Possible Role of High-Molecular-Weight Salivary Proteins in Astringency Development
Elvira Manjón1, Ignacio García-Estévez1, María Teresa Escribano-Bailón1
1Department of Analytical Chemistry, Nutrition and Food Science, Universidad de Salamanca, E37007 Salamanca, Spain.
Foods (Basel, Switzerland)
|March 28, 2024
Summary
High-molecular-weight salivary proteins (HMWSPs) interact with dietary tannins, influencing astringency. Mucins significantly precipitate tannins, unlike albumin and alpha-amylase, highlighting their importance in taste perception.
Area of Science:
- Food science
- Biochemistry
- Sensory science
Background:
- Astringency is caused by food tannin and salivary protein interactions.
- Previous research focused on low-molecular-weight salivary proteins.
- The role of high-molecular-weight salivary proteins (HMWSPs) in astringency is understudied.
Purpose of the Study:
- To investigate molecular interactions between HMWSPs and dietary tannins.
- To characterize the binding mechanisms and precipitation effects.
Main Methods:
- Fluorescence quenching
- Isothermal Titration Calorimetry (ITC)
- High-Performance Liquid Chromatography-Mass Spectrometry with Diode Array Detection (HPLC-MS-DAD)
Main Results:
- All three tested HMWSPs (mucin, α-amylase, albumin) interact with flavan-3-ol tannin extracts.
- Mucin interaction leads to significant flavan-3-ol precipitation (approx. 90%).
- Albumin and α-amylase interactions result in lower flavan-3-ol precipitation (approx. 20%) via a 'sphere of action' mechanism.
Conclusions:
- HMWSPs, particularly mucins, play a crucial role in dietary tannin precipitation and astringency.
- Astringency analysis should incorporate HMWSPs for a comprehensive understanding.
- Understanding these interactions is key to controlling food sensory properties.
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