To distinguish the density of a particular suspension (mixtures of water and non-fat substances, such as proteins) or emulsion (mixtures containing lipids), it is suggested to introduce a teaspoon in a glass and observe its rate of fall against the edge: [15]

• Liquid: teaspoon falls immediately;
• Semi-liquid: teaspoon falls more slowly;
• Semi-solid: teaspoon falls very slowly or not at all.

Patients who have recently undergone implant procedures are advised to use broth (a typical liquid emulsion) to dilute solid food that cannot be easily emulsified (e.g. spreadable cheese, homogenized food, eggs). Broth can be used as a diluent in small or large quantities depending on the time that has elapsed since surgery. Another liquid that can be used as diluent is milk. In cases where patients have lactose intolerance, soy milk may be used instead of cow's milk [16]. Typical semi-solid emulsions are sauces. Mayonnaise allows the food preparer to make semi-solid emulsions more viscous. Béchamel sauce (white sauce) is as versatile as mayonnaise but contains fewer calories. Typically, the more viscous the food, the easier it is to swallow and the less oral preparation it requires. Butter, margarine, and olive oil can also be used as lubricants to reduce friction during swallowing and therefore avoid chewing. However, overconsumption of products that contain large amounts of fat is not suited to a balanced diet.