Influence of the addition of extruded flours on rice bread quality

Producción CientíficaThe extrusion may improve coeliac bread quality by modifying the functional properties of flour. This study investigates the influence of the substitution of 10% of rice flour by extruded rice flours (three intensities of treatment and two particle sizes) on the characteristics of gluten-free bread (specific volume and texture) at constant consistency. The microstructure and rheology of the doughs obtained and their behaviour during fermentation have also been analysed. The extruded flours increase dough consistency, and the effect is more noticeable with increasing intensities of treatment. The use of extruded flours requires the addition of a larger volume of water to obtain a constant consistency. The addition of extruded flour decreases dough development, producing a lower specific volume and greater bread hardness. This effect is minimized by increasing the particle size. The staling of bread from 24 to 72 hours is less noticeable with a larger particle size. PRACTICAL APPLICATIONS This study evidences that the use of extruded flours in rice bread making allows increasing dough hydration and therefore the bread yield while decreasing bread staling. However, the correct selection of extrusion treatment and flour particle size is essential to achieve appropriate results, being preferable the use of coarse flours with more intense extrusion treatment

Protein composition and nutritional aspects of pea protein fractions obtained by a modified isoelectric precipitation method using fermentation

Pea albumins are promising for their nutritional, biological, and techno-functional properties. However, this fraction is usually discarded in the industry due to its low protein content compared to globulin fraction and the presence of some anti-nutritional compounds. In the present study, we used an alternative method of pea protein extraction based on alkaline solubilization/isoelectric precipitation in which the reduction of pH was achieved by lactic acid fermentation using specific starters instead of mineral acids. Hence, the main objective of this study was to examine the protein profile and the content of anti-nutritional and nutritional active compounds in pea albumin-rich fractions obtained by the isoelectric extraction method without (control) or with fermentation with different lactic acid bacteria (Streptococcus thermophilus, Lactiplantibacillus plantarum, and their co-culture). Different pea cultivars (Cartouche, Ascension, and Assas) were used here for their differences in protein profile. The results revealed a higher total nitrogen content in albumin-rich fraction for fermented samples and, in particular, for co-culture. The majority of total nitrogen was determined as non-protein (~50%), suggesting the degradation of proteins by LAB to small peptides and amino acids, which were solubilized in the soluble fraction (albumin) as confirmed by size exclusion chromatography (SEC-HPLC) analysis. Moreover, the higher antioxidant activity of fermented albumin samples was attributed to the production of small peptides during extraction. Lactic acid fermentation also resulted in a significant reduction of trypsin inhibitor activity, α-galactoside, and phytic acid content of this fraction compared to control

Effect of the addition of extruded wheat flours on dough rheology and bread quality

Producción CientíficaExtruded wheat flours, due to their increased water absorption capacity, constitute an opportunity to increase bread output in bakery production. However extrusion may modify dough and bread characteristics. The aim of this study was to investigate the effect of the substitution of 5% of the wheat flour by extruded wheat flour (produced with different time-temperature extrusion treatments) on dough mixing, handling and fermentation behaviour and bread volume, shape, texture and colour. The RVA curves indicate that extrusion intensity increases with increasing temperature or water content. Water absorption capacity rises with increasing treatment intensity, but dough stability tends to decrease. Adding extruded flours decreases dough extensibility but increases tenacity and gas production. Differences in dough structure were observed on photomicrography, though there were no clear differences in bread quality. These results indicate that it is possible to obtain adequate dough and bread characteristics using dough with 5% extruded wheat flour

Use of wheat, triticale and rye flours in layer cake production

In this study, the capacity of obtaining high quality layer cakes from rye and triticale lines was analysed and compared to wheat lines. The samples were characterised considering grain hardness, flour composition and quality parameters as protein, pentosan, damaged starch, pasting viscosity and functional predictive test - solvent retention capacity test. Cakes were analysed in weight, symmetry, volume, volume index (VI) by measuring the height in different points of the cake, crust and crumb colour, crumb structure and texture. Wheat and triticale cakes showed similar characteristics. Rye cakes showed higher volume and lower weight than those with crumbs darker in colour, higher adhesiveness, springiness and resilience. The multiple regression analysis was used to develop an equation for cake volume index prediction. The best-fit linear regression model was: VI = 14.75 - 0.14 protein + 0.93 water soluble pentosan - 0.27 total pentosan. Despite the differences, high quality cakes can be elaborated with rye, triticale and soft wheat cultivars. © 2010 The Authors. Journal compilation © 2010 Institute of Food Science and Technology.Fil: Oliete, Bonastre. Universidad de Valladolid; EspañaFil: Perez, Gabriela Teresa. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Gómez, Manuel. Universidad de Valladolid; EspañaFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Moiraghi, Malena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Leon, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentin

