Qualitative and quantitative method for extracting and analyzing aroma substances of scented rice

Abstract

The invention relates to a qualitative and quantitative method for extracting and analyzing aroma substances of scented rice. The method comprises the following steps: crushing air-dried scented rice grains, sieving, sampling, extracting in an extraction kettle having a temperature of 30-54DEG C and a pressure of 12-32MPa under a CO2 flow velocity of 16L/h for 120min; taking aroma substances at all extraction temperatures under all pressures, and measuring to obtain the absolute contents of total aroma substances of the scented rice grains at different extraction temperatures under different pressures; and carrying out qualitative analysis of the aroma substances through GC-MS, and confirming the concrete names and molecular formulas of the aroma substance components and respective contents of all the aroma substances through an alternative moving window factor analysis process and content analysis. Scented rice aroma is extracted through a supercritical CO2 process, qualitative analysis is carried out through the GC-MS, and the alternative moving window factor analysis method and content analysis are adopted to confirm the concrete names and molecular formulas of the aroma substance components and respective contents of all the aroma substances, so the method has the characteristics of rapidness, simplicity, no organic solvent pollution, no chemical residual, and high extraction efficiency.

Description

technical field [0001] The invention belongs to the technical field of extracting and analyzing aroma substances of fragrant rice, in particular to a qualitative and quantitative method for extracting and analyzing aroma substances of fragrant rice. Background technique [0002] At present, steam distillation is mainly used for the extraction of aroma substances in fragrant rice, which has low yield, high cost and long time consumption. [0003] So far, the identification methods of aromatic rice aroma mainly include chewing method, hot water method, potassium hydroxide soaking method, cooking method and capillary gas chromatography-mass spectrometry in instrumental methods, headspace gas chromatography-mass spectrometry, and Headspace dynamic detection system (including headspace sampling, Tenax trap, GC-MS, GC-O and multivariate analysis); in recent years, a variety of instruments for rapid aroma determination have been developed, such as "aroma meter", "test taste instru...

AI Technical Summary

Problems solved by technology

However, 2-AP substance is an aroma component that is easy to escape when the temperature is higher than 40°C during the cooking process, and the volatile oil components released during the cooking process of fragrant rice such as alcohols, aldehydes, ketones, shikimic acid derivatives, Nitrogen-containing aroma substances have also been studied and reported many times, so the comparison of the aroma quality of many aromatic rice varieties is not comprehensive based on the difference in the content of 2-AP substances.

The aroma of fragrant rice is composed of alcohols, aldehydes, ketones, shikimic acid derivatives, and nitrogen-containing aroma substances (Mahatheeranont et al, 2001; Yang et al, 2008). Gas chromatography-olfactory discrimination method ( GC-O) and gas chromatography-liquid chromatography (GC-MS) have been used to identify more than 60 kinds of volatile oil components in aromatic rice that distinguish them from non-aromatic rice (Maraval et al, 2008). The overlapping of isomer peaks is difficult to distinguish accurately by mass spectrometer. In order to solve this problem, Professor Liang Yizeng et al. used the qualitative and quantitative analysis method of GC-MS Alternate Moving Window Factor Analysis (AMWFA) to analyze the volatile substances of traditional Chinese medicine.