FOOD SCIENCE 12 EXAM Flashcards
what are the areas of study within food science?
producing, processing, preparing, evaluating, and using food.
what does the statement “food science is part of food production from the ground up” mean?
this statement means food scientists consider all aspects of the food cycle, from the soil in which crops grow to the animals that feed on crops.
what is biotechnology?
using genetics to improve plants, animals, and microorganisms for food production
what is a superfood?
a food that is healthy, balanced, and full of nutrients
what are the food constituents looked at in class?
carbs, lipids, proteins, vitamins, minerals, and water
what are energy-producing nutrients? give examples.
nutrients that provide our body with energy. ex. carbs, lipids, proteins
what are non-energy producing nutrients? give examples.
nutrients that do not provide our body with energy but are essential. ex. vitamins, minerals, water
carbohydrates are made up of what 3 elements?
Carbon, hydrogen, and oxygen
carbs provide our body with how many kcals of energy per gram?
4 kcals per g
there are two types of carbs, what are they?
simple carbs (sugars) and complex carbs (starches and fibres)
there are two kinds of simple carbs/sugars. What are they and how many sugars are in each?
monosaccharides (1 sugar) and disaccharides (2 sugars)
what are the 3 monosaccharides? (they are simple and have one sugar each)
glucose, fructose, galactose
what are the 3 disaccharides? (they are made up of two sugars each)
sucrose (glucose + fructose)
lactose (glucose + galactose)
maltose (glucose + glucose)
simple carbs are valued for what?
their sweetness
what are the most sweet and least sweet sugars?
fructose is the most sweet and lactose is the least sweet
what is the formula for glucose?
C6H12O6
what is crystallization/ how does it occur?
when you add so much sugar as you raise the temperature of the solution that the solvent boils and begins to evaporate, the concentration of sugar gets so high, the sugar crystals separate
what is a polysaccharide?
a complex carb made up of chains of sugars
what is starch often used for?
to thicken foods (like making the blueberry pie or the Mongolian chicken)
what is diabetes?
a condition in which the body cannot regulate blood glucose levels
what is hypoglycemia?
when blood glucose levels are too low
what is hyperglycemia?
when blood glucose levels are too high
what are some reasons for carbs being added to foods?
to sweeten food, make candy, and make gels
what are lipids more commonly known as?
fats
what are the 3 categories of lipids?
triglycerides, phospholipids, and sterols
what is the main function of triglycerides? what are some other functions?
to keep the body warm by collecting in adipose tissue, which forms a thin layer under your skin and functions as an insulator. some other functions include: cushioning your kidneys from impact, keeps hair supple and hair glossy
what 3 elements are triglycerides composed of? what does its structure contain?
they are composed of carbon, hydrogen, and oxygen. their structure contains 3 fatty acids and 1 glycerol molecule
what are fatty acids?
fatty acids are organic compounds that have a carbon chain with attached hydrogen atoms and a carboxyl group at one end and a variable group at the other end.
what is a carboxyl group?
it’s when the carbon is double bonded to one oxygen and single bonded to OH (-COOH)
what is the simplest fatty acid called and how many carbons are in its chain?
the simplest fatty acid is called acetic acid and it has 2 carbons in its chain
how many kcals of energy per gram do triglycerides provide our body with?
9 kcals of energy per gram
what does oxidation in food cause and what types of foods are more prone to oxidation?
oxidation causes foods to become rancid (foul taste). foods that are high in fat are more prone to oxidation and therefore spoil quicker
what is tenderizing?
the use of lipids to help moisten baked goods
what is aeration?
using lipids to help baked goods rise by trapping air
what is an emulsion?
when lipids help keep liquids mixed that wouldn’t normally mix
what 4 elements are proteins made up of?
carbon, hydrogen, oxygen, and nitrogen
why is nitrogen crucial in protein?
because it is what separates proteins from carbs and lipids, and what gives proteins their versatility
what are proteins made up of?
