Abstract:
There are challenges in the utilization of soybean-based foods due to undesirable flavors
associated to the Lipoxygenase and trypsin inhibitors causing oxidation of
polyunsaturated fatty acids (Linoleic Acid and alpha linolenic) in soybean. This study
aimed to prepare soybean based yoghurt with different amounts of lemon grass
essential oil in the ratios of 0, 25, 50, 75, and 100 μl per litter of soy yoghurt. The
different treatments of Soybeans based yoghurt were analyzed for protein by Kjedhal
method, fats by Soxhlet method, total ash by muffle furnace method, crude fiber, pH,
titratable acidity, syneresis and viscosity by AOAC method, total phenolic compounds
2
by spectrophotometric method and sensory analysis by effectivetests with 10 panelists
using 5 hedonic scale tools. The results ranges for Moisture content,%(89.389.6%);Protein,%(5.5-6.8%);
Fat,%(2.7-3.6% ); Total Ash%(0.43-0.53 %); Crude
Fiber,%(0.06-0.33 %) and Carbohydrate,%(0.59-0.93 %). Physiochemical properties
ranges for PH (4.30-5.59 ); Viscosity,Pa.s(2.85- 3.17 ); Titrable acidity, g\l (0.01-0.07
)and Synersis (6.44-7.56 ) and Total Phenolic compound mg/g(8.59-18.40). The level
of pH showed a significant variations between the treatments while titratable acidity,
syneresis and viscosity did not show any significant variations. Total phenolic
compounds varied between8.59 to 18.40 mg/g and Sensory evaluation showed that
the treatment (100 μl) with highest level of lemon grass essential oil per liter of soy
yoghurt was the most liked. In conclusion, incorporation of lemon grass essential
improved the level of phenolic compounds and sensory properties of yoghurt. More
studies that are extensive need to be carried out on the microbial status and other
parameters of the lemon grass extract enriched soy yogurt.
