Although bacterial contamination is traditionally identified by consumers as their primary food safety and quality concern, there is a wide variety of other potentially detrimental compounds and quality issues that must be supported by comprehensive analysis programs (Figure 1). Many of these, such as chemical residues, have been analyzed for decades. However, interest in others, such as genetically modified organisms (GMOs) and indirect additives from packaging, is relatively recent. Today, there are several key analytical trends that will have an integral effect on a food product's success and reputation in the marketplace. These include:
• Agricultural chemicals Biotechnology
• Carcinogens
• Direct food additives
• Packaging and indirect food additives
• Antibiotic and drug residues
• Allergens
• Traditional nutrients
• Phytochemicals and micronutrients
• Regulatory initiatives
The ability to respond to ever-evolving consumer attitudes, regulatory initiatives and scientific discoveries requires that the food manufacturing industry keeps its finger on the pulse of key safety concerns and the analytical methodologies required to monitor product safety, functionality and quality.
Accent on Agrochemicals
Although agricultural practices have drastically changed in recent decades, the threat of harmful pesticide residues in foods remains a major concern, especially given the advent of the global marketplace. Initiatives for worldwide harmonization of residue assays and tolerance levels have resulted in validated methods for many classes of compounds. Using a variety of chromatographic techniques, low-cost and high-throughput screens that can detect hundreds of pesticides for less than $1 per compound have been adopted. If a pesticide is detected, confirmatory analysis using additional chromatographic or mass spectrometry (MS) techniques are often done to provide more comprehensive data. A food matrix may contain hundreds of natural or man-made chemicals that can potentially interfere with the analytes of interest. As a result, the method used must take advantage of the analyte's physical and chemical properties to facilitate detection of the analyte from the matrix-derived interferences.
Most pesticide residue procedures involve separation using gas chromatography (GC), high-performance liquid chromatography (HPLC), or liquid chromatography (LC). Before separation, samples are subject to extraction and cleanup, which facilitates separation of the pesticide from the matrix and helps purify the extracts for quantification. After separation, residues are measured using a detection device, such as a mass spectrometer. The use of LC/MS techniques has grown significantly due to the increased availability of the instrumentation. This combination of separation and detection devices allows less stringent cleanup, minimizes the effects of interferences and, in some cases, allows the elimination of the confirmation step.