Bioactive compounds in spelt bread

In this study the milling and baking characteristics of ten strains of spelt wheat (Triticum aestivum ssp. spelta) originated from Polish breeding were shown. Evaluation of the grain included test weight, vitreousness and hardness. White spelt flour with extraction rate of 65–70% was characterized through the analyses of ash, protein, wet gluten and starch contents as well as Farinograph test, Amylograph test and falling number. Most of spelt wheat varieties investigated demonstrated good milling properties and high baking quality. The spelt breads were analyzed for their potential beneficial components, including total phenolic compounds (TPC) and flavonoids (TF), tocopherols (T) and tocotrienols (T3), inositol phosphates (IP) and reduced (GSH) and oxidized (GSSG) glutathione, and then compared to commercial wheat roll based on wheat flour with extraction rate of approximately 70%. The comparison of the bioactive compounds content between spelt breads and wheat showed a similar level of TPC, TF and GSH. The tocopherols and tocotrienols content in spelt bread was about twice lower when compared to wheat roll. Moreover, spelt wheat bread formulated from flour originated from STH 915 strain showed higher content of inositol phosphates when compared to wheat roll and to those breads from flour of STH 975 and STH 974 strains.     

Antioxidants in thermally treated buckwheat groats

The seeds of buckwheat (Fagopyrum esculentum Moench L.) were dehulled and then, following milling, extruded on a counter rotating, twin-screw extruder with the different barrel temperature profiles: 120, 160, and 200 degrees C. After extrusion cooking process, the following compounds were analyzed: free and conjugated phenolic acids, total polyphenols (TPC), tocopherols (T) and tocotrienols (T3), inositol phosphates (IP), reduced glutathione (GSH), and melatonin (MLT). The antioxidant capacity and superoxide dismutase-like activity (SOD-like activity) were determined in the groats and extrudates. Extrusion caused a significant decrease in all the compounds tested, except for phenolic acids. The content of IP decreased by 13%, that of GSH by 42%, and that of T + T3 by 62%. A three-fold lower level of MLT and TPC was noted whereas the SOD-like activity disappeared when compared to the nonextruded material. A two-fold higher content of phenolic acids (free and released from ester bonds) was observed. In spite of the clear decrease in the investigated antioxidants, the extruded dehulled buckwheat seeds contained still significant content of bioactive compounds, which resulted in as little as an average 10% decrease of the antioxidant capacity.     

Breadmaking and Storage of Various Wheat Fractions Affect Vitamin E

The vitamin E loss during baking of two types of industrially baked breads was studied. Neither scalding nor fermentation reduced the vitamin E content. However, the sour dough preparation and dough-making resulted in 20-60% reduction in the content of tocopherols and tocotrienols. In addition the vitamin E yield in the doughs and the French bread when using two different extraction methods were compared. The two methods showed similar results for flours and doughs, but indicated differences after the baking stage. Storage stability of wholemeal flour, white flour, bran and germ of wheat were also investigated. Storage at 20°C for 12 mo decreased vitamin E activity of the various wheat fractions by 28-40%.     

Changes in chemical composition and antioxidative properties of rye ginger cakes during their shelf-life

Changes in chemical composition and antioxidative properties of rye ginger cakes during their shelf-life were investigated in this study. In particular, the changes in antioxidants content, antioxidative and reducing capacity, and Maillard reaction development in rye ginger cakes after long-term storage were addressed. Ginger cakes produced according to the traditional and current recipe were stored for 5 years at room temperature in a dark place. The total phenolic compounds (TPC), inositol hexaphosphate (IP6), reduced (GSH) and oxidised glutathione (GSSG) contents, antioxidant and reducing capacity and Maillard reaction products (MRPs) were determined in ginger cakes after storage and then compared to those measured after baking. After long-term storage a decrease in TPC and IP6 contents in cakes was noted. In contrast, an increase in antioxidative and reducing capacity of stored cakes was observed. Long-term storage induced formation of furosine, advanced and final Maillard reaction products and caused changes in both reduced and oxidised forms of glutathione. After long-term storage the modest changes in furosine, FAST index and browning in ginger cake formulated with dark rye flour may suggest that this product is the healthiest among others. Therefore, traditional rye ginger cakes can be considered as an example of a healthy food that is also relatively stable during long term storage as noted by the small chemical changes observed in its composition.     

