topic 5 Flashcards
Why is wax added to fruits and veggies?
to restore natural wax of food that is taken off when washed before shipped. This wax is naturally present and prevents the food from drying out. So, the added wax just comes to replace it.
What is morpholine? Is it carcinogenic?
Added to wax where in body it can become chemical nitroso-morpholine. High amounts in animals can become carcinogenic but it is not a really a concern to us because our consumption is v small
Wine was fortified with….
Lead acetate to make it sweeter
Vegetables had something added to it to make them look greener and more appealing?
Copper salts
What is Plaster of Paris and why was it added to bread? What else was added?
(CaSO4) added to it to make flour last more and white powder was added which contained arsenic oxide!
bitter almonds, lima beans, fruit seeds, cassava roots have naturally occurring…
cyanide, so, they need to be properly prepared, otherwise poisoning can occur
Sassafras is used as….it contains…
Sassafras leaves were used as cleansing agents, but they contain safrole which is a potential carcinogen. It was banned due to this.
why do we need chemicals in our food?
to replenish the chemicals in our bodies
True or false: Salt content is greater in processed foods than in unprocessed foods. Processed cheese has 2x the amount of Na than unprocessed cheese.
True
Where does the term salary come from and how is it related to salt?
Term “salary” comes from “salarium”, the Latin term for salt. It is believed that Roman’s salaries were used to buy salt, because it was so important.
Salts substitutes exist, but why aren’t they widely used?
taste of salt is very difficult to replicate. NoSalt (KCl) doesn’t really taste by salt.
What is MSG? How does it work?
chemical additive, discovered from fact that Japanese used seaweed as a condiment as it tasted good
brings out umami taste
- Increased salivation: extracts flavourful additive components of food
- Increased sensitivity: makes food taste better
What does MSG cause? Are they allergic to it?
Chinese Restaurant Syndrome or Kwok’s Disease, similar to heart attack symptoms. NOT allergic to it, but causes adverse reactions.
Where can you find a precursor to MSG and what is it called?
cheese, mushrooms, eggs, tomatoes, it is called glutamic acid. Becomes MSG when in contact w salt.
MSG is made…
produced in lab from bacteria-fed molasses which then converts into glutamic acid. Subsequently treated with NaOH to produce MSG.
How many food additives are taken in per year? How many chemicals is this? Is it a lot?
Food additives taken in per year is ~1lb/yr or ~500g. This represents ~2000 chemicals. The amount of these chemicals is therefore extremely small.
Basic tastes (6)
sour, sweet, salty, bitter, umami, kokumi
what is kokumi?
Kokumi: full taste, cheese especially. Pinot noir from Oregon supposedly has this taste.
Does butterball brand turkey actually have butter?
No, it has margarine, so + saturated than butter.
How does salt as a preservative?
Through osmosis: movement of a solvent, through a semi-permeable membrane, from a region of low solute concentration to a region of high solute concentration. High salt allows to dry out food AND bacteria, so they die and food is preserved
What did Louis Pasteur do?
put to rest the concept of “spontaneous generation” because some believe that organisms could be created from nothing. He showed that microorganisms coming from outside would cause problems (l’experience du col de cygne, if microorganisms were not allowed in, nothing would develop).
What is l’experience du col de cygne?
An experiment that shows that if microorganisms are not allowed in an environment, nothing will form.
True or false: sugar is not a preservative as it cannot function with osmosis.
False, sugar also works as a preservative, also works through osmosis.
Ketchup technically has no added preservatives, but what does it have that acts as one?
High sugar content (30%)
What are chemical additives used for?
Preservation, taste, color, preventing food poisoning
Name 3 preservatives
Sugar, salt, smoke (it dehydrates (eg. fish) and chemicals prevent growth of bacteria)
Why is red herring red?
Because smoking it develops a red colour
True or false: E.Coli only exists in meat
False, it can also be found in produce due to runoff from manure
E.Coli is a bacteria that grows…
inside the stomach of cattle.
Incidence of food poisoning is higher due to many reasons, but namely 2:
- industrial farming: animals and cattle and chicken grow up in crowded conditions making it more prone for the development of infection.
- Use of antibiotics in animal feed: in U.S. 70% of antibiotics are used in animal feed, this is because they are used as prevention for infection spreading due to crowded conditions and because animals will grow faster (less food competition in their guts). Concern: chicken or cattle may develop bacteria that are resistant to antibiotics. So, when you consume them, the bacteria make you ill and survives due to resistance to antibiotic.
Sodium phosphate
retains moisture and gives texture
sodium tripolyphosphate
(Na3PO4): in Kraft dinner and cleaning agent (ties in with Ca and makes water less hard)
what is the difference between flavour and artificial flavour?
Flavour: comes from foods naturally
Artificial flavour: comes from synthetic sources
What is the most added chemical to foods?
Artificial flavour
Vanillin is found in…
artificial vanilla extract, in natural vanilla, imitation cherry flavour
True or False: artificial smoke flavour is worse than broiling meat
False, might be safer than broiling meat, produced by passing hickory smoke through a water solution so flavour is picked up and toxic chemicals left behind!
What is the most widely used foood colour in N.A. and mostly used in soft drinks? Why are some people concerned about it?
Caramel, Derived from plants but produces 4-methylimidazole which may be potential carcinogenic to animals.
Name the natural food colourings
Carotenoids (E160), Cochineal red (from insects)
Synthetic colours are also known as…
coal tar dyes
T or F: citrus red #2 was used to colour inside of oranges
False, used to colour skin to make it appear ripe
Food dyes have been associated with…
hyperactivity
Though food dyes are not as dangerous as people make them out to be, what is a good reason to limit their consumption?
