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What component found in spices gives them their pungency?
What component found in spices gives them their pungency?
Cooking cabbage allows for the formation of isothiocyanates.
Cooking cabbage allows for the formation of isothiocyanates.
False
What happens to glucosinolates when plant tissue is chopped?
What happens to glucosinolates when plant tissue is chopped?
They bind to the enzyme myrosinase, resulting in the production of isothiocyanates.
Lemon juice is added to lower the pH and __________.
Lemon juice is added to lower the pH and __________.
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Match the following components to their properties:
Match the following components to their properties:
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Which of the following is NOT one of the four primary taste sensations?
Which of the following is NOT one of the four primary taste sensations?
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Taste and odor are combined to define flavor.
Taste and odor are combined to define flavor.
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What do we call the property of volatile substances detected by the olfactory system?
What do we call the property of volatile substances detected by the olfactory system?
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Taste substances are usually __________ and non-volatile.
Taste substances are usually __________ and non-volatile.
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Match the following taste sensations with their descriptions:
Match the following taste sensations with their descriptions:
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What is the main drawback of Aspartame?
What is the main drawback of Aspartame?
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Neohesperidine Dihydrochalcone is known for its sweetness, being 1500-1800 times sweeter than sucrose.
Neohesperidine Dihydrochalcone is known for its sweetness, being 1500-1800 times sweeter than sucrose.
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What natural source is Glycyrrhizin derived from?
What natural source is Glycyrrhizin derived from?
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Aspartame poses health concerns specifically for __________ patients.
Aspartame poses health concerns specifically for __________ patients.
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Match the following artificial sweeteners with their characteristics:
Match the following artificial sweeteners with their characteristics:
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Which of the following statements about Sucralose is correct?
Which of the following statements about Sucralose is correct?
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Stevioside is extracted from the roots of a tree native to South America.
Stevioside is extracted from the roots of a tree native to South America.
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What sweetness factor of Alitame is noted in the content?
What sweetness factor of Alitame is noted in the content?
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What is the dominant component of peppermint oil that is known for its cooling properties?
What is the dominant component of peppermint oil that is known for its cooling properties?
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Monosodium glutamate (MSG) has a strong taste on its own.
Monosodium glutamate (MSG) has a strong taste on its own.
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What is the effect of adding MSG to food that contains modest amounts of IMP?
What is the effect of adding MSG to food that contains modest amounts of IMP?
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The breakdown product of AMP that accumulates as ATP is utilized in the muscle post-mortem is called _____ .
The breakdown product of AMP that accumulates as ATP is utilized in the muscle post-mortem is called _____ .
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Which compound is primarily derived from protein breakdown during the aging process of meat?
Which compound is primarily derived from protein breakdown during the aging process of meat?
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Match the following compounds with their related effects in meat flavor:
Match the following compounds with their related effects in meat flavor:
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The sweetness of meat can be attributed primarily to its odor.
The sweetness of meat can be attributed primarily to its odor.
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The three major groups of compounds contributing to the flavor of meat are MSG, IMP, and _____ .
The three major groups of compounds contributing to the flavor of meat are MSG, IMP, and _____ .
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What is the sweetness intensity of Thaumatin compared to sugar?
What is the sweetness intensity of Thaumatin compared to sugar?
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Bitterness is predominantly sensed when the ionic diameter is greater than 0.658 nm.
Bitterness is predominantly sensed when the ionic diameter is greater than 0.658 nm.
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Name one phenolic substance that contributes to bitterness in fruit juices.
Name one phenolic substance that contributes to bitterness in fruit juices.
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Saltiness is easily detected on the ______ of the tongue.
Saltiness is easily detected on the ______ of the tongue.
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Who first used quinine as the treatment for malaria?
Who first used quinine as the treatment for malaria?
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Match the following acids with their common sources:
Match the following acids with their common sources:
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Astringency is regarded as a taste sensation.
Astringency is regarded as a taste sensation.
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What kind of substances are tannins and what nutritional effect do they have?
What kind of substances are tannins and what nutritional effect do they have?
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The bitter taste of ___________ is an important characteristic of beer.
The bitter taste of ___________ is an important characteristic of beer.
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Which of the following compounds is NOT considered a bittering agent?
Which of the following compounds is NOT considered a bittering agent?
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What is the primary compound associated with the flavor of onions when they are cut?
What is the primary compound associated with the flavor of onions when they are cut?
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Synthetic flavorings are made only from natural ingredients.
Synthetic flavorings are made only from natural ingredients.
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What are terpenoids primarily associated with in regards to fruit?
What are terpenoids primarily associated with in regards to fruit?
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The enzyme responsible for off-flavors in vegetables when damaged is called _______.
