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Citrus fruits freshness assessment using Raman spectroscopy
Fran Nekvapil1, Ioana Brezestean2, Daniel Barchewitz3
1Babeș-Bolyai University, Biomolecular Physics Department, Str. Kogălniceanu, Nr. 1, RO 400084 Cluj-Napoca, Romania; University of Dubrovnik, Department for Aquaculture, Ćira Carića 4, 20000 Dubrovnik, Croatia.
Food Chemistry
|October 18, 2017
Summary
Raman spectroscopy non-destructively assesses citrus fruit freshness by analyzing carotenoid signals in the peel. A novel Raman coefficient of freshness (CFresh) correlates with degradation over 20 days, enabling portable quality control.
Area of Science:
- Agricultural Science
- Analytical Chemistry
- Food Science
Background:
- Assessing citrus fruit freshness is crucial for consumer satisfaction and reducing food waste.
- Current methods for determining fruit freshness can be destructive or time-consuming.
- Non-destructive techniques are needed for efficient quality control in the food industry.
Purpose of the Study:
- To non-destructively evaluate the freshness of clementine, mandarin, and tangerine using Raman spectroscopy.
- To establish a correlation between carotenoid Raman signals and fruit degradation over time.
- To introduce a quantitative measure for fruit freshness.
Main Methods:
- Raman spectroscopy was used to analyze the carotenoid signaling in the peel of intact citrus fruits.
- Fruits were monitored over a 20-day period from harvest to physical degradation.
- A Raman coefficient of freshness (CFresh) was developed based on signal intensity changes.
Main Results:
- A strong correlation was observed between peel Raman signal intensity and citrus fruit freshness.
- The Raman coefficient of freshness (CFresh) showed a linearly decreasing trend over time.
- Different citrus varieties exhibited distinct slopes for their CFresh time course.
- Freshness assessment was successfully demonstrated using a portable Raman instrument.
Conclusions:
- Carotenoid Raman signal intensity is a reliable indicator of citrus fruit freshness.
- The developed Raman coefficient of freshness (CFresh) provides a quantitative measure for quality assessment.
- Portable Raman spectroscopy offers a viable non-destructive method for on-site fruit freshness evaluation, benefiting consumers and the food industry.
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