Improvement of oxidative stability and textural properties of fermented sausage via addition of pistachio hull extract.

The purpose of this study was to evaluate the effectiveness of pistachio hull extract (PHE) as an antioxidant and antimicrobial agent for preservation of dry fermented sausages during fermentation and storage period. Sausages were prepared using starter culture (Biobak K) and treated with three levels of PHE (500, 750 and 1,000 ppm). The results showed that PHE at concentrations of 500 ppm and 750 ppm decreased significantly (p < .05) the TBARS content of the sausage samples compared to control (without PHE). Moreover, PHE increased L* and a* value of samples during fermentation period but did not affect the color of samples during storage period. The PHE was also able to improve the chewiness and gumminess of the fermented sausage. Evaluation of microbial properties (total viable count, yeast and molds, lactic acid bacteria, staphylococci and Enterobacteriaceae) also showed that antimicrobial activity of PHE in fermented sausage.

Application of Zataria multiflora Boiss. and Cinnamon zeylanicum essential oils as two natural preservatives in cake.

OBJECTIVE: Oxidation of oils has an important effect on nutritional and organoleptic properties of foodstuffs. Nowadays, new tendency has created a necessity to use natural compounds such as essential oils for producing functional foods. In this study, antioxidant, antifungal, and organoleptic properties of Zataria multiflora Boiss. (ZMEO) and Cinnamon zeylanicum essential oils (CZEO) have been checked as two natural preservatives in the cakes. MATERIALS AND METHODS: The antioxidant activity of essential oils were determined by measuring thiobarbituric, peroxide, and free fatty acid values of prepared cakes during 60 days storage at 25 ˚C. Antifungal properties of essential oils were determined and given as the ratio of colony number in samples containing ZMEO and CZEO to the control. RESULTS: Different concentrations of essential oils prevented oxidation rate and reducd preliminary and secondary oxidation products compared with butylate hydroxyanisole (BHA (100 and 200 ppm)) and control cakes. Moreover, ZMEO and CZEO at three concentrations (500, 1000, and 1500 ppm) reduced the fungal growth more than samples containing BHA (100 and 200 ppm) and the control. CONCLUSION: Our results showed that optimum concenteration of ZMEO and CZEO for using in the cakes was 500 ppm therefore it can be replaced instead of synthetic preservatives in foodstuffs.