Rapid detection of walnut and pumpkin oil adulteration using Raman spectroscopy and partial least square methodology

  • Anca BECZE INCDO-INOE2000, Research Institute for Analytical Instrumentation, ICIA Cluj-Napoca Subsidiary, 400293 Cluj-Napoca
  • Dorina SIMEDRU INCDO-INOE2000, Research Institute for Analytical Instrumentation, ICIA Cluj-Napoca Subsidiary, 400293 Cluj-Napoca
Keywords: adulteration; partial least square methodology; Raman; pumpkin oil; walnut oils; spectroscopy; rapid detection


The purpose of this study is to develop a statistical method, based on Raman spectroscopy results, to quickly identify the adulteration of pumpkin and walnut oils. For this purpose, pure pumpkin and walnut oils from Cluj County, Romania were studied with Raman techniques. They were adulterated with sunflower oil at 14 levels of concentration, ranging from 2.5 to 50%. The areas under the significant peaks were quantified and compared. A statistical method using the partial least square methodology was developed and used as a prediction tool in order to establish the adulteration percentage for pumpkin and walnut oils. 4 components were used to model the equation, the peak areas from ~1264, ~1300, ~1441 and respectively ~1659 cm-1. The final model equations take into account only the peak areas that had a high impact on the prediction values, statistically proven using the p-value. The level of prediction obtained with the final model equation was ≥ 95%.


In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. The article is to be paginated when the complete issue will be ready for publishing (Volume 48, Issue 3, 2020). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue.


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How to Cite
BECZE, A., & SIMEDRU, D. (2020). Rapid detection of walnut and pumpkin oil adulteration using Raman spectroscopy and partial least square methodology. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 48(3). https://doi.org/10.15835/nbha48312024
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