Factors Affecting Food Choice & Sensory Evaluation
How We Perceive Food: Taste and Smell
Every time you eat, several senses work simultaneously to build your impression of the food. Taste receptors are clustered in taste buds, most of which sit on the tiny bumps (papillae) on the surface of the tongue. These receptors detect five basic tastes: sweet, salty, sour, bitter and umami (savoury). Each taste is a chemical signal — sugar molecules binding to sweet receptors, hydrogen ions from acids triggering sour receptors, glutamate compounds activating umami receptors.
Smell, however, carries more sensory information than taste alone. The olfactory system detects hundreds of volatile aroma compounds that drift up from food into the nasal passage — both directly through the nostrils (orthonasal) and retronasally when food is in the mouth. This is why food tastes flat when you have a blocked nose: the taste receptors still fire, but the olfactory contribution is lost. Together, taste and smell create what we experience as flavour.
Beyond taste and smell, two further senses shape our evaluation of food. Texture is detected by mechanoreceptors in the mouth — the crunch of a biscuit, the smoothness of a custard, the chewiness of a well-developed bread roll each come from different structural properties. Sound also plays a role: research shows that people perceive crisps as less fresh and stale when the sound of the crunch is dampened, even when the product has not changed. And appearance — colour, shape, portion size — sets expectations before any food reaches the mouth.
The five basic tastes are sweet, salty, sour, bitter and umami. Combined with aroma (olfactory system), texture (mechanoreceptors), appearance and sound, these create the complete sensory experience of eating. Flavour is mostly smell — which is why a blocked nose dramatically reduces perceived taste.
Sensory Testing: Setting Up a Tasting Panel
Sensory testing is used in food development to collect objective data about how a product looks, smells, tastes, feels and sounds. Simply asking friends “do you like this?” is not sensory evaluation — it is an informal opinion. A properly set-up tasting panel uses controlled conditions: a neutral-smelling room, consistent lighting, palate-cleansing water between samples, and coded samples (e.g. labelled 376, 842, 519 rather than A, B, C) to avoid expectation bias.
The two main types of sensory test students need to know are preference tests and profiling tests. In a preference test, panellists are asked to choose which sample they prefer, or to rank several samples from most to least preferred. These are useful when a manufacturer wants to know whether a new lower-fat version of a product is as acceptable as the original.
A sensory profile test (or star diagram) asks panellists to score multiple attributes — sweetness, saltiness, sourness, crunchiness, aftertaste, colour, aroma — on a numerical scale (typically 1–5 or 0–9). The scores are plotted on a star diagram, giving a visual ‘fingerprint’ of the product. If a revised recipe is too salty, the star diagram will show a spike on the “saltiness” axis that can guide the next iteration of the recipe.
A very common mark-scheme error is to describe sensory evaluation as “I asked some friends if they liked it.” This loses marks because it describes informal opinion, not a controlled test. The key differences are: (1) a tasting panel uses a defined method (preference, ranking or profiling); (2) samples are coded to prevent bias; (3) the environment is controlled (no competing aromas, consistent lighting, palate-cleansing water); (4) results are recorded on a standard proforma so data can be compared. Without these controls, individual preference and expectation bias distort the results. For the 3- or 4-mark questions that ask you to describe how to set up a sensory test, include all four of these control factors for full marks.
The Range of Factors That Influence Food Choice
What ends up on a plate is the result of dozens of overlapping influences. The spec groups these into personal, practical, social and value-based factors — and your exam questions often ask you to apply several at once to a named individual.
Enjoyment and personal preference are the most immediate drivers. A 15-year-old who has grown up eating spicy food may find bland school-canteen meals unsatisfying. Past experience shapes taste: repeated exposure to a food in a positive context (a family meal, a celebration) builds preference over time.
Cost and availability are major practical constraints. A single parent managing a tight weekly food budget may rely on cheaper carbohydrate staples (bread, rice, pasta) and fewer fresh vegetables or oily fish, even when they know the nutritional value of the latter. Availability — what is stocked in local shops, what is in season — limits choice regardless of preference.
Seasonality shapes both availability and cost: asparagus is far cheaper in May than in December; Scottish raspberries are at their most flavourful in July. Eating seasonally can reduce food miles and support local farmers, but limits variety for consumers who want the same foods year-round.
Time and lifestyle are increasingly powerful factors. A working parent arriving home at 7 pm after a school run may reach for a ready meal rather than a slow-cooked stew, even if the nutritional comparison favours the latter. Convenience-food manufacturers explicitly target time-poor consumers.
Religious dietary rules can shape every meal. Muslim consumers follow Halal guidelines: pork and its derivatives are forbidden, and other meat must be slaughtered according to Islamic law. Jewish dietary law (Kosher) prohibits pork and shellfish and requires meat and dairy to be kept strictly separate. Many Hindus are vegetarian or avoid beef because of the cow’s sacred status. These are non-negotiable constraints, not preferences — a food manufacturer making a product for a multi-faith school canteen must account for all three sets of rules simultaneously.
Ethical beliefs shape choice in a different way. A consumer concerned about animal welfare may choose free-range eggs even though they cost more. A consumer concerned about climate change may reduce red meat consumption in response to the environmental evidence linking livestock farming to greenhouse gas emissions. These choices are personal convictions rather than religious obligations, but they are increasingly influential as food labelling makes origin, welfare standards and carbon footprint more visible.
Medical reasons and personal choices also restrict what some people can safely eat. A person with coeliac disease must avoid gluten entirely; a person with a peanut allergy must check every label for traces. These are physiological necessities. Personal choices — veganism, a low-sugar diet, a preference for organic produce — are voluntary but may be just as strongly held.
Food Labelling, Marketing and Informed Choice
Food labelling is a key tool for informed choice. UK law (Food Information to Consumers regulations) requires pre-packaged food to show: the name of the food, a list of ingredients (in descending order by weight), allergens highlighted in bold, net quantity, a best before or use-by date, storage conditions, and the name and address of the manufacturer. Allergen labelling is legally mandatory: the 14 major allergens must be emphasised in the ingredients list (typically in bold).
Front-of-pack traffic light labelling uses colour coding (green / amber / red) to indicate whether each nutrient (fat, saturated fat, sugar, salt) is at a low, medium or high level per portion. Research shows that shoppers use traffic lights to make faster decisions, particularly for fat and sugar, compared with reference intake percentage labels alone. However, critics note that traffic lights can mislead when portion sizes are unrealistically small.
Marketing also shapes choice. Bright packaging, celebrity endorsement, product placement at eye level on supermarket shelves, and advertising targeted at children all influence purchasing behaviour. UK law restricts advertising of less healthy food and drink products on TV before 9 pm and paid-for advertising online at any time.
The full range of food-choice factors includes: enjoyment and preference; seasonality; cost and availability; time and lifestyle; celebration or occasion; culture and religion; ethical beliefs; and medical reasons (allergies, intolerances, health conditions). Exam questions often present a named individual (e.g. a Muslim teenager, a budget-conscious working parent) and ask you to apply at least three of these factors to their specific situation.