The enzyme responsible for off-flavors in vegetables when damaged is called _______.
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Which compound found in garlic is known for its health benefits and can lower blood cholesterol levels?
Which compound found in garlic is known for its health benefits and can lower blood cholesterol levels?
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Blanching vegetables can activate the enzyme lipoxygenase.
Blanching vegetables can activate the enzyme lipoxygenase.
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Name one type of component that contributes to the aroma of fruits.
Name one type of component that contributes to the aroma of fruits.
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In many fruits, the main volatile components responsible for flavor are _______ and _______.
In many fruits, the main volatile components responsible for flavor are _______ and _______.
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Match the following food items with their associated flavoring compounds:
Match the following food items with their associated flavoring compounds:
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What effect does cutting garlic have on its flavor?
What effect does cutting garlic have on its flavor?
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What is formed when nitrite oxidizes the iron of muscle myoglobin?
What is formed when nitrite oxidizes the iron of muscle myoglobin?
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Smoke is used primarily for its preservative effects on meat and fish.
Smoke is used primarily for its preservative effects on meat and fish.
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What red/pink pigment is formed in uncooked bacon and ham?
What red/pink pigment is formed in uncooked bacon and ham?
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The gas phase of wood smoke contains the antimicrobial compound __________.
The gas phase of wood smoke contains the antimicrobial compound __________.
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Match the following compounds to their uses or characteristics:
Match the following compounds to their uses or characteristics:
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What is the primary yeast used in fermentation that can suppress undesirable yeast and bacteria?
What is the primary yeast used in fermentation that can suppress undesirable yeast and bacteria?
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High levels of sulfur dioxide (SO2) have no reported allergic responses in asthmatics.
High levels of sulfur dioxide (SO2) have no reported allergic responses in asthmatics.
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What vitamin is lost when vegetables are stored in sulfite solutions?
What vitamin is lost when vegetables are stored in sulfite solutions?
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Sodium benzoate is commonly used as a preservative for its __________ solubility compared to benzoic acid.
Sodium benzoate is commonly used as a preservative for its __________ solubility compared to benzoic acid.
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Match the following organic acids with their primary uses:
Match the following organic acids with their primary uses:
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What is the primary purpose of using preservatives in food?
What is the primary purpose of using preservatives in food?
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Sodium chloride is commonly used today as a standalone preservative for most meats.
Sodium chloride is commonly used today as a standalone preservative for most meats.
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What chemical is added to curing salts to help reduce nitrosamine formation?
What chemical is added to curing salts to help reduce nitrosamine formation?
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The red/pink color in preserved meat is a result of the addition of __________.
The red/pink color in preserved meat is a result of the addition of __________.
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Match the following antimicrobial agents with their functions:
Match the following antimicrobial agents with their functions:
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What happens to nutrients when heat-processing methods are used to obtain sterility?
What happens to nutrients when heat-processing methods are used to obtain sterility?
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Microorganisms can thrive in high pH and temperature environments.
Microorganisms can thrive in high pH and temperature environments.
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Name one of the major reasons why it is unusual to use a single antimicrobial procedure for food preservation.
Name one of the major reasons why it is unusual to use a single antimicrobial procedure for food preservation.
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Study Notes
Flavour Chemistry
- Nutritionists often focus on the nutritional value of food, but flavour and appearance are more important to consumers.
- Taste and odour are collectively known as flavour.
- Taste is related to the perception of dissolved liquids, solids, or gases in the mouth.
- Odour, or aroma, is triggered by volatile substances detected by the olfactory system.
Difficulties in Investigating Flavour
- There aren't any physical or chemical probes for detecting flavour.
- Trained taste panels or experienced tasters are essential.
- Most food flavours depend on a combination of substances, not a single molecule.
- Even when the components of a flavour are accurately identified and reproduced, the original flavour cannot be completely replicated. This is because small amounts of components can have a large effect on the final flavour.
Taste
- Taste substances are mostly water-soluble and non-volatile.
- The four primary tastes are sweet, salty, sour, and bitter.
- Umami is a fifth taste sensation and is described as savoury and delicious.
Sweetness
- Sweetness has been extensively studied, particularly the characteristics of sugars.
- Sucrose is the reference sugar for measuring sweetness relative to other sugars.
- Most sugars are less sweet than sucrose.
- Sugar alcohols are obtained by reducing the carbonyl group from their parent sugars, for example, isomalt is made by a bacterium.
- Sugar alcohols are a little less sweet than sucrose.
Artificial Non-Sugar Sweeteners
- Different artificial sweeteners have varying sweetness levels relative to sucrose. Some examples include, but are not limited to: aspartame, saccharin, acesulfame-k, sucralose, and alitame.
