MicroVi: A Cost-Effective Microscopy Solution for Yeast Cell Detection and Count in Wine Value Chain.

Area of Science:

• Oenology and Viticulture
• Microbiology
• Optical Engineering

Background:

• The wine industry seeks methods to enhance wine quality throughout production.
• Accurate microbial assessment is crucial for wine quality control.

Purpose of the Study:

• To introduce MicroVi, a novel, cost-effective, chip-sized microscopy solution for detecting and counting yeast cells in wine.
• To demonstrate MicroVi's capability to perform microbial analysis comparable to traditional optical microscopy but with a smaller footprint and automated features.

Main Methods:

• Utilized computer vision pipelines, including SIFT feature extraction, image composition for enhanced resolution and scanning, holographic reconstruction, and Hough transform for particle counting.
• Achieved a resolution of 2.19 µm, validated using the USAF Resolving Power Test Target 1951.
• Calibrated cell counts for *Saccharomyces cerevisiae* against a standard optical setup, achieving linear results from 0.5 to 50 million cells/mL.

Main Results:

• MicroVi demonstrated comparable performance to traditional optical microscopy for sample measurement.
• The system achieved a resolution of 2.19 µm, capable of resolving fine details.
• Linear calibration was established for *Saccharomyces cerevisiae* cell counts across a significant concentration range.
• Qualitative resolution of other microorganisms, including *Brettanomyces bruxellensis* and *Lactobacillus plantarum*, confirmed system reliability.

Conclusions:

• MicroVi offers a reliable, automated, and cost-effective solution for microbial assessment in the wine industry.
• The chip-sized microscope provides high resolution and accurate cell counting, supporting wine quality improvement.
• The technology's versatility extends to identifying various yeast and bacterial species, enhancing its utility in enology.