DNA-Based Approaches for Traceability and Authentication of Olive Oil

Abstract

Abstract"uthentication and traceability of extra virgin olive oil is a challenging research task due to the complexity of fraudulent practices. Various chemical and biochemical techniques have been developed for determining the authenticity of olive oil and in recent years non-conventional methods based on DN" analysis have gained atention, due to high speciicity, sensitivity and reliability. DN" analyses have very high discriminating power because ultimately the unique identity of a variety or species is to a great extent genetically dependent. Polymorphisms are genetic variations which refer to the variation in populations or species. Molecular markers provide information on genetic variations and are valuable tools to determine olive oil authenticity. Recently several DN"-based methods have been developed to authenticate olive oil, since analysis of the residual oil DN" with the use of molecular markers can lead to the identiication of the variety or the plant species from which it was extracted. The aim of this chapter is to provide an overview of the current trends and critical issues on DN"-targeted approaches used for traceability and authenticity of olive oil. This is considered a rapidly expanding ield with signiicant challenges and prospects which shall be discussed thoroughly.

A Robust DNA Isolation Protocol from Filtered Commercial Olive Oil for PCR-Based Fingerprinting

“…However, they present some limits due to the difficulty in identifying the olive varieties used for oil production. Instead, DNA-based methods are more accurate and reliable than chemical methods; moreover, they are not influenced by environmental conditions [13]. Among the genetic markers used for cultivar identification and varietal traceability in processed foods, simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs) are the most suitable [14,15,16].…”

Authentication of olive oil based on DNA analysis

“…Therefore, by identifying the number of repeats found in the DNA isolated from a sample, a process performed by amplifying the target sequence by PCR amplification using specific primers, discrimination of the variety can be achieved. Usually, a combination of SSR markers is used to provide a more powerful discriminatory analysis (Bazakos et al, 2016). Some applications include expressed sequence tag SSR (EST-SSR), which derive from regions of the genome that are expressed (sequence coding for a specific protein) and therefore these regions have greater transferability among species and their variation can be associated with the phenotype (Duran et al, 2009).…”

“…RAPD, AFLP and ISSR have advantages when analyzing genetic relationships in olive trees mainly because the design of primers for the PCR do not require prior knowledge of the genome sequence. However, these markers have the drawback of low reproducibility in olive oil studies (reviewed by Pasqualone et al, 2016;Sebastiani and Busconi, 2017;Bazakos et al, 2016, Ben-Ayed et al, 2013. The genetic markers used by the most recent studies for olive oil authentication are simple sequence repeats (SSR) and single nucleotide polymorphisms (SNPs) (Pasqualone et al, 2016) and are located either in nuclear DNA or in the DNA found in organelles (chloroplast or mitochondrial DNA) (Pereira et al, 2018).…”