Assessment of Lipid Peroxidation Products in Adult Formulas: GC-MS Determination of Carbonyl and Volatile Compounds Under Different Storage Conditions  
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1 Department of Technique and Food Development, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences (WULS-SCGW), 0-276 Warszawa, Poland; [EMAIL_ADDRESS]  
[PERSON]  
2 Laboratorio Assocado para a Quimica Verde (REQUMITE/LAQV)-Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, 4169-007 Porto, Portugal; [EMAIL_ADDRESS] (A.R.S. ); [EMAIL_ADDRESS] (P.J.A. ); [EMAIL_ADDRESS] (I.R.S. ); [EMAIL_ADDRESS] (J.A.R.) [PERSON]  
1 Department of Technique and Food Development, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences (WULS-SCGW), 0-276 Warszawa, Poland; [EMAIL_ADDRESS]  
[PERSON]  
2 Laboratorio Assocado para a Quimica Verde (REQUMITE/LAQV)-Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, 4169-007 Porto, Portugal; [EMAIL_ADDRESS] (A.R.S. ); [EMAIL_ADDRESS] (P.J.A. ); [EMAIL_ADDRESS] (I.R.S. ); [EMAIL_ADDRESS] (J.A.R.) [PERSON]  
2 Laboratorio Assocado para a Quimica Verde (REQUMITE/LAQV)-Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, 4169-007 Porto, Portugal; [EMAIL_ADDRESS] (A.R.S. ); [EMAIL_ADDRESS] (P.J.A. ); [EMAIL_ADDRESS] (I.R.S. ); [EMAIL_ADDRESS] (J.A.R.) [PERSON]  
2 Laboratorio Assocado para a Quimica Verde (REQUMITE/LAQV)-Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, 4169-007 Porto, Portugal; [EMAIL_ADDRESS] (A.R.S. ); [EMAIL_ADDRESS] (P.J.A. ); [EMAIL_ADDRESS] (I.R.S. ); [EMAIL_ADDRESS] (J.A.R.) [PERSON]  
3 Department of Analytical Chemistry, Nutrition and Food Science, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain 344  
tailored for specific health conditions [3; 4]. Ultra-high temperature treatment, commonly used in adult formula processing, rapidly heats products to 135-150 \({}^{\circ}\)C for a few seconds to destroy harmful microorganisms and extend shelf life without refrigeration [5]. However, this process can also lead to the formation of heat-induced contaminants, such as lipid peroxidation products and advanced glycation end-products (AGEs), which may pose health risks to consumers [6]. Among the most concerning contaminants are malondialdehydedehyde (MDA), formaldehyde (FCHO), acetaldehyde (ACE), acrolein (ACRL), methylglyoxal (MGO), diacetyl (DA) (the structural formula is provided in the Supplementary Materials, Figure S1), and other various volatile organic compounds (VOCs) [7]. These compounds are formed during lipid peroxidation as polyunsaturated fatty acids interact with reactive oxygen species [6; 7]. This process follows a radical-driven pathway, forming lipid hydroperoxides as primary oxidation products [7]. These hydroperoxides decompose into more stable secondary products, including carbonyl compounds such as malondialdehydedehyde, formaldehyde, acetaldehyde, acrolein, methylglyoxal, and diacetyl [7]. These compounds indicate oxidative degradation in lipid-containing foods like adult formula [6; 7]. Lipid peroxidation can continue when the formulas are stored along with other degradation processes, potentially affecting their nutritional quality and safety [6; 7]. Monitoring the presence and concentrations of these contaminants is crucial due to their toxicological profiles and classifications by health authorities, including the International Agency for Research on Cancer (IARC), which identifies several of these compounds as potential carcinogens [7]. For instance, FCHO is classified as a carcinogen with sufficient evidence of its carcinogenicity to humans (Group 1) with a tolerable daily intake (TDI) set at 150 \(\upmu\)g/kg body weight (bw)/day. ACRL is classified as probably carcinogenic to humans (Group 2A), with a lower TDI of 7.5 \(\upmu\)g/kg bw/day.