Determination of advanced glycation endproducts in cooked meat products

AGEs in cooked meat: Production, detection, and mechanisms of its inhibition by plant extracts

With the growing demand for food safety and nutrition, the challenge of ensuring the quality of cooked meat products while reducing the accumulation of AGEs during processing needs urgent attention. In this study, the patterns of AGEs production, detection methods, quality contribution, and molecular mechanisms of its inhibition by natural plant-based extracts (NPBE) in cooked meat products were comprehensively reviewed. NPBE can effectively reduce the accumulation of AGEs in meat by binding to AGEs precursors and reducing glycosylation sites. It has also been shown to significantly remove off-flavour, and inhibit protein carbonylation. The potential for synergistic inhibition of AGE formation using NPBE and exogenous physical field treatments such as pulsed electric fields, microwave irradiation, thermal cycling of air, and ultrasound was emphasized, as well as the urgent need for the development of portable AGE detectors integrated with artificial intelligence and big data analytical models. This study indicates the future research direction for inhibiting the generation of AGEs in cooked meat products, which can promote and guide the practical application of NPBE in cooked meat products.

Excessive oil absorption and maillard reaction products in fried muscle foods: Formation mechanisms, potential health risks and mitigation strategies

Fried muscle foods are popular among consumers for their golden color, fried flavor, and crispy exterior paired with a tender interior. However, physicochemical reactions occurring during frying lead to the formation of harmful components. This review focuses on the formation mechanisms of excessive oil and Maillard reaction products (advanced glycation end products, and heterocyclic amines) in fried muscle foods including protein oxidation, starch gelatinization, and generation of carbonyls and free radicals. The gastrointestinal digestion, absorption, and potential health risks of these components are discussed. It also summarizes the measures to inhibit oil absorption in four ways, including reducing initial moisture content, controlling moisture migration, reducing frying oil usage, and reducing interfacial tension between oil and food. Finally, it reviews mitigation strategies of Maillard reaction products from two aspects: reducing precursors, and trapping intermediates. This review may help produce healthier fried muscle foods.

Accumulation of Nε-carboxymethyllysine and Nε-carboxyethyllysine in precooked pork during cold storage and subsequent reheating

This research aimed to investigate the levels of Nε-carboxymethyllysine (CML) and Nε-carboxyethyllysine (CEL) in precooked pork (100 °C, 10 min) as affected by storage (0 °C, 0-11 d) and subsequent reheating (100 °C, 5 min). A longer storage duration led to more CML (average increased: 69-128 %) and CEL (average increased: 11-44 %) in precooked pork, while the reheating resulted in average increases of 86 % CML and 32 % CEL compared to their initial levels in precooked pork. However, the storage duration did not significantly (p > 0.05) affect CML/CEL formation in precooked pork during the subsequent reheating. The levels of CML/CEL and glyoxal/methylglyoxal had no obvious relationship, but CML formation was linked to lipid oxidation in precooked or reheated pork. The accumulation of CML and CEL in precooked meat produced during the initial precooking, storage, and reheating implies the necessity to control their generation in these products.

Mechanism studies of gliadin-glucose glycation reaction and products formation by heat treatment with different conduction modes

Heat treatments induce protein-reducing sugar glycation reactions easily, leading to protein structural transformations and advanced glycation end products generation. In this study, effects of four heat conduction modes (air, contact, vapour and liquid-conduction) on the spatial conformation and glycation products of gliadin-glucose system were evaluated. The results showed that gliadin tertiary structure expanded and exposed more hydrophobic sites in vapour-conduction, resulting in more glycation sites. Conversely, air-conduction promoted the protein folded, causing a lighter glycation degree and lower glyoxal, methylglyoxal, acrylamide, 5-hydroxymethylfurfural and carboxymethyl lysine contents (following vapour-conduction > contact-conduction > liquid-conduction > air-conduction). The above phenomena were attributed to the different water content in the different conduction modes. Furthermore, the glycation sites identified in vapour-conduction and contact-conduction were approximately two-fold of that in air-conduction. Conclusively, gliadin-glucose systems subjected to air-conduction showed less glycated intensity and hazardous products.

Assessing metal-induced glycation in French fries

Non-enzymatic glycation is the chemical reaction between the amine group of an amino acid and the carbonyl group of a reducing sugar. The final products of this reaction, advanced glycation end-products (AGEs), are known to play a key role in aging and many chronic diseases. The kinetics of the AGE formation reaction depends on several factors, including pH, temperature, and the presence of prooxidant metals, such as iron and copper. In this study, the effect of iron and copper on the rate and outcome of non-enzymatic glycation was examined in the test tube and a food model, using chromatography and spectrometry methods. Binding efficiencies of several chelating agents to selected metals were also assessed. Phytic acid was the most efficient of the tested chelating agents. The effect of phytic acid on AGE formation in French fries was evaluated. While phytic acid treatment increased the amounts of UV-absorbing compounds in fries, a food ingredient rich in phytic acid showed the opposite effect. This study suggests that prooxidant metals can affect the rate, outcome, and yield of the non-enzymatic glycation reaction and that they do so differently when free or chelated. Moreover, despite being an excellent iron chelator, phytic acid can promote AGE formation in fried food potentially via mechanisms other than metal-induced glycation.

Formation and kinetic analysis of AGEs in Pacific white shrimp during frying

Advanced glycation end products (AGEs) are complex and heterogeneous compounds closely associated with various chronic diseases. The changes in Nε-carboxymethyllysine (CML), Nε-carboxyethyllysine (CEL), Nε-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1), and fluorescent AGEs (F-AGEs) in fried shrimp during frying (170 °C, 0-210 s) were described by kinetic models. Besides,the correlations between AGEs contents and physicochemical indicators were analyzed to reveal their intrinsic relationship. Results showed that the changes of four AGEs contents followed the zero-order kinetic, and their rate constants were ranked as kCML < kCEL ≈ kMG-H1 < kF-AGEs. Oil content and lipid oxidation were critical factors that affected the AGEs levels of the surface layer. Protein content and Maillard reaction were major factors in enhancing the CML and CEL levels of the interior layer. Furthermore, the impact of temperature on the generation of CML and CEL was greater than that of MG-H1 and F-AGEs.

Advanced Glycation End Products and Health: A Systematic Review

Advanced glycation end products (AGEs) have garnered significant attention due to their association with chronic diseases and the aging process. The prevalence of geriatric diseases among young individuals has witnessed a notable surge in recent years, potentially attributed to the accelerated pace of modern life. The accumulation of AGEs is primarily attributed to their inherent difficulty in metabolism, which makes them promising biomarkers for chronic disease detection. This review aims to provide a comprehensive overview of the recent advancements and findings in AGE research. The discussion is divided into two main sections: endogenous AGEs (formed within the body) and exogenous AGEs (derived from external sources). Various aspects of AGEs are subsequently summarized, including their production pathways, pathogenic mechanisms, and detection methods. Moreover, this review delves into the future research prospects concerning AGEs. Overall, this comprehensive review underscores the importance of AGEs in the detection of chronic diseases and provides a thorough understanding of their significance. It emphasizes the necessity for further research endeavors to deepen our comprehension of AGEs and their implications for human health.

