Food & The Senses

What are the three ways textual sound is conducted and detected when eating foods?

- Air conduction to the ear. - Bone conduction in the mandible. - Through soft tissue in the cheeks and tongue.

Provide an explanation of the physical change that results in the intensified bright green of blanched beans.

- Air is removed from the surface and the intercellular surfaces. - Chloroplasts swell and burst, producing a more uniform green through the cell.

When preparing a green salad care is taken to maintain fresh qualities of the produce. How does the consumer perceive freshness before and during eating the salad?

- Before: Visual appearance/colors. Smelling it to make sure it isn't spoiled. - During: Crispiness and crunchiness equals freshness. Taste and texture is satisfactory - not wilted.

What is the difference between a blended and unblended flavor?

- Blended means there is a merging of many different flavour notes into one blended flavour profile. They are smoother and richer than their unblended counterparts. - Unblended means we experience flavour notes one-by-one.

Identify two different ways by which plant based food digestibility is improved when cooked.

- Breaks down physical barriers such as thick skins or husks by softening the cellulose. - Bursts cells, also helped by cellulose softening, making cell contents more easily available for digestion or absorption.

What is a cartoon flavor? What is a white space flavor?

- Cartoon: A duplicated laboratory flavour that includes the key elements of a natural flavor but lacks the fine details. Only the key elements are needed to fool our senses! - White space: Man made by blending components to make a unique combination (Coca Cola).

Why aren't crackers an effective palate cleanser?

- Chewing introduces a sweet taste from the amylose (sugar) in the starch. - May leave food particles.

Although palate cleansers are ineffective, why might a chef still include them on a menu?

- Consumer feels like they are getting something extra adding to the occasion. - It gives the kitchen more time to prepare for the next course. - The mental effect of using one is a placebo. - Exposure time equals recovery time so the time between the first course and the second course gives your palate time to recover during the palate cleanser.

Wheels representing sensory profiles have been used for colour, smell, taste and flavour. Identify the advantages of using this system of flavour analysis for food and beverages.

- Creates consistency in flavor profiling and provides a common language. - Allows sensory evaluation panels to visually plot the profile of a product. - Helps quantify the qualitative.

Describe two different sounds made when eating and provide an example of a food for each sound where texture contributes to the sensory experience.

- Crispiness of chips (relates to how easily it fractures and the crumbliness of the product). - Crunchiness of raw carrots (relates to the hardness of the product and the force required to bite through, conveyed especially through bone conducted sound).

What kinds of sounds to crunchy, crispy, and crackly foods make?

- Crunchy foods generate low pitched sounds with a characteristic peak for air conducted sound. - Crackly foods generate low pitched sounds with a high level of bone conduction. - Crispy foods generate high pitched sounds with a high level of frequencies, especially for air conducted sound.

What are the 4 ways raw food coloration occurs? Give examples and brief explanations.

- Direct evolutionary forces: Colored fruits. The reflective character of ripe fruit arose from the co-evolution of predator vision. - Default coloration: Green leaves. Chlorophyll's molecular structure absorbs red and violet rays and reflects green light not used as energy in photosynthesis. - Coincidental coloration: Mammal flesh. Haemoglobin, an efficient respirator in blood, is coincidentally red. - Environmentally derived. Fish flesh. Colouration is determined by blood or melanin derivatives produced for skin colouration, or arise from the food chain (pink flesh derives from carotenoids contained in a diet rich in crustacean).

Language serves communication and social functions. What are 4 of them?

- Enables us to connect social, cultural and historical information that influences food, people, places, attitudes and ideas. - Enables gaining and sharing culinary skills and gastronomic knowledge. - Provides a greater understanding of sensory elements relevant to food and drink. - Enhances the pleasure of eating and drinking through a shared language.

Identify and briefly discuss two underlying factors influencing the flavour of cooked meat.

- Intrinsic factors: Natural characteristics of the meat such as: species differences, breeds within species, diet, meat composition, organs and tissues. - Processing methods: Ways the meat is changed/preserved/cooked such as: slaughtering, aging, cooking on the bone, method of cookery resulting in chemical reactions.

