基于深紫外LED吸收光谱的嵌入式酱香型白酒鉴别仪研究

A study of an embedded discriminator for maotai-flavour liquor using ultra-violet LED absorption spectroscopy

在高仿白酒不断充斥市场的环境下,真假白酒的鉴别已经成为人们食品安全重点关注的问题之一.基于不同酱香型白酒中糠醛成分在276 nm波长处的紫外光吸收光谱,提出一种低成本、便携式的酱香型白酒紫外吸收光谱鉴别仪.以波长为276 nm的低成本紫外LED作为激发光源,该光源入射装有待测白酒样品的比色皿中后,其透射光由高灵敏的韩国GUVB-S11SD紫外光电传感器转换为电信号,经放大滤波后进入16位ADC芯片进行模数转换,转换后的数字信号进入高性能32位ARM单片机中进行运算.采用稀释法配置不同质量浓度的糠醛溶液对设计的鉴别仪进行了传感校准实验,考虑到吸光度的非线性效应,采用分段拟合法进行了拟合,其相关系数分别为0.99656和0.98555.制备习酒和酣客两种酱香型白酒的酒样,进行了鉴别仪的验证实验.实验结果表明,鉴别仪在60~300 mg/L范围内,其线性度为0.99656,可以实现对不同酱香型白酒进行实际鉴别,并且成本低、体积小、操作方便,在酱香型白酒真伪鉴别中具有一定的应用前景.

The identification for fake liquor has become one of the key issues for food safety under the condition of high imitation liquor flooding the market.Based on the ultra-violet absorption spectra at 276 nm for furfural molecule in different Maotai-flavor liquors,a low-cost and portable identification instrument was proposed.First of all,a low-cost ultra-violet LED with a center wavelength of 276nm was used as the excitation light source.After the light source injected into a cuvette equipped with a liquor sample,its transmitted light is converted into an electrical signal by a highly sensitive ultra-violet photoelectric sensor(Korean GUVB-S11SD).Then,the amplified and filtered signal was acquired by the ADC chip to analog-to-digital conversion,and finally was processed in a high-performance 32-bit ARM microcontroller.Secondly,the calibration experiment was performed via the solution dilution method with different mass concentration gradients.The piecewise fitting method was adopted to compensate for the nonlinear effect of absorbance with the correlation coefficients of 0.99656 and 0.98555,respectively.Finally,the sample of Xijiu and Hankol Maotai liquor were prepared to verification of the discriminator.The experimental results show that the discriminator can realize the actual identification of various maotai-flavor liquors with the range of 60~300 mg/L and the linearity of 0.99656.Therefore,the discriminator,which manifests low cost,compact size and convenient operation,has a certain potential prospect in the identification application of maotai-flavor liquors.