Effect of Flour Extraction Rate and Baking on Thiamine and Riboflavin Content and Antioxidant Capacity of Traditional Rye Bread

ABSTRACT:  The effect of rye flour extraction rates and baking on thiamine and riboflavin content, and antioxidant capacity of traditional rye bread were studied and compared with white wheat flour. The content of thiamine was higher (10.9%) in rye dough formulated with dark rye flour (F-100%; extraction rate of 100%) than in rye dough formulated with brown rye flour (F-92%; extraction rate of 92%) that was similar to dough made with wheat flour. The riboflavin content in rye dough made from flour F-100% was also higher (16%) than in dough formulated with flour F-92%, and both provided larger riboflavin content than wheat dough. Baking led to reductions in thiamine of 56% for wheat bread and of 20% for both rye breads; however, this process caused only a 10% decrease in riboflavin for wheat bread and a 30% decrease for rye breads. Trolox equivalent antioxidant capacity, peroxyl radical scavenging capacity, DPPH radical scavenging activity, and Folin–Ciocalteu reducing capacity were higher in rye than in wheat dough and bread. Baking process produced slight changes in antioxidant activity, except for Superoxide Dismutase-like activity where a sharp decrease was observed. Our findings showed that rye breads are an important source of B vitamins and rye breads formulated with dark and brown flours showed better antioxidant properties than wheat bread. Therefore, rye breads should be more widely recommended in human nutrition.     

Evaluation of bioprocesses to improve the antioxidant properties of chickpeas

Chickpea seeds (Cicer arietinum cv. Blanco lechoso) were submitted to different bioprocesses; i) germination of seeds for 2 and 3 days, ii) natural fermentation of flour or cracked seeds, and iii) induced fermentation of flour or cracked seeds with Lactobacillus plantarum, in order to improve the antioxidant properties. Determination of vitamins C and E, reduced glutathione (GSH) and total phenolic compounds (TPC) were carried out. Antioxidant capacity was measured by SOD-like activity, peroxyl radical-trapping capacity (PRTC), lipid peroxidation inhibition (LPI) and trolox equivalent antioxidant capacity (TEAC). Vitamin C and E increased after germination, whilst fermentation caused a decrease in vitamin E. Both bioprocesses caused an increment in TPC content while GSH decreased. Germination increased SOD-like activity (47-41%), PRTC (16-55%) and TEAC (12-23%) and a slight inhibition of LPI was observed. After fermentation, SOD-like activity suffer a drastic reduction. The LPI decreased between 11.3 and 21.3%, while an increase of TEAC (29-57%) and PRTC (27-44%) was observed, except in flour natural fermented seeds where decreased the PRTC. TPC contributed highly to total antioxidant capacity (TEAC). Results indicated that with the bioprocesses studied the antioxidant properties of chickpea flours are enhanced and they can be used as desired ingredients for new functional food formulations.     

Protein profile and sensorial properties of rye breads

The protein profile of four types of traditional rye breads formed on rye flours with the extraction rate of 100, 95, 85 and 70% and baked at 260 °C for 40 min was investigated as a nutritional quality indicator. A fractionation process was applied to discriminate high-molecular- (HMW >3 kDa) and low-molecular weight compounds (LMW <3 kDa) present in extracts of rye bread and its crumb and crust. The content of soluble proteins, available lysine, carbohydrates and total phenolic compounds was analysed before and after ultrafiltration in both retentates (HMW >3 kDa) and filtrates (LMW <3 kDa). The dependence between sensory quality of rye breads and composition on soluble proteins, available lysine, carbohydrates and total phenolic compounds was provided. Baking caused a decrease in rye bread protein content. The content of available lysine was the lowest in crusts and it was dependent on the rye flour extraction rate taken for rye bread making. The SDS-PAGE analysis showed that the primary structure of the rye bread proteins was modified in the highest extent in the crust’s bread of all types. The analyses of both retentates and filtrates after ultrafiltration demonstrated that the most of carbohydrates and phenolic compounds were incorporated into the HMW fraction suggesting their conjugation with proteins due to the Maillard reaction. Compounds able to react with Folin Ciocalteu reagent were also detected in filtrates of crust’s extracts (MW ≤3 kDa) from all breads indicating their distribution between LMW and HMW fractions. About 22.5, 27, 11.2 and 46.8% of the phenol compounds forming crusts of breads based on the flours with extraction rates of 100, 95, 85 and 70% were recovered in the corresponding LMW fractions.The sensory analysis of the four types of rye breads indicated for a high correlation between overall quality of breads and their content of carbohydrates. The highest correlation was noted for a rye bread formed on flour with extraction rate of 95%. This finding suggested that the content of carbohydrates as a substrate for Maillard reaction has had an influence on palatability by consumers of rye bread formed on flour with the extraction rate of 95% which had also the highest overall quality.     