Odnos broja somatskih stanica i sastav i koagulacijska svojstva ovčjeg mlijeka

The relationship between somatic cell count (SCC) and raw milk composition and its coagulation properties measured at native or standardised pH values were investigated in Manchega ewes’ milk. A total of 84 bulk tank milk samples from flocks included in the National Association of Manchega Sheep Breeders were used. According to their SCC, milk samples were divided into three terciles named low (562±138 cells/mL), medium (956±115 cells/mL) and high (1705±428 cells/ mL) SCC groups. Within each SCC group, two pH treatments were applied before determining coagulation properties (rennet clotting time, curd firming time and curd firmness): no acidification of milk (coagulation at native pH) and acidification of milk at pH 6.5. Native milk pH significantly increased (P0.05) by SCC, protein content tended to be higher in the high SCC group (P=0.05) and lactose content was significantly lower (P0,05) na udjel masti, dok je udjel proteina bio veći u grupi s visokim BSS (P=0,05), a udjel laktoze bio je signifikantno niži (P<0,05) u toj skupini. Kod prirodne pH vrijednosti mlijeka, visoki BSS utjecao je na duže vrijeme zgrušavanja mlijeka sirilom, sporije učvršćivanje gruša i na manju čvrstoću gruša nakon 30 min od dodatka sirila, u odnosu na skupinu u kojoj je BSS bio nizak i srednji (P<0,05). Standardizacija pH mlijeka na 6,5 prije dodavanja sirila anulirala je (P<0,05) negativan utjecaj visokog BSS na koagulacijska svojstva mlijeka. Može se zaključiti da su, unatoč činjenici kako je acidifikacija mlijeka prije zgrušavanja poboljšala koagulacijske osobine mlijeka s visokim BSS, daljnja istraživanja potrebna kako bi se utvrdila senzorska svojstva sira proizvedenog takvim postupkom

Pea Protein Extraction Assisted by Lactic Fermentation: Impact on Protein Profile and Thermal Properties

International audienceAlthough pea protein has been widely explored, its consumption is still limited by undesirable sensory characteristics and low solubility. All these properties can be modified during protein extraction process. Besides, previous studies showed that lactic acid bacteria (LAB) have a positive effect on legume protein ingredients in terms of flavor and functional properties. Hence, the objective of this work was to explore an alternative extraction method based on alkaline extraction/isoelectric precipitation (AEIEP) resulting in globulin-rich and residual albumin-rich fractions. Here, the decrease in pH was achieved by lactic fermentation instead of mineral acid addition. Different bacteria strains (Streptococcus thermophilus, Lactobacillus acidophilus and Bifidobacterium lactis) have been used alone or in co-culture, and the results were compared with the usual acidification. The extraction assisted by fermentation led to the increase by 20-30% in protein content/yield of the albumin fraction, meaning that the solubility of the extracted pea protein was increased. This result could be explained by the proteolytic activity of bacteria during lactic fermentation. Therefore, the thermal denaturation properties of the isolated protein fractions measured by differential scanning calorimetry could be mainly ascribed to differences in their polypeptide compositions. In particular, higher denaturation enthalpy in globulin fractions after fermentation compared to AEIEP (~15 J/g protein vs. ~13 J/g protein) revealed the relative enrichment of this fraction in pea legumins; a higher part of 7S globulins seemed to be consumed by lactic acid bacteria

