Texture and flavor evaluation of peanut butter stabilized with natural waxes

Authors: Moser, Jill; Anderson, Julie; Hwang, Hong-Sik

Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/19/2022
Publication Date: 3/23/2022
Citation: Winkler-Moser, J.K., Anderson, J.A., Hwang, H. 2022. Texture and flavor evaluation of peanut butter stabilized with natural waxes. Journal of Food Science. 87(4):1851-1864. https://doi.org/10.1111/1750-3841.16118.
DOI: https://doi.org/10.1111/1750-3841.16118

Interpretive Summary: Peanut butter and other nut or seed butters are popular food products and can be a good source of protein and healthy oils that are naturally low in saturated fats and high in mono- or polyunsaturated fats. They are typically produced by grinding the nuts or seeds, producing a paste of ground particles and oil to which other ingredients such as salt, sugar, molasses and stabilizers may be added. Unless stabilizers are added, the oils will separate and rise to the surface of the product. Typical stabilizers used in peanut butter and other nut butters and spreads include fully hydrogenated oils or palm oil, which are high in unhealthy saturated fats. Therefore, more healthful alternative stabilizers are needed. Natural waxes, such as sunflower, rice bran, candelilla, or beeswax to stabilize peanut butter was previously evaluated and were found to prevent oil loss similar to commercial stabilizers. Therefore, in this study, the appearance, texture, and flavor of unsweetened peanut butter stabilized with 1 % to 2 % of these waxes were tested by a trained sensory panel. When rice bran wax, sunflower wax, and candelilla wax were used, the firmness and the force required to spread the peanut butter increased with increasing wax content, and the samples increased in dry appearance. On the other hand, beeswax stabilized samples remained less firm and were more oily in appearance. and the values did not change much with increasing wax content. The effects of wax-stabilizers on peanut butter flavor were less pronounced. There was a slight decrease in sweetness and increase in bitterness with increasing rice bran or candelilla wax, but this trend was not followed for beeswax. Samples stabilized with candelilla wax had slightly lower roasted peanut flavor, in addition to an off-flavor that was noted for samples with 1.5 % to 2 % candelilla wax. Therefore, it was determined that ricebran wax and sunflower wax (due to its similarity to rice bran wax) had the highest potential to produce a suitable product that prevents oil separation during storage and has suitable textural and flavor properties. These results will be useful for food companies that are seeking a non-caloric and zero-saturated fat alternative stabilizer for peanut butter, nut and seed butters, or other other food products where oil separation during storage is a problem.

Technical Abstract: Natural peanut butter was stabilized with 1 % to 2 % (by weight) with beeswax (BW), candelilla wax (CLW), rice bran wax (RBW), or sunflower wax (SFW) and the appearance, spreadability, mouthfeel and flavor attributes of these samples were evaluated by a trained sensory panel, using commercial stabilized peanut butter and a sample stabilized with hydrogenated cottonseed oil as a reference. The wax type and levels significantly (P < 0.05) influenced appearance, spreadability, firmness, mouthfeel, and flavor attributes. Samples with 1.5 % - 2.0 % CLW, or 1.0 -1.5 % RBW had the fewest differences in appearance and texture from the reference and commercial samples. However, an off-flavor was attributed to 1.5 % or higher CLW, so samples stabilized with BW or with 1.0 % – 1.5 % RBW had the fewest difference in flavor compared to the reference sample. Overall, samples stabilized with 1 % to 1.5 % RBW scored the closest to the commercial and reference samples. The responses of CLW, RBW, and SFW (which was only evaluated for appearance and spreadability) indicate that amounts of these waxes could be tailored in different products to achieve a product with desirable texture and flavor as well as stability to oil loss.