electromagnetic radiation) were described. Basic cooking methods (e.g., grilling, steaming, microwaving) were discussed, as was the importance of browning reactions (i.e., caramelization and Maillard reactions) in the flavor development of cooked foods.
Lewis Structures and Organic Chemistry
Students were introduced to Lewis theory to provide a basis for drawing simple hydrocarbon molecules. Particular focus was paid to the bonding behavior of the carbon atom, the fundamental atom for the majority of the food molecules. The concept of isomers was introduced, with the focus being on the designation between cis and trans isomers. The ability to identify a trans isomer was beneficial for discussions of hydrogenation reactions and trans fatty acids. Aromatic hydrocarbons were described as well to assist with the identification of aroma compounds (e.g., phenolic compounds). The concept of polymerization was described as well, in the context of plastics that are used in industrial food preparation.
Calorimetry
The concept of heat capacity was explained, with respect to the large value that is attributed to water (a common cooking medium). The description of coffee-cup calorimetry in lecture was used to prepare students for the laboratory experience “Calorie Content in Nuts”, where an aluminum can calorimeter was used to determine the amount of heat generated by the combustion of various nuts. Taste and Flavor
The three common states of matter (solid, liquid, and gas) were described in order to set up the discussion of the differences between taste, odor, and flavor. Taste is related to the detection of molecules dissolved in liquids by taste buds in the mouth, whereas an odor is associated with gas-phase molecules that are detected by receptors in the nose. Students learned that flavor is a combination of these two sensations. Different molecules that are responsible for various tastes and aromas were identified. The use of pungent chemicals (e.g., capsaicin) in food preparation was discussed as well.
Ethanol
A thorough comparison of ethanol and water was done, along with a description of fermentation, a typical source of ethanol. A significant amount of time was devoted to discuss the physical effects of alcohol intoxication on the body. Other functional groups (e.g., ketones, esters) were described as well, with the focus on the ability to identify these chemical structures (they are usually associated with aroma compounds).
Intermolecular Forces
Lipids
The relationship between intermolecular forces and physical properties (e.g., melting point) was examined. Two physical properties in particular, viscosity and capillary action, were discussed fully with appropriate food-related examples. The process of distillation was described, as were the differences between batch and continuous distillation. A special phenomenon, the “legs” of alcoholic beverages, that highlights the properties of intermolecular forces was discussed.24
The difference between fats and fatty acids was emphasized, as well as that of saturated and unsaturated fatty acids. The structure of a triglyceride was described. The differences in the properties of animal fats and vegetable oils were discussed. The ability to identify an omega-3 fatty acid was another point of focus. The two major types of rancidity associated with fats (oxidative and hydrolytic) were discussed. The differences between “good” and “bad” cholesterol were explained as well.
Water and Solids
Carbohydrates
The unusual properties of water (e.g., high specific heat, high heat of vaporization) were discussed. Methods to clean and filter water at the consumer and industrial levels were described. The effect of water hardness on cooking was explored. For solids, the different types of solids were described in context of kitchen cookware. The concept of alloys was covered here when considering cast iron and stainless steel cookware.
The differences between simple and complex carbohydrates were explored. These differences were probed further as the designation between monosaccharides, disaccharides, and polysaccharides were explained. Some attention was given to the global epidemic of diabetes, with an explanation of what the disease does to the human body. This discussion led into an explanation of sugar substitutes (e.g., artificial sweeteners, sugar alcohols).
Solutions and Solubility
Proteins
The description of gaseous, liquid, and solid solutions were covered. The difference between a solution and a suspension was explained. The concept of vitamin solubility was introduced, with a focus on the differences in chemical structure leading to the designation of water-soluble vs fatsoluble vitamins. The relationship between temperature and
The hierarchal system of protein structure (i.e., primary, secondary, tertiary, and quaternary) was described. The typical functions of different proteins were discussed. The effects that cooking has on proteins, in terms of protein denaturation and coagulation, were explained. The structure of meat was described, as was how the structure changes when heat is 1640
dx.doi.org/10.1021/ed5003256 | J. Chem. Educ. 2014, 91, 1637−1642
Journal of Chemical Education
Article
topic they experience daily. The understanding of the scientific concepts associated with food and of food preparation was the main focus of this course. The course topics have been reorganized from a previous offering of the course, a significant laboratory component was added, and a field trip was included. The ability to incorporate more cooking into the course is a desire in future offerings, but there are limitations based on the available resources. Despite any potential shortcomings, it is hoped that this enhanced course will be a staple of the class offerings at our institution for years to come.
applied. Methods to preserve meat were explained, which led to a discussion of food borne illnesses.
