Evaluation of Tomato Juice Quality Using Surface Enhanced Raman Spectroscopy

Tomato (Lycopersicon esculentum L.) is a valuable fruit cultivated in the world as an important plant. There are a lot of industries engaged with the drying, processing, quality control and sorting of tomato. A rapid and reli-able measurement of qualitative factors of tomato and its products can be a serious necessity for the producers and industrialists. The objective of this research was to implement SERS as a modern technique to evaluate some qual-itative parameters of tomato juice. To prevent the effect of cartenoids and florescence background, the juices were centrifuged. Silver colloid was prepared according to Lee and Meisel method for SERS experiments. The results were compared with the spectra obtained from ordinary spontaneous Raman spectroscopy technique data. Three major bands assigned to carbohydrates in tomato were detected and analyzed. Moreover, a medium band related to proteins could be identified. Comparison of SERS spectra with the normal spontaneous Raman spectra proved that SERS has a privilege in the measurement of carbohydrates and proteins as an effective, rapid and precise technique. PACS numbers: 78.30.−j, 33.20.Fb 1