The contribution of dietary advanced glycation end-products and genetic risk in the development of inflammatory bowel disease: a prospective cohort study

BACKGROUND

Dietary advanced glycation end products (AGEs) may promote oxidative stress and inflammation in the gastrointestinal tract.

AIMS

The aim of this study is to investigate the association between dietary AGE intake and the risk of inflammatory bowel disease (IBD).

METHODS

We included 121,978 participants without IBD at baseline from the UK Biobank. We estimated consumption of three common AGEs (Nε-(carboxymethyl)-lysine (CML), Nε-(1-carboxyethyl)-lysine (CEL), and Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1)) by matching 24-h dietary questionnaires to a validated dietary AGE database. We used Cox proportional hazards regression models to calculate the hazard ratio (HR) and 95% CI of the association between dietary AGEs and IBD risk.

RESULTS

During a median follow-up of 13.72 years, 671 participants developed IBD (192 with Crohn's disease (CD) and 478 with ulcerative colitis (UC)). Among the assessed dietary AGEs, only CEL was associated with an increased risk of IBD (HR = 1.09, 95% CI: 1.01-1.18, p = 0.020) and CD (HR = 1.18, 95% CI: 1.03-1.36, p = 0.014), particularly for participants who were overweight, physically inactive, and non-smokers. Among participants at a high genetic risk of CD, HRs (95% CI) of CD were 1.26 (1.00-1.57) for CML, 1.41 (1.12-1.77) for CEL, and 1.28 (1.01-1.62) for MG-H1 (p < 0.05 for each). However, none of the dietary AGEs was significantly associated with UC risk, irrespective of genetic predisposition.

CONCLUSIONS

Dietary CEL was associated with an increased risk of IBD and CD, but not UC. Further interventional studies are required to support the potential benefit of AGE restriction, especially for individuals at a high genetic risk of CD.

Inhibition of Nε-(carboxyethyl)lysine and Nε-(carboxymethyl)lysine formation in beef, chicken, and fish meat: A comparative study of oven frying and air frying with a marinade-containing Micromeria fruticosa

The objective of this study was to assess the impact of marinating beef, chicken, and fish with Micromeria fruticosa (M. fruticosa) on the inhibition of Nε-(carboxyethyl)lysine (CEL) and Nε-(carboxymethyl)lysine (CML). Furthermore, our objective was to examine how different cooking techniques, temperatures, and durations affect the creation of CEL and CML in these meat products. The study began with the characterization of M. fruticosa. Subsequently, meat samples were marinated using an M. fruticosa-containing marinade and stored at 4 ± 1°C for 24 h. Following storage, the meats underwent cooking in an oven at 200°C for 12 min and in an air fryer at 250°C for 8 min. Subsequently, pH, color, thiobarbituric acid reactive substances (TBARS), as well as CEL and CML analyses were conducted. M. fruticosa had high levels of biological activity and bioactive content. Moreover, increasing the M. fruticosa ratio in the marinade demonstrated a reduction in TBARS, CML, and CEL formation. This study concludes that M. fruticosa can be effectively used as a marinade component for meat, inhibiting the formation of CEL and CML. In conclusion, this research underscores the significant potential of M. fruticosa in reducing the synthesis of advanced glycation end products (AGEs) during meat processing. These results not only enhance our comprehension of the complex relationship between plant extracts and meat quality but also present encouraging prospects for fostering healthier and safer cooking methods.

Dietary glycation compounds - implications for human health

The term "glycation compounds" comprises a wide range of structurally diverse compounds that are formed endogenously and in food via the Maillard reaction, a chemical reaction between reducing sugars and amino acids. Glycation compounds produced endogenously are considered to contribute to a range of diseases. This has led to the hypothesis that glycation compounds present in food may also cause adverse effects and thus pose a nutritional risk to human health. In this work, the Senate Commission on Food Safety (SKLM) of the German Research Foundation (DFG) summarized data on formation, occurrence, exposure and toxicity of glycation compounds (Part A) and systematically assessed potential associations between dietary intake of defined glycation compounds and disease, including allergy, diabetes, cardiovascular and renal disease, gut/gastrotoxicity, brain/cognitive impairment and cancer (Part B). A systematic search in Pubmed (Medline), Scopus and Web of Science using a combination of keywords defining individual glycation compounds and relevant disease patterns linked to the subject area of food, nutrition and diet retrieved 253 original publications relevant to the research question. Of these, only 192 were found to comply with previously defined quality criteria and were thus considered suitable to assess potential health risks of dietary glycation compounds. For each adverse health effect considered in this assessment, however, only limited numbers of human, animal and in vitro studies were identified. While studies in humans were often limited due to small cohort size, short study duration, and confounders, experimental studies in animals that allow for controlled exposure to individual glycation compounds provided some evidence for impaired glucose tolerance, insulin resistance, cardiovascular effects and renal injury in response to oral exposure to dicarbonyl compounds, albeit at dose levels by far exceeding estimated human exposures. The overall database was generally inconsistent or inconclusive. Based on this systematic review, the SKLM concludes that there is at present no convincing evidence for a causal association between dietary intake of glycation compounds and adverse health effects.

Formation and Reduction of Toxic Compounds Derived from the Maillard Reaction During the Thermal Processing of Different Food Matrices

Advanced glycation end products (AGEs), heterocyclic aromatic amines (HAAs), acrylamide (AA), 5-hydroxymethylfurfural (5-HMF), and polycyclic aromatic hydrocarbons (PAHs) are toxic substances that are produced in certain foods during thermal processing by using common high-temperature unit operations such as frying, baking, roasting, grill cooking, extrusion, among others. Understanding the formation pathways of these potential risk factors, which can cause cancer or contribute to the development of many chronic diseases in humans, is crucial for reducing their occurrence in thermally processed foods. During thermal processing, food rich in carbohydrates, proteins, and lipids undergoes a crucial Maillard reaction, leading to the production of highly active carbonyl compounds. These compounds then react with other substances to form harmful substances, which ultimately affect negatively the health of the human body. Although these toxic compounds differ in various forms of formation, they all partake in the common Maillard pathway. This review primarily summarizes the occurrence, formation pathways, and reduction measures of common toxic compounds during the thermal processing of food, based on independent studies for each specific contaminant in its corresponding food matrix. Finally, it provides several approaches for the simultaneous reduction of multiple toxic compounds.

