Carlton W Farley III has used Raman spectroscopy for detecting a variety of chemicals in the past few years, including explosives, rocket fuel propellants and EMA in food items. He completed his PhD in December 2015 at Alabama A&M University, where he began his research on “Improving EMA detection in extra virgin olive oil as well as honey, flour and baby formula”. He is currently a Research Associate at Alabama A&M University, where he trains graduate students as well as continues research on “Detection of EMA in food items”.
The adulteration of pure extra virgin olive oil (EVOO) with cheaper edible oils has been a major concern for consumers for some time. Thousands of truckloads of food products are brought into the US every day, making it impossible to police every truckload using current techniques. In order to police a higher number of oils and other foods imported into the US, we must have a much faster method for detection of EMA in food products. Raman spectroscopy offers such a solution. While the current methods of testing samples taken by the Center for Border Patrol (CBP) involves sending those samples to a lab, and waiting up to three weeks for results, we show a method where each border checkpoint could be equipped with a Raman spectrometer, and with little training, measurements can be made within 5 seconds so that Border Patrol agents can test several samples from each truckload entering the US. For this study, samples are kept inside clear glass containers, while a 785 nm Raman system is used to take measurements as the Raman probe is placed against the glass container. Several types of oils at various concentrations of adulteration are used. Ratios of peak intensities are used to analyze raw data, which allows for quick, easy and accurate analysis. While conventional Raman measurements of EVOO may take as long as 2 minutes, all measurements shown here are for integration times of just 5 s. It is found that adulteration of EVOO with cheaper oils is detectable at concentrations as low as 2.5% for all oils used in this study. This is more sensitive than standard techniques, but only requires a fraction of the time to test each sample.
Aura Daraba has her expertise in Food Safety and Food Quality, use of natural antimicrobials to control pathogens, use of non-thermal food processing technologies, and implementation of HACCP in Food Industry and in Food Service Units. She has worked extensively along with Dr. Aubrey Mendonca and Dr. Angela Shaw in the use of High Pressure Processing and use of Natural Antimicrobials to control pathogens in foods.
Statement of the Problem: In recent years several disease outbreaks were linked to unpasteurized juices contaminated with human enteric pathogens such as Salmonella enterica and Escherichia coli O157:H7 (CDC 2011; EFSA 2015). While heat pasteurization and canning can inactivate vegetative pathogens, such processes can destroy heat labile nutrients and negatively alter sensory characteristics of juices. Also growing consumer demands for foods which are nutritious, fresh-like, and devoid of synthetic preservatives, have forced juice manufacturers to explore non-thermal processes and natural antimicrobials for pathogen control in juices. The present study investigated the effect of low concentrations of cinnamaldehyde combined with high pressure processing (HPP) for killing S. enterica in carrot juice (CRJ) and a mixed berry juice (MBJ) at 4ºC. Methodology & Theoretical Orientation: CRJ (pH 6.25) and MBJ (pH 3.59) with added cinnamaldehyde (0.10, 0.15 and 0.25 μl/ml) were inoculated with S. enterica (5-strain; final concentration ~107 CFU/ml). Inoculated juices without added cinnamaldehyde served as control. Juices (4ºC) were packaged in polyester pouches and pressurized (400 or 300 MPa) for 60, 90 and 120 seconds. The time between inoculation and HPP was approximately 1.5 hours. Salmonella survived for 42 days or more in control CRJ following HPP (400 MPa) for 30, 60, or 120 s. Addition of cinnamaldehyde to juices increased the sensitivity of S. enterica to HPP. Cinnamaldehyde (0.25 μl/ml) combined with 400 MPa (60 s) inactivated S. enterica by more than 5.5-log in CRJ. In MBJ, cinnamaldehyde (0.15 μl/ml) with a lower pressure (300 MPa for 120 s) resulted in complete inactivation (negative enrichment) and greater than a 5-log10 CFU/ ml reduction of S. enterica. Conclusion & Significance: The use of CA in conjunction with HPP has good potential to serve as an alternative process for heat pasteurization of juices and meet the 5-log reduction performance standard as stipulated in the juice HACCP regulations.