Identify the four functions acidulants play in food and beverage products.

- Lowers the pH which reduces the chance of bacteria growth - Modifies and enhances flavor - Provides sourness - Assists in the gelling of pectin

Cooking has changed our sensory world. Identify two reactions that have introduced novel flavour molecules.

- Maillard Reaction: Occurs during cooking and adds flavour. Carbohydrates and amino acids combine to produce a wide array of tastes and aromas. Reaction products from any one amino acid/sugar pair are temperature dependant and influenced by environmental factors. Each type of food has a very distinctive set of flavour compounds that may form. - Caramelization: The thermal degradation of sugars leading to formation of caramel aroma and brown-coloured products. As the sugar breaks down it forms more complex volatile compounds that contribute to richer characteristic caramel flavour.

What are the methods of cookery categories?

- Moist heat: Use a liquid cooking medium that transfers heat to the food, and cooks the food by convection. - Dry heat: No liquid cooking medium. Heat is transferred by conduction, convection or radiation.

Identify and describe two acoustic techniques used to assess the perception of sounds contributing to sensations of food crunchiness. What is an acoustic technique?

- Play pre-recorded bite and chew sounds to subjects for evaluation of their properties (auditory technique). - Ask subjects to bite or chew the food themselves and evaluate sounds produced (oral technique). An acoustic technique is a perception of air-conducted sounds that establishes their contribution to the sensations of crispness and crunchiness.

How might the questions and ingredient cues have assisted in the aroma challenge?

- Provided context and direct comparisons - Prompted/provoked our experiences - Multi choice options = limited choices - Grouping narrowed down the options

What is the difference between sensation and sensory experience?

- Sensation: The disruption of receptors on the body's surface by some form of energy. The vast majority of sensations remain outside awareness. - Sensory experience: Conscious awareness of sensation.

Identify and explain four characteristics of a degustation menu that either contribute to, or help overcome sensory adaption.

- Several small portions/short periods of exposure - Time between courses for recovery - Palate cleanser (placebo effect) - Different colors, textures, tastes/no repeated flavor profiles

What effect does sugar have on pH? How can it be tested? What effect does sugar have on the perception of sourness, and salt have on the perception of bitterness?

- Sugar is a molecular solid that does not effect pH - it just masks the acidity and balances it out. This could be tested by adding sugar to 50/50 lemonade water mixtures and using a pH probe tester to see that it always stays the same despite the amount of sugar. - Sugar masks perceptions of sour. Salt masks perceptions of bitter (quinine in tonic).

Cinnamon's familiar aroma is described as spicy, warm, musky or woody - and 'sweet' when it does not really taste sweet. Explain, from a 'top-down' cognitive perspective, how this error arises. Describe a simple experiment that proves that cinnamon does not actually taste sweet.

- The stimulus associates cinnamon with sugar because many dishes include both together. People use cognitive input to describe it rather than information from the sensory experience. Rather than evaluating the cinnamon itself, people make the error that cinnamon is sweet because it often is tasted at the same time as sweetness, for example in doughnuts. - Experiment: Provide a taste of cinnamon to a person wearing a blindfold and nose-clip so that they cannot see or smell - they will not be able to identify the product or taste any sweetness.

Reading aroma-related words is enough to activate olfactory regions of the brain. Identify four commercial applications relating to food where well-developed sensory language skills could be useful.

- Writing menus - Advertising - Publication (literature/reviews/blogs) - Sensory evaluation (descriptive analysis)

The sniff is part of the olfactory process. To pay attention to an odorant we capture it with a sniff. Provide two sniffing techniques that could improve smelling ability.

1) A short inhalation with a high rate of air flow. Quick and strong. 2) A single sniff rather than subsequent sniffs - do not continue to smell or you will adapt to it and it will fade into the background (first sniff is the best).

