Effects of different cooking methods on methylglyoxal scavenging potential of meat under simulated gastrointestinal conditions

Investigation of formation of AGEs precursors, hydroxymethylfurfural and malondialdehyde in oleogel added cakes using an in vitro simulated gastrointestinal digestive system

The baking process has the potential to generate health-risk compounds, including products from lipid oxidation and Maillard reaction. Pre- and post-digestion levels of hydroxymethylfurfural (HMF), malondialdehyde (MDA), glyoxal (GO), and methylglyoxal (MGO) were studied in cakes formulated with hazelnut and sunflower oil, along with their oleogels as margarine substitutes. The concentration of HMF in oil and oleogel-formulated cakes increased after digestion compared to cakes formulated with margarine. The MDA values were between 82 and 120 μg/100 g in oil and oleogel formulated cakes before digestion and a decrease was observed after digestion. The substitution of margarine with oil and oleogels resulted in the production of high amounts of GO and MGO in cakes. However, the highest bioaccessibility as 318.2% was found in cakes formulated by margarine for GO. Oleogels may not pose a potential health benefit compared to margarines due to the formation of HMF, MDA, GO, and MGO.

Aggregation studies of alpha-lactalbumin induced by edible azo dyes with different sulfonyl group numbers: A comparative study

As an opaque and complex colloidal mixture, milk is usually present as a positively charged colloid under acidic conditions. Adding negatively charged colloids can lead to protein aggregation in milk. Alpha-lactalbumin (α-La) is an essential component of whey protein and has good physicochemical properties for functional food development. We combined spectroscopy, computer simulations, and other techniques to comparative analyze the mechanisms and characteristics of isolated α-La aggregation induced by CI Acid Red 27 (C27)/CI Acid Red 14 (FB) containing different sulfonyl groups in vitro. The results showed that C27/FB (5.25 × 10-5 mol·L-1 to 3.15 × 10-4 mol·L-1) induced the formation of fibril-like aggregates under acidic conditions (pH 2.0 and 4.0) mainly benefit from hydrophobic and electrostatic forces. Weakening and redshift of α-La's characteristics negative peak were observed (208 nm to 218 nm) on circular dichroism. β-Crosslinks self-assembly and reorganization of disulfide bonds occurred during protein fibrillation. Moreover, the different redshift intensity of Congo red binding to amyloid fibrils was observed to be induced by C27 (>551 nm) and FB (>536 nm), and the direct observation by TEM demonstrated the ability to induce protein fibrillation is C27 > FB. Edible azo dyes with more sulfonyl groups would possess a stronger ability to induce protein fibrillation.

Investigation on the Contents of Nε-carboxymethyllysine, Nε-carboxyethyllysine, and N-nitrosamines in Commercial Sausages on the Chinese Market

Sausages are among the most popular meat products worldwide. However, some harmful products, such as advanced glycation end-products (AGEs) and N-nitrosamines (NAs), can be formed simultaneously during sausage processing. In this study, the contents of AGEs, NAs, α-dicarbonyls and the proximate composition were investigated in two kinds of commercial sausages (fermented sausages and cooked sausages) in the Chinese market. The correlations among them were further analyzed. The results showed that the fermented and cooked sausages had different in protein/fat contents and pH/thiobarbituric acid reactive substance values due to their different processing technologies and added ingredients. The N^ε-carboxymethyllysine (CML) and N^ε-carboxyethyllysine (CEL) concentrations varied from 3.67 to 46.11 mg/kg and from 5.89 to 52.32 mg/kg, respectively, and the NAs concentrations ranged from 1.35 to 15.88 µg/kg. The contents of some hazardous compounds, such as CML, N-nitrosodimethylamine, and N-nitrosopiperidine, were observed to be higher in the fermented sausages than in the cooked sausages. Moreover, levels of NAs in some sausage samples exceeded the limit of 10 µg/kg issued by the United States Department of Agriculture, suggesting that particular attention should be paid to mitigating NAs, especially in fermented sausages. The correlation analysis suggested that the levels of AGEs and NAs were not significantly correlated in both kinds of sausages.

