Evaluation of qualitative and quantitative methods for detection of NaOH in milk
Subject Areas : Food Science and Technology
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
Keywords: Milk, Adulteration, Electrical Conductivity, Measurement of caustic soda,
Abstract :
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.
● Institute of Standards and Industrial Research of Iran. (1992). The Method of Measuring Milk Fat. 3nd Revision, ISIRI No. 366. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2002) Milk and Its Products – Microbiology Features. 2nd Revision, ISIRI No. 2406. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2003). Alcohol Test. 2nd Revision, ISIRI No. 1528. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2006). Milk and its products, the method for determining total acidity and pH. 3nd Revision, ISIRI No. 2852. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2014). Milk: Detection and Measurement of Neutralizing Bicarbonate and Sodium Hydroxide. 1nd Revision, ISIRI No. 19700. [In Persian]
● Karim, G. and Tabari, M. (2006) The relationship between electrical conductivity and pH, the acidity and total microbial count in raw milk, Journal of Food Science and Technology, 3(4): 24-36. [In Persian]
● Karim, G., Mohammadi, K., Khandaghi, J. and Karimi Darre Abbi, H. (2011). Testing of milk and its products. The second edition, Tehran University Press. (2th Edition), pp. 107-158. [In Persian]
● Karim, G. (2013). Health and Milk Technology. 3nd Edition, Tehran University Press, pp. 7-26. [In Persian]
● Gelains, D.I. and Champagne, C.K. (1995.) The use of electrical conductivity to follow acidification of dairy blends. International Dairy Journal, 5(2): 427-438.
● Kaptan, B., Kayrsoglu, S. and Demirci, M.A. (2011). The Relationship between some physico-chemical, microbiological, characteristics and electrical conductivity of milk stored at different. Journal of Tekirdag Agricultural Faculty, 8(5): 13-21.
● Lawton, B.A. and Pethig, R.K. (1993). Determining the fat content of milk and cream using EC conductivity measurements. Measurement Science and Technology, 4(9): 38-41.
● Mabrook, M.D. and Petty, M.F. (2003a). A novel technique for the detection of added water to full fat milk using single frequency admittance measurement. Journal of Food Engineering, 69(4): 415-418.
● Mabrook, M.D. and Petty, M.F. (2003b). Effect of composition on the electrical conductivity of milk. Journal of Food Engineering, 69(8): 321-325.
● Paqurt, Y.C. (2000). Electrical conductivity as a tool for analyzing fermentation processes for production of cheese starters. International Dairy Journal, 55(4): 391-399.
● Sadat, A., Mustajab, P. and Khan, A.R. (2006). Determining the adulteration of natural milk with synthetic milk using AC conductance measurement. Journal of Food Engineering, 77(9): 472-411.
● Shweizer, S., Vaihinger, W. and Gupel, F. (1994). Characterization of Food Freshness with Sensor Arrays. 2nd Edition, pp. 87-90.
● Zhung, W. and Zhou, W .(1997) Determination of protein content of whey powder using electrical conductivity measurement. International Dairy Journal, 7(10): 647-653.
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● Institute of Standards and Industrial Research of Iran. (1992). The Method of Measuring Milk Fat. 3nd Revision, ISIRI No. 366. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2002) Milk and Its Products – Microbiology Features. 2nd Revision, ISIRI No. 2406. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2003). Alcohol Test. 2nd Revision, ISIRI No. 1528. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2006). Milk and its products, the method for determining total acidity and pH. 3nd Revision, ISIRI No. 2852. [In Persian]
● Institute of Standards and Industrial Research of Iran. (2014). Milk: Detection and Measurement of Neutralizing Bicarbonate and Sodium Hydroxide. 1nd Revision, ISIRI No. 19700. [In Persian]
● Karim, G. and Tabari, M. (2006) The relationship between electrical conductivity and pH, the acidity and total microbial count in raw milk, Journal of Food Science and Technology, 3(4): 24-36. [In Persian]
● Karim, G., Mohammadi, K., Khandaghi, J. and Karimi Darre Abbi, H. (2011). Testing of milk and its products. The second edition, Tehran University Press. (2th Edition), pp. 107-158. [In Persian]
● Karim, G. (2013). Health and Milk Technology. 3nd Edition, Tehran University Press, pp. 7-26. [In Persian]
● Gelains, D.I. and Champagne, C.K. (1995.) The use of electrical conductivity to follow acidification of dairy blends. International Dairy Journal, 5(2): 427-438.
● Kaptan, B., Kayrsoglu, S. and Demirci, M.A. (2011). The Relationship between some physico-chemical, microbiological, characteristics and electrical conductivity of milk stored at different. Journal of Tekirdag Agricultural Faculty, 8(5): 13-21.
● Lawton, B.A. and Pethig, R.K. (1993). Determining the fat content of milk and cream using EC conductivity measurements. Measurement Science and Technology, 4(9): 38-41.
● Mabrook, M.D. and Petty, M.F. (2003a). A novel technique for the detection of added water to full fat milk using single frequency admittance measurement. Journal of Food Engineering, 69(4): 415-418.
● Mabrook, M.D. and Petty, M.F. (2003b). Effect of composition on the electrical conductivity of milk. Journal of Food Engineering, 69(8): 321-325.
● Paqurt, Y.C. (2000). Electrical conductivity as a tool for analyzing fermentation processes for production of cheese starters. International Dairy Journal, 55(4): 391-399.
● Sadat, A., Mustajab, P. and Khan, A.R. (2006). Determining the adulteration of natural milk with synthetic milk using AC conductance measurement. Journal of Food Engineering, 77(9): 472-411.
● Shweizer, S., Vaihinger, W. and Gupel, F. (1994). Characterization of Food Freshness with Sensor Arrays. 2nd Edition, pp. 87-90.
● Zhung, W. and Zhou, W .(1997) Determination of protein content of whey powder using electrical conductivity measurement. International Dairy Journal, 7(10): 647-653.
