Difference between revisions of "Food Science"

From Science Olympiad Student Center Wiki
Jump to: navigation, search
(Simple Sugars=)
(Simple Sugars)
Line 72: Line 72:
  
 
The "Sugars" on food label consist of mono- and di-saccharides. That's why you see sugar in milk; that's lactose, not added by the manufacturer.
 
The "Sugars" on food label consist of mono- and di-saccharides. That's why you see sugar in milk; that's lactose, not added by the manufacturer.
 +
 +
===Complex Sugars===
 +
Complex sugars are mainly polysaccharides. Polysaccharides are chains of many, many monosaccharides, most commonly glucose.
 +
 +
Polysaccharides are divided into two main groups, storage polysaccharides and structure polysaccharides.
 +
 +
====Storage Polysaccharides====
 +
Storage polysaccharides are our main sources of energy. There are two main storage polysaccharides: glycogen and starch.
 +
 +
Glycogen is the storage polysaccharide found in animals.
 +
 +
Starch is the storage polysaccharide found in plants. We humans consume a lot of it, such as in pasta or potatoes.
 +
 +
Starch comes in two forms: amylose and amylopectin. Amylose is a straight chain of glucose molecules which coils up. Amylopectin is branched. Since there are more ends to be broken down in amylopectin, amylopectin is more quickly digested.
 +
 +
When you look at a food label, the Dietary Fiber and Sugars don't quite add up to the Total Carbohydrate; the remainder is starch.
 +
 +
====Structure Polysaccharides====
 +
Structure polysaccharides are polysaccharides meant to give structure. Two common structure polysaccharides are celluose and chitin.
 +
 +
Celluose is better known as dietary fiber. It is insoluble, meaning indigestible by our bodies, so it cleans out our insides and comes out as feces.
  
 
===Proteins===
 
===Proteins===

Revision as of 21:17, 9 April 2012

Food Science
& Event
Forum Threads
2012 2011 Trial
Tests
There are no images available for this event
There are no question marathons for this event
This event was not held recently in Division B
This event was not held recently in Division C


Food Science was a Trial Event in states such as Texas and North Carolina for quite a while. When it is run in Texas as a trial, it differs from many other states. This is Food Science's debut year.

The Event

This event consists of doing some lab testing, and some written testing. It requires a viscosity station, plus 8 other stations relating to foods in the rules. This makes for 9 stations. The rules say that you may have even more than this.

Macromolecules

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

Lipids have many subcategories, such as fats, waxes, and sterols.

Fats

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. Triglyceride.gif 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

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. CisvsTrans.jpg 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.

Sterols

The one sterol you'll want to know about is cholesterol. Cholesterol, like all sterols, come in this form:

Sterol.png (picture credit Wikipedia)

Cholesterol comes in LDL, "bad" cholesterol, and HDL, "good cholesterol". HDL is made by your liver, while LDL is generally consumed. Some types of foods, such as trans fats, are thought to raise LDL and lower HDL.

If you have too much LDL, your heart arteries will clog and as a result, you will get a heart attack. This is cardiovascular disease, the leading cause of death in America.

Carbohydrates

Carbohydrates, are, as implied, hydrates of carbon. They consist of carbon, oxygen, and hydrogen atoms. The formula for a carbohydrate can be expressed as Failed to parse (Missing <code>texvc</code> executable. Please see math/README to configure.): C_m(H_2 O)_n , where most commonly Failed to parse (Missing <code>texvc</code> executable. Please see math/README to configure.): m and Failed to parse (Missing <code>texvc</code> executable. Please see math/README to configure.): n are the same.

Carbohydrates consist of simple sugars, monosaccharides and disaccharides, and complex sugars, polysaccharides.

Simple Sugars

Simple sugars consist of single sugar units, monosaccharides, and disaccharides, which are made up of monosaccharides. Common monosaccharides include:

  • Glucose(also dextrose)
  • Fructose(also levulose)
  • Galactose
  • Mannose

Common disaccharides include:

  • Sucrose(glucose+fructose)
  • Lactose(glucose+galactose)
  • Maltose(only found as a byproduct of hydrolysis of starch)(glucose+glucose)

Simple sugars are small and easy to break down, therefore give you energy quite soon after you consume simple sugars, but run out quickly, leaving you tired.

The "Sugars" on food label consist of mono- and di-saccharides. That's why you see sugar in milk; that's lactose, not added by the manufacturer.

Complex Sugars

Complex sugars are mainly polysaccharides. Polysaccharides are chains of many, many monosaccharides, most commonly glucose.

Polysaccharides are divided into two main groups, storage polysaccharides and structure polysaccharides.

Storage Polysaccharides

Storage polysaccharides are our main sources of energy. There are two main storage polysaccharides: glycogen and starch.

Glycogen is the storage polysaccharide found in animals.

Starch is the storage polysaccharide found in plants. We humans consume a lot of it, such as in pasta or potatoes.

Starch comes in two forms: amylose and amylopectin. Amylose is a straight chain of glucose molecules which coils up. Amylopectin is branched. Since there are more ends to be broken down in amylopectin, amylopectin is more quickly digested.

When you look at a food label, the Dietary Fiber and Sugars don't quite add up to the Total Carbohydrate; the remainder is starch.

Structure Polysaccharides

Structure polysaccharides are polysaccharides meant to give structure. Two common structure polysaccharides are celluose and chitin.

Celluose is better known as dietary fiber. It is insoluble, meaning indigestible by our bodies, so it cleans out our insides and comes out as feces.

Proteins

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.

Viscosity

Testing

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.

Competition Tips

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.