Peanut skins-fortified peanut butters: Effects on consumer acceptability and quality characteristics

- Peanut skins are a viable high phenolics functional ingredient in peanut butter.
- Peanut skin heat treatment and levels of use impact resultant peanut butter quality.
- Consumers find peanut skin fortified peanut butter acceptable.
- Acceptable peanut skin fortified peanut butters meet US FDA standard of identity.
- Acceptable high phenolics peanut butters will allow product line diversification.

Peanut skins (PS), high phenolics by-products from peanut processing, are potential functional ingredients. Effects of fortification with ground PS (3 types: dry-blanched, light- and medium-roasted) on peanut butter (PB) quality characteristics and consumer acceptability were evaluated. PS were added in concentrations of 0 (control), 2.5 and 5.0 g PS/100 g PB. Data were analyzed with Mixed Model ANOVA. Significant effects (P < 0.05) on product appearance and physical characteristics depended on level of incorporation and type of skins used; the greatest impact on objective appearance (L*, a*, b* color and particulate presence) and instrumental physical properties (spreadability and texture profile analysis parameters) occurred with incorporation of 5.0 g medium roasted PS/100 g PB. Consumer sensory panelists (P < 0.05) noted an increase in stiffness with incorporation of roasted PS at both levels, and less acceptable spreadability with incorporation of 5.0 g light or medium-roasted PS/100 g PB when compared to the control. Panelists also found PS addition affected acceptability of appearance more than flavor, texture or overall acceptability. With incorporation of 2.5 g PS/100 g PB, PS addition produced PBs that equaled the control in overall acceptability, regardless of heat treatment. At the 5.0 g PS/100 g PB incorporation level, PBs containing medium-roasted PS were less acceptable (P < 0.05) than all other formulations.