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This study aimed to determine the effect of ultrasonication (US) and vacuum impregnation (VI) pretreatment techniques applied for the improvement of tenderness on the quality of beef ( Longissimus dorsi) traditionally marinated (TM) in onion juice by immersion. TM conditions were 1:5 meat to marinade ratio, final NaCl concentration of 9% (w/v), 4.3 °C and 24 h. US and VI pretreatments significantly ( P < 0.05) improved the marinade uptake, but did not alter the lightness (L*) values of beef samples compared to TM. US for 60 min and VI for 40 min pretreatments reduced the hardness of beef by 28.25 and 21.62%, respectively, compared to TM. US and VI pretreatments significantly ( P < 0.05) reduced tyramine levels of uncooked and marinated beef samples. Marination in onion juice was found to reduce the lipid oxidation level of beef and increase the general liking score in the sensorial evaluation. Onion juice can be used as a natural marinade for the traditional marination of beef with the help of ultrasonication and vacuum impregnation pretreatments.

In this study, effects of novel casing, antimicrobials (chitosan and AgZeo) incorporated into multilayer polyethylene casing, on chemical and microbial attributes of sucuks were followed through 3 days of fermentation and 12 days of storage after heat treatment. Microbial growth was reduced by chitosan incorporated casing. Aerobic plate count (APC) of 8.81 log CFU g-1 on the 3 rd day of fermentation was reduced to 2.60 log CFU g-1 by the end of storage. APC and lactic acid bacteria (LAB) were decreased signifi cantly (P<0.05) by antimicrobial casings. The lowest concentrations of histamine and tyramine were observed (P<0.05) in sucuks stuffed into chitosan incorporated casing. These results show that antimicrobial casing could be used in sucuk production to improve its safety and quality.

Mushrooms can be native, less handled and readily present source of natural antioxidants. In this study, dried Agaricus bisporus and Pleurotus ostreatus were extracted with 80 % methanol, ethanol and acetone seperately. Total phenolics and antioxidant acitivities of extracts were determined by Folin-Ciocalteu method and DPPH and FRAP methods, respectively.The highest total phenolic contents were 31727 mg GAE (on d.b.), 33201 mg GAE (on d.b.) in methanolic extract of non-dried A. bisphorus and P. ostreatus respectively. The percentage of the DPPH radical-scavenging activity (DPPH-RSA) of dried P. ostreatus was 98% (on d.b.) in methanolic extract. Ferric reducing antioxidant power of dried P. ostreatus had highest level (0.35 mM Trolox, on d.b.) in methanol extraction. Total phenolic compounds and antioxidant acitivities were not affected by microwave power and conventional drying temperature.