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سابقه و هدف: امروزه به دلیل خطرات ناشی از نگهدارنده های شیمیایی در مواد غذایی روشهای جایگزین و بی خطر مانند استفاده از عصاره طبیعی گیاهان طبیعی افزایش یافته است، مطالعه حاضر با هدف بررسی اثرات ضد باکتریایی عصاره میوه کنار بر روی چهار باکتری غذازاد سالمونلا، شیگلا، اشرشیاکلی و باسیلوس سرئوس انجام گرفت.مواد و روش ها : عصاره میوه کنار را به شیوه خیساندن یا غوطه وری در متانول تهیه کردیم.پس از تغلیظ توسط دستگاه روتاری به تهیه 9 غلظت از عصاره به شیوه سریالی پرداختیم، سپس اقدام به آنتی بیوگرام به روش چاهک و تعیین حداقل غلظت ممانعت از رشد1 (MIC) و حداقل غلظت کشندگی2 (MBC) نمودیم. همچنین از محلول حجمی_حجمی متانول و دی متیل سولفوکساید با نسبت برابر به عنوان کنترل منفی و از دیسک های شاهد و استاندارد آنتی بیوتیکهای تجاری به عنوان کنترل مثبت استفاده نمودیم.یافته ها : بر اساس نتایج ، قطر هاله رشد برای شیگلا، سالمونلا، باسیلوس سرئوس و اشرشیاکلی در غلظت mg/mL 80 از عصاره متانولی گیاه کنار به ترتیب 24، 17، 59 و 19 میلیمتر بدست آمد. همچنین مشخص شد عصاره متانولی میوه کنار دارای اثرات ضد باکتریایی بسیار مطلوبی بر باکتری گرم مثبت باسیلوس سرئوس نسبت به سایر باکتری های هدف(که گرم منفی هستند) بوده و دارای اثرات مهار از رشد و باکتری کشی قابل توجهی در غلظت های بسیار کم بود. نتیجه گیری: نتایج نشان داد که عصاره متانولی کنار دارای تأثیرات ضد باکتریایی بسیار مطلوب بر علیه چهار باکتری هدف بوده است. ازاینرو می‌توان گفت که احتمالاً ترکیبات تشکیل دهنده عصاره متانولی این گیاه می‌تواند به عنوان اجزاء مهم سازنده محصولات مختلف در صنایع غذایی، دارویی، آرایشی و بهداشتی مورد استفاده قرار گیرند.

Nowadays, the food industry is looking for new technologies to increase the shelf life of various products. Furthermore, as consumer's demand for more “healthier” meals (free of conventional chemical preservatives) has increased in the last decade. In this study, edible sago starch coating containing leave extract of Withania Somnifera (0.125 and 0.25 mg/ml, 1 and 2 times MIC, respectively) was applied onto chicken fillet to extend its shelf life at 4 ̊C. Examination of coated chicken fillets showed that active film of sago starch inhibited the microbial load (aerobic bacteria, coliform and Staphylococcus aureus bacteria) of chicken fillets. The results of chemical analysis of chicken fillet also showed that the coated samples had less volatile nitrogen compounds, thiobarbituric acid index and peroxide value than control. In general, the results of this study showed that the edible film produced from sago starch containing Withania Somnifera extract increases the shelf life of chicken fillets. [ABSTRACT FROM AUTHOR]

In this study, the effect of various concentrations (0, 50 and 100%) of date syrup on quality characteristics of dairy dessert was evaluated. Properties of dairy dessert such as pH, acidity, rheological properties, sensory properties and viability of probiotics in 5 ˚c were determined. Results showed that by increasing date syrup concentration and amount of probiotic bacteria, pH decreased and as the storage progressed significant trend in the pH was observed for all treatments. Studied treatments had statistically effect on viscosity. Addition of date syrup decreased apparent viscosity, consistency coefficient and increased flow behavior index. The most and lowest viscosity was observed in control (1364.1 mPa.s) and 100% date syrup treatments (599 mPa.s), respectively. Sensory properties were affected by date syrup concentrations. Treatment with 50% date syrup had higher scores than others. The number of viable cells of probiotic bacteria was reduced significantly during storage period. The lowest and highest of viability of probiotic bacterial was observed in 100 and 50 % date syrup treatments, respectively. The results suggest that using of date syrup at concentrations of 50% improve sensory and physical properties and can increase viability of probiotic bacteria of dairy dessert samples. [ABSTRACT FROM AUTHOR]

Nowadays, extensive investigations have been conducted on developing novel biopolymers from biodegradable sources. In the current study, the active packaging film based on sago starchcontainingvarying concentrations (1, 1.5 and 2 MIC) of Withania SomniferaL. extract were produced. The Minimal Inhibitory Concentration (MIC) and Minimal Bactericide Concentration (MBC) of extract were measured. Physicochemical (such as thickness, water absorption capacity (WAC), water solubility (WS), water vapor permeability, Oxygen Permeability (OP) and contact angle (CA)), mechanical (tensile strength, elongation to break and modulus of elasticity) and antioxidant properties of the films were evaluated. The antibacterial activity of the films also was tested against two common food-borne pathogens (Escherichia coli, and Staphylococcus aureus) by the disc diffusion method. The results showed that increasing concentrations of Withania SomniferaL. extract have a significant effect (p <0.05) to increase the amount of thickness, WS, water vapor permeability, OP, and CA, but was not effective on WAC.Withania SomniferaL. extract increased the absorption of color in the visible region, which in turn led to an increasing of the parameters a* (index color tends toward green) and b* (index color tends towards yellow) but reduced L* .An increase in Withania SomniferaL. extract content resulted in a plasticizing effect, reducing the tensile strength and Young’s modulus but a concurrent increase in elongation at break. Sago films containing higher percentagesof Withania SomniferaL. extract were effective against all two tested bacterial strains, and these effects were more significant in the case of the gram-positive bacteria. Sago film containing extractshowed a good DPPH radical scavenging activity. These results suggest that the developed sago films containingWithania SomniferaL. extract could be used in various food packaging applications. [ABSTRACT FROM AUTHOR]