Manhal Mohammed Dafaalla Osman
Department of Food Science and Technology, Faculty of Agriculture, Al-Zaeim Al-Azhari University, P.O. Box 1432, Khartoum North 13311, Sudan
Kamal Awad Abdel Razig
Department of Food Science and Technology, Faculty of Agriculture, Al-Zaeim Al-Azhari University, P.O. Box 1432, Khartoum North 13311, Sudan
ABSTRACT
The utilization of soybean milk in manufacturing yoghurt in Sudan was investigated. Soybean milk was prepared from grinded soybean seeds. Four samples of soy yoghurt product were used, namely sample A) 100% soymilk (sample B) 1:1 soymilk: cow milk), sample C (2:1 soymilk: cow milk) and sample D (1:2 soymilk: cow milk). The prepared soy yoghurt samples were stored at refrigerator temperature (10±2oC) followed by analyses at 0, 5, 10, 15 and 20 days intervals. The chemical compositions of soybean milk used were the total solids (13.15%), protein (7.64%), fat (2.75%), pH-value (6.70) and titratable acidity (0.20%).The type of milk significantly (p<0.05) affected the pH-value of the soy yoghurt. Sample A was the highest (4.50), sample D the lowest (3.30) while sample B and sample C were at an intermediate position (3.50 and 3.70 respectively). Storage period significantly (p<0.05) affected the pH-value of soy yoghurt, the highest value (4.30) was obtained at the beginning of the storage period, while the lowest value (3.00) at the end. The type of milk significantly (p<0.05) affected the titratable acidity of the soy yoghurt. Sample A was the lowest (1.12%), Sample D was the highest (2.50%), while samples B and C were in an intermediate position. Storage period significantly (p<0.05) affected the titratable acidity of soy yoghurt. The lowest titratable acidity (1.21%) was obtained at the beginning of storage period and the highest (2.60%) at the end. The type of milk significantly (p<0.05) affected the wheying off of the soy yoghurt. Sample A was the highest (2.70 ml), sample D was the lowest (1.70 ml), while samples B and C were at an intermediate position. Storage period significantly (p<0.05) affected the wheying off of soy yoghurt. The lowest wheying off (0.00 ml) was obtained at the beginning of storage period and the highest (4.00 ml) at the end. The chemical analyses of soy yoghurt samples at zero time processing, sample A) 100% soymilk (was the highest (31.20%) for total solids and protein content (16.70%),while sample D (1:2 soymilk: cow milk) was the lowest (15.70%) for total solids and protein content) 11.25). Sample B and C were at an intermediate position. Sample A was the lowest (2.20%) for fat content, sample D was the highest (3.25%),while samples Band C occupy an intermediate position. The sensory evaluation significantly (p<0.05) affected by The type of milk and storage period revealed that, the best score (p<0.05) in appearance (4.38), flavour (4.10), texture (4.22) and overall acceptability (4.28) in sample D(1:2 soymilk: cow milk), the worst was recorded by sample A (Soymilk 100%) for appearance (2.68), flavour (3.48), texture (3.36) and overall acceptability (3.44). The other samples were at an intermediate position. It was found that 10 days storage period at refrigerator temperature (10±2oC) was quite satisfactory to attain good quality soy yoghurt.
PDF References
How to cite this article
Manhal Mohammed Dafaalla Osman and Kamal Awad Abdel Razig, 2010. Quality Attributes of Soy-yoghurt During Storage Period. Pakistan Journal of Nutrition, 9: 1088-1093.
DOI: 10.3923/pjn.2010.1088.1093
URL: https://scialert.net/abstract/?doi=pjn.2010.1088.1093
DOI: 10.3923/pjn.2010.1088.1093
URL: https://scialert.net/abstract/?doi=pjn.2010.1088.1093
REFERENCES
- Buono, M.A., L.E. Erickson and D.Y.C. Fung, 1990. Carbohydrate utilization and growth kinetics in the production of yoghurt from soymilk. Part II: Experimental and parameter estimation results. J. Food Proc. Preserv., 14: 179-204.
CrossRef - Buono, M.A., L.E. Erickson, D.Y. Fung and I. Jeon, 1990. Carbohydrate utilization and growth kinetics in the production of yoghurt from soymilk. Part I: Experimental methods. J. Food. Proc. Preserv., 14: 135-153.
CrossRef - Chang, I.C., H.F. Shang, T.F. Lin, T.H. Wang, H.S. Lin and S.H. Lin, 2005. Effect of fermented soymilk on the intestinal bacteria ecosystem. World J. Gastroenterol., 11: 1225-1227.
Direct Link - Friedman, M. and D.L. Brandon, 2001. Nutritional and health benefits of soy proteins. J. Agric. Food Chem., 49: 1069-1086.
CrossRefPubMedDirect Link - Lee, S.Y., V.C. Morr and A. Seo, 1990. Comparison of milk based and soy milk yoghurt. J. Food Sci., 55: 532-536.
CrossRefDirect Link - Lucey, J.A., M. Tamehana, H. Singh and P.A. Munro, 2000. Rheological properties of milk gels formed by a combination of rennet and glucono-lactone. J. Dairy Res., 67: 415-427.
PubMedDirect Link - Mital, B.K., R.S. Schallenberger and K.H. Steinkraus, 1973. Alpha-galactosidase activity of lactobacilli. Applied Microbiol., 26: 783-788.
Direct Link - Pinthong, R., R. Macrae and J. Rothwell, 1980. The development of a soya-based yoghurt. II. Sensory evaluation and analysis of volatiles. J. Food Technol., 15: 653-659.
CrossRefDirect Link - Sugimoto, H. and J.P. van Buren, 1970. Removal of oligosaccharides from soy milk by an enzyme from Aspergillus saitoi. J. Food Sci., 35: 655-660.
CrossRefDirect Link - Tamime, A.Y. and R.K. Robinson, 1999. Yoghurt: Science and Technology. 2nd Edn., Woodhead Publishing Ltd., London, UK., ISBN-13: 9781855733992, Pages: 619.
Direct Link - Tuitemwong, P., L.E. Erickson, D.Y. Fung, C.S. Setser and S.K. Perng, 1993. Sensory analysis of soy yoghurt and frozen soy yoghurt produced from rapid hydration hydrothermal cooked soy milk. J. Food Qual., 16: 223-239.
CrossRefDirect Link