Fruit content of fruit juice and apple juice content of cider using DNA methodology - Dissertation Example

The people want the analytical techniques to be very quick and easy for the identification of the honesty and accuracy of the ingredients. Many modern analytical techniques are used for the analysis of the plant or animal species in the foods. The techniques based on DNA are much common nowadays. The people have lost their hope on chemical analysis as they cannot predict the correct results because of the varying processing methods. DNA is resistant to the food processing method hence this can used for the analysis.

Most of the molecular genetic techniques are based on the PCR, pyrosequencing and CAPS (Cleavable Amplifiable polymorphic Sites). Aim of the project: To determine the fruit content of the fruit juice, using the DNA methodologies. Main work packages: The fruit juices are selected and tested for the fruit content based on the value of the juice and to check the level of fraudulent substitution of other fruits in the juice using the DNA methodologies. The high value fruit juices are accidentally or fraudulently substituted with the other fruits.

This affects the trustworthy of the product in the customers mind. Hence a novel technique that can identify these fraudulent are required for the prevention. (Bauer et al. 2003). Outline of the project: The fruit juices were obtained from the commercial juice producers. The fresh juices were mixed thoroughly by shaking and inverting. (Doyle and Doyle 1987). The fruit juices are then diluted with the ultra pure water. This dilution is done to reduce the percentage of sugar in the juice. The DNA was extracted from the fruit juices using the Standard CTAB DNA extraction method.

(Kress et al. 2005). One ml of the sample was suspended in the 5 ml of the CTAB buffer, 100mmTris HCl, 20mM EDTA, 1.4M NaCl and 40µl of proteinase K solution. It was vigorously shaked ad stored at 60 degree Celsius overnight. (Doyle and Doyle 1987). The clear supernatant was removed and added with equal volume of chloroform and centrifuged and the supernatant was collected. Equal volume of isopropanol was added to precipitate DNA. The pelleted DNA was washed with ethanol and dried and stored in the 1X TE buffer.

The concentration of the DNA was estimated using suitable methods. The DNA obtained was amplified before moving to the PCR. The amplified product was confirmed with the gel electrophoresis. The design of the primer is an important part of PCR. The primers for the psbA-trnH chloroplast are used for the Taberlet PCR. (Delano and Schmidt 2004). The products can be amplified using the Taberlet PCR and used for further studies. The PCR products were then run in the gel electrophoresis. The DNA fragments were separated in the gel electrophoresis and the gel images are captured in the Gel Doc.

The DNA are then separated and extracted from the gel and the restriction enzymes are used for the further analysis. The restriction enzymes are specific for the species. The restriction enzymes that can be used for fruit juice analysis are Acil, Apol, Dbel, Mbol,Mnll, NlaIII, TaqAl etc., (Taberlet et al. 1991). The Full length of the DNA can be found by aligning the contigs of the sample. Consensus sequences are generated using the Bioinformatics tools. These consensus sequences can then be used for the analysis of PCR-RFLP patterns.

The Apol and Dbel are used for the analysis of the six different fruit species such as apple, blueberry, elderberry, grape, pear and pomegranate. If Apol