Authors: Gade Raj Baburao, Professor Abhishek Popat Bangar, Professor Bhosale S. B., Dr. A. A. Khatri
Abstract: Onions lose 30–40% of their weight and quality in storage, and up to 70–80% in poor structures, because bulbs keep respiring while heat and moisture build up around them. Controlling how a store exchanges air with its bulbs, termed here breathing-controlled storage, is widely proposed as a low-cost remedy for small farms. This paper presents a focused narrative review that synthesises five studies: a six-month field trial of an improved fan-aerated NHRDF store in Maharashtra, a four-week trial of a fan-aerated bin in Bangladesh, a broad review of postharvest treatment, storage and quality evaluation, an IoT design with UV-C disinfection, and a humidity-controlled window design. The review examines three connected themes: the physiology that sets the loss window, the strength of the empirical evidence, and the conditions that matter for deployment. In the field trial, total loss was 14.52% in the aerated store against 33.40% in a conventional ventilated store and 38.45% in a farmer's store. The bench trial reported a peak of 97.5% marketable bulbs against 91.6% outside the bin, although room air was almost identical in both places. Neither automation design reports data from stored onions. The trials are short or single-site, and none measures airflow or bulb respiration directly. The review contributes a comparative table, a conceptual architecture for a sensor-aided aerated store, and a prioritised agenda of research gaps.
