Baking Quality Assessment of Twenty Whole Grain Oat Cultivar Samples

Whole grain oat has become an increasingly popular baking ingredient. Still, oat baking poses many industrial challenges because the baking quality criteria have not been set for whole grain oat flours, and cultivar variation remains unknown. We aimed to assess the baking quality variation of twenty whole grain oat cultivar samples, and to identify the factors that caused the variation. It was hypothesised that by optimising the water absorption of the dough (i.e., dough yield) by test baking method, the best baking potential could be achieved for all oat cultivar samples. The baking trials were conducted as whole oat baking, without wheat or gluten additions. In most of the samples, good baking quality was obtained by dough yield optimisation. The highest specific volumes (1.9–1.93 mL/g) and best crumb properties were achieved in the samples with the highest optimal dough yields, 205. However, baking quality varied, as all samples could not be baked with good quality at high dough yields. Additionally, small median particle size and high fat content of the oat flours were related to good baking properties of whole grain oat at optimised dough yield (p < 0.05). These findings can benefit the development and the optimisation of industrial oat baking processes

Baking Quality Assessment of Twenty Whole Grain Oat Cultivar Samples

Whole grain oat has become an increasingly popular baking ingredient. Still, oat baking poses many industrial challenges because the baking quality criteria have not been set for whole grain oat flours, and cultivar variation remains unknown. We aimed to assess the baking quality variation of twenty whole grain oat cultivar samples, and to identify the factors that caused the variation. It was hypothesised that by optimising the water absorption of the dough (i.e., dough yield) by test baking method, the best baking potential could be achieved for all oat cultivar samples. The baking trials were conducted as whole oat baking, without wheat or gluten additions. In most of the samples, good baking quality was obtained by dough yield optimisation. The highest specific volumes (1.9–1.93 mL/g) and best crumb properties were achieved in the samples with the highest optimal dough yields, 205. However, baking quality varied, as all samples could not be baked with good quality at high dough yields. Additionally, small median particle size and high fat content of the oat flours were related to good baking properties of whole grain oat at optimised dough yield (p < 0.05). These findings can benefit the development and the optimisation of industrial oat baking processes

Genotypic differences of storage proteins in four Scandinavian spring wheat cultivars during seed development

Wheat (Triticum aestivum L.) is grown under a wide range of climatic conditions. Therefore, it is necessary to understand the underlying physiological phenomena which affect the quality of grain yield. The aim ofthis project was to study the interactions between cultivars in theiraccumulation and relative concentrations of the different protein groups of storage proteins at various stages of wheat grain development. Yield components, protein quantity and the quality of flour were examined. The study was carried out at the University of Helsinki, Department of Plant Production during 1989-1990. The cultivars used were Heta, Ruso, Reno and Kadett. Innorthern latitudes the early maturity class of a genotype is an important selection criterion associated with good breadmaking quality. The short grain filling period leads to a high rate of accumulation ofhigh molecular weight glutenins, because it coincides with a rapid expansion of the endosperm in the middle of grain filling. The associated yield loss in these cultivars may be compensated by higher number of grains per ear. Therefore, selection ofproductive wheat lines with earlymaturity, high protein concentration and high relative amount ofhigh molecular weight glutenins, and high grain number per ear instead of high kernel weight may lead to more stable yield and improved breadmaking quality

The role of hydrothermal treatment (steaming and tempering) parameters on oat groat, flake and flour properties

Peer reviewe

Barley C-Hordein as the Calibrant for Wheat Gluten Quantification

The lack of certified reference materials has been one major challenge for gluten quantification in gluten-free products. In this study, the feasibility of using barley C-hordein as the calibrant for wheat gluten in R5 sandwich enzyme-linked immunosorbent assay (ELISA) was investigated. The gluten composition and total gluten R5 reactivity ranged largely depending on the genotypes and the growing environment. The conversion factor of gliadin to gluten averaged 1.31 for common wheat, which is smaller than the theoretical factor of 2. Each gluten group had varying reactivity against the R5 antibody, where ω1.2-, γ- and α-gliadins were the main reactive groups from wheat gluten. A mixture of wheat cultivars or one single cultivar as the reference material can be difficult to keep current. Based on the average R5 reactivity of total gluten from the 27 common wheat cultivars, here we proposed 10% C-hordein mixed with an inert protein as the calibrant for wheat gluten quantification. In spiking tests of gluten-free oat flour and biscuits, calibration using 10% C-hordein achieved the same recovery as the gliadin standard with its cultivar-specific conversion factor. For its good solubility and good affinity to the R5 antibody, the application of C-hordein increases the probability of developing a series of reference materials for various food matrices