Investigation of product quality, sensory profile and ultrastructure of breads made from a range of commercial gluten-free flours compared to their wheat counterparts

Bread is a major staple food consumed daily in all parts of the world. A significant part of the human population cannot tolerate gluten, a storage protein found in wheat, rye and barley, and therefore, products made from alternative cereals are required. During this study, the bread-making potential of seven gluten-free flours, wheat and wholemeal wheat flour was compared. Fermentation potential of the different flours was determined, showing that dough development height of gluten-free and wholemeal wheat samples was lower than for wheat and oat flour. Apart from standard bread quality parameters such as loaf-specific volume and physical crumb texture, also water activity and shelf life have been determined. The shelf life of gluten-free breads was reduced compared to wheat bread. Aroma profiles were evaluated by a trained panel. Wheat, oat and wholemeal wheat breads were liked moderately, while the remaining samples had lower liking scores. Crumb grain characteristics were investigated using image analysis, and microstructure was observed by scanning electron microscopy. Overall, only breads produced from oat flour were of similar quality to wheat bread, and the utilization of buckwheat, rice, maize, quinoa, sorghum and teff flours resulted in breads of inferior quality.     

Supercritical Fluid Extraction of Bioactive Compounds: Fundamentals,Applications and Economic Perspectives

This review provides an updated overview of the most important applications of supercritical fluids in the extraction of bioactive compounds from plant matrices. The main factors influencing the extraction yields, solubility, and manufacturing costs are described. Aspects concerning the operational processing in the extraction and fractionation are also discussed. The data compiled herein are focused on the extraction of essential oils, phenolic compounds, carotenoids, tocopherols, and tocotrienols.     

Comparative analysis of techno-functional properties,starch digestion and protein quality of pigmented chickpea flours

The aims of this investigation were to evaluate physicochemical, functional, pasting, and thermal properties, as well as the starch and protein digestibilities of whole flours obtained from ten chickpea cultivars differing in seed coat colour (black, brown, green, red and cream). The coloured chickpeas flours contained higher amounts of bioactive compounds as total phenolics (TPC, 241.25–444.41 μg gallic acid equivalents per g), β-glucans (1.02–2.42 g/100 g), resistant starch (22.68–37.52% of total starch) and higher protein digestibility corrected amino acid scores (PDCAAS, 0.61–0.82) compared with the cream-coloured chickpea Blanco Sinaloa (C.BS). The principal component analysis showed several differences among the chemical compositions, starch digestions and seed protein qualities; in the same sense we found a correlation between TPC and starch content with their thermal properties and starch digestion. Subsequently, pigmented chickpea cultivars have potential as functional ingredients for food product development.     

Development and application of analytical methods for the determination of mycotoxins in organic and conventional wheat.

The aim of this study was to develop a multicomponent analytical method for the determination of deoxynivalenol (DON), ochratoxin A (OTA) and zearalenone (ZEN), nivalenol (NIV), 3-acetyl-DON (3-acDON), 15-acetyl-DON (15-acDON), zearalenol (ZOL) and citrinin (CIT) in wheat. It also aimed to survey the presence and amounts of DON, OTA and ZEN in Belgian conventionally and organically produced wheat grain and in wholemeal wheat flours. After solvent extraction, an anion-exchange column (SAX) was used to fix the acidic mycotoxins (OTA, CIT), whilst the neutral mycotoxins flowing through the SAX column were further purified by filtration on a MycoSep cartridge. OTA and CIT were then analysed by high-performance liquid chromatography (HPLC) using an isocratic flow and fluorescence detection, while the neutral mycotoxins were separated by a linear gradient and detected by double-mode (ultraviolet light fluorescence) detection. The average DON, ZEN and OTA recovery rates from spiked blank wheat flour were 92, 83 and 73% (RSDR = 12, 10 and 9%), respectively. Moreover, this method offered the respective detection limits of 50, 1.5 and 0.05 microg kg-1 and good agreement with reference methods and inter-laboratory comparison exercises. Organic and conventional wheat samples harvested in 2002 and 2003 in Belgium were analysed for DON, OTA and ZEN, while wholemeal wheat flour samples were taken from Belgian retail shops and analysed for OTA and DON. Conventional wheat tended to be more frequently contaminated with DON and ZEN than organic samples, the difference being more significant for ZEN in samples harvested in 2002. The mean OTA, DON and ZEA concentrations were 0.067, 675 and 75 microg kg-1 in conventional samples against 0.063, 285 and 19 microg kg-1 in organically produced wheat in 2002, respectively. Wheat samples collected in 2003 were less affected by DON and ZEN than the 2002 harvest. Organic wholemeal wheat flours were more frequently contaminated by OTA than conventional samples (p < 0.10). The opposite pattern was shown for DON, organic samples being more frequently contaminated than conventional flours (p < 0.10).     