Most people have essentially the same physical structures to detect odour as a professional wine taster however a number of factors contribute to olfactory talent of the expert. Identify two factors that contribute to the olfactory talent of the professional.

1) Olfactory sensitivity - Ability to discriminate and identify odors. Constant honing of perceptual skills may change how an expert's brain responds to odorants. 2) Language - Ability to express smells using words. Develop specialized cognitive skills that make better use of the sensory information and avoid verbal overshadowing effects. (They make notes when tasting).

What are the basic properties of odorants?

1. Intensity 2. Quality 3. Character 4. Frequency 5. Duration

Provide 6 reasons why we have developed a liking for crispy food.

1. Quality measure of freshness. 2. For our ancestors (and people of many cultures today), crispy insects was an attractive meal. 3. A liking for raw crispy veggies is useful if the need arises to survive on 'fallback foods'. 4. Contributes to palatability of cooked foods. 5. Adds to the sensory mix staving off boredom and 'adaption'. 6. In the modern food environment, commercially produced crispy food is strongly promoted, and some are 'bad' which adds to a guilty pleasure.

Name the stages of texture profiling.

1. Seeing texture 2. Surface contact 3. Partial compression 4. First bite 5. During chewing 6. Residual effects

What is flavor?

A complex combination of the olfactory, gustatory and trigeminal sensations perceived during tasting.

What is sensory adaption?

A decrease in the sensitivity or responsiveness of an observer as a function of constant stimulation.

If a recipe requires a pinch of salt, do not omit it. Why? Provide an example to illustrate your answer.

A little salt goes a long way in a recipe. It helps to bring out other flavours from the ingredients, such as sweetness. For example, many chocolate chip cookie recipes call for a pinch of salt. This is because the salt will enhance the sweetness of the chocolate/sugar in the batch and improve the overall taste of the cookies. A pinch of salt is usually included in a recipe in order to heighten flavours, so you should not omit it.

What is olfactory adaption?

A new odour smells strong when we first experience it, however the longer we are exposed to it the more it fades into the background to the point where the smell may become undetectable. This adaption is only a temporary change; the extent of it depends on the extent of smelling being done. The longer you are exposed to an odour, the more you adapt to it. But when the odour source is removed the nose gradually regains it's sensitivity. Recovery time mirrors that of adaption. Olfactory adaption constantly recalibrates our noses to background conditions, freeing our attention for the next new scent.

Define 'profile.'

A view or description based on analysis of information summarizing or describing a set of distinctive or defining characteristics/features.

Old eggs are more alkaline. What impact is this likely to have on their sensory characteristics when hard-boiled?

Alkaline conditions favor stripping sulphur atoms from proteins unfolded by heat. This influences the yolk to develop a green-grey discoloration, and it grows smelly and off-tasting.

What is another use for salt in the kitchen?

Another use for salt in the kitchen is preservation. It's great for preserving food because bacteria have trouble growing in a salt-rich environment. Foods that are preserved well with salt are things such as cured salmon, dried meat, etc. It protects against growing bacteria, mold and spoiling because it dries the food out.

What is associational symbolism? What is acculturated symbolism?

Associational - Based on personal experiences that arises from upbringing and education. Acculturated - Refers to food preferences that are influenced by culture, tradition, celebration, religion and folklore.

Provide 2 recommendations relating to the ideal water to make tea.

Avoid over boiled water. Use filtered water that is not chlorinated.

What effect does background noise unrelated to food have on the gustatory food properties of saltiness and sweetness? What are other effects of background noise?

Background noise reduces the perceived taste of saltiness and sweetness. It also effects auditory food properties such as crunchiness and food liking.

What is 'bottom up' sensory cognition?

Based on your senses alone and not influenced by expectations. It's the concrete information gained from the world around you. It's the stimulus from the environment that our brain detects and interprets.

What are two fat solubles found in tomatoes?

Beta-carotene and lycopene - both carotenoids. Cooking tomatoes makes them more readily available. Increases digestibility, increases nutrient density and releases nutrients.

