Marjoram was applied to beef burger to improve its physical and chemical properties and to extend its shelf life. Marjoram was added to beef burger in two forms; ethanolic extract at 0.1, 0.2 and 0.3 g/100g and as dry powder at 0.2, 0.4 and 0.6 g/100g and was stored at freezer (-18℃) for three months. Chemical properties including moisture, protein, fat contents and pH values, physical properties (water holding capacity), cooking characteristics (shrinkage, cooking loss and cooking yield), shelf life limiting parameters (TBA, TVN and total plate count) and sensory evaluation test were all investigated. Moisture, protein and water holding capacity increased in both additives (marjoram extract and marjoram powder) added to the burger recipe and these parameters decreased at the end of storage period while fat increased with additives and after storage. All cooking parameters improved as shrinkage and cooking loss decreased with marjoram addition while cooking yield increased. TBA, TVN and total plate count at all added marjoram samples were lower than control at zero time and increased through time in all samples but marjoram added beef burger samples showed less increase rate comparing to that of control. Sensory evaluation test showed that marjoram ethanolic extract and powder did not alter sensory parameters make marjoram a potential application in beef burger.

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The effect of ozone gas on mold and aflatoxin production in wheat grains imported from Argentine, Germany, Ukrainian, Australia and U.S.A and Egyptian wheat grains (Gamaza 7) were investigated. The treatment of wheat grains directly with ozone gas for 5 and 6 hours, the growth of Aspergillus flavaus was completely inhibited and consequently the total aflatoxin content was decreased. Cylinders of milling were found to be sources of fungal species pollution, total mould count and Aflatoxin production. The results suggest the use of ozone gas treatment for preservation of wheat grains during storage.

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The current study was carried out to evaluate the use of crude isoflavones (CIE), crude rosemary extract (CRE), butylated hydroxy anisol (BHA) and CIE plus CRE, as antioxidant and antimicrobial agents in manufacture of beef burgers during frozen storage at -18ºC for three monthes. The antioxidant and antimicrobial effects of the CIE, CRE, BHA and CIE plus CRE, were evaluated in beef burger by measuring pH, tiobarbituric Acid (TBARS) values, unsaponifiable matter, texture profile, sensory and microbiological examinations. The results showed that extracts derived from soybean (CIE) and rosmary (CRE) leaves had the potential to reduce the oxidation of beef burgers and extend their shelf life. The combination composed of 0.03% of CIE and 0.06% of CRE provided the most effective antioxidative activity in terms of TBARS values until the latter stages of storage. The combined extracts showed good antibacterial activity againist total bacterial count, coliform, staphylococous and E. coil that led also to enhance extension of beef burger shelf life. The availability of these natural antioxidants and their possible synergistic effects suggests an interesting way of improving beef burger stability to prevent the degenerative diseases caused by fat oxidation products.