Comparing the Effects of Thyme (Zataria multiflora) and Rosemary (Rosmarinus officinalis) Essential Oils on Microbiological, Physicochemical, and Sensory Properties of Vacuum-Packaged and Refrigerated Chicken Breast

This study aimed to compare the effects of thyme and rosemary essential oils (EOs) with vacuum packaging on shelf life extension and organoleptic properties of chicken breast meat. For this purpose, two concentrations of 0.1% and 0.3% (v/w) from thyme and rosemary EOs were added individually to fresh chicken breast samples, packed under vacuum conditions, and stored at 4°C for 12 days. All the samples were evaluated for microbiological, physicochemical, and sensory properties at 3-day intervals. The results showed that the thyme EO treatments, especially at 0.3% concentration, significantly reduced both total and psychrotrophic colony counts, and they were more effective in reducing microbial counts compared to rosemary EO treatments. Moreover, thyme EO significantly controlled Escherichia coli growth in treated samples. TBA values in treated samples with thyme EOs were significantly less than in rosemary EOs and control samples. Results indicated that rosemary EO treatments had the lowest pH during 12 days. Colorimetric and organoleptic analysis of the samples showed statistical differences on various days. In the EOs-treated chicken breasts, the color and texture of the samples improved compared to controls, but the taste and odor were not desired at the higher concentration of thyme and rosemary EOs.

Peanut and linseed oil emulsion gels as potential fat replacer in emulsified sausages

The study aimed to highlight the utilization of gelled emulsion (GE) systems containing peanut and linseed oils to replace beef fat partially or completely in emulsified sausages. Total fat content was reduced by up to 40% and energy content was lowered by up to 27% in reformulated products. Saturated fatty acids and cholesterol were successfully decreased while noticeable increments were provided in mono and poly-unsaturated fatty acids in sausages containing GE. Moreover, the reformulation procedure presented a good potential for increasing n-3 content, while lowering atherogenicity index, thrombogenicity index, and n-6/n-3 ratios. Although the incorporated GE resulted in color and texture alterations, it was effective to improve the technological attributes in terms of emulsion stability and cooking behaviors. In GE added samples, oxidative stability of final products decreased; however sensory features were acceptable. Overall results pointed out that GE systems could be successfully conveyed to emulsified sausage formulations to ensure a healthier lipid profile with good technological and sensory quality.

Antioxidant activity of carnosic acid and rosmarinic acid in raw and cooked ground chicken patties

BACKGROUND

Carnosic acid (CA) and rosmarinic acid (RA) are potent antioxidants. The effectiveness of an antioxidant in a food system is dependent on a range of factors such as concentration, phenolic content, physical state of the substrate, processing and storage. However, the antioxidant activity of powder vs liquid and higher vs lower phenols is not clear in different matrices. In this study, OxiKan-WS4 (4.0% RA), OxiKan-S10 (10% CA) and OxiKan-R8 (8% CA) were investigated against lipid oxidation in raw and cooked ground chicken patties during refrigerated storage.

RESULTS

OxiKan-WS4 had the highest (P < 0.05) total phenolic content, whereas OxiKan-S10 and OxiKan-R8 exhibited higher DPPH radical-scavenging activity and reducing power relative to OxiKan-WS4. Lipid oxidation was minimized in meat with added extracts, as indicated by lower (P < 0.05) thiobarbituric acid-reactive substances, peroxide value and free fatty acid. Addition of natural antioxidant extracts at 10 mg equivalent total phenols per 100 g meat did not affect the sensory scores relative to non-treated controls.

CONCLUSION

This study demonstrates that the physical state (powder vs liquid) of CA or RA plays an important role in determining their antioxidant efficacy.