What is the natural pigment/colorant found in carrots and why was the butter with the colorant a brighter yellow, even after it was washed?

Beta-carotene is the natural pigment. The butter with beta-carotene in it stayed yellow due to the high fat content in the cream and because beta-carotene is fat soluble. This means the yellow beta-carotene attached to the fat and stayed stuck to it even after it was washed.

Why is flavor is often called the "sixth sense"?

Different areas of the brain are activated for the perception of taste and for smell, but when perceived together an additional area lights up as well.

What is an innovative sugar product that uses world first technology?

Chelsea LoGiCane™ Sugar uses world first technology to develop a sugar with a naturally low GI. All-natural molasses extract is sprayed onto raw sugar to increase resistance to digestion resulting in a slower release of energy, which can help to curb hunger cravings. All natural, same sweet taste and functionality as ordinary sugar, added benefit of a low GI.

Associated aromas may contribute to the perception of sweetness. Provide one example of a spice that can do this and explain why.

Cinnamon's familiar aroma is described as spicy, warm, musky or woody - and sweet. But it is not really sweet; this confusion between the senses is the result of associating cinnamon with sweet treats that it is included in such as apple pie, sticky buns, etc. When tasting cinnamon these sweet combinations are remembered.

What is cooking? Why do people cook?

Cooking is applying heat to improve nutritional qualities of food. It's a cultural transformation of raw food. It's also a biological requirement for human survival (evolutionary benefit of adapting to cooked food is less energy required for digestion).

Describe the cellular structure and mechanism of sound production of dry crispy foods. Provide an example of a dry crispy food.

Dry crispy foods (potato chips) air filled cavities are surrounded by brittle walls. When broken with a bite, the remaining walls and fragments snap back to their original shape. This movement sets off vibrations, which generate a sound pressure wave. Crushing/breaking the cavity wall is what creates the sound.

Why are small bites/tapas appealing with reference to odour adaption?

Flavor intense, small portions reduce exposure to any odour stimulant and hence reduces the extent of odour adaption and sensory fatigue. Reduced exposure means the time course of recovery is also quicker. Time between courses also aids recovery. As adaption is odour-specific, provided the next course offers different flavours, attention would move on to the next new scent.

What is the style of cuisine that has developed that brings together ethnic influences from around the world?

Fusion cuisine - A pioneer blend of eastern and western style cuisines.

What creates the perception of umami?

Glutamate helps create umami perception. Measured by free glutamates, not bound. Isolated and patented monosodium glutamate (MSG). Many foods naturally impart an umami taste. Cooking liberates/forms umami taste by deconstructing food. Tastes and aromas associated with umami are: meaty, savoury, rounded out, heightened flavor, richness, fermented, cured, aged.

A Sauvignon Blanc is comparable to what type of tea? Identify what food this tea compliments and provide an example.

Green tea. The lighter structure compliments light foods that have been poached or steamed. Works well with fish, poultry, salad and light Asian dishes.

What tastes are hedonic and aversive?

Hedonic: - Sweet indicates a high carbohydrate content, which means a high nutrient value. Good to eat (ripe fruit). - Salty food is important for our electrolyte balance. - Umami reflects high protein levels. Aversive: - Bitter has a warning function that protects us from poisons substances. - Sour indicates spoilage or not ready to eat (unripe fruit). But can add flavour, aid preservation, and is good for digestion.

Most people in the developed world consume excess salt, resulting in what health problems?

High blood pressure. Obesity. Heart disease.

What is the effect of hunger?

Hunger is the physical sensation of desiring food - it can make food savour better. The more you body needs something, the more pleasant it is to ingest it. When hungry, your body produces ghrelin, the hunger hormone, which makes you sniff more, getting more flavour from your food.

Explain how retro-nasal smell contributes to flavour.