Detection of wheat gliadins in heated food by reversed-phase high-pressure liquid chromatography

To recognize and determine the wheat gliadins in unheated gluten-free food for coeliac patients the immunological methods such as ELISA can be used. In heated food (above 80 degrees-90 degrees C) these methods fail wholly or in part to achieve the quantitative determination of wheat gliadin. The changes in protein patterns after heat treatment are also revealed by the RP-HPLC of wheat gliadins and some peaks appear, which are characteristic for heat treated wheat flour. Using these peaks, about 2% admixture of wheat flour (T. aestivum, T. durum) as well as of rye flour can be detected. In foods which contain more than 50% skim milk the addition of only at least 5% of these flours can be detected. The ethanolic extracts of foods were concentrated by freeze-drying prior to analysis by HPLC. The ethanol-soluble non-dialysable food components affect the quantitative determination of wheat or rye proteins by means of peak areas. Selective enrichment is a possibility. The RP-HPLC-analysis of ethanol-soluble proteins makes it possible to detect heated flours of wheat and rye (cooked, roller-dried, extrusion-cooked) in glutenfree food.     

Preparation of β-glucan and antioxidant-rich fractions by stone milling of hull-less barley

Stone milling of hull-less barley in combination with size-based separation of the milled fractions was used for preparation of flours with different compositions of macronutrients and bioactive compounds. According to similar compositions, specific milled fractions were combined to define three flours. The flour with the largest mass fraction (~70%) comprised particle sizes < 124 μm, which showed lower fibre, residual ash and antioxidant contents than the unfractionated flour. The flour with particles from 124 to 250 μm (~20% mass fraction) had >twofold greater β-glucan content, and the flour with particles > 250 μm (~10% mass fraction) had >threefold greater content of antioxidants than unfractionated flour. Each of these three flour fractions represents valuable material that can be incorporated into bakery products to enhance functional and health-related properties. Large enrichment factors of bioactive compounds in barley flours can be obtained using small-scale and widely available milling equipment.     

Amino Acid Profiles of Fermenting Wheat Sour Doughs

The free amino acid patterns of unfermented and fermented wheat sour doughs started with Lactobacillus plantarum were related by factor analysis to dough yield, ash content of flour, fermentation temperature and presence/absence of yeast, from data corresponding to a central composite design of samples. Individual levels of hydrophobic, acid and basic amino acids as well as total amino acid content positively correlated with extraction rate of flours. The presence of yeast promoted metabolism of histidine, aspartic acid and asparagine, particularly in samples made with whole and wholemeal flours. Proliferation of predominant amino acids by enzymatic release was more notable at higher fermentation temperatures and wholemeal samples. Sour doughs with maximum levels of hydrophobic and basic amino acids were started with no yeast bacterial cultures, made with whole and wholemeal flours and fermented at 35°C.     

The application of dextran compared to other hydrocolloids as a novel food ingredient to compensate for low protein in biscuit and wholemeal wheat flour

Wheat is primarily used for bread-making. However, fungal diseases, grain moisture at harvest and low-protein contents strongly influence the quality of the wheat flour, thus creating challenges for traders, millers and commercial bakers who struggle to produce consistently high-quality products. This paper address the replacement of low-protein/wholemeal flour functionality for bread-making purposes. Three hydrocolloids, xanthan gum, dextran and hydroxypropyl methylcellulose, were incorporated into bread recipes based on high-protein flours, low-protein flours and coarse wholemeal flour. Hydrocolloid levels of 0–5 % (flour basis) were used in bread recipes to test the water absorption. The quality parameters of dough (farinograph, extensograph, rheofermentometre) and bread (specific volume, crumb structure and staling profile) were determined. Results showed that xanthan had negative impact on the dough and bread quality characteristics. HPMC and dextran generally improved dough and bread quality and showed dosage dependence. Volume of low-protein flour breads were significantly improved by incorporation of 0.5 % of the latter two hydrocolloids. However, dextran outperformed HPMC regarding initial bread hardness and staling shelf life regardless the flour applied in the formulation.     

