Lipid oxidation of beef fillets during braising with different cooking oils

Effect of Heating under Different Vacuum Levels on Physicochemical and Oxidative Properties of Beef Sirloin

The physicochemical and oxidative properties of beef sirloin slices heated under atmospheric (101.33 kPa, a vacuum percent of 0%, control) and vacuum (50.8 kPa, 50% and 7.2 Pa, 99.99%) conditions by using an airtight vacuum container were compared. Heating at a higher vacuum level resulted in the lowest pH and cooking loss compared with the other conditions (p < 0.05). The beef in vacuum groups was less hard, chewy, and gummy than the control group, without any significant differences between the vacuum groups. More structural shrinkage and lower browning were observed in the meat heated at higher vacuum levels. Similarly, higher vacuum levels suppressed increases in the lightness (L*), redness (a*), and total color difference (E*) of the surface after heating. The thiobarbituric acid (TBA) values, a sensitive indicator of meat oxidation due to heating, were only influenced by the vacuum conditions. Consequently, applying a vacuum effectively prevents the degradation in the meat’s physicochemical and oxidative properties during heating. The findings are useful for the sous-vide industry because they scientifically demonstrate how vacuum pressure affects the physicochemical and oxidative properties of the meat by using a specially designed airtight vacuum container.

Fatty acid composition and oxidation in beef muscles as affected by ageing times and cooking methods

This study aimed to determine how ageing and cooking, each one applied to the beef meat most suitable (pan-fried or grilled ribeye steak, braised chuck and fried or roasted rump steak), induce changes in lipid content, fatty acid (FA) composition and lipid oxidation of muscles from 16 cattle representative of animals raised for France meat production. The fattiest muscle (ribeye) was the richest in saturated and monounsaturated FA leading to poor nutritional indexes. In contrast, the leanest muscle (rump) had the highest proportion of polyunsaturated FA and the highest levels of peroxidation without exceeding critical limits. The impact of cooking methods seemed mainly linked to the moisture loss increasing meat fat content and the culinary fat addition whose FA composition marked the meat. Cooking methods induced oxidation phenomena that could exceed the limit thresholds. In conclusion, short cooking time of rump steak was the best combination to meet nutritional expectations.

Oxidative stability of gelatin coated pork at refrigerated storage

As consumers are chiefly concerned with odor and appearance, refrigerated meats have a greater possibility of rejection due to their perishability. A treatment was designed to preserve the quality parameters such as color and oxidation rate. The treatment encompassed coating pork loin samples with aqueous porcine gelatin solutions (175 bloom) at three concentrations (0%, 10% and 20%) and studying its effect on lipid oxidation, protein oxidation, oxidation pre-cursors, color and purge of meat. Vacuum packed Longissimus dorsi muscle was cut into 10 x 5 x 1 cm samples and randomly dipped in one of three solutions. Samples were stored at 4 degrees C and analyzed for thio-barbituric acid reactive substances, metmyoglobin content, protein carbonyls, heme iron content and color change. There was a significant difference (p<0.05) for TBARS values, protein carbonyls, heme iron content, total color change, metmyoglobin content with treatments maintaining values more similar to a fresher product when compared to control on days 3, 5 and 7. There was no significant difference (p>0.05) between 10% and 20% gelatin coating on any of the parameters between storage days.

Effect of different cooking methods on lipid oxidation and formation of free cholesterol oxidation products (COPs) in Latissimus dorsi muscle of Iberian pigs

The aim of this work was to study the influence of different cooking methods (grilled (GR), fried (FP), microwave (MW) and roasted (RO)) on lipid oxidation and formation of free cholesterol oxidation products (COPs) of meat from Iberian pigs that have been fed on an intensive system. Moisture and total lipid content, TBARs, hexanal and COPs were measured in Latissimus dorsi muscle samples. Cooking did not produce changes in total lipid content in meat but induced significantly higher lipid oxidation (TBARs and hexanal values) (p<0.001) and cholesterol oxidation (COPs) (p<0.01). When the different cooking methods were studied, the grilled method was the least affected by lipid oxidation (TBARs and hexanal) compared to the others. There were no significant differences among different cooking methods on COPs values. The most abundant cholesterol oxides were both 7α-hydroxycholesterol and 7β-hydroxycholesterol in all groups studied.