Effect of Pleurotus ostreatus powder on the nutritional characteristics of bread

Pleurotus ostreatus is one of the most produced edible mushrooms worldwide. It is a source of high quality proteins, rich in fiber, vitamins, minerals and essential amino acids. Several bioactive compounds have been identified in P. ostreatus, such as -glucans, with immunosuppressive and immunomodulatory activities, hypoglycemic and prebiotic effects. Aguamiel, obtained from Agave Salmiana, is a sweet-tasting liquid that can be used as a sugar replacer. Prebiotics such as fructo- oligosaccharides were found in its composition. Together, P. ostreatus and aguamiel, may be incorporated into food formulations increasing nutritional and functionality of final products. In this work, P. ostreatus powder (PO) and aguamiel (used as sucrose substitute) were incorporated into a bread. The work aimed to characterize physicochemically the bread obtained. Five bread formulations were produced to partially replace the wheat flour by the PO, as following 100:0, 95:5, 90:10, 85:15, 80:20 (wheat flour:PO, respectively). Aguamiel was incorporated as a sucrose substitute in all bread formulations. The proximate composition of the bread formulations and the PO itself was determined by the conventional method of AOAC (2000), including moisture, total ash, fat, protein and carbohydrate. Bromatological and physical analysis of the breads were evaluated, the hardness, specific volume and color of the different products were identified. Results showed that there was no significant difference neither in hardness nor in the moisture (25% - 32%) determined between formulations. The specific volume decreased, and the color saturation increased, by increasing the amount of PO incorporated in the bread. The nutritional value of the bread increased significantly (p> 0.05) with the addition of PO. The protein content increased from 1.1% to 1.5% ± 0.2. Also, crude fiber increased from 0.04% to 0.65% ± 0.25 and ashes from 2.5% to 3.8% ±0.6. The fat composition of the samples increased from 5% to 7% ± 1 and there was no significant difference in the content of carbohydrates (55% to 65% ± 5). PO used was a rich source of protein (22.3%), fiber (5.5%) and minerals (9.9%). P. ostreatus and aguamiel showed great potential to increase nutritional value of traditional bread.