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This study demonstrates a method to quantitatively measure the oleophobicities of food packaging paper via using a tracer‐assisted headspace gas chromatography by adding a 40‐μL droplet of toluene‐doped oil onto a sample surface, wherein toluene behaves as volatile tracer. After 20 s, the sample was turned vertically to remove the oil and placed in a headspace vial. The amount of toluene in the residual oil adhered to the sample surface was quantified using headspace gas chromatography under full‐evaporation conditions. The results exhibit satisfactory precision (RSDs < 2.5%) and provide quantitative information on oleophobicity. The proposed method is simple, efficient and suitable for batch sample testing. [ABSTRACT FROM AUTHOR]

• Determination of starch gelatinization temperatures by a headspace GC technique. • Measuring the tracer release from liquid during an automated temperature ramping. • The present method is simple, accurate and suitable for the batch sample testing. This paper reports on an automated temperature-programmed headspace GC technique for the determination of gelatinization temperature of starch. 1-butanol was used as a tracer and added to the starch-solution for the test. Based on measuring the GC signal of 1-butanol in the headspace with the temperature increasing, two transition points (corresponding to the onset temperature and the ending temperature of starch gelatinization) were observed by plotting the GC signal of 1-butanol vs. the temperature. The results showed that the method has a good measurement precision (the standard deviation < 1 °C) and accuracy (the average relative differences = 3.9%, compared to a standard reference method). The present method is simple and suitable for the gelatinization temperature testing for starch samples. [ABSTRACT FROM AUTHOR]

The present work reports on the development of a pressure-affected based headspace (HS) analytical technique for the determination of calcium carbonate content in paper samples. By the acidification, the carbonate in the sample was converted to CO 2 and released into the headspace of a closed vial and then measured by gas chromatography (GC). When the amount of carbonate in the sample is significant, the pressure created by the CO 2 affects the accuracy of the method. However, the pressure also causes a change in the O 2 signal in the HS-GC measurement, which is a change that can be used as an indirect measure of the carbonate in the sample. The results show that the present method has a good precision (the relative standard deviation < 2.32%), and good accuracy (the relative differences compared to a reference method was < 5.76%). Coupled with the fact that the method is simple, rapid, and accurate, it is suitable for a variety of applications that call for the analysis of high carbonate content in paper samples. [ABSTRACT FROM AUTHOR]

• Simultaneous determination of amphiphobicities of material surface by a dual-indicator headspace gas chromatographic technique. • Based on measuring the GC signal of two volatile indicators remaining on the sample placed in headspace vial. • The present method is simple and practical, and suitable to be used in the batch sample testing. This paper reports on a new method for simultaneously determining the amphiphobicities of material surface by a dual-indicator assisted headspace gas chromatography. After adding 40 μL of both methanol-water and toluene-oil droplets on the sample surface for 20 s, the sample was turned vertically (to remove water and oil) and then placed in a headspace vial. The amount of methanol and toluene in the residual water and oil adhered to material surface was quantified using headspace gas chromatography. The results showed that the method has good measurement precision (RSD < 4.58%). It can be an effective tool for simultaneously determining the amphiphobicities of material surface. [ABSTRACT FROM AUTHOR]