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To determine the lycopene content of extruded products containing 10% tomato skin, the conditions for solvent extraction were optimised. After three extraction cycles at 50 °C each for 15 min at a solvent to meal ratio of 40:1, a maximum of 6.6 ppm lycopene was extracted. However, the extraction was considered incomplete, thus the product was digested by pancreatin prior to extraction. The extracted lycopene content was increased to 23.5 ppm using the optimum conditions of 20 min of digestion with 10 mg mL−1 pancreatin. To validate the extraction efficiency at optimum conditions, a set of extruded products containing different lycopene concentrations was used. Digestion increased the extracted lycopene content by more than 2.5-fold between the products. Furthermore, this inclusion significantly improved the correlation coefficient between the red colour and the extracted lycopene content. Therefore, including a digestion step prior to extraction by solvents was necessary to efficiently extract lycopene from extruded products.

The present study investigates the effects of incorporating buckwheat flour (BW) into Chinese steamed bread (CSB). Different levels (0, 5, 10, and 15 %) of BW were added into wheat flour. The physical quality of dough was measured as moisture and textural properties of the dough. Quality of CSB was analyzed from two perspectives: physical properties and nutritional quality. For physical properties, specific volume, loaf height, moisture, and texture were measured by AACC methods. The nutritional quality of the bread was analyzed using the glycemic response determined by an in vitro digestion method. The results illustrate that the incorporation of BW into wheat flour reduces the extensibility of the dough, decreases specific volume, increases bread hardness, gumminess, and chewiness. However, this study also shows that addition of BW can decrease the glycemic response of steamed bread by up to 23 %. This study illustrates the potential addition of buckwheat flour to improve the nutritional quality of CSB.

Adding tomato derivatives to traditional starchy extruded snacks can improve their nutritional properties by adding lycopene and fibre; however the physico-chemical properties of these products must also be considered. Ingredients and extrusion parameters, including temperature, alter these properties, but their effect on lycopene content is not known. In this study, crisp low density extruded snacks were manufactured from corn, wheat and rice, with or without dried tomato skin or paste powder extruded at temperatures of 140, 160 or 180 °C. Lycopene content and the physico-chemical properties (expansion, density, hardness, colour parameters and percentage of moisture loss) of the extruded products were measured. Lycopene retention was higher in products containing tomato skin powder and significantly lower when wheat flour was used to make the snacks. Increases in the processing temperature improved the physico-chemical characteristics of the snacks but had no significant effect on lycopene retention ( P > 0.05).

Summary Iron deficiency is one of the most common nutritional deficiencies worldwide, in both developing and developed regions. Although the aetiology of iron deficiency and resultant anaemia may be multifaceted, inadequate iron intakes, poor iron absorption and disease status may all be underlying causes. Whilst nutrition and supplement interventions may go some way towards improving iron status in ‘at-risk’ populations, their efficacy can be questioned. New approaches, including food-based strategies, may be an alternative means of improving the iron status and health of the public sectors. Economically, food-based approaches may also be more cost-effective than iron supplements. This paper aims to discuss how the food industry may play an important role in improving the iron status of public sectors, helping to prevent iron deficiency and need for tablet-based iron supplements.

The formation of SCFA and the digestion of rice fibre using the following probiotics (Lactobacillus rhamnosus, Lactobacillus acidophilus, Bifidobacterium longum, Bifidobacterium breve) was compared using total dietary fibre (TDF), insoluble dietary fibre (IDF) and soluble dietary fibre (SDF) from two varieties (milling grades) of rice. The milling grade of the rice had no significant effect (P SDF > IDF for all the probiotics tested and major difference between the species was the time to form the SCFA. The pattern of SCFA formation from both rice fibre fractions was acetate > propionate > butyrate for all the organisms with no significant difference between the micro-organisms (P 0.05).

Summary A study was conducted to assess the effects of rice dietary fibre on the fermentative activity of human faecal microflora. Dietary fibre was extracted from four commercially available Sri Lankan rice varieties [LD 356, AT 353 (red in colour); BG 352, and BG 358 (white in colour)], and separated into individual fractions of total dietary fibre (TDF), insoluble dietary fibre (IDF) and soluble dietary fibre (SDF). Four healthy human subjects were given a diet containing the four rice varieties for more than 4 months prior to the study. Faecal microflora was obtained from human volunteers, after the 4 months of rice based diet, and used for anaerobic fermentation of the individual rice fibres. Short Chain Fatty Acid (SCFA) production was analysed at 0, 2, 4, 6 and 24 h by gas liquid chromatography. Among the SCFA, acetate was the most abundant acid formed in all rice varieties. The fibre fractions from rice variety LD 356 (TDF16.73%, SDF 3.57%, 11.9% IDF) gave the highest yield of SCFA while the variety BG 358 gave the least. Total dietary fibre of all rice varieties contributed to produce more SCFA than the individual soluble dietary fibre and insoluble dietary fibre fractions.

