Almonds (Prunus dulcis (Mill.) D.A. Webb or Amygdalus communis L.) are used in the preparation of bakery and confectionery products including almond cookies, marzipan and almond milk. The first productive step consists of blanching and peeling the almonds, so as to remove the skin. Skins account for 6-8% of the seed and are mainly destined to cattle feeding. Blanching water represents a waste, involving a disposal expense for the producers. Therefore, in this work we evaluated the potential of by-products of almond processing, namely blanched skins and blanching water, as ingredients of functional bakery products, due to the presence of phenolic compounds and, in the skin, also fiber. We started by optimizing skin drying; then we quali-quantitative determined the phenolic compounds; finally we assessed the impact of by-products on the rheology of composite dough with wheat flour. Oven-drying at 60 °C for 30 min was less-time consuming than other time-temperature combinations tested and retained good odor notes. Moreover, this drying condition allowed to maintain higher content of phenolics (814 µg/g d.m. by HPLC) and higher antioxidant activity than sun-drying. Blanching water, on the other hand, had a content of phenolic compounds accounting for 917 µg/mL. The alveograph and farinograph indices of composite dough was altered by adding dried almond skins at doses higher than 30 and 50 g/kg, respectively. Blanching water did not changed significantly these indices. In conclusion, almond skins could be used at percentages lower than 30% or in bakery products tolerating a weak gluten network, such as cookies. Blanching water, instead, could be added to any kind of bakery good with no rheological negative effect.
POTENTIAL OF ALMOND BY-PRODUCTS FOR FUTURE FUNCTIONAL BAKERY PRODUCTS
Barbara LADDOMADA;Giovanni MITA;
2018
Abstract
Almonds (Prunus dulcis (Mill.) D.A. Webb or Amygdalus communis L.) are used in the preparation of bakery and confectionery products including almond cookies, marzipan and almond milk. The first productive step consists of blanching and peeling the almonds, so as to remove the skin. Skins account for 6-8% of the seed and are mainly destined to cattle feeding. Blanching water represents a waste, involving a disposal expense for the producers. Therefore, in this work we evaluated the potential of by-products of almond processing, namely blanched skins and blanching water, as ingredients of functional bakery products, due to the presence of phenolic compounds and, in the skin, also fiber. We started by optimizing skin drying; then we quali-quantitative determined the phenolic compounds; finally we assessed the impact of by-products on the rheology of composite dough with wheat flour. Oven-drying at 60 °C for 30 min was less-time consuming than other time-temperature combinations tested and retained good odor notes. Moreover, this drying condition allowed to maintain higher content of phenolics (814 µg/g d.m. by HPLC) and higher antioxidant activity than sun-drying. Blanching water, on the other hand, had a content of phenolic compounds accounting for 917 µg/mL. The alveograph and farinograph indices of composite dough was altered by adding dried almond skins at doses higher than 30 and 50 g/kg, respectively. Blanching water did not changed significantly these indices. In conclusion, almond skins could be used at percentages lower than 30% or in bakery products tolerating a weak gluten network, such as cookies. Blanching water, instead, could be added to any kind of bakery good with no rheological negative effect.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
