Assessment of the Effect of Secondary Fixation on the Structure of Meat Products Prepared for Scanning Electron Microscopy

Abstract

The aim of the research was to verify the necessity of secondary fixation with osmium tetroxide in various types of meat products and evaluation of structural changes of products using different fixation procedures. The material for the study consisted of 11 types of meat products that were analyzed using a scanning electron microscope (SEM) with two different methods of chemical fixation. The first method included the usual processing of biological samples: glutaraldehyde primary fixation, the use of a buffer, secondary fixation by osmium tetroxide (OsO4), buffer, and dehydration using ethanol of increasing concentrations. The second method comprised the glutaraldehyde primary fixation and dehydration using the ethanol of increasing concentrations only. The results unambiguously suggest that the main difference between these methods is in fixation and visibility of fat. Our analysis principally suggests that fixation of the product with OsO4 allows the tracking of all components (fat droplets, muscle fibers, connective tissue) in meat products. At the same time, our results also support the possibility that the secondary fixation can be skipped during the analysis, where the main objection is an observation of lipid-free structures of the meat products (e.g., connection between muscle and starches or spices) or meat products with an insignificant amount of fat.

Fatty acid composition, oxidative stability, and sensory evaluation of the sausages produced from the meat of pigs fed a diet enriched with 8% of fish oil

“…According to Běhalová et al. (2020), a presence of a less viscous form of fat (e.g., LC‐PUFA n‐3 in the present study) may be more noticeable in sausages with a paste‐like structure (in our case V‐sausages) than in salami (B‐salami in the present study).…”

“…The second reason could be the lower ratio of the lean to fatty meat in the V-sausages (33% : 40%) in comparison with the B-salami (43%:37%). According to Běhalová et al (2020), a presence of a less viscous form of fat (e.g., LC-PUFA n-3 in the present study) may be more noticeable in sausages with a paste-like structure (in our case V-sausages) than in salami (B-salami in the present study).…”

Development of Drying Methodology for Intact Whole Buffalo Liver, Its Characterization, Shelf Life, and Evaluation of Palatability as Pet Treat

“…The microstructure analysis of fresh and dried buffalo liver samples was analysed using a scanning electron microscope (Cube-II, EMCRAFTS, Gyeonggi-do (12814), Republic of Korea). The samples were processed according to Běhalová et al [35] with slight changes. The samples were cut in the dimension of 1 mm thickness, 1 cm length, and 0.5 cm breadth followed by overnight fixation in 10% formaldehyde.…”

Effect of Slightly Acidic Electrolyzed Water Immersion at Different Frequencies on Quality of Raw Chicken Legs

“…Before analysis, chicken meat was fixed with 2.5% glutaraldehyde in a phosphate-buffered solution (pH 7.2-7.4) and rinsed 2 times with distilled water for 10 min. After fixation, the meat samples were serially dehydrated by immersion in ethanol (25, 50, 70, 80, 90, and 99%) for 30 min, snap-frozen in liquid nitrogen, and dried using a freeze-dryer for 2 days [18][19][20]. The samples were examined and photographed under a scanning electron microscope (TM4000; Hitachi) at 5 kV voltage and 100× magnification.…”