■
GROUP EXCURSION A group excursion to a nearby whiskey distillery (Jack Daniel’s Distillery in Lynchburg, TN) was incorporated in the course.25 The field trip was taken during a laboratory period near the end of the course. This allowed for enough time to travel to and from the facility, as well as tour the distillery, in a timely manner. It should be noted that this distillery has a “sampling tour”, but this was not made available to the students in the course. The tour started with a short video about the history of the distillery. Then, the group moved to a rickyard, where stacks of sugar maple boards were burned (under low oxygen conditions) to make the charcoal that was used for “mellowing” the whiskey. After seeing the first building and water source on the grounds, the group moved to the still house, where the mash (consisting of water, yeast, and three grainsmalted barley, corn, and rye) fermented to produce ethanol and carbon dioxide. After the fermentation process, distillation on an industrial scale was on display, where the filtered mash was converted to “moonshine”, a high-proof distilled spirit. In the next part of the facility, the charcoal mellowing building, the moonshine was dripped through huge charcoal-filled vats to “mellow” the whiskey. This process removed some of the heavier flavor components. Finally, the group walked through a barrel house, where the whiskey will age several years before bottling. A portion of the bottling facility was also part of the tour. The opportunity for the students to observe a full-scale facility that manufactures whiskey was a beneficial “real world” experience that echoed some of the concepts that were discussed in the lecture. Although this course took a group excursion to a distillery, there are other examples of field trips (e.g., winery, dairy, and bakery) that can be an extension of the laboratory experience.26,27
■
ASSOCIATED CONTENT
S Supporting Information *
Tabular summary of the course, student demographic information, laboratory experiment handouts, course schedule, course syllabus. This material is available via the Internet at http://pubs.acs.org.
■
AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected]. Notes
The authors declare no competing financial interest.
■
ACKNOWLEDGMENTS The authors would like to thank all of the students that were enrolled in this course. The authors would also like to thank Ken Walsh from the University of Southern Indiana for thoughtful discussions and the reviewers for helpful comments.
■
REFERENCES
(1) Miles, D. T.; Bachman, J. K. Science of Food and Cooking: A Non-Science Majors Course. J. Chem. Educ. 2009, 86 (3), 311−315. (2) McGee, H. On Food and Cooking; Scribner: New York, 2004. (3) Wolke, R. L. What Einstein Told His Cook; W. W. Norton & Company, Inc.: New York, 2002. (4) Wolke, R. L. What Einstein Told His Cook 2; W. W. Norton & Company, Inc.: New York, 2005. (5) Barham, P. The Science of Cooking; Springer-Verlag: Berlin, 2001. (6) Hillman, H. The New Kitchen Science; Houghton Mifflin Company: New York, 2003. (7) Corriher, S. O. Cookwise: The Hows and Whys of Successful Cooking; HarperCollins: New York, 1997. (8) Good Eats. Internet Movie Database. http://www.imdb.com/ title/tt0344651/ (accessed March 2014). (9) Symcox, K. Using Food to Stimulate Interest in the Chemistry Classroom; American Chemical Society: Washington, DC, 2013. (10) General Education Program and Requirements - Revised. Sewanee Academics. http://academics.sewanee.edu/site/59712 (accessed April 2014). (11) Duffy, D. Q.; Shaw, S. A.; Bare, W. D.; Goldsby, K. A. More Chemistry in a Soda Bottle: A Conservation of Mass Activity. J. Chem. Educ. 1995, 72 (8), 734−736. (12) Henderson, S. K.; Fenn, C. A.; Domijan, J. D. Determination of Sugar Content in Commercial Beverages by Density: A Novel Experiment for General Chemistry Courses. J. Chem. Educ. 1998, 75 (9), 1122−1123. (13) Cesa, I. Flinn ChemTopic Labs: Chemistry of Food; Flynn Scientific, Inc.: Batavia, IL, 2003; Vol. 23. (14) Aurian-Blajeni, B.; Sam, J.; Sisak, M. Sweet Chemistry. J. Chem. Educ. 1999, 76 (1), 91−92. (15) Laursen, S.; Mernitz, H. Would You Like Fries with That? The Fuss About Fats in Our Diet; Wiley & Sons: New York, 2000.
