SUITABLE LEVEL AND LONGEBILITY OF CARROT MILK

Abstract

Carrot milk was prepared by using different level of carrot juice to evaluate the quality and the shelf life of carrot milk at room and freezing condition. Firstly, different levels of Carrot milk were manufactured and their qualities were measured with the help of some physical (Smell, Color, Taste), Chemical (Acidity, pH, Protein, Fat, TS, SNF) and microbiological tests (Standard plate count test and Coliform test). Panel test was conducted to select the suitable level of carrot juice. In the first panel test, carrot juice was used in different concentration to make carrot milk such as, control, 5%, 10%, 15% and 20% and two samples those contain 10% and 15% carrot juice respectively were selected. From the second panel test, 15% carrot juice and 5% sugar was selected for third panel test. In third panel test the selected carrot milk was divided into four samples by using different amount of cardamom (elachi) and cinnamon (darchini). After the third panel test, 15% carrot juice, milk, sugar and cardamom was selected finally. Chemical analysis showed that addition of carrot juice declined the percentage of fat (3.48%) in carrot milk but increased the acidity (0.21%), specific gravity (1.046), pH (7.2), SNF (12.31%), TS (15.34%) and protein (3.48%). Lower percentage of TS, SNF were observed in carrot juice than milk. So, the addition of carrot juice decreased the TS (2.52%), SNF (2.32%) content of carrot milk (carrot juice and milk). Carrot milk also showed higher amount of TS (15.34%) and SNF (12.31%) due to addition of sugar and cardamom with carrot juice and milk. Acidity level and pH value were higher in the carrot milk. Both types of carrot (Raw and Boiled) contained higher amount of total phenolics than milk. Boiled carrot contain highest amount of total phenolics. Microbiological tests were conducted to observe the microbial count and longevity of milk, carrot juice, carrot milk and carrot milk with sugar and cardamom. Carrot milk contained lower amount of bacteria than other samples. The fewer amounts of bacteria in carrot milk due to the antibacterial activity of carrot juice. Carrot milk and carrot milk with sugar and cardamom change their color after 6.5 hrs in Methylene Blue Reduction Test. So the samples were good. As it was found carrot juice contained higher amount of total phenolics. Phenolic compounds have some source of antibacterial property. Sugar and Cardamom containing carrot milk had lower amount of bacterial population than plain milk due to presence of carrot juice which has antimicrobial activity. The presence of coliforms in carrot milk and carrot milk with sugar and cardamom samples was lower than plain milk sample. The standard plate count test was also conducted on the freeze samples to find the bacterial population and the stability of carrot milk in freezing condition (-5°C). Bacterial population was lower in each sample due to preserve in freezing condition. Plain milk always showed higher amount of bacteria than carrot milk and carrot milk with sugar and cardamom. On the basis of this experiment, it can be suggested that carrot milk with sugar and cardamom can be preserved in freezing condition and it can be easily marketed commercially for the consumers.