- Several of these are derived from existing materials and have advantages in terms of taste, stability, and cost
- Some have limitations or safety concerns (e.g., banned by some countries).
- Numerous artificial sweeteners and their characteristics are provided in a table, including sweetness, calories per gram, and brand names.
Common Artificial Sweeteners and Their Characteristics
- Table presents sweetness, calories per gram, brand names of the most common artificial sweeteners.
Other Flavouring Compounds
- Descriptions of varying flavours and entities, such as saccharin, sodium cyclamate, acesulfame K, aspartame (a popular alternative to sucrose), neohesperidine dihydrochalcone, sucralose, and alitame.
- Other plant-derived sugar substitutes (e.g., glycyrrhizin, stevioside, and thaumatin) are also described.
- The characteristics of each of these alternatives are given, including their sweetness level relative to sucrose.
Bitterness
- Metal halides are used to understand the structural criteria for bitterness.
- Bitter tastes occur if the ionic diameter is smaller than that of potassium bromide (0.658 nm).
- Different substances that elicit a bitter taste are listed and explained.
- Phenolic compounds like flavonoids, common in fruits, are sources of bitterness in fruit juices.
- Bitterness in beer is due to dried hops.
- Bitter substances in plants are used to protect them from animals.
- Alkaloids such as nicotine, caffeine, cocaine, and quinine, are bitter and used in various applications.
Saltiness
- Salt is often used to increase flavour and is naturally present in many foods.
- Sodium ions play a role in the perception of flavour. This is especially prominent when used to increase flavour.
- The perception of salt is affected by the size of the ions involved.
Sourness
- Sourness is primarily related to acidity.
- Sourness in food is due to organic acids, such as citric and malic acid.
Astringency
- Astringency is a sensation of dryness in the oral cavity, and is usually regarded as desirable in some foods.
- Astringency occurs due to the reaction of proteins with phenolic compounds.
- This reaction comes from molecules in tannins and is especially noticeable in red wines and teas.
Pungency
- Pungency describes "hotness" and can be found in spices and chilli peppers.
- Pungency is due to capsaicinoids, such as capsaicin and dihydrocapsaicin.
- Pungency exists in various foods such as cabbage, broccoli, mustards and radishes.
- Pungency is also due to the production of isothiocyanates when glucosinolates react with myrosinase enzymes.
Cooling
- Cooling sensations are associated with toothpaste and mouthwash.
- Menthol is a well-known cooling substance derived from the peppermint plant.
Meatiness/Umami
- The essential flavour of meat/umami is related to factors like MSG (monosodium glutamate) and IMP (inosine monophosphate), which act synergistically to produce taste.
- Other compounds also contribute to the flavor of meat, like dipeptides and amino acids produced during Maillard-type reactions and via degradation from fatty acids. Meat flavour is directly linked to the ageing process.
Odour
- While taste gives a broad assessment, odour provides detailed information about a food.
- The number of different odours that humans can detect is substantial and distinguishing them is difficult.
- The human sensory system's response to smells is much more sensitive than responses to taste.
Meat
- There are three key groups of compounds influencing meat flavour - MSG and IMP, amino acid dipeptides and compounds from Maillard reactions, and breakdown of fatty acids.
Fruit
- Fruit flavours arise from a blend of taste and odour.
- Sweetness, acidity, and astringency collectively contribute to the perception of fruit.
- Essential oils, aromatic compounds (such as aldehydes and ketones), contribute to fruit odour.
Vegetables
- Many vegetables get their flavour from the enzyme lipoxygenase.
- The enzyme reacts to give off-flavours, particularly when physically damaged.
- Blanching can be used to deactivate the enzyme and reduce undesirable flavour components.
Onion and Garlic
- Onions and garlic contain compounds that only yield flavour when physically damaged, for example, crushing or slicing.
- The pungent flavour in raw onions and garlic is related to the production of thiopropinonaldehyde S-oxide.
- Garlic health benefits include cholesterol-reducing effects, antimicrobial properties, and anticancer properties, which are due to compounds such as allicin.
Synthetic Flavorings
- Synthetic flavouring has increased in demand to match the quality of natural flavourings in a wide range of foods.
- "Natural" flavors are derived from essential oils from plants and fruit.
- Many synthetic flavorings are designed to match and replicate specific flavors without providing nutritional value beyond taste. Note that "natural" flavors can sometimes be synthetically produced.
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Description
Explore the fascinating world of flavour chemistry, where taste and odour converge to create unique culinary experiences. This quiz delves into the significance of flavour in food, the challenges of investigating it, and the primary tastes that define our sensory perceptions. Test your knowledge and enhance your understanding of how flavour influences consumer choices.
