In the world of tea production, precision and quality control are paramount, and a groundbreaking study led by Dr. Hu Yan from Zhejiang University is set to revolutionize the way we monitor and grade Fu brick tea during its critical fungal fermentation stage. The research, published in the journal *智慧农业* (translated as *Smart Agriculture*), introduces a novel approach that combines hyperspectral imaging technology with advanced deep learning techniques, offering a rapid, non-destructive method for assessing tea quality.
Fu brick tea, a popular fermented black tea, undergoes a “Jin hua” fermentation process that significantly influences its quality, flavor, and functional properties. Traditionally, monitoring this process has been challenging, often relying on time-consuming and destructive methods. However, the team led by Dr. Hu has developed a cutting-edge solution that promises to streamline quality control and enhance processing efficiency.
The study leverages visible-near-infrared (VIS-NIR) and near-infrared (NIR) hyperspectral imaging to capture detailed spectral data of Fu brick tea during fermentation. By analyzing key quality indicators such as moisture, free amino acids, tea polyphenols, and tea pigments, the researchers were able to track the tea’s evolution throughout the fermentation process.
One of the standout innovations in this research is the development of the Spectra-SE-CNN model, which integrates the squeeze-and-excitation (SE) attention mechanism into a convolutional neural network (CNN). This model significantly outperformed traditional CNN models, demonstrating enhanced feature extraction and improved classification accuracy. “The SE attention mechanism allows the model to adaptively recalibrate channel-wise feature responses, focusing on the most informative spectral bands and suppressing irrelevant signals,” explained Dr. Hu. “This results in a more robust and accurate model for identifying the fermentation stages.”
The Spectra-SE-CNN model achieved impressive results, with high correlation and modeling stability for key quality indicators. For instance, the model demonstrated a strong predictive capability for moisture, tea pigments, and tea polyphenols, with R2p values of 0.8595, 0.8525, and 0.8383, respectively. However, the detection of free amino acids proved more challenging, with a lower R2p value of 0.6702, likely due to their minor changes during fermentation or weak spectral response.
To enhance the interpretability of the model, the researchers employed the Grad-CAM technique, which generates heatmaps to visualize the key regions the model focuses on. This not only improved the model’s transparency but also provided valuable insights into the specific features that are most influential in identifying fermentation stages.
The implications of this research extend beyond the tea industry. The integration of hyperspectral imaging technology with intelligent algorithms offers a pathway for broader applications in intelligent agricultural product monitoring, quality control, and automation of traditional fermentation processes. “This approach has the potential to transform the way we monitor and control quality in various agricultural products,” said Dr. Hu. “By enabling rapid, non-destructive, and high-resolution assessment, we can enhance efficiency and consistency in production.”
The study’s findings were published in *智慧农业*, a leading journal in the field of smart agriculture. This research not only highlights the potential of deep learning in hyperspectral spectral feature extraction but also paves the way for future developments in intelligent agricultural monitoring and quality control. As the agricultural industry continues to embrace technological advancements, the integration of hyperspectral imaging and deep learning is poised to play a pivotal role in shaping the future of food and beverage production.

