The following literature may be useul for your research

Abstract: he purpose of the present study was to explore the utility of Jatropha (Jatropha curcas) seed oil for biodiesel production. The preliminarily evaluated Jatropha oil was transmethylated under optimized set of reaction conditions: methanol/oil molar ratio (6:1), sodium methoxide catalyst concentration (1.00%), temperature (65°C) and mixing intensity (600 rpm) providing 94.00% yield

of Jatropha oil methyl esters (JOMEs)/biodiesel. The gas chromatographic (GC) analysis showed that JOMEs mainly comprised of six fatty acids: linoleic (49.75%), stearic (16.80%), oleic (13.00%), palmitic (12.15%), arachidic (5.01%) and gadoleic (2.00%) acids. 1H-NMR spectrum of JOMEs was also recorded. The thermal stability of the JOMEs produced was assessed by thermogravimetric analysis (TGA). The fuel properties of the biodiesel produced were found to be within the standards specifications of ASTM D 6751 and EN 14214.  

JATROPHA CURCAS SEED OIL AS A VIABLE SOURCE FOR BIODIESEL

UMER RASHID1,2, FAROOQ ANWAR, AMER JAMIL 

AND HAQ NAWAZ BHATTI; Pak. J. Bot., 42(1): 575-582, 2010. 

Without instruments, the simple method to monitor transesterification of oils/fats is to measure their acid value by titirimetry. After reducing acid value drastically, the sample will be subjected to GC-MS to quantify FAME.

The gas chromatographic (GC) analysis is applied to analyze oils, but for monitoring transesterification of oils/fats  acid value is measured by titirimetry. gas chromatography-mass spectrometry (GC-MS) is also used for identification and measurement of phospholipid peroxides at the 10 ng leve. Prepare pentafluorobenzyl esters of fatty acids and hydroxy fatty acids directly from phospholipids by transesterification at room temperature or from triglycerides at 60 degrees C. Oxidized lipids are extracted into dichloromethane and peroxide functions are reduced with sodium borohydride. Transesterification of phospholipids is carried out in dichloromethane with 20% (v/v) pentafluorobenzyl alcohol, 1% (w/v) potassium tert-butoxide and 0.2 N (m-trifluoromethyl phenyl) trimethyl ammonium hydroxide at room temperature for 30 min. Pentafluorobenzyl esters are purified on open silica columns, O-trimethyl silyl derivatives of the alcohol functions are formed, and GC-MS is carried out with negative ion chemical ionization detectionl. Animal and plant fats and oils are composed of triglycerides, which are esters containing three free fatty acids and the trihydric alcohol, glycerol. In the transesterification process, the alcohol is eprotonated with a base to make it a stronger nucleophile. Commonly, ethanol or methanol are used. As can be seen, the reaction has no other inputs than the triglyceride and the alcohol. Under normal conditions, this reaction will proceed either exceedingly slowly or not at all, so heat, as well as catalysts (acid and/or base) are used to speed the reaction. It is important to note that the acid or base are not consumed by the transesterification reaction, thus they are not reactants, but catalysts. Common catalysts for transesterification include sodium hydroxide, potassium hydroxide, and sodium methoxide.

This paper have information abouth GC caracterization of biodiese. Nohemí Gámez-Meza, Perla P. Alday-Lara, Harinder P. S. Makkar, Klaus Becker and Luis A. Medina-Juárez 2013. Chemical Characterization of Kernels, Kernel Meals and Oils from Jatropha cordata and Jatropha cardiophylla Seeds. Journal of the Science of Food and Agriculture, 93:1706-1710.

 Fatty acid methyl esters (FAME) were analyzed in a gas chromatograph (GC)  equipped with flame-ionization detector and fitted with a SP-2560 (100 m x 0.25 mm i.d. 25 m film thickness, Supelco, Bellefonte, PA) fused-silica capillary column. The carrier gas was nitrogen at a flow rate of 20 cm/s. The oven temperature was programmed: 140 (5 min), 140–170 (4°C/min), 170 (3 min), 170–200 (1.5°C/min), and 200°C (10 min). Injector and detector temperatures were held at 250°C. FAME peaks were identified by comparison with the retention time of the respective standards (Sigma Chemical Co., St. Louis, MO). 

thank you luis very much

I hope you have success in your research

I did as Luis suggested. Using GC with FID detector and SP coloumn. You may choose the right standard for it. It depends on your type of oil and alcohol you used. There are many types of FAME you can use. 

When you mix vegetable oil with methanol and catalyst, in principle the color changes to slightly green, it indicates that the reaction is in progress. Then just wait 40 minutes and let the mixture rest in the glycerin is separated spontaneously.

It is important to make sure that your feedstock contains very low water and free fatty acid for the transesterification reaction before starting the reaction. One could also follow the change in viscosity of the oil/biodiesel as the reaction progresses.

Transesterification of vegetable oils is nothing but removal of glyceryl moiety from oils. Basically 100% conversion of vegetable oil leads to the formation of 10 wt.% of glycerol. So one can easily monitor the reaction by quantifying the glycerol amount formed. Colour (mostly slight yellow) change during reaction (if glycerol removed from the oil) will give some idea about the reaction. 

If you use waste products to produce biodiesel, the glycerol byproduct shall have dark colour, while the methyl ester  will be clear. From the mass balance you can monitor the reaction. If initially there are water, gums and free fatty acids, soaps can be made at the interface and the yield is decreased, with consequent problems of separation.

To monitor the biodiesel production, is used metíico an excess of alcohol and a small amount of sodium hydroxide. The reaction temperature should be kept around 70 degrees Celsius and constant stirring .. When you mix all reagents, the solution becomes slightly green, mean reaction progress. Keep the temperature and time for 40 minutes. After it stopped shaking, the glycerin is separated, it is a good indication of the success of the reaction.

check the EU norms for the standard (EN 14105 for instance)

http://www.aidic.it/cet/13/32/137.pdf

https://www.canr.msu.edu/uploads/files/biodiesel_production.pdf

http://www.diva-portal.org/smash/get/diva2:443295/fulltext01.pdf

http://www.jocpr.com/articles/biodiesel-production-from-waste-cooking-oil.pdf

Article Production of biodiesel from vegetable oils

If you just want a simple method to follow up transesterification by GLC, a high temperature, non-polar column wound be a good solution. A short (5 - 10m) 0.32 mm ID capillary would have sufficient resolution for FAME, diglyceride and triglyceride (oil), but they may be eluted as multiple peaks for each class. Area under the peaks are the mass of each class of lipids and allow you to quantitate, if FID is the detector.

Programmed temperature from 280 -330 C would shorten the analysis time and good separation for each class of the lipids.

Optimization may help shortening your analysis time.

Also, sample preparation is important. The reaction product must must be acidified to stop the reaction, follows by washing to remove polar components, removal trace of water by anhydrous salt (sodium sulfate) and silylation to increase volatility of polar components or impurities.

Have a good luck.

the standards are included in EN 14214 specs, conversion must be at least 96,5%, glycerides are also specified. the simplest is to check viscosity, look for DeFilippis publication