Profiling of phenolic compounds from different apple varieties using comprehensive two-dimensional liquid...

Area of Science:

• Analytical Chemistry
• Food Science
• Chromatography

Background:

• Phenolic compounds in apples are crucial for health benefits and sensory properties.
• Accurate profiling of these complex compounds in food matrices remains challenging.
• Comprehensive two-dimensional liquid chromatography (LC×LC) offers enhanced separation capabilities.

Purpose of the Study:

• To apply LC×LC for detailed phenolic compound profiling in various apple varieties.
• To quantify total phenols and total procyanidins in different apple types.
• To demonstrate the efficacy of LC×LC for analyzing complex food samples.

Main Methods:

• Utilized hydrophilic interaction liquid chromatography (HILIC) in the first dimension and reversed-phase (RP) in the second dimension.
• Employed diode array detection (DAD) and mass spectrometry (MS) for compound identification.
• Performed in vitro assays to determine total phenol and procyanidin content.

Main Results:

• Achieved complete phenolic profiling of apples in under 50 minutes using LC×LC.
• Separated and tentatively identified diverse compounds including flavan-3-ols (procyanidin oligomers up to degree 8), dihydrochalcones, flavonols, and a phenolic acid.
• Reinette apples showed the highest total phenol content (6.46 mg GAE/g dry matter), while Granny Smith apples had the highest total procyanidins (0.73 mg epicatechin equiv./g dry matter).

Conclusions:

• LC×LC is a powerful and efficient technique for comprehensive phenolic compound profiling in complex food matrices like apples.
• Significant variations in phenolic compound profiles exist among different apple varieties.
• The developed LC×LC method provides valuable insights into apple composition and quality.