The Effect of Boiling on the Nutritional Quality and Sensory Characteristics of Cowpeas

Abstract

Aim: This study aimed at determining the effect of boiling on the nutritional quality and sensory characteristics of cowpeas (Vigna unguiculata).

Methods: One kg of fresh cowpea pods was procured from a local market and sorted for uniform size and color, then soaked. The soaked cowpeas were divided into two halves: one half was boiled for 30 minutes, while the other half was left uncooked as a control group. The boiled cowpeas were drained and cooled to room temperature. The sensory characteristics of the cowpea seeds were evaluated using a 9-point hedonic scale. The sensory attributes evaluated included color, flavor, texture, and overall acceptability. The sensory analysis was conducted by a panel of trained sensory evaluators.

Results: The study found that the fat content remains relatively consistent between boiled and uncooked cowpeas. It was also found that the fiber content of cowpeas remains relatively stable even after boiling. The study further showed that boiling cowpeas led to a reduction in phytic acid content. The results also showed that the boiling process had a detrimental effect on the vitamin C content of cowpeas. The results further showed a significant increase in protein content of boiled cowpeas compared to uncooked cowpeas. The results also showed a significant increase in the iron content of boiled compared to uncooked cowpea. The zinc content was also significantly higher in boiled cowpeas compared to uncooked cowpeas. However, the calcium content was found to be significantly lower in boiled cowpeas. The sensory analysis showed that flavor of boiled cowpea seeds was more pronounced and developed compared to unboiled seeds.

Conclusion: The study conclude that boiling enhances the nutritional value of cowpeas by increasing their protein and mineral content but it causes a reduction in heat-sensitive vitamins, such as vitamin C.

Recommendations: This study recommend inclusion of boiling as a processing method for cowpeas to improve their nutritional value. The boiling time and temperature should be carefully controlled to avoid excessive loss of nutrients and ensure optimum nutrient retention. Based on this study, a boiling time of 60 minutes at 100°C is recommended for cowpeas.