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Macromolecules are very large molecules. They are conventionally four different biopolymers: Lipids, carbohydrates, proteins, and nucleic acids. The last does not apply to Food Science therefore we only need to pay attention to the first three. In each of these categories of macromolecules, some subcategories exist.
Lipids have many subcategories, such as fats, waxes, and sterols.
Fats are a good source of energy, giving 9 kcal/g of fat. The daily recommended amount of fat intake is limited to 65g.
Fats are most commonly found as triglycerides. Triglycerides are made up of a glycerol backbone with three fatty acids attached. Fatty acids are long chains of carbon molecules with an ester group on the end. The fatty acids may be saturated, unsaturated, or trans. Triglycerides can use any combination of these different fatty acids.
Saturated Fatty Acids
Saturated fatty acids are one long chain of carbon atoms, no double bonds, no fancy stuff. Saturated fats are generally bad for you since they clog your arteries, increasing the risk of heart attack and stroke. Since the carbon atoms in a saturated fatty acid are pack closely together, saturated fats are usually solid at room temperature. Saturated fats are generally found in animals.
Unsaturated Fatty Acids
Unsaturated fatty acids are also a long chain of carbon atoms, this time with one or more double bonds. Unsaturated fatty acids with one double bond are monounsaturated, and those with two or more double bonds are polyunsaturated. Unsaturated fats are generally better for you when not overeaten because they may help lower blood cholesterol level. Since double bonds exist, these fatty acids are much more wobbly and therefore are usually liquid at room temperature. Unsaturated fats are generally found in plants such as nuts and seeds. They are also found in fish as omega-3 unsaturated fatty acids.
Omega-3 Essential Fatty Acids
Omega-3 essential fatty acids are found in fish and in plants. The name means there exists a double bond three carbon atoms from the non-ester end of the chain. (Omega is the last letter in the Greek alphabet.) These fatty acids are "essential" because your body cannot produce them and they are vital for normal metabolism.
Trans fats are not found in nature, although recent studies show that there may be small amounts. Trans fats are unsaturated fatty acids heated up, then made so "dizzy" that cis bonds flip over into trans bonds. Trans fats are unhealthy for you since they lower HDL (good cholesterol) and raise LDL (bad cholesterol). The recommended daily intake should be limited to 2g per day.
Carbs consist of starches and sugars. In this event, the most common types of sugars you have to know are monosaccharides and disaccharides. Glucose, galactose and fructose are the three most common mono. and Maltose, Sucrose, and Lactose are the most common disaccharides. Starches are long chains of (most commonly) glucose that have two forms: amylose and amylopectin.
Proteins are polymers of amino acids. They are a source of Nitrogen in the diet and are necessary to live. Most protein rich food is eggs.
At the competition, you may be given a written test along with a lab. The most common test that you are expected to perform are Benedict's, Burets, Sudan IV/III, Grease Spot test, and Iodine. Benedict's tests for reducing sugars, Burets for proteins, Sudan and grease spot for fats and Iodine for starches. More in depth info about these test and their procedure can be found online.
You may also have to know about the periodic table. Know how to read chemical formulas, chemical bonds, and knowing what the abbreviations are.
Stations may be a way the event is run. Generally you will be crunched for time at some stations, and be left with too much time at others. If you are at a station that involves math, and you then run out of time; write down the numbers and question and use your extra time at the other stations to finish that question.
Because this event is new even when you feel lost, you may be surprised at how well you place. This event has little specific information available at this time, so a good binder is key.