Barley C-Hordein as the Calibrant for Wheat Gluten Quantification

The lack of certified reference materials has been one major challenge for gluten quantification in gluten-free products. In this study, the feasibility of using barley C-hordein as the calibrant for wheat gluten in R5 sandwich enzyme-linked immunosorbent assay (ELISA) was investigated. The gluten composition and total gluten R5 reactivity ranged largely depending on the genotypes and the growing environment. The conversion factor of gliadin to gluten averaged 1.31 for common wheat, which is smaller than the theoretical factor of 2. Each gluten group had varying reactivity against the R5 antibody, where ω1.2-, γ- and α-gliadins were the main reactive groups from wheat gluten. A mixture of wheat cultivars or one single cultivar as the reference material can be difficult to keep current. Based on the average R5 reactivity of total gluten from the 27 common wheat cultivars, here we proposed 10% C-hordein mixed with an inert protein as the calibrant for wheat gluten quantification. In spiking tests of gluten-free oat flour and biscuits, calibration using 10% C-hordein achieved the same recovery as the gliadin standard with its cultivar-specific conversion factor. For its good solubility and good affinity to the R5 antibody, the application of C-hordein increases the probability of developing a series of reference materials for various food matrices

Oat Protein Concentrates with Improved Solubility Produced by an Enzyme-Aided Ultrafiltration Extraction Method

The aim of this study was to develop an extraction method to produce highly functional oat protein concentrates. We investigated the possibility of combining enzyme-aided slightly alkaline (pH 8.0) extraction with ultrafiltration and subsequent diafiltration for concentration of the extracted oat proteins. A further aim was to study how the deamidation of oat proteins with protein-glutaminase (PG) improves the solubility of proteins as a function of the following parameters: pH (6.0–9.0), enzyme dosage (4–20 U/g protein), and incubation time (1–4 h) with response surface methodology (RSM). Furthermore, we investigated selected functional properties, such as heat-induced gelation and solubility, of the oat protein concentrates. The chosen parameters for the enzymatic deamidation pre-treatment process by PG were as follows: pH 8.0, dosage 11.0 U/g protein, and an incubation time of 4 h (1 h at native pH and 3 h at pH 8.0). Two oat protein concentrates were produced, non-deamidated and ultrafiltered, and deamidated and ultrafiltered, with protein concentrations of 45.0 and 52.4%, respectively. The solubility of both oat protein concentrates was significantly improved at neutral and slightly alkaline pH compared to the solubility of proteins extracted from the starting material. Additionally, both oat protein concentrates produced equally strong heat-induced gel-like structures at a protein concentration of 10%

Gelation of cereal β-glucan at low concentrations

Viscosity of cereal beta-glucan during digestion is considered to be a vital factor for its health effects. Thus, studies on solution properties and gelation are essential for understanding the mechanisms of the beta-glucan functionality. The aim of this study was to investigate the effect of the dissolution temperature on gelation of cereal beta-glucan at low concentrations that are relevant for food products. The rheological properties of oat and barley beta-glucans (OBG and BBG) using three dissolution temperatures (37 degrees C, 57 degrees C and 85 degrees C) at low concentration (1.5% and 1%, respectively) were studied for 7 days. Additionally, the beta-glucans were oxidised with 70 mM H2O2 and 1 mM FeSO4 x 7H(2)O as a catalyst, to evaluate the consequence of oxidative degradation on the gelation properties. The study showed that dissolution at 85 degrees C did not result in gelation. The optimal dissolution temperature for gelation of OBG was 37 degrees C and for gelation of BBG 57 degrees C. At these temperatures, also the oxidised OBG and BBG gelled, although the gel strength was somewhat lower than in the non-oxidised ones. Gelation was suggested to require partial dissolution of beta-glucan, which depended on the molar mass and aggregation state of the beta-glucan molecule. Therefore, the state of beta-glucan in solution and its thermal treatment history may affect its technological and physiological functionality. (C) 2017 Elsevier Ltd. All rights reserved.Peer reviewe