Antioxidant capacity and polyphenolic content of high-protein lupin products

In order to produce high protein lupin products, α-galactoside extraction from Lupinus angustifolius cv. Troll and cv. Emir and Lupinus albus cv. Multolupa, and protein isolation from L. albus cv. Multolupa were carried out. Trolox equivalent antioxidant capacity (TEAC), DPPH radical-scavenging activity (DPPH-RSA), peroxyl radical-trapping capacity (PRTC), superoxide dismutase-like activity (SOD-like activity), total phenolic compounds (TPC) and total flavonoids were determined in lupin products. In L. angustifolius cv. Troll, L. angustifolius cv. Emir and L. albus cv. Multolupa α-galactoside-low flours, the TEAC and DPPH-RSA decreased (43%, 38%; 73%, 82%; 77%, 38%, respectively). PRTC decreased in L. angustifolius cv. Troll and L. albus cv. Multolupa α-galactoside-low flours (13% and 98%, respectively), while in those of L. angustifolius cv. Emir, PRTC increased (25%). SOD-like activity and TPC were also affected by α-galactoside extraction and reductions of 30–52% and 38–56%, respectively, were observed. The protein isolate of L. albus cv. Multolupa presented lower TEAC (24%), a similar level of PRTC and twice higher level of DPPH-RSA than did α-galactoside-low Multolupa flour. Moreover, the SOD-like activity of lupin protein isolate was sharply reduced but the TPC content was 24% higher. The technological procedures, α-galactoside extraction and protein isolation, provide high protein lupin products but with lower antioxidant capacity and total phenolic compounds than the raw seeds, although the levels of antioxidant capacity of these lupin products resemble those of cereals.     

Comparative study of colorectal health related compounds in different types of bread: Analysis of bread samples pre and post digestion in a batch fermentation model of the human intestine

Seven different types of wheat and rye bread were analysed for colorectal health related compounds, pre and post digestion, in batch fermentation model of the human intestine. Pre digestion, higher amounts of colorectal health-related dietary fibre compounds (soluble/insoluble/total dietary fibre, arabinoxylans, β-glucans) and phytochemicals (mono-/di-phenolic acids, phytic acid, hydroxymethylfurfural) were detected in wholemeal than in refined flour types of bread, as well as in rye flour types than in wheat flour types of bread. Post digestion, faecal bacterial metabolites of colorectal health promoting (acetate/propionate/butyrate, lactate, free mono-/di-phenolic acids) and impairing (amino metabolites, bile acid metabolites) activities were found in fermentation supernatants of bread samples. All types of bread positively affected faecal bacterial metabolism; among the different types of bread, the highest stimulation of organic acid production (acetate/propionate/butyrate, lactate) and the lowest detrimental bacterial enzyme activities (β-glucuronidase, urease) were detected for wheat flour bread, whereas the strongest retardation of bacterial bile acid degradation and the strongest stimulation of phenolic acid metabolite release (phenylpropionic/phenylpropenoic acid derivatives) were induced by wholemeal rye bread. This study for the first time presents a qualitative and quantitative overview over the broad spectrum of colorectal health related compounds in high- and low-fibre types of bread, pre and post in vitro digestion, and highlights the significance of bread for the preventive nutritional intervention of colorectal cancer.     

Bioactive compounds in the cereal grains before and after hydrothermal processing

The studies aimed at explaining the role of cereals as the source of biologically active compounds. Wheat (Triticum aestivum L.) cv. Almari, barley (Hordeum vulgare L.) cv. Gregor, rye (Secale cereale L.) cv. Dankowskie Zlote and oat (Avena sativa L.) cv. Slawko were used in the study. The content of the following biologically active compounds was determined: inositol phosphates, tocopherols, tocotrienols, reduced glutathione, melatonin, phenolic acids as well as the content of microelements (Cu, Zn, Mn and Se). The behaviour of these compounds under extrusion cooking (process temperatures of 120–160–200°), which was taken as a model of hydrothermal processes, was analyzed. Extrusion caused a significant decrease in all the compounds tested, except for phenolic ones. A decrease in inositol hexaphosphate, depending on the species of cereal, was from 4 to 50%, in tocopherols and tocotrienols, from 63 to 94%, in reduced glutathione, from 20 to 50%, and in melatonin, from 17 to 63%. An increase in the content of phenolic acids (free and released from ester bonds) reached from 200 to 300%.