Study on lycopene and antioxidant contents variations in tomatoes under air-drying process

Area of Science:

• Food Science
• Agricultural Science
• Nutritional Science

Background:

• Lycopene and major antioxidant contents (MACs) are crucial for tomato's nutritional value.
• Air-drying is a common method for tomato processing, but it can affect antioxidant stability.
• Understanding the impact of processing factors on these compounds is vital for preserving tomato quality.

Purpose of the Study:

• To investigate the effects of tomato cultivars, drying temperatures, and drying time on lycopene and MACs during air-drying.
• To identify optimal conditions and tomato types for maximizing antioxidant retention.
• To propose a threshold for MACs related to lycopene stability during drying.

Main Methods:

• Investigated lycopene and MACs (total phenolics + total flavonoids) in different tomato cultivars.
• Applied air-drying at temperatures of 40, 80, and 120°C for durations up to 240 minutes.
• Analyzed the relationship between drying parameters, tomato cultivar, and antioxidant content.

Main Results:

• Lycopene content increased initially (first 60 min) across all temperatures.
• Red cultivars (HR, SN, TTL) showed significant lycopene decrease at 120°C after 75 min.
• A proposed MAC threshold of 500 mg/100 g dry matter was identified, below which lycopene drops rapidly.

Conclusions:

• Drying temperature and time significantly impact lycopene and MACs in tomatoes.
• Yellow tomato cultivars, with higher initial MACs and better retention at 40-80°C, are suitable for thermal processing.
• Maintaining MACs above a critical threshold is essential for preserving lycopene during air-drying.