Effect of Lactic Acid Fermentation on Legume Protein Properties, a Review

International audienceLegume proteins have a promising future in the food industry due to their nutritional, environmental, and economic benefits. However, their application is still limited due to the presence of antinutritional and allergenic compounds, their poor technological properties, and their unpleasant sensory characteristics. Fermentation has been traditionally applied to counteract these inconveniences. At present, lactic acid fermentation of legumes is attracting the attention of researchers and industry in relation to the development of healthier, tasty, and technologically adapted products. Hence, we aimed to review the literature to shed light on the effect of lactic acid fermentation on legume protein composition and on their nutritional, functional, technological, and sensorial properties. The antimicrobial activity of lactic acid bacteria during legume fermentation was also considered. The heterogenicity of raw material composition (flour, concentrate, and isolate), the diversity of lactic acid bacteria (nutriment requirements, metabolic pathways, and enzyme production), and the numerous possible fermenting conditions (temperature, time, oxygen, and additional nutrients) offer an impressive range of possibilities with regard to fermented legume products. Systematic studies are required in order to determine the specific roles of the different factors. The optimal selection of these criteria will allow one to obtain high-quality fermented legume products. Fermentation is an attractive technology for the development of legume-based products that are able to satisfy consumers’ expectations from a nutritional, functional, technological, and sensory point of view

Improvement of the techno-functional properties of pea proteins by microfluidization

International audienceThe use of pea (Pisum sativum (L.)) proteins in the food industry is still limited despite their good environmental sustainability, heath-oriented composition, reliable origin and stable price. However, one of the most important limitations is their low solubility which determines a number of their techno-functional properties. Microfluidization is a non-thermal emerging technology that may modify the structure and the techno-functional properties of pea proteins. Microfluidization combines high shear forces due to the stream speed and direction; impact forces from collisions with the walls and with the fluid itself; and turbulence inside the chamber. The objective of this work was to evaluate the effects of dynamic high pressure (microfluidization) on the techno-functional properties of commercial pea protein isolates. Microfluidization was performed by using a Microfluidizer processor model LM10 (Microfluidics, Newton, MA, USA) provided with a Z-type chamber. Solubility was clearly increased when applying microfluidization at 100MPa. Microfluidization also improved the least gelation concentration by thermal and acidic treatments, and the interfacial tension. However no clear effect was observed in the foaming capacity. This work permitted to conclude that the effect of microfluidization depends on the sample characteristics, on the environmental conditions, and on the microfluidization parameters

Studies on cake quality made of wheat-chickpea flour blends

9 pages, 1 figures, 6 tables. Published online 23 December 2007.Legume flours, due to their amino acid composition and fibre content are ideal ingredients for improving the nutritional value of bread and bakery products. In this study, the influence of the total or partial replacement of wheat flour by chickpea flour on the quality characteristics of two kinds of cake was analyzed. The effects of the chickpea variety and the kind of flour used (white or whole) were also considered. Volume, symmetry, chroma, and crust and crumb L* diminished when increasing the amount of chickpea flour. The replacement of wheat flour by chickpea flour also induced an increase in the initial firmness but cohesiveness and resilience diminished, increasing the tendency to hardening. Among the studied varieties, Pedrosillano and Sinaloa produced cakes with the highest volume. Those varieties also gave layer cakes with the lowest firmness, gumminess and chewiness. White flours produced sponge cakes with higher volume and symmetry than whole flours. No significant differences, however, were observed in layer cakes between white and whole flours. In both layer and sponge cakes, white flour produced cakes with lower firmness, gumminess and chewiness than whole flours.This work was financially supported by the Spanish Ministerio de Educación y Ciencia Project (MCYT, AGL2005-05192-C04).Peer reviewe

Microfluidization as Homogenization Technique in Pea Globulin-Based Emulsions

International audienceThe effect of microfluidization pressure (50, 70 and 130 MPa) during emulsification on the properties of native (NP) and soluble thermally aggregated (SA) pea (Pisum sativum L.) globulin-based emulsions at neutral pH was studied. Emulsions were characterized by interfacial protein-adsorption capacity, charge, emulsifying and flocculation properties, and creaming stability. NP- and SA-based emulsions were highly flocculated. Floc size decreased when increasing the microfluidization pressure during emulsification. Shear, turbulence, and collisions due to microfluidization induced modifications in the protein/aggregate association at the O/W interface and decreased the oil droplet size. SA-based emulsions showed higher floc size and smaller oil droplet size and revealed a more effective adsorption of SA at the O/W interface than NP. Creaming stability in NP-based emulsions decreased when increasing microfluidization pressure probably as a consequence of depletion-flocculation phenomena. On the contrary, creaming stability in SA-based emulsions improved when increasing homogenization pressure as a result of the formation of a gel-like network. Microfluidization could be used to modulate the emulsifying properties of pea globulin depending on their initial denaturation state