Infrared Radiation Assisted Digestion As A Greener Simple Method For Pork Meat Multielemental Analysis By MIP OES

CORA JOFRE, FLORENCIA; SAVIO, MARIANELA

Conferencia; 2nd European Sample Preparation e-Conference and 1st Green and Sustainable Analytical Chemistry e-conference; 2022

With a conception based on the lack of knowledge of the quality improvement of pork meat, product of the continuous genetic evolution and the animals nutritional management improvement in the stages of growth and fattening, some consumers criticize pork meat, for being an excessively fatty and nutritionally inadequate meat. This situation establishes the need to deepen the acquaintance about the nutritional value of pork meat obtained in the Argentinian production conditions, in order to promote consumption and tend to a better insertion into the national and international context, with traceability and quality certification.One of the main challenges in analytical chemistry has been to overcome the problems of bringing solid samples into solutions, which must be compatible with instrumental spectrochemical methods for the analysis of trace elements, such as microwave-induced plasma atomic spectrometry (MIP OES). Compared to the fast multi-element determination of MIP OES, the sample preparation time is a long process that consumes much of the analytical process. Sample preparation is a critical and essential step in the analytical procedure, especially for samples with complex matrices such as pork meat. Sample digestion methods using microwave radiation in closed systems are commonly used in the analysis of inorganic components; however, these methods are limited to small amounts of organic samples and the impossibility of digesting samples with different characteristics in the same cycle. Infrared (IR) radiation could be widely used based on its ability to promote rapid and efficient heating.In the present work, an IR-assisted digestion (IRAD) procedure using commercially available lamps was evaluated for pork meats. MIP OES was utilized for the determination of Ca, Cu, Co Fe, K, Mg, Mn, P, Na, Zn. The proposed procedure consisted of grinding and homogenizing the lyophilized meat samples, adding 1 mL of diluted nitric acid (7 mol L-1) to 0.15 g of the sample and exposing it to IR (this procedure was repeated again). Then, 1 mL of H2O2 (30%) was added and the samples were exposed to IR again (repeating the procedure twice). To validate the proposed IRAD methodology, Certified Reference Materials (CRM) were analyzed using the same treatment as the samples; analytical recoveries were between 80-120%, and precision (expressed in terms of relative standard deviation, RSD) was better than 10%.The use of IR was efficient for complex samples treatment, rich in organic compounds; the final digests were left without dissolved organic carbon content and with low residual acidity. Furthermore, the use of small volumes of dilute nitric acid makes it eco-friendly and with enhanced performance and productivity when it comes to quantifying the nutritional quality of pork meat. This was verified using the analytical eco-scale which is especially important in the new green methodologies search.