Liquefaction of hydrothermally pretreated wheat straw at high-solids content by purified Trichoderma enzymes

Peer reviewe

Tattari ja kaura yhdistyvät leivässä

Gluteenittoman leivonnan haasteena on taikinan sitkottomuus. Taikina on tarttuvaa ja sillä on heikkokaasunpidätyskyky. Tämän vuoksi monet kaupalliset leivät ovat heikkoja rakenteeltaan, huokoskokoon epätasainen, tilavuus jää usein pieneksi ja sisus on leikatessa mureneva. Sisuksen mureneminenaiheutuu leivän nopeasta vanhenemisesta, minkä vuoksi monet gluteenittomat leivät myydäänpakasteina. Valitettavan usein gluteenittomien leipien heikkoutena on myös niiden mauttomuus.Helsingin yliopistossa, elintarviketeknologian laitoksella toteutettiin Maajaelintarvikkeidentutkimuskeskuksen (MTT) 'Terveyttä tattarista' hankkeen osaprojekti `Tattarikauraleivänkehittäminen erityisruokavalioille´. Tavoitteena oli luoda tuote, joka täyttää samat kriteerit mitävehnäleivältäkin vaaditaan – hyvä maku, rakenne ja säilyvyys. Tärkeä tekijä oli myös tuotteenterveydellisyys ja kotimaisuus, minkä vuoksi leivonnassa käytetyt jauhot olivat kotimaisiatäysjyväjauhoja.Tattarin käytössä yksi suurimpia haasteita oli sille ominainen voimakas maku. Tämän vuoksi tattari sairinnalleen kauran. Kauran pehmeä maku yhdistettynä tattarin voimakkaaseen makuun tuotti uuden,maukkaan leivän. Leivässä voi maistaa myös hieman hapanleivästä tuttua happamuutta. Tämä ontulosta valmistusprosessista, joka hyödyntää perinteistä vehnätöntä leivontateknologiaa; osa jauhoistaon ensin keitetty ja tämän jälkeen fermentoitu eli hapatettu maitohappobakteereilla ennen taikinaanlisäämistä. Keittämällä osa jauhoista voitiin vaikuttaa taikinan käsiteltävyyteen ja leivän rakenteeseen.Fermentoinnissa muodostuvat hapot antoivat leivälle miedon happaman maun, parantaen samallamyös säilyvyyttä. Fermentoitu kaura taittoi tehokkaasti tattarin voimakasta makua.Gluteenittomassa leivonnassa käytetään yleisesti vettä sitovia hydrokolloideja parantamaan taikinankäsiteltävyyttä ja kaasunpidätyskykyä. Hydrokolloidien avulla saadaan gluteenittomasta leivästäkosteampi, tasahuokoinen ja vähemmän mureneva. Leivonnassa käytetty hydrokolloidi,karboksimetyyliselluloosa, paransi huomattavasti taikinan käsiteltävyyttä ja optimoi leivänhuokoskoon.Leivän valmistuksessa haluttiin käyttää myös tattarilesettä, jossa on runsaasti mm. fagopyritoleja.Fagopyritolit ovat rakenteeltaan ihmisen insuliinin kaltaisia yhdisteitä. Fagopyritoleista erityisesti Dchiroinositolinon havaittu alentavan veren seerumin glukoositasoa ja näin vaikuttavan edullisestidiabeteksen hoidossa. Tattarille ominainen maku voimistui huomattavasti tattarileseen lisäyksenmyötä ja tässä projektissa käytetty leselisäys (6 %) oli aistinvaraisesti korkein hyväksyttävä. Leseenkäyttöä rajoittikin ensisijaisesti sen voimakas maku eivätkä leivontateknologiset ominaisuudet.Tutkimus osoitti gluteenittoman tattarileivonnan hyötyvän keitetystä ja fermentoidustakauramateriaalista. Tämä avulla leipiin saatiin hyvä tilavuus ja rakenne. Tattarin voimakasta makuavoitiin pehmentää kauran avulla, mutta edelleen makua taittoi fermentoitu kauravelli. Hydrokolloidillaoptimoitiin taikinan käsiteltävyys ja leivän huokosrakenne. Tattarikauraleipä säilyi rakenteeltaanhyvänä ja homeettomana kolmen päivän seurantakokeiden aikana