Determination of Lycopene Concentration in Fresh Tomatoes by Spectrophotometry: A Collaborative Study

Area of Science:

• Food Science
• Analytical Chemistry
• Nutritional Science

Background:

• Lycopene, a key phytonutrient in tomatoes, has garnered significant research interest due to its potential health benefits.
• Increasing consumer interest in Japan highlights the need for standardized methods to assess health-promoting food components.
• Accurate quantification of lycopene is crucial for research and quality control of tomato products.

Purpose of the Study:

• To develop and validate a method for determining lycopene content in tomatoes that conforms to the Japanese Agricultural Standard (JAS).
• To establish a reliable analytical procedure for lycopene quantification in fresh tomatoes.

Main Methods:

• A novel method utilizing a hexane-acetone mixture for lycopene extraction from fresh tomato samples.
• A collaborative study involving ten laboratories to assess the interlaboratory performance and reproducibility of the proposed method.
• Analysis of six test materials with varying lycopene concentrations (39–170 mg/kg) as blind duplicates.

Main Results:

• The method demonstrated high precision, with relative standard deviations for reproducibility (RSDR) ranging from 2.4% to 4.2%.
• Relative standard deviations for repeatability (RSDr) were between 1.2% and 3.0%, indicating consistent results within laboratories.
• HorRat values, a measure of method performance, fell within the acceptable range of 0.26–0.49.

Conclusions:

• The developed method for determining tomato lycopene content has been successfully validated through a collaborative study.
• The method exhibits acceptable precision and reproducibility, making it suitable for standardization in Japan.
• This standardized method will facilitate accurate lycopene content analysis in tomatoes for regulatory and research purposes.