Inhibitory effect of homemade hawthorn vinegar-based marinade on Nε-(carboxymethyl)lysine and Nε-(carboxyethyl)lysine formation in beef tenderloins

In this study, the inhibitory effects of homemade hawthorn vinegar-based marinade on the formation of Nε-(carboxymethyl) lysine (CML) and Nε-(carboxyethyl) lysine (CEL) during the cooking of beef tenderloins investigated. Additionally, the goal was to determine the bioactive compounds present in hawthorn vinegar that could contribute to these effects, both quantitatively and qualitatively. For this purpose, hawthorn vinegar was first produced from hawthorn fruit and characterized. Then, beef tenderloins were marinated at two different concentrations (25% and 50%) and three different marination times (2, 6 and 24 h) and cooked in a airfryer at 200 °C for 12 min. After the cooking process, analyses were conducted for CML, CEL, thiobarbituric acid reactive substances (TBARS), sensory and color. Hawthorn vinegar was found to have high phytochemical and bioactivity properties. It was found that hawthorn vinegar significantly altered the color properties (L*, a*, and b*) of raw beef tenderloin samples (P < 0.05). The marinating process did not adversely affect the sensory properties of the beef tenderloin, other than odour, and even improved its texture and appearance. Increasing the marination concentration and time significantly inhibited CML and CEL formation (P < 0.05), marinating the meat for 24 h reduced CML formation from 13.75 μg/g to 2.5 μg/g, while CEL formation decreased from 17.58 μg/g to 16.63 μg/g. Although CEL was inhibited at low levels during marination, it remained stable. In conclusion, this study showed that hawthorn vinegar contains bioactive compounds that significantly inhibit the formation of CML and stabilize the formation of CEL.

Simultaneous determination of advanced glycation end products and heterocyclic amines in roast/grilled meat by UPLC-MS/MS

Advanced glycation end products (AGEs) and heterocyclic amines (HAs) are main harmful Maillard reaction products of meat products. Simultaneous quantification of both with high sensitivity, selectivity and accuracy remains a major challenge due to inconsistencies in their pre-treatment and instrumental methods and the different polarity of AGEs and HAs. We developed a method for the simultaneous determination of AGEs and HAs in roast/grilled meat by ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) using dynamic multiple reaction monitoring (D-MRM). The instrument parameters and pre-treatment method were optimized to achieve reasonably good separation and high response for the 11 target analytes within 8 min. From 10 to 200 ng/mL, the limits of detection (LODs) and limits of quantitation (LOQs) ranged from 0.3 to 5.5 μg/L and 0.9 to 6.3 μg/L, respectively, and the correlation coefficient (R2) was >0.99. It was acceptable to recoveries, standard deviations (RSDs), and matrix effects. Six types of roast/grilled meat samples were then tested using the developed method.

The effects of using sheep tail fat and cooking time on carboxymethyl-lysine formation and some quality characteristics of heat-treated sucuk

The study's aim was to determine the effect of using sheep tail fat (STF) on carboxymethyl-lysine (CML) content and other properties of heat-treated sucuk (HTS), a type of semi-dry fermented sausage. Three mixtures were prepared: 100% beef fat (BF), 50% BF + 50% STF, and 100% STF. After production (fermentation, heat treatment, and drying), the samples were cooked at 180°C for 0, 1, 3, and 5 min to determine the effect of cooking time on CML, thiobarbituric acid reactive substance (TBARS), total sulfhydryl, and carbonyl contents. The lowest pH value (5.50) was observed in the presence of STF. The most oleic acid (46.02%) was observed in the 100% STF group. The score of taste and general acceptability decreased with increasing STF. Using STF had no significant effect on TBARS, total sulfhydryl, carbonyl, or CML content. These parameters were affected by cooking time. The mean CML content increased from 55.77 to 72.90 μg/g after 5 min of cooking. CML correlated more strongly with TBARS than sulfhydryl or carbonyl.

Estimation of Advanced Glycation End Products in Selected Foods and Beverages by Spectrofluorimetry and ELISA

Advanced glycation end products (AGEs) are formed within the body as a part of normal metabolism and are also the by-products of cooking food. The elevated levels of AGEs in the body are considered pathogenic. The modern diets contain high levels of AGEs which are getting incorporated into the body AGEs pool and contribute to post-diabetic and age-related complications. The objective of the present study is to estimate the cross-linked AGEs (AGE-fluorescence) and the more stable carboxymethyl-lysine (CML) by spectrofluorimetry and ELISA in 58 kinds of foods in India. It was evident from the results that the foods cooked at higher temperatures showed high levels of AGEs. Among the studied foods, the highest fluorescence was observed in Biscuits 2 (362 AU), and the highest level of carboxymethyl lysine (CML) was found in Soya milk (659.3 ng/g). However, there was less correlation between the AGE-fluorescence and the CML content of the food samples. Processed food such as tomato sauce, chilli sauce, and cheese, along with western foods like chicken nuggets, pizza, and biscuits like Biscuits 2, are known to contain high levels of AGEs. In the present study a preliminary database of AGE-fluorescence and CML content of 58 foods was developed, which is the first attempt among Indian foods. Furthermore, elaborated database can be developed including maximum consumed foods in India which will help in suggesting a better diet for the diabetic population.

Qualitative and quantitative assessment of key aroma compounds, advanced glycation end products and heterocyclic amines in different varieties of commercially roasted meat products

Studies on the interactions and links between aroma and hazardous compounds were inadequately investigated. A complete analysis was conducted on the key aroma compounds, typical hazardous compounds and their precursors in 25 samples of roasted meats. Forty-nine aroma compounds were identified as essential odorants with odor-activity values exceeds 1. Nε-carboxymethyl lysine (CML, 11.78-49.32 μg/g) and Nε-carboxyethyl lysine (CEL, 8.48-171.00 μg/g) were identified as representative advanced glycation end products (AGEs) of meats with high concentrations. Harman and Norharman were typical heterocyclic aromatic amines. Meanwhile, correlation analysis indicated that aldehyde and alcohols showed a negative correlation with AGEs (p < 0.01), while pyrazines might affect the formation of Harman and Norharman. The furaldehyde, 1-hexanol, 2, 4-Decadienal, AGEs, and creatine were regarded as potential biomarkers that distinguished different roasted meat products. Therefore, the study could provide new insights for synergistic regulation of aroma and hazardous compounds in roasted meat products.

