FInal Exam Flashcards
Difference sorbate and benzoate explain
Sorbate, active in salt form, used to inhibit mold growth and benzoate, active in free acid form, used to inhibit bacterial growth.
melted or frozen ice cream sweeter
Melted will taste sweeter since the cold from the frozen ice cream will numb taste buds and lessen the sweetness sensation.
differences between lactic acid and lactose and if there’s a relationship
Lactic acid is made from the fermentation of sucrose, potato starch, etc. and is doesn’t originate from dairy products. Lactose is the sugar found in dairy products that breaks down into galactose and glucose. It is the least sweet natural sweetener. Lactic acid is often found in fermented products as well as many dairy products.
purpose of using acidulants and applications 4 uses and examples (2 questions)
- Enhance taste in desserts and confectionnaries. Subthresholds amount of sour compounds
decreases saltiness). Vinegar gives piquancy and aromatic flavors to pickles. - Inhibit enzymatic activity ex. Enzymatic browning
- Inhibit microbial growth. Vinegar is used as a preservative for pickles.
- Increase gelstrength in pectinbased jams and jellies
- Activate antioxidant activity ex. Fumaric acid in mushrooms and rice products.
- Used in processing of wine to have a stable product.
drinking cold water to relieve black pepper
The cold will numb the taste buds temporarily to cause relief. Water does not stay in the mouth very long though so the relief will be short.
air and water do they both have the same affect and enzymatic browning
They do not. Water will temporarily inhibit enzymatic browning by restricting the amount of oxygen that comes into contact with the food item. The barrier is not present in air therefore enzymatic browning will proceed more quickly.
L or D amino acid sweeter
Usually, D amino acids taste sweet and L amino acids taste bitter. There are some exceptions such as L Ala which tastes sweet and DAla which tastes bitter.
2 examples of texturizers, water binding agent, emulsifying, foaming agents
Texturizers: thickener/thixotropic agents (gums, pectin, starch, sugars, whey protein, CMC), and emulsifying agents (monodiglycerides, mustard powder and lecithin).
Water Binding agents: Humectants (phosphates, polyphosphates, glycerol), anticaking agents (silicates, cornstarch)
Emulsifying agents: mono and diglycerides, mustard powder, lecithin
Foaming agents: egg whites, milk powder
2 amino acids in alitame
Aspartate and alanine
triangle test: panel how to chose from each corner
False. You Have 3 products. Two are identical. Pick the odd one out.
explain difference and preference tests
Preference tests are useful for the development of new products. Subjects are asked to choose the product that they prefer due to the overall taste. Tests include paired comparison, hedonic test and ranking. Difference tests are used to identify differences between products. One can identify certain attributes to a food and see if an improvement should be made. The sensory quality can be assessed. These test include simple paired comparison, scheffe paired comparison, ranking, multiple comparison, due trio, and triangle test.
Why would you chose synthetic over natural components
Natural colors do not give as vibrant of a color, it is more susceptible to changes in heat and light so the color can vary, can add flavor to food since more must be used and is much more expensive.
glucose vs fructose why is fructose sweeter
Fructose is sweeter due to its 5 membered ring, vs the 6 membered ring of glucose.
difference between high fructose corn syrup and corn syrup
In high fructose corn syrup glucose isomerase is added to regular corn syrup in order to convert glucose in fructose. Since fructose has a higher relative sweetness than glucose, the final product, in the same amounts, is sweeter than corn syrup.
3 things bitter tasting: xylitol, naringin, .. (false)
False: alkaloids (caffeine, theobromine, quinine), glycosides (naringin, coniferin, sinigrin, hesperidin), and certain amino acids.
What imparts sour sensation
H+ions.
What is ADI
Acceptable Daily Intake. It is the highest amount of a compound (weight/kg of body weight) that has not caused any harmful effects in the experiment animal divided by 100.
How do we perceive taste
Taste perception comes from the tongue and the nose and is interpreted by the brain to result in the overall sensation. Taste, mouthfeel and odor/olfaction play a role.
3 groups of food additives
Food Colors, Incidental (pesticides, PCBs, asbestos, etc.), Intentional (Processing aids, quality enhancers and preservatives)
what is sweetness equivalent
Sweetness comparison with sucrose (given value of 1)
MSG and mannitol are they flavour enhancers
only MSG
2 factors that affect mouthfeel (or necessary for)
tactile sensation (astringency, texture, consistency), temperature and pain
sour taste: tartiric, sorbic and citric (T or F) are organic not inorganic
T organic
3 characteristic of flavor
taste, odor, mouthfeel
do quinones impart a bitter taste
yes
hedonic scale is it part of the ranking test t/f
t
3 purpose for adding food colorants
∙ offset color loss due to exposure to light, air, temperature extremes, moisture and storage conditions
∙ correct natural variations in color
∙ enhance colors that occur naturally
∙ provide color to colorless and “fun” foods
what makes something sour
H+ ions
what makes a molecule sweet
electronegative N and O
theobriomine and bitter taste
It is an alkaloid that is structurally similar to caffeine and often found with caffeine in certain plants such as cola nuts.
selection of sweetners
carcicogenicity, solubility, heat of solution, hygorscopicity
Cariogenicity
Plaqueformation. Food fermented by Strep. Mutans pyruvate>formic, acetic or lactic acid which erodes tooth enamel. Polyols are not fermented by these bacteria and therefore do not cause enamel erosion.
