Debittering Moringa oleifera (Lam.) Leaves in Fortified South Indian Instant Soup

Moringa oleifera (Lam.) is a nutritious plant species that has the potential to alleviate food insecurity in low- and middle-income regions. However, the bitter taste associated with M. oleifera leaves is a key barrier to its acceptance as food. It was hypothesized that reducing the bitterness in M. oleifera-fortified instant soups would increase their acceptance.

Acid soaking and the addition of a sweetener (aspartame) were examined for their effectiveness in the removal of bitter taste in M. oleifera leaves. Fifty assessors rated the acceptance and perceived bitterness in a randomized complete block sensory evaluation. South Indian instant soup samples with 0%, 50% and 100% replacement of vegetable powder with M. oleifera leaf powder were evaluated.

Acceptance for M. oleifera-fortified instant soups was higher for samples with lower perceived bitterness. Addition of sweetener was found to be effective in increasing the acceptability and reducing the perceived bitterness at the 50% replacement level, but not at the 100% replacement level. Perceived bitterness did not decrease in formulations with acid-soaked M. oleifera leaves.

Undesirable organoleptic properties need to be masked or removed for the acceptance of M. oleifera leaves as a regular food. We recommend that foods fortified with M. oleifera to include a sweet excipient to reduce the bitter tastes.

Fortified instant soup samples with reduced perceived bitterness had increased acceptability. Debittered M. oleifera-fortified foods would appeal to consumers, which would increase their consumption and could lead to reduced prevalence of micronutrient deficiencies.