they are made up of chains of amino acids, the building blocks of proteins
what are amino acids made up of?
they are made up of a carboxyl group (-COOH), an amine group (-NH2), and a variable group (changes)
what is the simplest amino acid and what is its variable group made up of?
glycine is the simplest amino acid. It’s variable group is made up of a single hydrogen atom
how do amino acids link together to form protein molecules?
amino acids link together via peptide bonds
there are two types of proteins, what are they?
fibrous proteins and globular proteins
what is a fibrous protein, where is it found and what does it do?
forms a rope-like structure, found in connective tissue, gives strength
what are globular proteins and what do they do?
they are compact structures and they function as carrier proteins
what is an example of a globular protein and what does it do?
hemoglobin is a globular protein that transports oxygen in the blood
what do protein molecules typically look like? what is the result of chemical change that causes proteins to uncoil and properties to be diminished?
protein molecules are typically coiled. the chemical change that causes proteins to uncoil and properties to be diminished is called denaturation
what are 3 ways proteins can be denatured?
changes in temperature (heating or freezing), mechanical treatment , changes in pH (increase or decrease)
where can protein primarily be found?
eggs, meat, fish, and nuts
why are nuts not a good source of main protein?
because they are too high in fat
why are soybeans a nutritional standout?
because they are 40% protein, high in fibre and polyunsaturated fatty acids and they reduce the risk of coronary heart disease
what are proteins often used for?
make
how many kcals of energy per gram do proteins provide for your body?
4kcals per gram
what happens when we digest proteins?
During food digestion, proteins are denatured and then hydrolyzed into smaller chains where they can be absorbed by the small intestine into the blood stream as individual amino acids. There, it travels to cells where genetic material assembles them into the proteins they need to perform the functions needed at that time
why are proteins not produced in the same amounts throughout your life?
as we grow, our needs change and therefore our bodies adjust to those changes in needs
what are 5 functions of proteins in our body?
to stabilize pH levels, new growth, pick up, deliver, and store materials and nutrients, fight infections through antibodies, and to provide us with energy.
how many amino acids do we need, how many of them do we make, and how many must we consume but are essential?
There are 20 amino acids we need, 11 which we make, 9 of which must be consumed but are essential
what are vitamins?
organic substances vital to life
what are minerals?
inorganic elements vital to life
what is a deficiency disease?
a disease caused by the lack of a specific vitamin
what is Rickets?
a vitamin D deficiency in children that causes soft, weak bones
what is Pellegra?
a niacin deficiency that causes skin eruptions, digestive and nervous disturbances, and mental decline
what is a precursor?
a compound that can be changed into a vitamin in the body. AKA provitamins
what is fermentation?
the chemical breakdown of a substance by organisms (bacteria, yeast, or mold)
what are 3 uses of fermentation?
fermentation extends the time food can be stored without spoilage, makes some food more enjoyable, and makes some food usable
what kind of process is fermentation?
anaerobic process, meaning it does not require oxygen
what are 3 drinks made using fermentation?
wine, coffee, tea
what kind of fermentation is Lactic Acid fermentation? what does it do? what did we make in class using this method?
it’s a type of bacterial fermentation that extends shelf life by lowering the pH of the solution which kills the bacteria that spoils food. We made pickles in class using this method
what does yeast fermentation involve/do?
it involves converting glucose into ethyl alcohol and carbon dioxide.
what 3 key principles have baking experts learned to make bread through yeast fermentation?
temperature is critical (27° is the best. if it’s too low the yeast won’t ferment. if it’s too high the yeast will die),
Sugar is needed (but not too much because it can slow it down),
Too much salt can slow down the process
what type of food is made using mold fermentation?
many cheeses
when mold grows on food, it usually leaves the food inedible but when used in fermenting certain food products, molds can be helpful. what are two examples of how molds can be helpful?