- Major reason to not consume food dye would actually be that they are mainly food in foods with poor nutritional value. So maybe stay away from food with foods with certified food dyes.
only dye that must be indicated by name (because some people have adverse reactions to it)
Yellow #5 (Tartrazine)
Red dye #3 can cause cancer in humans if…
the quantity is high enougn, eg. 14 000 servinfs of fruit cocktails w maraschino cherries.
Why does are high dose animal studies not reflective human exposure and risk
Because we are not rats, and often need higher doses for it to affect us. Also, the presence of a chemical does not equate with the presence of risk.
When is a chemical considered a human carcinogen?
if it causes cancer in test animals and when people who are exposed to the chemical exhibit a higher cancer rate
True or false: there are + natural carcinogens than synthetic ones
True
How does water intoxication work?
Explained by osmosis: too much water causes dilution of solute outside brain cells, so water inside brain cells will migrate outside and tissue in brain will swell up and die☹
why is vitamin C added to hot dogs
To prevent conversion of nitrite to nitrosamines
why are nitrites added to food?
To prevent browning of meat, keeps pink colour
T or F: celery juice has naturally occurring nitrates/nitrites which is why it is added to meats.
True
Sodium nitrite is used as a preservative because…
it prevents brown colour and adds tangy taste
why do we add citric acid to food?
Citric acid is used to counteract effect of metal interaction with food (which causes oxidation). Structure acts as a claw which traps the metal ions aka is acts as a chelating agent or sequestrant!
Calcium disodium EDTA is…
a metal sequestrant
Sodium Bisulphite (Na2SO3)
acts as an antioxidant,
used as additive and prevents food from turning brown, though some people are allergic and has caused death
used in grapes to make them crunchy
BHA/BHT
prevent oxidation of fats (rancidity), found in cereals especially in the packaging to conserve freshness.
They trap free radicals (reactive species that promotes the oxidation of fat) as free radicals’ single electron will attach to hydrogen from the BHT and leave behind another free radical that is now much more stable, and no chain reaction will occur.
Calcium propanate
preservative used in bread, used in rye bread to prevent development of ergot
True or False: Ergot contains chemicals like LSD and people with poisoning hallucinated
True
Ergot poisoning is also called…
Saint-Anthony’s Fire
Propionic acid
a natural preservative formed by lactic acid
What is added to ice cream to prevent fm of ice crystals as it absorbs moisture
carboxymethylcellulose
What are non-nutritive sweeteners? What country consumes most of them?
Splenda, Equal, Sweet’n Low, give very small amount of calories. U.S. consumes half of all the non-nutritive sweeteners in the world!!!!
Saccharin
has a bitter aftertaste, so never by itself, not allowed as a food additive in Canada but yes in U.S. 800 cans of diet soda must be consumed for saccharin levels to cause cancer. Found in Sweet’n’Low in U.S.
True or false: Hazard = risk
False, Risk = hazard x exposure x susceptibility
Sorbitol
poly-alcohol used in diet products but sits in colon for v long bcz slowly metabolized and can cause explosive diarrhea, found in Trident gum
Xylitol
poly-alcohol, found in sugarless gum as it does not promote tooth decay as it does not provide food to bacteria in mouth and chewing it promotes salivation which in turn dilutes tooth-decay causing bacteria. Found in Trident gum. Excessive use may have laxative effects.
Cyclamate
saccharin-free sweetener, found in Twin sugar, discovered accidentally by Michael Sveda in 1937 as he was smoking in lab and realized cigarette had sweet taste as it laid next to a compound (cyclamate). Blended w saccharin to decrease bitterness of saccharin.
Sweet’N’Low
has cyclamate in Canada but not U.S., has saccharin in U.S. but not in Canada.
Aspartame
Mix of aspartic acid and phenylalanine (so warning for people with penulketonuria (PKU)). Discovered accidentally Aspartame is the methyl ester of this compound. When aspartame is metabolized and broken down it releases methanol and safety issues are due to it (it is toxic). ADI = 40mg/kg
NutraSweet
Name for aspartame by Monsanto company
Aspartame is not recommended to be used in baked products, why?
It is not heat stable, so only used in diet drink and cold products. When heated, the links between the aspartic acid, phenylalanine, and methanol are broken, causing methanol to be released and sweetness disappears. Methanol is toxic, but not in amount in food
T or F: Aspartame can cause brain tumors
F, there was an association between the 2 in female rats, but turns out the study was not properly conducted and association is not causation.
Sucralose (splenda)
heat stable, can be used in baked products, similar structure to sucrose as it is a chlorinated derivate of sucrose.
Accidental discovery at King’s College in Professor Leslie Hough’s lab where Shashikant Phadnis (grad student) was told to test the compound, but he misunderstood the word test for taste
It is no.1 sugar substitute ahead of aspartame. Found in diet drinks.
Stevia
natural sweetner derived from plant, additive since 2008, different forms depneding on what is added to the plant.
Truvia, developed by Coca-Cola, has Rebaudioside A (Erythritol, cellulose, artificial flavors). Pure Via, developed by PepsiCo had Rebaudioside A (dextrose, cellulose, artificial flavors).
Monk fruit
Natural, fruit, sweetener, 0 cal
Do artificial sweeteners actually help reduce caloric intake?
studies have shown that the people who use artificial sweeteners to cut calories compensate and use it as an excuse to take in more calories from other sources. From a metabolic point of view, these people develop a craving for sugar and consume it more. So it defeats the purpose. So no need to use artificial sweetener for most people (unless they need to for a medical condition)
What are high intensity sweeteners mostly used for (2).
- Soft drinks
- Oral hygiene products.
What sweeteners have similar chemical structures
Saccharine, cyclamate, and acesulfame-K
