RESUMEN
In bread, NaCl plays a number of roles including improving flavor, functionality, dough handling, and prevention of sticky dough. Its reduction can create significant processing challenges. As such, the dough handling properties for four wheat cultivars (Pembina, Roblin, McKenzie, and Harvest) were investigated as a function of NaCl (0-4%) level. In terms of dough rheology, both cultivar and NaCl level were significant factors. The maximum deformation (Jmax ) in the dough decreased with increasing NaCl levels, indicating that the gluten network became stronger so that it was able to resist the imposed stress. For extensibility, increasing the levels of NaCl resulted in increased resistance to extension for all cultivars. Dough stickiness was shown to be both cultivar and salt level dependent, with weaker cultivars showing higher stickiness. Findings for water association indicated that with the addition of NaCl there was less free water among the different cultivars and an increase in the water associated with the starch-fraction. Dough morphology measurements supported rheology trends; the stronger dough producing cultivars created more elongated protein polymers with a unidirectional network whereas the weaker cultivars created porous multidirectional networks. Overall, Pembina and Roblin formed stronger gluten networks than McKenzie and Harvest, however, the effect of NaCl level was shown to be cultivar dependent. Findings indicate that careful cultivar selection will help mitigate challenges in dough handling within a reduced NaCl environment.
Asunto(s)
Pan/análisis , Cloruro de Sodio , Triticum , Agua , Harina/análisis , Manipulación de Alimentos/métodos , Glútenes , Reología , AlmidónRESUMEN
For many years, the baking industry has been using chemical improvers as a way for compensating for flour quality variation due to growing conditions or wheat cultivar. However, the replacement of chemical dough improvers with natural ingredients or processing aids (i.e. enzymes) allows for the production of 'cleaner label' products. In the present research, dough and bread properties (mixing time, oven rise, loaf volume, crumb firmness and C-cell parameters) were analysed as a function of wheat cultivar (Glenn, Harvest, Lillian, CDC Plentiful and Stettler), additive-type (ascorbic acid, azodicarbonamide, glucose oxidase and fungal xylanase) and concentration. Overall, the cultivar Glenn appeared to have improved baking performance relative to the other cultivars, regardless of the additive and additive concentration. On the other hand, Stettler showed poorer baking quality and performance even with the addition of oxidizers and enzymes in relation to the control. The concentration of additive was found to have little or no effect on improving baking properties within each cultivar. Enzymes had similar or better performance than oxidizers in most cases.
Asunto(s)
Pan , Enzimas , Manipulación de Alimentos , Oxidantes , Triticum , Pan/análisis , Pan/normas , Canadá , Enzimas/metabolismo , Harina/clasificación , Manipulación de Alimentos/métodos , Manipulación de Alimentos/normas , Oxidantes/farmacología , Triticum/clasificación , Triticum/efectos de los fármacos , Triticum/metabolismoRESUMEN
The influence of select salts from the lyotropic series (NH4Cl, KCl, NaCl, MgCl2, CaCl2, and MgSO4) on the rheology and stickiness of dough prepared from a strong (Pembina) and a weak (Harvest) hard red spring wheat flour were examined at a 1 and 2% salt levels, with water mobility and water association with different dough components also being assessed at the 1% salt level. Overall, Pembina was found to develop stronger gluten networks that were more resilient than those of Harvest as evident from a lower tan δ and less compliance during shear creep recovery rheology. However, the effect of salt-type differed based on cultivar. Pembina showed lower dough stickiness than Harvest in all cases. NH4Cl decreased dough stickiness the most for both cultivars. The use of alternative salts affected the association of water with the starch-fraction and gluten-fraction in doughs, and this effect was cultivar-dependent.
Asunto(s)
Pan/análisis , Cloruro de Sodio/química , Triticum/química , Harina/análisis , Manipulación de Alimentos , Glútenes/química , Dureza , Agua/químicaRESUMEN
What is universal about music, and what varies? We built a corpus of ethnographic text on musical behavior from a representative sample of the world's societies, as well as a discography of audio recordings. The ethnographic corpus reveals that music (including songs with words) appears in every society observed; that music varies along three dimensions (formality, arousal, religiosity), more within societies than across them; and that music is associated with certain behavioral contexts such as infant care, healing, dance, and love. The discography-analyzed through machine summaries, amateur and expert listener ratings, and manual transcriptions-reveals that acoustic features of songs predict their primary behavioral context; that tonality is widespread, perhaps universal; that music varies in rhythmic and melodic complexity; and that elements of melodies and rhythms found worldwide follow power laws.
Asunto(s)
Antropología Cultural , Música , Canto , Percepción Auditiva , Conducta , Comparación Transcultural , Baile , Humanos , Cuidado del Lactante , Recién Nacido , Amor , Psicoacústica , ReligiónRESUMEN
The overall goal of this research was to examine the mechanical, water vapor barrier properties and opacity of films prepared using legume protein concentrates (faba bean, pea, lupin, lentil, and soy) as a function of glycerol concentration (50, 75, or 100% [wt/wt]-relative to the protein weight). Overall, tensile strength (TS) decreased with increasing glycerol concentration, whereas tensile elongation (TE) and water vapor permeability (WVP) increased with increasing glycerol concentration. Film opacity was independent of glycerol concentration. The effect of protein-type varied considerably depending on the functional property of the film being measured; TS was greatest with faba bean and lowest with lupin, whereas TE was highest for pea, and lowest for soy. Lentil protein films had considerably higher WVP, at the 100% glycerol concentration, as compared to the other protein concentrates. Findings from this study indicate that legume protein concentrates are capable of forming biodegradable, edible films. Overall, pea protein concentrate films showed the most promise for application in terms of strength, elongation, and moisture barrier properties.
Asunto(s)
Fenómenos Químicos , Películas Comestibles , Embalaje de Alimentos , Glicerol/química , Proteínas de Guisantes/química , Permeabilidad , Proteínas de Plantas/química , Proteínas de Soja/química , Vapor , Resistencia a la TracciónRESUMEN
The effects of transglutaminase (TG) and glucose oxidase (GO) on the handling properties of model bread dough were examined at both normal (2% wt. by flour) and reduced (1% wt.) sodium chloride (NaCl) levels using two Canada Western Red Spring (CWRS) cultivars; Pembina and Harvest. The reduction of NaCl level had negative effects on dough rheology and stickiness, however, the inclusion of GO (0.001 and 0.01% by flour weight) or TG (only at the 0.5% by flour weight inclusion) was able to improve dough strength and reduce stickiness. GO appeared to be more effective than TG (at 0.01%) at equivalent concentrations for improving dough-handling properties. Flour cultivar had significant effects; Harvest flour (weaker) was more impacted by salt reduction and enzyme inclusion compared to Pembina flour (stronger). Crosslinking assays showed significant differences in glutenin macropolymer (GMP) content in dough prepared with GO, and dough prepared with different flours. Additionally, significantly fewer free thiol groups were found in dough produced with GO compared to dough without any enzymes and those with TG. GO appears to have potential for use as a bread improver to reduce stickiness and improve the strength of bread dough produced at lower salt concentrations, especially for dough prepared with weaker flour cultivars.