It arises from inside the mouth therefore is always accompanied by other senses; mainly taste and touch. Chewing/warmth of mouth releases smell molecules/vapors from food to be carried to the nasal passages to stimulate the smell receptors. After the nasal passages, they reach the Olfactory Bulb where they are translated as flavor by the brain. This gives the perception that the aroma you are smelling is a flavor they are tasting. Flavour appears to occur in the mouth, where the food is, so many people tend to think flavor is the same as taste - but it is actually a combination of both smell and taste! There are only 5 primary tastes yet there are many more flavors due to the contribution of smell.

Explain why consumers may have developed a preference for eggs with brown egg shells and darker coloured yolks.

It's what they have been brought up to consider appropriate/what they're used to seeing in terms of commercially sold eggs. Brown eggs with darker yolks tend to be considered more "natural" than white eggs with light yolks, therefore the preference for them is founded on actual or perceived product quality and association with good health.

How can we classify the senses by the nature of the stimulus?

Light: Sight (vision) Mechanical: Touch and hearing Chemical: Sensed as tastes and smells OR 'internally' with blood glucose

How do chewing sounds influence judgments of food crispiness?

Loudness of sounds relate to a consumer's perception of food crispness. However, oral tactile sensations may also be used to discriminate crispness. People can still determine crispiness without sound.

Explain how and why dry crisp foods, such as cornflakes, should be appropriately stored and provide one reason why maintaining crispness it is important in an assessment of the food's quality

Maintaining crispiness is important in assessing freshness. Dry crispy foods need to be appropriately stored so the brittle walls do not become stale. Store dry crispiness foods in an air-tight container in a dry area. Important for actual or perceived freshness.

What is mouth-sense and what do the sensory pathways convey?

Mouth-sense is enabled by the somatosensory system (mechanism of the sense of touch), which includes a range of sensory pathways that convey: - Touch (tactile, texture, consistency) - Pressure - Temperature (hot or cold) - Pain (burning) - Heat effect and cooling effect - Taste sensations, energy taste, etc.

What is an artificial flavor substance?

Not identified in a natural product intended for human consumption, whether or not the product is processed. Typically produced by fractional distillation and additional chemical manipulation of naturally sourced chemicals. Although they are chemically different, in sensory characteristics they are the same as natural ones.

What is a nature-identical flavouring substance?

Obtained by synthesis or isolated through chemical processes. They are man-made, but are chemically and organoleptically identical to flavouring substances naturally present in products intended for human consumption.

What is a natural flavoring substance?

Obtained from raw plant or animal materials, by physical, microbiological or enzymatic processes. They can be used in their natural state or processed for human consumption.

A relatively high number of papillae on the tongue containing taste buds can indicate a person's genetic disposition for tasting bitter and spicy food. What genetic test can also indicate if a person is a super-taster?

PTC test or PROP test. Tasting PTC is a dominant trait. Your genes influence whether a food tastes bitter to you. We have different receptors for different types of bitter to provide broad awareness of dangerous substances, instantly evaluating taste as a 'spit or swallow' response. Babies have a strong negative response to bitter tastes.

What are 3 physiological responses to food aroma?

Salivation, the pancreas releases insulin, and the secretion of digestive juices.

What is the order of the sensory experience?

Stimulus Sensory organs (receptors) Sensation Perception (interpretation) Recognition

Perception

The "added value" that the organized brain gives to raw sensory data. It goes beyond sensations and involves memory, experiences and higher-level processing.

Explain why there is greater use of spices among cultures in the equatorial regions of the world.

The antimicrobial hypothesis - The protective quality of the plants grown in hot climates protect us from bacterial growth. Warmer climates are more likely to have bacteria growth, but spices grown in equatorial regions may counteract that growth.

Food colour may be changed, enhanced or lost during cooking. With this in mind, what cooking instructions would you provide to a commi chef preparing beans for a Salad Niçoise?

The beans should be blanched yet not overcooked to get a bright green color to stimulate the sense of sight. The beans should be a fresh, undamaged product.

In the tutorial exercise fresh lemon juice was heated and later consumed when cold. This changed the olfactory character of the juice. Explain how this occurred.