Safety and quality assessment of street-vended barbecue chicken samples from Faisalabad, Pakistan

The current study was designed to assess the safety and quality status of street-vended barbecue chicken samples. The samples were collected from four regions of Faisalabad city: Ghulam Mohammad Abad (R₁), Jhang Road (R₂), Sargodha Road (R₃), and Satiana Road (R₄); and compared with the self-prepared barbecue chicken sample (R₀). Purposely, all the collected samples were subjected to assess the quality aspects by physicochemical analyses. The results of the physicochemical analysis showed that moisture content varied from 54% to 60%, crude protein 26.97% to 32.87%, crude fat 7.25% to 9.00%, crude ash 1.61% to 1.72%, pH 5.60 to 6.30, free fatty acid value 1.00% to 1.39%, and peroxide value 0.63 to 0.84 meq/Kg. Results pertaining to the enumeration of total microbial load and total coliform count exhibit 2.39-5.17 and 1.20-3.20 log cfu/g, respectively. The samples were assessed for heavy metals (Pb, Zn, Cd, and Fe) by atomic absorption spectrophotometer (AAS). The concentration of highly toxic metals Pb and Cd was found to be much higher than recommended value as they ranged from 1.90 to 3.70 mg/kg for Pb and 0.10 to 0.90 mg/kg for Cd. However, the level of essential metals (Fe and Zn) in barbecue chicken samples ranged from 67.10 to 180 and 8.30 to 35.80 mg/kg which was much higher than their safe limits for Fe (15 ppm) and Zn (5 ppm), respectively. The study concludes that the consumption of street-vended barbecue chicken possesses to be a serious public health risk for consumers.

Effect of cooking methods on the edible, nutritive qualities and volatile flavor compounds of rabbit meat

BACKGROUND

Rabbit meat is a good edible meat source with high nutritional values. Cooking has a significant impact on the edible properties, nutritional qualities and flavor characteristics of meat. Studying the effect of cooking methods on rabbit meat qualities could encourage more understanding and acceptance of rabbit meat by consumers, and could also provide some reference for rabbit meat processing. Therefore, the effects of boiling, sous-vide cooking, steaming, microwaving, roasting, frying and pressure cooking on the edible, nutritive and volatile qualities of rabbit meat were investigated.

RESULTS

The sous-vide cooked rabbit meat sample showed higher moisture content, water-holding capacity and lower cooking losses than other samples, but the results of roasted rabbit meat sample were the opposite, and scanning electron microscopy observations also verified the results. There was no significant difference in 2-thiobarbituric acid reactive substance (TBARS) value in the cooked samples except for roasting. Microwaving, roasting and frying exhibited stronger antioxidant activity than the other cooked samples after in vitro digestion. A total of 38 volatiles were identified in the cooked meat samples, and the samples were well divided into four groups by principal component analysis, and 13 volatiles were considered discriminatory variables for the cooked rabbit meat.

CONCLUSION

The physicochemical characteristics of cooked meat differed significantly between the processing methods. Roasted meat showed lower TBARS value and stronger antioxidant activity after simulated digestion compared to the other meats. However, pressure cooked meat detected the most volatile components while roasting the least. © 2022 Society of Chemical Industry.

Sous vide processing: a viable approach for the assurance of microbial food safety

As consumer needs change, innovative food processing techniques are being developed that have minimal impact on food quality and ensure its microbiological safety. Sous vide (SV) is an emerging technology of cooking foods in vacuum pouches at specific temperatures, which results in even heat distribution. Presented here is an overview of the current state of the art in the application of SV techniques for processing and preserving foods. Unlike the conventional thermal food processing approach, the precise nature of the SV method improves food quality, nutrition and shelf-life while destroying microorganisms. Foods processed by SV are usually subjected to temperatures between 50 and 100 °C. Although sufficient for food preparation/processing, its effectiveness in eliminating microbial pathogens, including viruses, parasites, vegetative and spore forms of bacteria, is limited. However, the inactivation of spore-forming microbes can be enhanced by combining the technique with other non-thermal methods that exert negligible impact on the nutritional, flavour and sensory characteristics of foods. In addition to exploring the mechanism of action of SV technology, the challenges related to its implementation in the food industry are also discussed. SV method potential, applications, and impacts on spore-forming microbes and spore inactivation are explored in this review. Through the debate and discussion presented, further research and industrial applications of this food processing method could be guided. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Effects of thermal processing on N,N-dimethylpiperidinium (mepiquat) formation in meat and vegetable products

N,N-dimethylpiperidinium (mepiquat) is an important food contaminant formed from natural ingredients during thermal processing. In this study, mepiquat formation in meat (pork and beef) and vegetables (potatoes and broccoli) was investigated via HPLC-MS/MS; the investigated cooking methods were oven baking, pan cooking, deep frying, and microwaving. The results showed that, among all foods, oven-baked potatoes showed the highest mepiquat level of 1064 μg/kg, which appeared after 20 min at 240 °C. The residual rates of mepiquat precursors, pipecolic acid (PipAc), betaine, choline, and trigonelline, were determined in oven-baked potatoes to investigate their correlation with mepiquat formation. The PipAc levels reduced by 99.8% at 260 °C after 30 min of oven baking, exhibiting a significantly high decomposition rate. Therefore, PipAc could be used as a marker of quality for the detection of mepiquat in thermally processed foodstuffs.