Evaluation of the effects of dietary advanced glycation end products on inflammation

Advanced glycation end products (AGEs) are a large number of heterogeneous compounds formed by the glycation of proteins, fats or nucleic acids. Endogenous AGEs have been associated with various health problems such as obesity, type 2 diabetes mellitus and cardiovascular disease. Inflammation is thought to be one of the main mechanisms in the development of these disorders. Although AGEs are produced endogenously in the body, exogenous sources such as smoking and diet also contribute to the body pool. Therefore, when the AGE pool in the body rises above physiological levels, different pathological conditions may occur through various mechanisms, especially inflammation. While the effects of endogenous AGEs on the development of inflammation have been studied relatively extensively, and current evidence indicates that dietary AGEs (dAGEs) contribute to the body's AGE pool, it is not yet known whether dAGEs have the same effect on the development of inflammation as endogenous AGEs. Therefore, this review aimed to evaluate the results of cross-sectional and intervention studies to understand whether dAGEs are associated with inflammation and, if there is an effect on inflammation, through which mechanisms this effect might occur.

Association of total and different food-derived advanced glycation end-products with risks of all-cause and cause-specific mortality

Background: advanced glycation end-products (AGEs), formed through a series of non-enzymatic reactions, can promote inflammation and oxidative stress. Their accumulation in the body has been linked to cardiovascular disease (CVD) and cancer. However, the association of total AGEs and AGEs from different food sources with risks of all-cause, CVD, and cancer mortality is still unknown. Methods: we conducted a prospective cohort study of a nationally representative sample of 22 124 participants from the National Health and Nutrition Examination Survey (NHANES) III (1988-1994) and NHANES 2003-2006. A food frequency questionnaire (FFQ) was utilized to calculate total and different food-derived AGE intake. Associations between various dietary AGE scores and the risk of all-cause, CVD, and cancer mortality were assessed by weighted Cox proportional hazard regression models. Results: over a median follow-up period of 27.1 years, we found that in the general population, AGE scores of both baked foods and meat were risk factors for all-cause, CVD, and cancer mortality. Specially, higher AGE scores in total and those derived from 10 of the 13 food groups were statistically associated with an increased risk of CVD mortality. Egg-, fruit-, and vegetable-derived AGE scores were positively correlated with the risk of cancer mortality. Additionally, there were positive multiplicative and additive interactions between smoking and meat-derived AGE scores on all-cause mortality. Conclusions: high amounts of AGE consumption is associated with an increased risk of CVD mortality, and meat and baked food-derived AGEs were positively linked to all-cause, CVD, and cancer mortalities. Adherence to unhealthy lifestyles, such as smoking, may increase mortality from leading causes in individuals with AGE-enriched diet habits.

Exploring the role of Maillard reaction and lipid oxidation in the advanced glycation end products of batter-coated meat products during frying

The Maillard reaction occurs during the frying of batter-coated meat products, resulting in the production of advanced glycosylation products that are harmful to human health. This study investigated the effects of frying temperature (140, 150, 160, 170 and 180 ℃) and time (80, 100, 120, 140 and 160 s) on the quality, advanced glycation end product (AGE) level and the relationship between these parameters in batter-coated meat products were investigated. The results showed that with an increase in frying temperature and time, the moisture content of the batter-coated meat products gradually decreased, the thiobarbituric Acid Reactive Substance (TBARS) values and oil content increased to 0.37 and 21.7 %, respectively, and then decreased, and CML and CEL content increased to 7.30 and 4.86 mg/g, respectively. Correlation analysis showed that the moisture content and absorbance at 420 nm, as well as TBARS values, were highly correlated with the oil content in batter-coated meat products. Additionally, the absorbance at 420 nm and TBARS levels were significantly correlated with AGE levels. Moreover, the AGE content in batter-coated meat products was less variable at lower frying temperatures or shorter frying times, and the influence of temperature on AGE formation was greater than that of time. Overall, these findings may help to better control the cooking conditions of batter-coated meat products based on AGE profiles.

Simultaneous analysis of advanced glycation end products using dansyl derivatization

Herein, new pre-column derivatization based on dansylation is present to resolve analytical difficulties, such as chromatographic separation difficulty, in identifying and quantifying advanced glycation end products (AGEs) owing to their high hydrophilicity, wide variety, and structural similarity. The proposed analytical method facilitated the separation of 14 AGEs, including structural isomers. Limits of detection of 1.0-43.3 ng/mL and linear ranges of the double- or triple-digit were achieved. Intra- and inter-day precisions of 1.1-3.0% and 1.3-3.1%, respectively, were achieved for standard solutions, while those for food specimens were 1.4-11.2% and 1.7-15.7%, respectively. The matrix effect was insignificant with regard to the percent recoveries and differences between slopes for both the standard solutions and food specimens. Furthermore, the quantitation results of AGEs in foods (coffee, beer, and sausage) and glycated proteins revealed the potential applicability of the developed method in various fields of food chemistry and biochemistry.

Inhibitory effect of Paliurus spina-christi Mill., Celtis tournefortii L. and Nigella sativa L. on Nε-(Carboxymethyl) lysine in meatballs

This study was conducted to examine the effect of cooking at different temperatures on the formation of Nε-(carboxymethyl) lysine (CML) after adding Paliurus spina-christi Mill. (PSC), Celtis tournefortii L. (CT) fruits, and Nigella Sativa L. (NS) seeds to the meatballs. Phytochemical and bioactivity properties were determined before adding PSC, CT fruits, and NS seeds to the meatballs. Then, PSC, CT fruits, and NS seeds were added to the meatballs at a rate of 2% and stored at 4 ± 1 °C for 16 days. CML, TBARS, pH, and aw analyses were performed on the meatballs. The highest phytochemical and bioactivity levels were detected in PSC fruit. The aw values detected in the meatball groups were found to be between 0.931 and 0.951 on the 0th day and between 0.963 and 0.985 on the 16th day, and the pH values ranged from 5.66 to 6.06 on the 0th day and from 6.10 to 6.74 on the 16th day. TBARS values of the meatballs were found to be between 1.17 and 1.98 on day 0 and 1.70-3.34 mg MDA/kg on day 16. CML levels in the meatballs were determined to be between 11.15 and 13.45 on day 0 and between 13.43 and 18.17 μg/g on day 16. The highest a* value was found in the meatballs with added CT fruit. It was determined that NS seeds had a negative effect on the a* value of the meatballs. In conclusion, adding PSC, CT fruits, and NS seeds can imbue meatballs with functional properties, thereby creating a more health-beneficial product for humans.