The juice that was boiled no longer contained all the aroma compounds that regular fresh juice contains. The heat destroys the aromatic top notes because boiling the juice liberated the lighter compounds and they evaporated off into the air. This is similar to what happens when juice is pasteurized because volatile molecules are the ones that become airborne and, when heated, they release even more.

What is haptic perception?

The process of recognising objects through touch

Why do people associate odours with past experiences and involuntarily assess the odour as likable, disagreeable or indifferent?

The sense of smell is first processed in the limbic lobe, which is also the seat of emotional impulses. This close connection may explain why a scent might get tied to vivid memories in your brain, and then come flooding back when you're exposed to that particular odor trigger. All other senses are processed in the thalamus first, but not scent. It travels through the region of your brain that controls memory/emotion before reaching the thalamus. With scent, there is extra processing before you even have a conscious awareness of it.

When carving and plating roast chicken it is recommended that the meat is portioned according to the resultant colour of two basic types of muscle fibre. Explain how this could be achieved.

White meat muscle fiber is found in carving the chicken breast. Dark meat muscle fiber is found in carving the chicken thighs and legs.

Natural salts include different minerals and traces elements depending on their source that give a complex and unique flavor. What structural differences affect perceived saltiness? Suggest how many natural salts are best used in a dish.

The size of salt crystals influences perceived saltiness. Larger crystals take up more surface area on your tongue therefore it takes longer for them to dissolve in your mouth, so it seems saltier because there is a lag time. Appears to keep the saltiness in your mouth longer. With fine crystals, saltiness comes quickly but also dissolves quickly. The taste doesn't last in your mouth as long. Larger, fancy crystals can be used as finishing because they have an appealing appearance. Fine crystals can be used while cooking to be dissolved into the dish just for taste/flavor.

Describe an experiment proving that the widely accepted traditional tongue taste map showing distinct regional sensitivity to bitter, sour, salty and sweet is an over simplification that assumed areas of lower sensitivity are areas of no sensitivity.

The vinegar test proves that the sour sensation isn't just isolated to one spot on the tongue because you can feel it all over tongue on the multiple areas we tested for each taste. Take a cotton swab dipped in vinegar and put the swab on the different parts of your tongue, and use water as a palate cleanser in between each. Sourness can be sensed in every spot, with a slightly heightened sensitivity to the expected sour section.

How does 'top down' sensory cognition of colour influence perception and judgements about food?

Top down is your cognitive input based on previous experiences/previously activated pathways in the brain. The color of food influences our perceptions of it due to our prior knowledge, associations, memories, and expectations. For example, the carbonated drink activity.

Asian cuisine is based on traditional umami rich ingredients. Describe how the umami taste rounds out and heightens food flavours and provide one example of a product with a strong umami flavour used in one Eastern cuisine.

Umami taste rounds out flavours due to the presence of glutamate that contributes savouriness, richness, meatiness, etc. Many foods naturally impart an umami taste when they are cooked. When umami substances are formed or liberated it acts on other tastes such as enhancing saltiness. Umami is a taste that contributes to flavor profile. Eastern cuisine - Japanese Product - Kombu (rich source of glutamate) Dish - Miso soup

What is a palate cleanser?

Used to remove lingering flavours from the mouth so that the next course may be enjoyed with a fresh perspective. Minimizes flavour carryover.

Describe the cellular structure and mechanism of sound production of wet crispy foods. Provide an example of a wet crispy food.

Wet crispy foods (nashi pears) contain fluid under turgor pressure within their cells. Balancing this outward force of turgor is inward force produced by cell wall strength and elasticity. When a turgid cell is ruptured as you bite, a sound is produced as its contents expand very rapidly. Stronger cell walls can withstand more turgor pressure and therefore produce a louder sound upon breaking.

Food preferences may be founded on actual or perceived product quality. Why have synthetic yellow colorants often been used in cake products and explain what type of 'symbolism' does this represent?

Yellow colorants have often been used in cake products to give the impression of a greater yolk content. People associate greater yolk content with healthiness or more expensive ingredients. This is associational symbolism.