Good and Bad classification of Brassica oleracea

Brassica oleracea, commonly known as kohlrabi, is a nutritious cruciferous vegetable widely consumed in South Asia. It is valued for its low calorie content, high moisture level, and crisp texture, making it suitable for healthy and diabetic-friendly diets. Kohlrabi is a good source of dietary fiber, vitamin C, vitamin B6, and minerals such as potassium, calcium, and magnesium, which support digestion, immunity, bone health, and cardiovascular function.
The standard shelf life of Brassica oleracea (kohlrabi) depends mainly on storage conditions. At ambient (room) temperature (25–30 °C), kohlrabi typically remains acceptable for 2–3 days. Rapid moisture loss, surface wrinkling, textural hardening, and microbial spoilage occur due to its high respiration rate and exposure to uncontrolled environmental conditions.
Fresh kohlrabi samples exhibiting light green to pale green coloration with smooth, firm, and intact skin represent better-preserved quality. Slight surface dullness and minor shrivelling indicate early moisture loss and onset of senescence. In contrast, severely deteriorated samples show yellowing or browning, surface cracks, fungal growth (white or grey mycelium), tissue softening, and decay, which are typical symptoms of microbial spoilage and advanced senescence. These changes reflect enzymatic tissue degradation, increased respiration rate, and microbial invasion during prolonged storage. The observations clearly indicate that after extended storage under uncontrolled or suboptimal conditions, kohlrabi becomes unsuitable for consumption, confirming its limited shelf life.
Sample Collection
Fresh and mature Brassica oleracea (kohlrabi) samples were collected from local markets of Malda Town, West Bengal, India (24°59′N, 88°08′E), and the collection location was mapped using GPS coordinates. Immediately after procurement, the samples were sorted to remove damaged, bruised, or visibly spoiled vegetables. Selected samples were thoroughly washed with normal tap water to remove adhering soil and surface contaminants.
Digital images of the samples were captured using a smartphone (Vivo T2x) operating on Android version 12. The device was equipped with an MTK Dimensity processor, 6 GB RAM, and 128 GB internal storage. Image acquisition was carried out under uniform lighting conditions to ensure clarity and consistency.
Approximately 1000 images were captured for dataset development. The images were analyzed to observe variations in color, surface texture, firmness, and visible spoilage characteristics.
In this dataset, the bad image folder contains 500 images of Brassica oleracea (kohlrabi), and the good image folder also contains 500 images of Brassica oleracea (kohlrabi). Therefore, the total number of images in the dataset is 1000.