Summary Food safety and quality became very important, especially with the challenge to ensure safe and healthy foods in regard to chemical hazards. So, this study was conducted to evaluate the quality and safety of irradiated Ras cheese during the storage period, with respect to biogenic amines (BAs). Ras cheese was manufactured, ripened and irradiated by γ‐irradiation at 0, 5, 10 and 15 kGy. The samples were stored in refrigerator at 5 ± 1 °C from where samples were withdrawn at 0, 2, 4 and 6 months for analysis. The results revealed that most sensory scores and chemical properties showed insignificant differences (P ≤ 0.05). The microbial counts were reduced with different degrees according to both storage period and irradiation dose. Also, irradiation was effective in reducing the content of BAs without harming the chemical properties of Ras cheese. The total content of BAs reflects the safety of irradiated Ras cheese and also indicates a high‐quality product in comparison with nonirradiated samples.

To cite this paper: Sallam, E.M. and M.M. Anwar, 2017. Antioxidant activity of some extracts from gamma irradiated purslane (Portulaca oleracea) plant. AbstractPurslane plant is one of the most used medicinal plant listed in the World Health Organization. This paper aims to evaluate the effect of some solvent and different doses of irradiation on antioxidants level and its activity. The extraction of antioxidants was performed by methanol, ethanol and distilled water. Antioxidant activities were determined by Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing power (FRAP) and β-carotene bleaching (βCB). Results indicated that extraction by methanol (50%) had higher total phenolic contents (TPC) than other extracts. As well as, the total antioxidant contents and its activities increased with increasing the irradiation dose. Extraction of irradiated purslane plant at 9 kGy by methanol (50%) considered the effective one to obtained natural phenolic acid compounds; which were identified by HPLC to twenty four components. Moreover, methanol extracts were tested for their antioxidant activity on sunflower oil. The obtained data showed that all tested parameters had higher in comparison to control. Methanol extracts were also tested for their antimicrobial activity, which showed higher inhibition activity of all micro-organism (Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Klebsiella Pneumonia, Bacillus cereus).

a b s t r a c t This investigation aims to evaluate the effects of g-irradiation on anti-nutritional factors, in-vitro protein digestibility and functional properties of canola meal protein, physicochemical properties and fatty acid composition of canola seed oil. Irradiation at doses 10, 20, 30 KGy had no effects on the chemical composition of canola seed, while decreased the total glucosinolate content by 15.6, 30.4 and 49.4%; and phytic acid by 29, 55 and 100%, respectively. On contrary, in-vitro protein digestibility increased to 59.1, 61.4 and 71.8% by the same doses, respectively. Water absorption and fat absorption increased by increasing irradiation doses, whilst decreased foaming capacity. Refractive index was between 1.4636 and 1.4687, acid value between 0.72 and 1.10%, peroxide value between 3.40 and 7.36 meq/ kg oil. Iodine number and saponification value were 122 and 175 at dose 30 KGy, respectively. Oxidative stability decreased to 17.8, 16.4 and 14.9 h by doses 10, 20 and 30 KGy,respectively, compared to control (18.9 h). The contents of oleic and linoleinic acid were ranged between 60.44e61.69% and 21.72e22.09% respectively. So, g-irradiation considered a safe method which reduced the anti-nutritional factors and improve both nutritional value and functional properties of canola seed.

The present study aims at evaluating antioxidant and antimicrobial activities of olive (Olea europaea) leaves extracts (OLE) obtained from olive leaves (OL) irradiated at the dose levels 5, 10, and 15 kGy. The antioxidant activity of the extracts was estimated using the radical scavenging activity, and ferric reducing antioxidant power. The antimicrobial activity of the extracts was assessed against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa, and Salmonella typhumurium. The results indicated that OLE obtained from irradiated OL at dose of 10 kGy had the highest antioxidant activity and antimicrobial activity. Thus, OLE obtained from OL irradiated at 10 kGy selected to be added to minced beef. The results indicated that when 2 and 3 ml OLE were added to 100 gm of minced beef could improve quality attributes and extend shelf‐life of minced beef from 1 week to 3 and 4 weeks under cold storage. Practical applications Food decay by spoilage, microorganisms, and chemical activates, causes economic losses. Using chemical preservatives, in meat products to control spoilage, microorganisms, and lipid oxidation, is not safe and it could be harmful to human health. So, it is of importance to find natural ingredients to use instead of the chemical preservatives. The OL are considered a natural source of bioactive compounds including antioxidant and antimicrobial ingredients. Also, gamma (γ) irradiation increases the content of bioactive components extract from OL, and increases the antioxidant and antimicrobial activities of OL. Therefore applying extracts from irradiated OL to meat products for retard oxidative fat could improve quality attributes and extend shelf‐life of meat products.