Effect of Pretreatment Methods on the Formation of Advanced Glycation End Products in Fried Shrimp

Fried shrimp are popular for their attractive organoleptic and nutritional qualities. However, consumers are more concerned about the safety of fried foods. To investigate the formation of advanced glycation end products (AGEs) in fried shrimp and provide pretreatment guidance for producing low-AGEs fried pacific white shrimp were treated with seven pretreatment methods before frying. The AGEs contents, physicochemical indicators, and their correlations in the fried shrimps' interior, surface, and batter layer were analyzed. Results indicated that pretreatment methods influenced both Maillard and oxidation reactions by altering the basic compositions, which controlled the formation of AGEs. The highest and lowest AGEs contents were obtained in shelled shrimp with exscinded back and whole shrimp, respectively. The batter-coated treatment reduced the AGEs contents in samples but increased the oil content. Correlation analysis showed that lipid oxidation was the decisive chemical reaction to the formation of AGEs by promoting the generation of dicarbonyl compounds and their combination with free amino acids. Conclusively, the whole shrimp was suitable for producing fried shrimp with low AGEs, oil content, and desirable color.

Effect of edible oil type on the formation of protein-bound Nε-(carboxymethyl)lysine in roasted pork patties

Protein-bound Nε-(carboxymethyl)lysine (CML), an advanced glycation end product within meat products, poses a potential health risk to humans. The objective of this study was to explore the impact of various edible oils on the formation of protein-bound CML in roasted pork patties. Eleven commercially edible oils including lard oil, corn oil, palm oil, olive oil, flaxseed oil, blended oil, camellia oil, walnut oil, soybean oil, peanut oil, and colza oil were added to pork tenderloin mince, respectively, at a proportion of 4 % to prepare raw pork patties. The protein-bound CML contents in the pork patties were determined by HPLC-MS/MS before and after roasting at 200 °C for 20 min. The results indicated that walnut oil, flaxseed oil, colza oil, olive oil, lard oil, corn oil, blended oil, and palm oil significantly reduced the accumulation of protein-bound CML in pork patties, of which the inhibition rate was in the 24.43 %-37.96 % range. Moreover, the addition of edible oil contributed to a marginal reduction in the loss of lysine. Meanwhile, glyoxal contents in pork patties were reduced by 16.72 %-43.21 % after roasting. Other than blend oil, all the other edible oils restrained protein oxidation in pork patties to varying degrees (between 20.16 % and 61.26 %). In addition, camellia oil, walnut oil, and flaxseed oil increased TBARS values of pork patties by 2.2-8.6 times when compared to the CON group. After analyzing the fatty acid compositions of eleven edible oils, five main fatty acids (palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid) were selected to establish Myofibrillar protein-Glucose-fatty acids systems to simulate the roasting process. The results showed that palmitic acid, oleic acid, linoleic acid, and linolenic acid obviously mitigated the formation of myofibrillar protein-bound CML, exhibiting suppression rates ranging from 10.38 % to 40.32 %. In conclusion, the addition of specific edible oil may curb protein-bound CML production in roasted pork patty by restraining protein or lipid oxidation, reducing lysine loss, and suppressing glyoxal production, which may be attributed to the fatty acid compositions of edible oils. This finding provides valuable guidance for the selection of healthy roasting oils in the thermal processing of meat products.

Investigation of Advanced Glycation End-Products, α-Dicarbonyl Compounds, and Their Correlations with Chemical Composition and Salt Levels in Commercial Fish Products

The contents of free and protein-bound advanced glycation end-products (AGEs) including Nε-carboxymethyllysine (CML) and Nε-carboxyethyllysine (CEL), along with glyoxal (GO), methylglyoxal (MGO), chemical components, and salt in commercially prepared and prefabricated fish products were analyzed. Snack food classified as commercially prepared products exhibited higher levels of GO (25.00 ± 3.34-137.12 ± 25.87 mg/kg of dry matter) and MGO (11.47 ± 1.39-43.23 ± 7.91 mg/kg of dry matter). Variations in the contents of free CML and CEL increased 29.9- and 73.0-fold, respectively. Protein-bound CML and CEL in commercially prepared samples were higher than those in raw prefabricated ones due to the impact of heat treatment. Levels of GO and MGO demonstrated negative correlations with fat (R = -0.720 and -0.751, p < 0.05) in commercially prepared samples, whereas positive correlations were observed (R = 0.526 and 0.521, p < 0.05) in raw prefabricated ones. The heat-induced formation of protein-bound CML and CEL showed a negative correlation with the variations of GO and MGO but was positively related to protein levels in prefabricated products, suggesting that GO and MGO may interact with proteins to generate AGEs during heating. The influence of NaCl on the formation of GO and MGO exhibited variations across different fish products, necessitating further investigation.

Higher dietary advanced glycation products intake is associated with increased risk of dementia, independent from genetic predisposition

BACKGROUND

Dietary advanced glycation end products (AGEs) might exert adverse effects on cognition. The associations between dietary AGEs and long-term risk of dementia are yet to be assessed in large population studies. We aimed to explore whether elevated dietary AGEs intake is associated with increased risk of dementia, and whether this association might be affected by genetic risk.

METHODS

A prospective cohort study, which included a total of 93,830 participants (aged≥ 50 years) free from dementia at baseline of the UK Biobank study (2006-2010) and had at least two 24-h dietary assessments and were followed up until 2021. Dietary AGEs, including Nε-(1-Carboxyethyl)-l-lysine (CEL), Nε-(carboxymethyl) lysine (CML), and Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1) were estimated via averaged data from the multiple 24-h food assessments according to the ultra-performance LC-tandem MS based dAGEs database. Incidence of all-cause dementia was ascertained through hospital inpatient and mortality records. Multivariable Cox regression models were utilized to estimate hazards ratios (HRs) and 95% confidence interval (CI) of dementia risk associated with dietary AGEs.

RESULTS

During a median follow-up of 11.9 years, 728 participants developed dementia. In multivariable adjusted model, when comparing the highest with the lowest tertile of intake level, HRs (95% CI) of dementia were 1.43 (1.16, 1.76) for total AGEs Z score, 1.53 (1.25, 1.89) for CEL, 1.27 (1.03, 1.56) for CML and 1.24 (1.02, 1.52) for MG-H1 (all P trend<0.01). There was no significant interaction between dietary AGEs intake, genetic risk and APOE ε4 carrier status for dementia.

CONCLUSIONS

Higher intakes of dietary AGEs including CEL, CML and MG-H1 were associated with a higher risk of dementia, independent from genetic risk, highlighting the significance of dietary AGEs restriction for dementia prevention.

The role of diet in multiple sclerosis onset and course: results from a nationwide retrospective birth-year cohort

OBJECTIVE

To examine (1) the association between childhood diet and developing MS, age of onset and onset type and (2) the association between diet at age 50 and disability and MRI volumes in people with MS (PwMS).

