Zmiany właściwości fizycznych chleba bezglutenowego pod wpływem dodatku suszonej lucerny

Celem pracy było określenie zmian właściwości fizycznych chleba bezglutenowego na bazie mąki ryżowej i kukurydzianej (1:1) pod wpływem dodatku suszonych liści lucerny. Lucernę w formie proszku dodawano do receptury chleba bezglutenowego w ilości 0, 2, 4, 6, 8 i 10%. Po wypieku określano podstawowe właściwości fizyczne chleba, cechy tekstury miękiszu (test TPA), barwę (L*a*b*) oraz wykonano jego ocenę organoleptyczną. Dodatek lucerny spowodował zmniejszenie wartości pH pieczywa z poziomu 5,1 (kontrolny) do 4,7 (10% lucerny). Istotne zmniejszenie objętości chleba bezglutenowego stwierdzono już przy 2% dodatku proszku lucerny. Dodatek lucerny w proszku zmienił barwę miękiszu, składowe L* i b* zmniejszały się, a wartość barwy a* wzrosła. Zaobserwowano zwiększenie twardości i sprężystości miękiszu chleba bezglutenowego dopiero po przekroczeniu 6 i 10% dodatku lucerny w proszku. Zastosowanie lucerny wpłynęło negatywnie na smak i zapach chleba, jednak – mając na uwadze jej walory zdrowotne – można zaakceptować 2 do 4% udziału tego surowca.

The aim of work was to determine the influence of alfalfa leaves powder addition directly into gluten-free bread recipe on physical and sensory properties of bread. The raw material for making control gluten-free bread included white rice flour and corn flour (1:1). Alfalfa leaves powder was added in the amounts of 2, 4, 6, 8 and 10% of the total gluten-free blend. The gluten-free dough was mixed of all the ingredients for 5 min. After mixing, the dough was immediately transferred into a pan and then subjected to proofing (30°C and 75–88% RH) for 40 min. The loaves were baked at 230oC for 45–50 min in a laboratory oven. The basic physical, texture (the TPA test) (hardness, springiness, chewiness), color (L*a*b*) and sensory (taste, aroma, texture and overall acceptability) properties were determined after baking. In comparison with control bread a significantly lower pH value was obtained, it changed from 5,1 (control) to 4,7 (10%). With an increased content of alfalfa, significant changes were noted in the volume of gluten-free bread. Volume of bread decreased with increasing the addition of alfalfa in the range from 0 to 10%. The lowest volume was obtained after adding 10% of alfalfa, but significantly lower volume was obtained already after using 2% of alfalfa powder. With an increased content of alfalfa powder, significant changes were noted in the color of bread crumb. Lightness component L* decreased with increasing the addition of alfalfa in the range from 0 to 10%. Parameter a* increased with the addition of alfalfa in the range from 6 to 10%. Value b* of color decreased significantly with 4% of alfalfa addition. Changes in the texture (hardness, springiness and chewiness) were also observed. The hardness increased significantly with increasing alfalfa powder addition as compared to control bread. Alfalfa powder addition at the level of 6% significantly increased hardness. There were no significant differences in the springiness of GFB with 0, 2, 4 and 6% share of alfalfa in bread formulation. The highest springiness was observed in gluten-free bread formula containing 10% of alfalfa leaves powder. Chewiness of crumb significantly increased after adding 2% of alfalfa leaves powder. The results confirm the possibility of the use of alfalfa powder in the production of GFB. Because of the unpleasant taste an acceptable gluten-free bread can be obtained by adding from 2 to 4% of the alfalfa leaves powder.