People were divided into three types based on their reaction to sour food

"Sour taste" is different for everyone. In addition, sour apple, lemon and, for example, sour dairy products can taste very differently.

Researchers from Penn State concluded that different organic acids give different "sourness" even at the same concentration, and the perception of sour includes not only the taste, but also the characteristic sensations in the mouth - "reduction" and "dryness". The results are published in the journal Food Quality and Preference.

The work continues the team's line of research on "extreme sour lovers": in a previous project, Penn State reported that about one in eight adults actually prefer very pronounced sourness.

In the new study, the researchers recruited 71 regular consumers (not professional tasters) who eat or drink sour foods at least once a month. Participants were given aqueous solutions with equal amounts (equimolar) of five food acids commonly used in the industry:

• lactic (sauerkraut, pickles, dairy products),

• malic acid (e.g., Granny Smith apples),

• fumaric (found in papaya, pears, plums, among others),

• tartaric (especially in grapes),

• citric acid (citrus fruits).
  Each acid was tested at four increasing concentrations. Participants rated acidity, puckering, drying, and overall like/dislike.

The outcome was not so obvious for the practice of "substitutes": equal amounts of different acids do not create equal acidity and equal "mofil". On average, citric acid produced the strongest acid sensation and "moufing", while lactic acid produced the weakest.

Based on the participants' reactions, the researchers identified three conditional segments:

1. those who sharply rejected the product as the acid intensified;

2. those whose dislike grew gradually;

3. and those who liked the experience better when it became more acidic. And the groups differed not only in their preferences, but also in how intensely they experienced sourness, "reduction" and "dryness," especially at high concentrations - and especially for acids other than citric acid.

Separately, the team tested a hypothesis that had previously worked for spicy and bitter: whether "sour lovers" were associated with certain personality traits. Here - no: they did not find a pronounced connection with personality traits. But preferences were better explained by food experience and habits (for example, more frequent consumption of citrus juices and tart fruits in those who like sourness).

The authors believe that the results may be useful for manufacturers: different acids give subtle differences in taste and sensation, which means that the formulation of "sour" products can be more accurately adjusted to different consumer segments.