grains contain a cellulose coating that our bodies cannot metabolize. Mold fermentation breaks down this coating so we can eat grains and access their nutrients. another example is mold fermentation can alter the texture of certain foods to make them more pleasing to eat. It’s used in aging many cheeses like blue cheese
what is food spoilage?
the deterioration in a foods natural state
how can food spoilage be detected?
by using our senses
what are 5 factors that accelerate food spoilage?
air and oxygen, moisture, light, microbial growth, temperature
how does air/oxygen accelerate food spoilage?
air contains a high percentage of oxygen which causes oxidation, and oxidation accelerates food spoilage by leading to rancidity
how does moisture accelerate food spoilage? How can it be controlled?
moisture is caused by “free” water molecules (meaning they aren’t bound to something else). This leaves the water molecules exposed to bind with things that speed up spoilage. “Bound” water means it is already bound to something else and therefore slows down spoilage. This can be controlled by dehydration (removing water), freezing (changes water from liquid to solid, making the water unavailable to bind), or food additives (added specifically to bind the water making it less available)
how does light accelerate food spoilage?
exposure to light causes photodegradation (the deterioration of food caused by light)
how does microbial growth accelerate food spoilage?
certain microorganisms that begin to grow in food accelerates spoilage
how does temperature accelerate food spoilage?
high temperatures cause proteins to denature, emulsions to break, vitamins to be destroyed, moisture to be lost, and certain qualities to be diminished (colour, flavour, odour). Low temperatures can cause emulsions to break and leave certain foods like fruits and veggies susceptible to microbial growth if they thaw again and their skin cracks
how does freezing preserve food?
freezing foods doesn’t kill microorganisms but stops their growth until they are thawed.
what happens if foods are not properly packaged, then frozen?
they can develop freezer burn because of moisture loss
how long can frozen foods last in the freezer for?
6-12 months
what is freeze-drying?
a commercial process that combines freezing and drying to preserve food. It’s expensive but foods can last up to years when preserved this way
what is irradiation?
when food is exposed to a controlled amount of radiation for a specific amount of time to destroy organisms that would cause spoilage
what kind of gamma rays are used for irradiation and how does it work?
gamma rays are used and they inactivate enzymes and damage bacteria genetically
what is considered a suitable container/package?
strung enough to withstand transport , doesn’t change the taste of the food
how does MAP (modified atmospheric packaging) work? Why is it appealing to consumers?
by replacing the air inside a package with a gas mixture. It’s appealing to consumers because it doesn’t use food additives
what oxygen do in MAP?
helps preserve food appearance
what does carbon dioxide do in MAP?
suppresses microbial growth
what does nitrogen do in MAP?
maintains the balance of oxygen and carbon dioxide
what is aseptic packaging?
not recyclable but requires less energy to produce, they can be stored flat which means less energy to transport them (since fewer trucks are needed), and contain a higher product to package ratio
what is dehydration? How must dehydrated foods be stored?
dehydration is removing water from food. It must be stored in tightly sealed containers like jars
what are 3 benefits of dehydration?
longer storage, smaller weight/size, and convenience
how much of the original water content should remain when dehydrating food?
15-20%
what happens if temperatures are too high or low during dehydration?
If temperatures are too high you risk case hardening the food. If temperatures are too low you risk allowing the bacteria time to multiply
what’s the first step in canning?
cleaning/packaging food
what is the raw-pack method?
uncooked food is placed in a container that is then filled with boiling water and closed with a ring and lid
what is the hot-pack method?
food is heated in water to about 77°C and then packed into a container that is closed with a ring and band immediately
what is the second step of canning?
processing
what is water-bath processing?
food containers are heated in a boiling water canning kettle
what is pressure processing?
containers are heated under pressure in a pressure container
what is the process time of canning dependant on?
the size of the food/container and the material of the container (metal/glass)
what can improper canning lead to?
illnesses such as botulism (a foodborne illness caused by bacteria called Clostridium botulinum)
what is a food additive?
