Sodium is an essential micronutrient and, via salt taste, appetitive. High consumption of sodium is, however, related to negative health effects such as hypertension, cardiovascular diseases and stroke. In industrialized countries, about 75% of sodium in the diet comes from manufactured foods and foods eaten away from home. Reducing sodium in processed foods will be, however, challenging due to sodium’s specific functionality in terms of flavor and associated palatability of foods (i.e., increase of saltiness, reduction of bitterness, enhancement of sweetness and other congruent flavors). The current review discusses the sensory role of sodium in food, determinants of salt taste perception and a variety of strategies, such as sodium replacers (i.e., potassium salts) and gradual reduction of sodium, to decrease sodium in processed foods while maintaining palatability.

The global high prevalence of hypertension and cardiovascular disease has raised concerns regarding the sodium content of the foods which we consume. Over 75% of sodium intake in industrialized diets is likely to come from processed and restaurant foods. Therefore international authorities, such as the World Health Organisation, are encouraging the food industry to reduce sodium levels in their products. Significant sodium reduction is not without complications as salt plays an important role in taste, and in some products is needed also for preservation and processing. The most promising sodium reduction strategy is to adapt the preference of consumers for saltiness by reducing sodium in products in small steps. However, this is a time-consuming approach that needs to be applied industry-wide in order to be effective. Therefore the food industry is also investigating solutions that will maintain the same perceived salt intensity at lower sodium levels. Each of these has specific advantages, disadvantages, and time lines for implementation. Currently applied approaches are resulting in sodium reduction between 20–30%. Further reduction will require new technologies. Research into the physiology of taste perception and salt receptors is an emerging area of science that is needed in order to achieve larger sodium reductions.

Repeated consumption of high-energy nutrient poor foods can lead to undesirable health outcomes such as obesity. Taste plays an important role in food choice, and a better understanding of the links between the taste of foods, individual taste preferences, food choices, and intakes will aid in our understanding of why some people might select and consume unhealthy foods. The present review focuses on three main questions: (1) do nutrient poor and nutrient rich foods significantly differ in taste profile? (2) are humans predisposed toward developing a liking or preference for certain taste profiles? (3) how are individual variations in liking of the basic taste qualities related to long term food intake and adverse health outcomes such as obesity? Results indicated that nutrient poor foods were likely to be sweet, salty and fatty mouthfeel, while the taste profiles of nutrient rich foods were diverse. Although humans are born with a universal liking for sweet and aversion for bitter taste, large individual differences exist in liking of all the basic taste qualities. These individual differences partly explain differences in short term intakes of foods varying in taste profiles. However they fail to sufficiently explain long term food choices and negative health outcomes such as obesity. Future studies should focus on how the full sensory profile of food which includes taste, smell and texture interacts with individual characteristics (e.g., taste or health motivations, taste preferences) to affect consumption of nutrient rich and nutrient poor foods.

Applied taste research is increasingly focusing on the relationship with diet and health, and understanding the role the sense of taste plays in encouraging or discouraging consumption. The concept of basic tastes dates as far back 3000 years, where perception dominated classification with sweet, sour, salty, and bitter consistently featuring on basic taste lists throughout history. Advances in molecular biology and the recent discovery of taste receptors and ligands has increased the basic taste list to include umami and fat taste. There is potential for a plethora of other new basic tastes pending the discovery of taste receptors and ligands. Due to the possibility for an ever-growing list of basic tastes it is pertinent to critically evaluate whether new tastes, including umami, are suitably positioned with the four classic basic tastes (sweet, sour, salty, and bitter). The review critically examines the evidence that umami, and by inference other new tastes, fulfils the criteria for a basic taste, and proposes a subclass named ‘alimentary’ for tastes not meeting basic criteria.

Objective: To investigate the effect of front-of-pack labels on taste perception and use of table salt for currently available and sodium-reduced soups.Design: Within-subject design.Setting: Sensory laboratory.Subjects: Participants (n 50, mean age 34·8 (sd 13·6) years) were randomly served nine soups (250 ml each) across 3 d. Servings differed in: (i) health label (i.e. no health label, reduced-salt label or Heart Foundation Tick); and (ii) sodium reduction (no reduction – benchmark, 15 % less sodium or 30 % less sodium). Before tasting, participants rated their expected salt intensity and liking. After tasting, participants rated their perceived salt intensity and liking, after which they could add salt to the soup to make it more palatable.Results: Reduced-salt labels generated a negative taste expectation and actual taste experience in terms of liking (P < 0·05) and perceived saltiness (P < 0·05). Perceived saltiness of sodium-reduced soups decreased more (P < 0·05), and consumers added more salt (P < 0·05), when soups carried the reduced-salt label. The tick logo and soups without health labels had no such influence on taste perception.Conclusions: Emphasizing salt reduction by means of a front-of-pack label can have a negative effect on taste perception and salt use, especially when consumers are able to taste differences between their regular soup and the sodium-reduced soup. Overall health logos which do not emphasize the reduction in salt are less likely to affect perceived salt intensity and therefore are viable solutions to indicate the healthiness of sodium-reduced products.