Hygroscopicity
Water uptake ability. High values= soggy product and harder to preserve.
Solubility
Solubility should ideally be similar to that of sugar. Changes in solubility can have an impact on onset of sweetness sensation, duration of sensation and mouthfeel.
Heat of Solution
Heat reabsorption. If is low there is a cooling effect. This effect is found in polyols which is desired for certain products such as mints, lozenges, tablets, etc.
Sweetness equivalent
Alternative sweetener should be sweeter or isosweet to sucrose. Sucrose is given a value of 1 in relative sweetness in order to compare it to other sugars.
Criteria for Food additives
Must be to consumer’s advantage, must not deceive consumer, and must be safe to use continuously
t/f
quinine and threobomine are alkaloids
t
t/f
Acetic acid is the main component of vinegar
t
t/f
Is multiple test also named hedonic scale
f
t/f
frozen ice cream sweeter than melt ice cream
f
t/f
Food flavor is determined by texture, astringency and consistency
f
t/f
Temperature affects mouthfeel
t
t/f
Air and immersion in water have the same effect on enzymatic browning
f
Which is sweeter between L and D form
D
t/f
Quinine, threobromine, narigin in alkaloids
F (Naringin is a glycoside naringenin is the aglycone and Drhamnoglucose is the sugar)
t/f
Tartaric, phosphoric, citric acid in acidulants
T (citric and tartaric acid are GRAS general purpose acidulants but
Threshold value
Minimum amount of a substance for the sensation to be felt by the individual. Subthesthold amount of comopounds can have an overall effect on taste though. Subthreshold amounts of salt can decrease sourness and vice versa, etc.
What causes astringency
Precipitation of proteins in the cheeks from saliva
the dry sensation in cheeks
What are the factors that affect mouthfeel
tactile sensation, pain, temperature
How do you detect mouthfeel
sensed by jaw teeth and mouth
How does temperature affect taste perception
It affect mouthfeel which is a factor that determines taste.
How do we perceive bitterness?
Organic and inorganic compounds
Comparison: Taste modification VS Taste inhibition
Gymnemic acid makes taste buds insensitive to sweet and bitter. Taste modification: temperature increases solubility. Miraculin from miracle fruit makes sour and bitter taste sweet. Subthreshold levels of salt decreases sour taste, acids enhance saltiness, sugars reduce saltiness and sweet and salty reduces bitter.
Xylitol is isosweet to
sucrose
Flavor inhibitor and flavor enhancer
Flavor inhibitor examples include subthreshold amount of salt which reduce sour taste. Flavor enhancer examples include acids that enhance taste of deserts and confectionaries. Includes nucleotides (IMP (fresh meat, fruits and vegetables) and GMP), MSG, Maltol.
t/f Xylitol is isosweet to other aspartame and lactose
F Xylitol is isosweet to sucrose. It is sweeter than lactose and less sweet than aspartame (200x sweeter than sucrose and xylitol).
t/f
Astringency is caused by sucralose
(false, it is tannins) F caused by precipitation of proteins in cheeks from saliva
Triangle evaluation
place three samples in each of the corner of the triangle
Maltitol and Aspartame
Maltitol is a polyol, second sweetest after xylitol therefore less sweet than sucrose. It is very expensive.
Aspartame is a dipeptide that, under heat, becomes aspartate, phenylalanine and methanol. Methanol, with O, becomes formaldehyde=crosslinking agent. Phenylalanine and aspartate can affect mood by affecting CNS. Phenylalanine is converted to Tyrosine by PAH but without enzyme it accumulates and causes brain damage.
It is 200x sweeter than sucrose.
Define texture and mouthfeel
Mouthfeel is how the food feels in the mouth and is sensed by
jaw, teeth and tongue. Texture is a component that determines mouthfeel.
t/f
Ranking test may be used to evaluate the way food feels in mouth
T We can ask individuals to
rank a product based on a certain mouthfeelrelated characteristic such as texture or consistency.
t/f
Threobromine, quinine and xylitol are bitter tasting compounds
(false cause xylitol is a sugar)
Additives of sulfites and acids to foods destroys “something” food components
Thiamin (vitamin B1)