something added to food for a specific purpose
what are 4 reasons why food additives are used?
preservation, improving healthfulness, making food more appealing, and improving processing and preparation
what is fortification? give an example
adding nutrients not normally found in that food. an example is adding vitamin D to milk
what is restoration? give an example
returns nutrients to a food that were lost during processing. an example is putting vitamin C back into canned citrus juice
what is enrichment? give an example
returning nutrients that were lost and adding nutrients that weren’t there before. an example is many cereals
what is nitrification? give an example
adding nutrients to foods low in nutrients usually to replace a balanced meal. an example is protein bars and shakes
what is the most common use of food additives?
mostly to add flavours
why are most food additives artificial?
because the demand is too high for natural supply, they’re cheaper, and better for mass production
what is one common argument against food additives?
unknown long-term effects
who is responsible for food safety?
everyone
what is a foodborne illness?
an illness caused by eating food that has been contaminated in some way. AKA food poisoning
what is food infection?
when a pathogenic microorganism enters the body with a food that is ingested and causes illness
what is food intoxication?
when a microorganism enters the body with a food that is ingested and produces a toxin that causes an illness
what is the best way to prevent the spread of foodborne illnesses?
washing your hands often
what are other ways to prevent foodborne illnesses?
keeping a clean workstation when dealing with food, using separate cutting boards (to prevent cross contamination), tying hair up, covering clothes up, proper food storage
how should perishable food items be stored?
at 4°C
how should non-perishable foods be stored?
at room temperature but away from heat sources or damp areas
how should frozen foods be stored?
in a freezer around -18°C
what kind of cutting boards should be used to cute meat and what’s should we do with them?
plastic cutting boards and they should be sanitized regularly
what is a food commodity?
a raw material sold commercially (ex. sugar, eggs)
what is botulism? what microorganism causes it and what are the symptoms? What causes botulism?
Botulism is a type of food intoxication is a serious that causes nausea, vomiting, and paralysis. It is caused by Clostridium botulinum, a type of bacteria. Botulism is linked to improperly canned or preserved foods.
how does cost influence a consumer’s decision to buy a product?
consumers typically like to save money and don’t want to pay more than they have to. Usually if cheaper options of similar quality are available, that will be their first choice.
how does convenience influence a consumer’s decision to buy a product?
consumers enjoy convenient packages (ex. re-sealable, allowing for later use) but also convenient foods (ex. easy or quick to make) because of busy lives
how does quality influence a consumer’s decision to buy a product?
consumers are usually looking for products that taste good, that don’t spoil quick, and made with quality products
how does an environmentally friendly package influence a consumer’s decision to buy a product?
some consumers are environmentally conscious and like being able to recycle packages
how does appearance influence a consumer’s decision to buy a product?
consumers are usually drawn to products that look good/tasty
how does brand influence a consumer’s decision to buy a product?
consumers are sometimes drawn to specific brands because they’re reputable or based on previous personal experience with a brand in terms of good quality
how does healthfulness influence a consumer’s decision to buy a product?
consumers usually look for how healthy a product is, foods with less processing, foods that meet specific/individual diet needs
what is sensory data and how does it help food producers?
sensory data is data collected though the use of our senses, therefore through appearance, smell, taste, and feel. The data collected must be specific and it helps food producers evaluate their products and make the necessary changes
what are some things required to be present on food packages in Canada? what is the exception? What about something manufactured in Canada but destined for another country?
name, weight, ingredients list, nutritional panel, date markings, storage instructions, info must be bilingual. The exception to these rules are one-bite candies. Anything manufactured in Canada but destined for another country doesn’t necessarily have to follow these rules
glucose + fructose = ?
sucrose
glucose + galactose = ?
lactose
glucose + glucose = ?
maltose
glucose + fructose = ?
sucrose
glucose + galactose = ?
lactose
glucose + glucose = ?
maltose