METHODS

The study enrolled 361 PwMS born in 1966 and 125 age- and sex-matched healthy controls (HCs). Information on individual dietary components (fruit, vegetables, red meat, oily fish, whole-grain bread and candy, snacks and fast food) and MS risk factors at the age of 10 and 50 years were collected using questionnaires. Overall diet quality score was calculated for each participant. Multivariable regression analyses were used to evaluate the association between diet at childhood and developing MS, age of onset and onset type and to evaluate diet at age 50, disability and MRI outcomes.

RESULTS

Poorer overall diet quality and individual dietary components during childhood (less whole-grain bread, more candy, snacks and fast food and oily fish) were associated with developing MS and onset type (all p < 0.05), but not with the age of onset. Fruit consumption at age 50 was associated with lower disability (Q3 vs. Q1: -0.51; 95% CI: -0.89 to -0.13). Furthermore, several individual dietary components at age 50 were associated with MRI volumetric measures. Higher-diet quality at age 50 was only associated with lower lesion volumes in PwMS (Q2 vs. Q1: -0.3 mL; 95% CI: -0.5 to -0.02).

INTERPRETATION

We demonstrate significant associations between dietary factors in childhood and developing MS, age of onset and onset type and between dietary factors at age 50 and disability and MRI-derived volumes.

The Effects of Sheep Tail Fat, Fat Level, and Cooking Time on the Formation of Nε-(carboxymethyl)lysine and Volatile Compounds in Beef Meatballs

This study aimed to determine the effects of fat type (sheep tail fat (STF) and beef fat (BF)), fat levels (10, 20, or 30%), and cooking time (0, 2, 4, and 6 min, dry heat cooking at 180 °C) on the carboxymethyl lysine (CML) content in meatballs. pH, thiobarbituric acid reactive substance (TBARS), and volatile compound analyses were also performed on the samples. The use of STF and the fat level had no significant effect on the pH value. The highest TBARS value was observed with the combination of a 30% fat level and STF. CML was not affected by the fat level. The highest CML content was determined in meatballs with STF at a cooking time of 6 min. In the samples cooked for 2 min, no significant difference was observed between STF and BF in terms of the CML content. STF generally increased the abundance of aldehydes. Aldehydes were also affected by the fat level and cooking time. A PCA provided a good distinction between groups containing STF and BF regardless of the fat level or cooking time. Pentanal, octanal, 2,4-decadienal, hexanal, and heptanal were positively correlated with CML.

Advanced glycation end product signaling and metabolic complications: Dietary approach

Advanced glycation end products (AGEs) are a heterogeneous collection of compounds formed during industrial processing and home cooking through a sequence of nonenzymatic glycation reactions. The modern western diet is full of heat-treated foods that contribute to AGE intake. Foods high in AGEs in the contemporary diet include processed cereal products. Due to industrialization and marketing strategies, restaurant meals are modified rather than being traditionally or conventionally cooked. Fried, grilled, baked, and boiled foods have the greatest AGE levels. Higher AGE-content foods include dry nuts, roasted walnuts, sunflower seeds, fried chicken, bacon, and beef. Animal proteins and processed plant foods contain furosine, acrylamide, heterocyclic amines, and 5-hydroxymethylfurfural. Furosine (2-furoil-methyl-lysine) is an amino acid found in cooked meat products and other processed foods. High concentrations of carboxymethyl-lysine, carboxyethyl-lysine, and methylglyoxal-O are found in heat-treated nonvegetarian foods, peanut butter, and cereal items. Increased plasma levels of AGEs, which are harmful chemicals that lead to age-related diseases and physiological aging, diabetes, and autoimmune/inflammatory rheumatic diseases such as systemic lupus erythematosus and rheumatoid arthritis. AGEs in the pathophysiology of metabolic diseases have been linked to individuals with diabetes mellitus who have peripheral nerves with high amounts of AGEs and diabetes has been linked to increased myelin glycation. Insulin resistance and hyperglycemia can impact numerous human tissues and organs, leading to long-term difficulties in a number of systems and organs, including the cardiovascular system. Plasma AGE levels are linked to all-cause mortality in individuals with diabetes who have fatal or nonfatal coronary artery disease, such as ventricular dysfunction. High levels of tissue AGEs are independently associated with cardiac systolic dysfunction in diabetic patients with heart failure compared with diabetic patients without heart failure. It is widely recognized that AGEs and oxidative stress play a key role in the cardiovascular complications of diabetes because they both influence and are impacted by oxidative stress. All chronic illnesses involve protein, lipid, or nucleic acid modifications including crosslinked and nondegradable aggregates known as AGEs. Endogenous AGE formation or dietary AGE uptake can result in additional protein modifications and stimulation of several inflammatory signaling pathways. Many of these systems, however, require additional explanation because they are not entirely obvious. This review summarizes the current evidence regarding dietary sources of AGEs and metabolism-related complications associated with AGEs.

Quantitative microbiological risk assessment of nontyphoidal Salmonella in ground pork in households in Chengdu, China

Foodborne disease caused by nontyphoidal Salmonella (NTS) is one of the most important food safety issues worldwide. The objectives of this study were to carry out microbial monitoring on the prevalence of NTS in commercial ground pork, investigate consumption patterns, and conduct a quantitative microbiological risk assessment (QMRA) that considers cross-contamination to determine the risk caused by consuming ground pork and ready-to-eat food contaminated during food handling in the kitchen in Chengdu, China. The food pathway of ground pork was simplified and assumed to be several units according to the actual situation and our survey data, which were collected from our research or references and substituted into the QMRA model for simulation. The results showed that the prevalence of NTS in ground pork purchased in Chengdu was 69.64% (95% confidence interval [CI], 60.2-78.0), with a mean contamination level of -0.164 log CFU/g. After general cooking, NTS in ground pork could be eliminated (contamination level of zero). The estimated probability of causing salmonellosis per day was 9.43E-06 (95% CI: 8.82E-06-1.00E-05), while the estimated salmonellosis cases per million people per year were 3442 (95% CI: 3218-3666). According to the sensitivity analysis, the occurrence of cross-contamination was the most important factor affecting the probability of salmonellosis. To reduce the risk of salmonellosis caused by NTS through ground pork consumption, reasonable hygiene prevention and control measures should be adopted during food preparation to reduce cross-contamination. This study provides valuable information for household cooking and food safety management in China.

Advanced Glycation End Products: A Comprehensive Review of Their Detection and Occurrence in Food

The Maillard reaction (MR) is a complicated chemical process that has been extensively studied. Harmful chemicals known as advanced glycation end products (AGEs), with complex structures and stable chemical characteristics, are created during the final stage of the MR. AGEs can be formed both during the thermal processing of food and in the human body. The number of AGEs formed in food is much higher compared to endogenous AGEs. A direct connection exists between human health and the build-up of AGEs in the body, which can result in diseases. Therefore, it is essential to understand the content of AGEs in the food we consume. The detection methods of AGEs in food are expounded upon in this review, and the advantages, disadvantages, and application fields of these detection methods are discussed in depth. Additionally, the production of AGEs in food, their content in typical foods, and the mechanisms influencing their formation are summarized. Since AGEs are closely related to the food industry and human health, it is hoped that this review will further the detection of AGEs in food so that their content can be evaluated more conveniently and accurately.

