Taste Alteration
Supervised by DR. Lana Shabur Talabani Done by Sarab Naji Farah Ahmed Sharee Sabah Sandy QusayIntroduction
Taste is the ability to respond to dissolved molecules and ions. The sense of taste is also called Gustation. The substance which stimulate taste is called Tastants Tongue is the sense organ that detects taste and the sensory structure that detects taste stimuli are Taste Buds.Importance of taste
Appreciation of food and drink Selection of food Protection against toxins Important for the dentist Stimulates salivary secretion Governs use of oral hygiene aidsTongue Anatomy (Taste Related )
The tongue is covered with 4 types of projections called papillae Sharp or Filiform papillae : no taste buds Fungifiorm papillae : rounded with taste buds Circumvallate papillae : large papillae with taste buds Foliate papillaeVallate (Circumvallate) Papillae
About 12 very large circular Vallate papillae form an inverted V-shaped row at the back of the tongue. Each of these papillae contains approximately 100-300 taste buds.Vallate Papillae
Fungiform Papillae
The Fungiform (mushroom like) papillae are mushroom shaped elevations scattered over the entire surface of the tongue. They contain about 5 taste buds each.Filiform Papillae
Filiform papillae cover the entire surface of the tongue. They are pointed, threadlike structures that contain tactile receptors but no taste buds. They increase friction between the tongue and the food, making it easier for the tongue to move food into the oral cavity.Foliate Papillae
The foliate (leaflike) papillae are located in small trenches on the lateral margins of the tongue, but most of their taste buds degenerate in early childhood.Taste Buds
More than 10,000 or so taste buds are found on the tongue, also located on Soft palate, Cheeks, throat and lips! Taste buds are found in papillae of the tongue mucosa. A single taste bud contains 50-100 taste cells representing all 5 taste sensationsPrimary sensation of taste
For the practical analysis of taste these receptors have been grouped into five general categories called primary sensations of taste. They are Sour, Salty, Sweet, Bitter and UmamiCont… Sweet Sugars, saccharin, alcohol, and some amino acids are plentiful near the tip of the tongue. Salt Metal ions are abundant in the tip and upper portion of the tongue. Sour Hydrogen ions occur along the lateral edges of the tongue. Bitter Alkaloids such as quinine and nicotine are at the back of the tongue. Umami Elicited by the amino acid glutamate ( Protein )
Experiment
Objective To test the ability to identify familiar taste with eye closed Equipment Solution of 5% sucrose, 1% acetic acid, 5% NaCl and 0.5% quinine sulphat.
How to prepare the solutions
sweet solutionMix 2 teaspoons (~ 8 gr) of sugar in 1 glass (~250 ml) of water.Salt SolutionMix 3 teaspoons (~15 gr) of salt in 1 glass (~250 ml) of water.Sour SolutionIt usually takes 5-10 teaspoons of lemon juice per glass to get the solution to have the same “taste intensity” as your salt solutionBitter solutionMix 2 teaspoons (~114 mgr caffeine) of instant coffee in 1 glass (~250 ml) of waterProcedure
To test the sense of taste use strong solution of sugar (for sweet), common salt (for salt), weak solution of citric acid (for sour), and quinine (for bitter). Four vials of solutions are placed on the table with labels. Dry the tongue with paper towel and apply the different solutions with applicator stick/glass rod to the tip, sides and back of the tongue as followingWhy do the elders like to take in food with strong flavour?
It’s too salty! Do you know ?Because …. When you were a baby, you had taste buds, not only on your tongue, but on the sides and roof of your mouth. This means you were very sensitive to different foods. As you grew, the taste buds began to disappear from the sides and roof of your mouth, leaving taste buds mostly on your tongue. As you get older, your taste buds will become even less sensitive, so you will be more likely to eat foods that you thought were too strong as a child.
Remember
Spicy’ is not a taste. It is the sensation of pain in the tongue resulting fromthe destruction of taste buds by the‘hot’ food like chilly. It is spicy!Taste Disorders
Ageusia (complete loss of taste) Dysgeusia (persistent abnormal taste)What is impaired taste?
Impaired taste means that your sense of taste is not functioning properly. Impaired taste can refer to the absence of taste. It can also refer to an altered sense, such as a metallic taste in the mouth.Most people only experience impaired taste temporarily, and only lose part of their ability to taste. It’s very rare to lose your sense of taste completely.
What causes impaired taste?
Other causes of impaired taste include:smokinggum inflammation, such as gingivitis or periodontal diseasemedication, including lithium, thyroid medications, and cancer treatmentsSjogren’s syndrome, an autoimmune disease that causes dry mouth and dry eyes
5. head or ear injuries6. nutritional deficiencies, especially vitamin B-12 and zincPeople diagnosed with certain disorders, including multiple sclerosis and Bell’s palsy, may sometimes experience impaired taste.