■
STUDENT FEEDBACK The end-of-course evaluations provided the students an opportunity to give feedback about the course. Student feedback on the course was positive in general. The comments were prompted by questions about the strengths and weaknesses of the course. Some of the more thoughtful comments included: • “I enjoyed the “Good Eats” videos shown in class and I thought they were really good at relating what we learned in class to the culinary arts. The trip to the Jack Daniels factory was also a very cool idea and actually relevant to the course.” • “Plenty of lab experience but focussed [sic] mostly on chemistry wish it focussed [sic] a little bit more on cooking.” • “There were a lot of labs, which meant it was a lot of work. Fair amount of homework, fair amount of tests and quizzes.” • “Chemistry is an abstract topic to begin with, applying it to food does make it easier to recognize certain phenomena.”
■
SUMMARY The goal of this course was to provide our nonscience majors an opportunity to complete their general education requirement for experiential learning with a renovated course on a 1641
dx.doi.org/10.1021/ed5003256 | J. Chem. Educ. 2014, 91, 1637−1642
Journal of Chemical Education
Article
(16) Adams, P. E. Determining Iron Content in Foods by Spectrophotometry. J. Chem. Educ. 1995, 72 (7), 649−651. (17) Sund, R. Quantifying a Colligative Property Associated with Making Ice Cream. J. Chem. Educ. 1989, 66 (8), 669. (18) Make Ice Cream in a Plastic Bag. Teachnet.com. http:// teachnet.com/lessonplans/science/plastic-bag-ice-cream-recipe/ (accessed March 2014). (19) Shaw, A.; Fulton, L.; Davis, C.; Hogbin, M. Using The Food Guide Pyramid: A Resource for Nutrition Educators. http://cnpp. usda.gov/Publications/MyPyramid/OriginalFoodGuidePyramids/ FGP/FGPResourceForEducators.pdf (accessed March 2014). (20) Archived MyPyramid materials. United States Department of Agriculture. http://www.choosemyplate.gov/print-materials-ordering/ mypyramid-archive.html (accessed March 2014). (21) Willet, W. C.; Skerrett, S. K. Eat, Drink, and Be Healthy: The Harvard Medical School Guide to Healthy Eating; Free Press: New York, 2005. (22) ChooseMyPlate.gov. United States Department of Agriculture. http://www.choosemyplate.gov (accessed March 2014). (23) Healthy Eating Plate and Healthy Eating Pyramid. Harvard School of Public Health. http://www.hsph.harvard.edu/ nutritionsource/healthy-eating-plate/ (accessed March 2014). (24) Silverstein, T. P. Why Do Alcoholic Beverages Have “Legs”? J. Chem. Educ. 1998, 75 (6), 723−724. (25) Tour Information for Jack Daniel’s Distillery. http://www. jackdaniels.com/visit (accessed July 2014). (26) Luck, L. A.; Blondo, R. M. The Grapes of Class: Teaching Chemistry Concepts at a Winery. J. Chem. Educ. 2012, 89 (10), 1264− 1266. (27) Peterman, K. E. Field Trips Put Chemistry in Context for NonScience Majors. J. Chem. Educ. 2008, 85 (5), 645−649.
1642
dx.doi.org/10.1021/ed5003256 | J. Chem. Educ. 2014, 91, 1637−1642