Contents and Correlations of Nε-(carboxymethyl)lysine, Nε-(carboxyethyl)lysine, Acrylamide and Nutrients in Plant-Based Meat Analogs

High temperatures applied in the production of plant-based meat analogs (PBMA) lead to the occurrence of Maillard reactions, in which harmful compounds Nε-(carboxymethyl)lysine (CML), Nε-(carboxyethyl)lysine (CEL) and acrylamide are formed. However, little research has focused on these compounds in PBMA. In this study, the contents of CML, CEL and acrylamide in 15 commercial-sold PBMA were determined by an ultra-high performance liquid chromatograph coupled with a triple quadrupole tandem mass spectrometer (UHPLC-QqQ-MS/MS). Nutrients (protein, amino acids, fatty acids and sugars) which are related to the formation of these compounds were also studied. The results showed that CML, CEL and acrylamide contents were in the range of 16.46-47.61 mg/kg, 25.21-86.23 mg/kg and 31.81-186.70 μg/kg, respectively. Proteins account for 24.03-53.18% of PBMA. Except for Met + Cys, which is the limiting amino acid of most PBMA, all other indispensable amino acids met the requirements for adults. Besides, PBMA had more n-6 fatty acids than n-3 fatty acids. A correlation analysis showed that proteins and the profiles of amino acid and fatty acid had little influence on CML but significant influence on CEL and acrylamide. The results of the present study can be used as a reference to produce PBMA with higher amounts of nutrients and lower amounts of CML, CEL and acrylamide.

Quantitation of α-Dicarbonyls, Lysine- and Arginine-Derived Advanced Glycation End Products, in Commercial Canned Meat and Seafood Products

Commercial sterilization is a thermal processing method commonly used in low-acid canned food products. Meanwhile, heat treatment can significantly promote advanced glycation end product (AGE) formation in foodstuffs. In this research, the validated analytical methods have been developed to quantitate both lysine- and arginine-derived AGEs and their precursors, α-dicarbonyls, in various types of commercial canned meat and seafood products. Methylglyoxal-hydroimidazolone 1 was the most abundant AGEs found in the canned food products, followed by Nε-(carboxyethyl)lysine, Nε-(carboxymethyl)lysine, and glyoxal-hydroimidazolone 1. Correlation analysis revealed that methylglyoxal and glyoxal were only positively associated with the corresponding arginine-derived AGEs, while their correlations with the corresponding lysine-derived AGEs were not significant. Importantly, we demonstrated for the first time that total sugar and carbohydrate contents might serve as the potential markers for the prediction of total AGEs in canned meats and seafoods. Altogether, this study provided a more complete view of AGEs' occurrence in commercial canned food products.

Insight into the effect of traditional frying techniques on glycosylated hazardous products, quality attributes and flavor characteristics of grass carp fillets

This study aimed to evaluate the evolution of quality attributes, oxidation index, glycosylated hazardous products, aroma characteristics of grass carp fillets and their relationship under air-frying, roast-frying and pan-frying. With frying progressed, the level of carbonyl protein and lipid oxidation products increased significantly (following air-frying > pan-frying > roast-frying), and the latter decreased subsequently after 6 min. Fillets possessed by frying increased significantly N^ε-carboxymethyl-lysines (CML) and 5-hydroxymethylfurfural (5-HMF) levels, whose increment was pan-frying > air-frying > roast-frying. Compared to raw, eighty-seven volatiles were identified and the total concentrations of those increased gradually in air-frying, but then decreased up to 6 min in roast-frying and pan-frying. Furthermore, significant correlations between CML, TBARS and 5-HMF, quality attributes, oxidation index; volatiles (VIP and/or OAV > 1) and lipid oxidation index were obtained. Conclusively, fillets possessed by air-/roast-frying showed more lipid oxidation and alcohols/aldehydes, while pan-fried enriched CML and pyrazines.

Research advances of advanced glycation end products in milk and dairy products: Formation, determination, control strategy and immunometabolism via gut microbiota

Advanced glycosylation end products (AGEs) are a series of complex compounds which generate in the advanced phase of Maillard reaction, which can pose a non-negligible risk to human health. This article systematically encompasses AGEs in milk and dairy products under different processing conditions, influencing factors, inhibition mechanism and levels among the different categories of dairy products. In particular, it describes the effects of various sterilization techniques on the Maillard reaction. Different processing techniques have a significant effect on AGEs content. In addition, it clearly articulates the determination methods of AGEs and even discusses its immunometabolism via gut microbiota. It is observed that the metabolism of AGEs can affect the composition of the gut microbiota, which further has an impact on intestinal function and the gut-brain axis. This research also provides a suggestion for AGEs mitigation strategies, which are beneficial to optimize the dairy production, especially innovative processing technology application.

Advanced Glycation End Products and Nitrosamines in Sausages Influenced by Processing Parameters, Food Additives and Fat during Thermal Processing

Advanced glycation end products (AGEs) and nitrosamines (NAs) in sausage are associated with pathogenic and carcinogenic risks. However, the multiple reaction parameters affecting the production of AGEs and NAs during sausage processing remain unclear. This experiment evaluated the effects of processing parameters, food additives and fat ratios on the formation of AGEs and NAs in sausages. The results showed a 2-3-fold increase in N^ε-(carboxymethyl)lysine (CML) and N^ε-(carboxyethyl)lysine (CEL) when the sausage processing temperature was increased from 90 °C to 130 °C, and N-nitrosodimethylamine (NDEA) increased from 3.68 ng/g to 6.41 ng/g. The addition of salt inhibited the formation of AGEs and NAs, and the inhibitory ability of 2 g/100 g of salt was 63.6% for CML and 36.5% for N-nitrosodimethylamine (NDMA). The addition of 10 mg/kg nitrite to sausages reduced CML formation by 43.9%, however, nitrite had a significant contribution to the formation of NAs. The addition of fat only slightly contributed to the production of CML. In addition, the relationship between α-dicarbonyl compounds and the formation of AGEs was investigated by measuring the changes in α-dicarbonyl compounds in sausages. The results showed two trends of AGEs and α-dicarbonyl compounds: AGEs increased with the increase in α-dicarbonyl compounds and AGE level increased but α-dicarbonyl compound level decreased.

