Evaluation of the effects of canning variables on the mineral composition of canned cowpeas (Vigna unguiculata l. Walp) using multi-response analysis.

This study investigates the effects of canning variables—cooking time, storage time, vinegar volume, salt, and sugar—on the mineral composition of canned cowpea (Vigna unguiculata (L.) Walp) to identify conditions that optimize mineral retention. Using a two-level fractional factorial design and multi-response desirability functions, the research found that longer storage time (360 days at 30 ± 5 °C), higher vinegar (30 ml), and salt content (9.0 g), combined with shorter cooking time (18–36 minutes), enhance retention of essential minerals such as calcium, copper, iron, manganese, magnesium, phosphorus, and zinc. Sugar content showed no significant effect on mineral preservation within the tested range. The findings suggest that optimized canning conditions can preserve mineral content effectively, supporting the nutritional value of canned cowpeas and contributing to food security and valorization of local agricultural practices.