ارزیابی روش‌های کمی و کیفی تشخیص سود سوزآور در شیر

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد گروه علوم و صنایع غذایی واحد ورامین- پیشوا، دانشگاه ازاد اسلامی، ورامین، ایران

2 استاد دانشکده دامپزشکی، دانشگاه تهران، تهران، ایران

3 دانشیار گروه علوم و صنایع غذایی، واحد ورامین – پیشوا، دانشگاه آزاد اسلامی، ورامین، ایران

چکیده

هدف از این تحقیق دست­یابی به یک روش سریع و ساده برای تشخیص کمی و کیفی سود افزوده شده به شیر حتی در مقادیر بسیار اندک است. زیرا روش­های آزمون موجود در شرایط عملی و واقعی کاربردی ندارند.بدین منظور نمونه شیر خام بعد از تعیین ویژگی‌های میکروبی و شیمیایی آن به 4 قسمت تقسیم و به هر قسمت مقادیر مختلف اسید لاکتیک اضافه شد و مقادیر مختلف سود به نمونه­ها اضافه گردید. آزمون­های اسیدیته،pH، هدایت الکتریکی، الکل،خاکستر و رزالیک­اسید انجام شد. طبق نتایج با افزایش مقادیر سود، هدایت الکتریکی و خاکستر کل افزایش و اسیدیته کاهش یافت. بین میزان سود اضافه شده به نمونه­ها و pH همبستگی معنی­دار وجود نداشت. آزمون الکل در تمام نمونه­ها نتایج یکسان داشت. آزمون رزالیک­اسید در تمام نمونه­ها منفی بود. در مورد خاکستر قلیایی در هیچکدام از نمونه­ها حجم اسید کلریدریک مصرفی به 2/1 میلی‌لیتر نرسید. با توجه به نتایج، آزمون رزالیک­اسید کارایی لازم را نداشت. آزمون خاکستر قلیایی، مقادیر کمی میزان سود را مشخص نکرد. تنها آزمون هدایت الکتریکی نتایج مثبت و قابل استنادی را نشان داد که می­توان جهت تشخیص و تعیین مقدار سود اضافه شده از آن بهره جست.

کلیدواژه‌ها


عنوان مقاله [English]

Evaluation of qualitative and quantitative methods for detection of NaOH in milk

نویسندگان [English]

  • S. Ardalan 1
  • G. karim 2
  • R. pourahmad 3
1 Graduate, Dep., Food Science and Technology, Varamin-pishva Branch, Islamic Azad University, Varamin, Iran
2 Professor, Dep., Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, Iran
3 Associate Professor, Dep., Food Science and Technology, Varamin-pishva Branch, Islamic Azad University, Varamin, Iran
چکیده [English]

The aim of this study was to achieve a quick and simple quantitative and qualitative method to detect even the trace amount of added soda in raw milk, since the existing tests methods are not applied in practical and real terms. For this purpose, after determining the microbiological and chemical characteristics of the raw milk, the samples were divided into 4 groups. Each group was added by different values of lactic acid, and then different rates of soda were added to the samples. Tests for acidity, pH value, electrical conductivity, alcohol, ash and Rosalic acid were conducted. According to the results with increasing the amount of soda, the electrical conductivity and total ash were increased, however the acidity was decreased. No significant correlation was observed between the added soda and pH value. Alcohol test had the same results on all samples. Rosalic acid test was negative in all treatments. In the case of alkaline ash, in none of the samples the volume of hydrochloric acid consumed reached to 1.2 ml. It was concluded that Rosalic acid test did not work for the detection of soda in raw milk; in addition alkaline ash test did not specify the small amounts of soda. Among the various tests electrical conductivity assay was found to be credible and could be used to detect and quantify the added soda in raw milk.

کلیدواژه‌ها [English]

  • Milk
  • Adulteration
  • Electrical Conductivity
  • Measurement of caustic soda
 

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