Inhibitory effect of LSOPC on AGEs formation and sensory quality in cookies

At the conclusion of the Maillard reaction (MR), free amino groups of proteins, amino acids, or lipids with the carboxyl groups of reducing sugars to form stable molecules known as advanced glycation end products (AGEs), which hasten aging and may potentially be the root cause of a number of chronic degenerative diseases. According to researches, lotus seedpod oligomeric procyanidins (LSOPC), a premium natural antioxidant produced from lotus waste, can be included in cookies to improve flavor and lower the risk of illnesses linked to AGEs. In this work, we used cookies without LSOPC as a control to examine the effects of adding various concentrations of LSOPC (0, 0.05, 0.1, 0.2, and 0.4%) on the AGEs formation and the sensory quality in cookies. The amounts of AGEs and N-ε-carboxymethyl lysine (CML) decreased with the increase of LSOPC concentration, indicating that the concentration of LSOPC was positively correlated with the ability to inhibit AGEs formation. It was also demonstrated that the amount of antioxidant capacity of the cookies increased significantly with the increase of LSOPC concentration. On the other hand, the chromaticity, texture, electronic nose, and other aspects of the cookies' sensory attributes were also evaluated. The color of the cookies deepened and the flavor varied as LSOPC added content increased. The sensory quality of the cookies was examined, and the findings indicated that LSOPC would somewhat improve that quality. These findings implied that AGEs formation could be decreased in cookies while also enhancing their sensory quality by adding LSOPC.

Effect of Baking Temperature and Time on Advanced Glycation End Products and Polycyclic Aromatic Hydrocarbons in Beef

ABSTRACT

Beef is an important red meat that contains essential nutrients for human growth and development. Baking is a popular beef cooking method. Temperature and time play key roles in the final quality of beef. How temperature and time affect the changes of nutrients and the formation of harmful products in beef is not clear. The purpose of this study was to measure the content of water, fat, protein, ash, nitrite, total volatile base nitrogen, advanced glycation end products (AGEs) and their precursors, and polycyclic aromatic hydrocarbons (PAHs) at different temperatures (150, 190, 230, 270, and 310°C) for 20 min and at 190°C for different times (10, 20, and 30 min), so as to discuss the effect of different temperatures and times on beef nutrients and harmful products. The results showed that the moisture content of beef decreased with increased baking temperature and time, resulting in the increase of the relative content of fat, protein, and ash. The content of total volatile base nitrogen increased continuously. Compared with the control group, the content of glyoxal in beef decreased, whereas the content of methylglyoxal, pentosidine, and fluorescent AGEs increased, indicating the continuous accumulation of AGEs in beef. A total of 13 PAHs were identified by gas chromatography-mass spectrometry. The concentrations of 13 PAHs in beef increased with increases in baking temperature and time. The concentrations of BkP and BaP, which are the most carcinogenic to humans, were 0.36 and 0.35 μg/kg in raw meat, respectively; these were increased by high temperature and long baking times. After beef was baked at 270 and 310°C for 20 min, the concentration of BkP increased to 9.49 and 5.66 μg/kg, respectively, and the concentration of BaP increased to 5.45 and 4.42 μg/kg, respectively. After baking at 190°C for 30 and 40 min, the concentration of BkP increased to 4.81 and 24.20 μg/kg, respectively, and the concentration of BaP increased to 3.85 and 17.79 μg/kg, respectively.

HIGHLIGHTS

Cross-linking reactions in food proteins and proteomic approaches for their detection

Various protein cross-linking reactions leading to molecular polymerization and covalent aggregates have been described in processed foods. They are an undesired side effect of processes designed to reduce bacterial load, extend shelf life, and modify technological properties, as well as being an expected result of treatments designed to modify raw material texture and function. Although the formation of these products is known to affect the sensory and technological properties of foods, the corresponding cross-linking reactions and resulting protein polymers have not yet undergone detailed molecular characterization. This is essential for describing how their generation can be related to food processing conditions and quality parameters. Due to the complex structure of cross-linked species, bottom-up proteomic procedures developed to characterize various amino acid modifications associated with food processing conditions currently offer a limited molecular description of bridged peptide structures. Recent progress in cross-linking mass spectrometry for the topological characterization of protein complexes has facilitated the development of various proteomic methods and bioinformatic tools for unveiling bridged species, which can now also be used for the detailed molecular characterization of polymeric cross-linked products in processed foods. We here examine their benefits and limitations in terms of evaluating cross-linked food proteins and propose future scenarios for application in foodomics. They offer potential for understanding the protein cross-linking formation mechanisms in processed foods, and how the inherent beneficial properties of treated foodstuffs can be preserved or enhanced.

Modulation of 1,2-Dicarbonyl Compounds in Postprandial Responses Mediated by Food Bioactive Components and Mediterranean Diet

Glycoxidative stress with the consequent generation of advanced glycation end products has been implied in the etiology of numerous non-communicable chronic diseases. During the postprandial state, the levels of 1,2-dicarbonyl compounds can increase, depending on numerous factors, including characteristics of the subjects mainly related to glucose metabolism disorders and nutritional status, as well as properties related to the chemical composition of meals, including macronutrient composition and the presence of dietary bioactive molecules and macromolecules. In this review, we examine the chemical, biochemical, and physiological pathways that contribute to postprandial generation of 1,2-dicarbonyl compounds. The modulation of postprandial 1,2-dicarbonyl compounds is discussed in terms of biochemical pathways regulating the levels of these compounds, as well as the effect of phenolic compounds, dietary fiber, and dietary patterns, such as Mediterranean and Western diets.

Effect of Traditional Stir-Frying on the Characteristics and Quality of Mutton Sao Zi

The effects of stir-frying stage and time on the formation of Maillard reaction products (MRP) and potentially hazardous substances with time in stir-fried mutton sao zi were investigated. Furosine, fluorescence intensity, Nε-(1-carboxymethyl)-L-lysine (CML), Nε-(1-carboxyethyl)-L-lysine (CEL), polyaromatic hydrocarbons PAHs), heterocyclic aromatic amines (HAAs), and acrylamides (AA) mainly presented were of stir-fried mutton sao zi. The furosine decreased after mixed stir-frying (MSF) 160 s due to its degradation as the Maillard reaction (MR) progressed. The fluorescent compound gradually increased with time during the stir-frying process. The CML and CEL peaked in MSF at 200 s. AA reached its maximum at MSF 120 s and then decreased. All the 5 HAAs were detected after MSF 200 s, suggesting that stir-frying mutton sao zi was at its best before MSF for 200 s. When stir-frying exceeded the optimal processing time of (MSF 160 s) 200 s, the benzo[a]pyrene peaked at 0.82 μg/kg, far lower than the maximum permissible value specified by the Commission of the European Communities. Extended stir-frying promoted MRP and some hazardous substances, but the content of potentially hazardous substances was still within the safety range for food.