Dry Fermented Sausages with Total Replacement of Fat by Extra Virgin Olive Oil Emulsion and Indigenous Lactic Acid Bacteria

Application of chitosan films incorporated with Zanthoxylum limonella essential oil for extending shelf life of pork

This study aimed to produce chitosan films incorporated with Zanthoxylum limonella essential oil for extending shelf life. The volatile compounds of Z. limonella essential oil were identified by gas chromatography-mass spectrometry consisting of limonene, α-phellandrene, ρ-cymene, and sabinene as major compounds. In this study, the addition of Z. limonella essential oil at concentrations of 0 %, 2 %, and 4 % in chitosan film was assessed for its antibacterial activity against Escherichia coli and Staphylococcus aureus. Chitosan film incorporated with 4 % essential oil demonstrated the most significant antibacterial effect against E. coli and S. aureus in comparison to the chitosan film without essential oil due to the synergistic effects on antibacterial activity. The physical and mechanical properties of the chitosan films incorporated with Z. limonella oil developed were also assessed. The addition of essential oil to chitosan films led to improvements in mechanical strength and flexibility, while minimal changes were observed in terms of water solubility, water vapor permeability, and thermal stability. The findings emphasize that this innovative film not only extends the shelf life of pork without chemical preservatives but is also a fully bio-based material. Consequently, it shows great potential to be used as active packaging within the food industry.

Use of mid-infrared spectroscopy for quality monitoring and the prediction of physicochemical parameters of dry fermented chicken sausages enriched with sesame flour

BACKGROUND

This study aimed to investigate the effects of the supplementation of sesame flour in fermented chicken sausages ('S1' containing 800 g kg^-1 chicken fillet, 180 g kg^-1 veal fat and 20 g kg^-1 sesame flour and 'S2' containing 800 g kg^-1 chicken fillet, 160 g kg^-1 veal fat and 40 g kg^-1 sesame flour) compared with control sausages (containing 800 g kg^-1 chicken fillet and 200 g kg^-1 veal fat) on the physico-chemical characteristics, texture, and structure during the fermentation stage.

RESULTS

The physicochemical parameters of samples belonging to the control, S1, and S2 batches were significantly affected by the addition of sesame flour and the fermentation stage. For instance: (i) the lowest protein content was observed for control samples on day 1 (61.4 ± 6.52 g kg^-1 ) whereas the highest level was noted for S2 samples on day 15 (327.5 ± 22.2 g kg^-1 ), and (ii) an inverse trend was observed for the fat content because the lowest content was observed for samples in the S2 batch on day 1 (129.0 ± 5.30 g kg^-1 ) whereas the highest fat content was noted for samples belonging to control batch on day 15 (332.0 ± 1.29 g kg^-1 ). The application of statistical methods to mid-infrared spectroscopy allowed clear discrimination between control, S1, and S2 batches. The addition of sesame flour in the recipes induced some modification in the secondary structure because β-turn levels ranged from 39.30 to 34.50, 36.76 to 34.70, and 38.93 to 34.70 for control, S1, and S2 batches, respectively, throughout the fermentation stage. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed a similar protein profile pattern in the three batches on days 1 and 5, but on day 10 control and S2 batches showed the most intense degradation of myofibrillar proteins.

CONCLUSION

The results demonstrated that mid-infrared spectroscopy coupled with chemometric tools could be used as a rapid screening tool to assess and monitor the quality of dry chicken sausages enriched with sesame flour throughout the fermentation stage. © 2022 Society of Chemical Industry.

Substituting Fat with Olive Oil, Mash Potato, or a Gelatin Matrix in Low-Salt-Content Dry-Fermented Sausages

It was investigated whether physicochemical properties and consumer perception of dry-fermented sausages were affected by the partial replacement of fat and salt by other compounds. A control batch and nine experimental batches, following 3 × 3 factorial design, were manufactured. The NaCl was replaced with of calcium lactate, magnesium chloride, or a blend 85% NaCl (sodium chloride) and 15% KCl (potassium chloride). The fat was partially substituted by olive oil, potato puree, or commercial gelatin. The pH, dry matter, fat content, free fatty acid content, peroxide index, microbial analysis, and tasting, were measured. Both fat type and slat type were affected to measured variables. In terms of moisture, gelatin would be the most recommendable substitute for fat, whereas KCL would be the better substitute for salt. The three oil batches and the potato-magnesium batches presented lower fat content than the control batch. Both the free fatty acid content and the peroxide values increased over the ripening time. At the end of the ripening, the three oil batches presented the highest values for free fatty acids, but there were no differences among the batches of peroxide index. Regarding bacterial counts, the potato-KCL batch was the most like the control batch. In visual appraisal, none of the scores of the measured variables were affected by the batch. Nevertheless, the batch of oil-magnesium would be purchased less than expected. The tasting quality was affected only by the salt type, but all of the batches were different from the control. Neither the gender (p > 0.05) nor the age (p > 0.05) of the respondents affected the taste scores, visual appraisal, or purchase intent. Results shows that the partial substitution of fat and salt in dry-fermented sausages is possible, even in greater percentages than those stated in the literature, without a detriment of sensory properties. Nevertheless, further experiments would be necessary to adjust the formulation, as well as to explore other possibilities.