In this paper, gamma-irradiation was successfully used to intensify the yield of Zinc oxide nanoparticles (ZnONPs) produced by the fungus Alternariatenuissima as a sustainable and green process. The obtained data showed that 500 Gy of gamma-irradiation increased ZnONPs’ yield to approximately four-fold. The synthesized ZnONPs were then exploited to develop active Carboxymethyl Cellulose films by casting method at two different concentration of ZnONPs 0.5% and 1.0%. The physicochemical, mechanical, antioxidant, and antimicrobial properties of the prepared films were evaluated. The incorporation of ZnONPs in the Carboxymethyl Cellulose films had significantly decreased solubility (from 78.31% to 66.04% and 59.72%), water vapor permeability (from 0.475 g m−2 to 0.093 g m−2 and 0.026 g m−2), and oxygen transfer rate (from 24.7 × 10–2 to 2.3 × 10–2 and 1.8 × 10–2) of the respective prepared films. Meanwhile, tensile strength (from 183.2 MPa to 203.34 MPa and 235.94 MPa), elongation (from 13.0% to 62.5% and 83.7%), and Yang's modulus (from 325.344 to 1410.0 and 1814.96 MPa) of these films were increased. Moreover, the antioxidant and antimicrobial activities against several human and plant pathogens the prepared of Carboxymethyl Cellulose-ZnONPs films were significantly increased. In conclusion, the prepared Carboxymethyl Cellulose-ZnONPs films showed enhanced activities in comparison with Carboxymethyl Cellulose film without NPs. With these advantages, the fabricated Carboxymethyl Cellulose-ZnONPs films in this study could be effectively utilized as protective edible coating films of food products.

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The aims of this study were to evaluate the nutritional value of new hybrids sweet potato in order to raise public awareness of its potential use in nutrition and to formulate high protein quality weaning foods. The nutritional composition was determined for two new cultivar and local cultivar grown up in Horticulture Institute in El-Qanater El-Khyariya Egypt. The cultivars namely Minufiya 2/96 and Minufiya 9/96 were compared with local cultivar (Mabrouka). The results show that protein contents of new cultivar were greater than that of local cultivar. Protein levels were 9.78, 11.27 and 5.17% for Minufiya 2/96, Minufiya 9/96 and Mabrouka respectively. The new cultivar also were higher than the local cultivar on total carbohydrates, total sugar, reducing sugar, nonreducing sugar and sucrose content .The results revealed that sweet potato might be mentioned as a source of antioxidant (Vitamin C and β-carotene). The concentration of β-carotene mg/100g F.W was 12.64, 10.20 and 6.76 for Minufiya 2/96, Minufiya 9/96 and Mabrouka respectively, and the content of Vit. C was 15.05, 20.47 and 17.59 mg/100g F.W. for Minufiya 2/96, Minufiya 9/96 and Mabrouka respectively. Four weaning food mixture were formulated from sweet potato70%, ficus carica 10% and or peanut and chickpea or mung bean or soybean in the ratio (20%) respectively in the form of powder. Data indicate that these mixtures had higher protein quality and quantity .Formula 1 of weaning food mixture showed high acceptability for appearance, texture, odor, color and taste. Also it is cheap weaning foods, the average cost of 100 gram from .080 to 1.50L.E.

Available online xxxKeywords: Shelf lifeBatte Hydrocolloids Irradiation a b s t r a c t Batte (is baked french) one of the most baked coated most prevalent in the markets after the cake wrapping. Batte exposed generally two types of corruption which is occurring phenomenon of (anti-staling) and corruption microbial (molds). In this study produced batte with an attempt to prolong the period of its validity by addition 1.5% hydrocolloids, (which is 0.5% sodium alginate, 0.5% k-carrageenan and 0.5% hydroxyl propyl methylcellulose) (HPMC) to hard wheat flour 72% (HWF) to improve materials for mellowness and anti-staling, whereas batte exposed to gamma irradiation at doses 0.5, 1, 1.5, 2, 3 and 5 kGy to decrease microbial load. Hydrocolloids at 1.5% improved the rheological properties of dough farinogragh and aextensograph parameters. The hydrocolloids increase flexibility, rubber and freshness of batte to 24 days compared to 8 days in control sample. Thiobarbituric acid (T.B.A) values at the end of storage at room temperature (ranged to 0.253 e0.352 mg malonaldehyde/kg) that were less than these mentioned by the Egyptian Standard. Also, gamma irradiation reduced the total bacterial count of batte product.Sensory evaluation of produced batte was done. The addition of 1.5% hydrocolloids and exposed to gamma irradiation had higher freshness and increase shelf-life for 20, 25, 30, 35 and 40 days against only 15 days for control sample.