A range of commercially available dietary fibres (DFs), representing both insoluble and soluble forms, were used in the production of pasta. Addition of fibre was at a range of levels (2.5-10%). The potential glycaemic index of these pastas was then evaluated using an in vitro model system to determine starch digestibility and sugar release. Scanning electron microscopy was used to relate structural properties of the pasta to starch degradation. The resulting predicted glycaemic indexes illustrated that the inclusion of DFs into pasta can reduce the glycaemic index of an already low GI food by up to 40%. As such, compared to the predicted glycaemic index value for the control fresh pasta (GI = 45), inclusion of pea fibre, guar gum and locust bean gum yielded pasta with GI values of 39.2, 37.9 and 37 respectively. Thus the type of dietary fibre used was important in the rate of starch digestion observed during the in vitro process. Equally, the level of fibre inclusion was of importance with an inclusion rate of 2.5% generally resulting in pasta with a predictive GI of 42.1, whereas an inclusion of 10% yielded pasta with a GI value of 37.2. Such reductions could be achieved through a number of possible mechanisms including antagonistic and synergistic relationships existing between DF's and other food components, the effect of DF's in entrapping pasta particles and thus inhibiting starch degradation, and the restriction of water movement during the cooking of pasta products, thus indicating that starch swelling is impaired.

Summary Numerous in vitro carbohydrate digestion methods exist for analysis of the likely glycaemic properties of foods. Generally these methods encompass simulations of oral, gastric and intestinal digestion processes, but the way in which physiological conditions are implemented across methods differs considerably. Some differences are in the mode of comminution, inclusion and duration of a gastric digestion, and choice of amylolytic enzyme. Incubation temperature, pH, duration and stirring mode also differ between methods. Such differences, particularly the method used to mimic chewing, can have a substantial influence on the relative estimate of glycaemic potency for a given food. To achieve estimates of high predictive power, and global relevance, a validated, standardised in vitro digestion method must be developed. This article provides a systematic review of commonly used and referred to in vitro carbohydrate digestion methods. Methodological discrepancies between protocols are identified thus defining the route a systematic standardisation investigation should take.

The extraction of nonstarch polysaccharides from fruits and vegetables has received much attention recently in terms of their utilisation in functional food systems. In New Zealand kiwifruit production is one of the major fruit growing exploits. This paper explores the potential extraction techniques which may be employed to extract water soluble polysaccharides from kiwifruit material, in an attempt to utilise this commodity as an added value food ingredient. Crude water soluble polysaccharides of fresh gold kiwifruit were extracted under different extraction techniques (acid, hot water and enzyme) and conditions (time, temperature and concentration). The recovery of water soluble polysaccharide fraction (WSP), chemical composition, and their rheological behaviour were examined. The extraction technique had a significant effect on the WSP yield, galacturonic acid content, as well as the viscosity. Enzymatic extraction method yielded higher WSP and galacturonic acid than water and acid extraction, but this fraction exhibited lower viscosity. Acid extracted WSP yield decreased with increasing temperature and time. In contrast, water extracted WSP yield increased with increasing temperature and time. The selected extraction parameters for acid extraction were temperature 50 °C, extraction time 60 min, and 1:6 kiwifruit puree to acid solution ratio. The water extraction optimum parameters were 25 °C, 30 min and 1:4 puree to water ratio and 25 °C, 30 min with medium concentration for enzymatic extraction. The WSP viscosity and galacturonic acid content was maximum under these extraction conditions.

A range of three commercial starch ingredients (differing in amylose/ amylopectin ratios) were incorporated into a processed cheese formulation. The use of starch in the cheese system significantly increased the cook (final) viscosity of the cheese mixture compared to the control formulation. Starch containing high amounts of amylose produced hot cheese pastes with the highest final viscosity values. Processed cheese firmness was significantly increased with starch addition. Cheese products with high-amylose starch recorded a five-fold increase in firmness, whereas high amylopectin-based starches yielded a two-fold increase in firmness. No significant differences were observed in the adhesive and cohesive properties of the processed cheeses when starch was added to the formulation. The addition of starch to the cheese samples significantly reduced the degree of melt of the processed cheese samples compared to the control. The high-amylose starch exhibited a minimum of a 26% reduction in the degree of melt compared to the control sample. The amount of cheese melt decreased with increased starch content.

Summary Barley beta-glucan, partially hydrolysed guar gum and inulin were used in the processing of low-fat yoghurts. The possible beneficial effects of carbohydrate fat replacers on the rheological, textural and sensory quality of low-fat yoghurt-based products were determined. Comparisons were made between the sample yoghurts made from a low-fat milk base, and full-fat and low-fat yoghurt controls. The inclusion of the carbohydrate components reduced product syneresis and improved the texture and rheological properties of the low-fat-based products so that their quality characteristics were similar to yoghurt made with full-fat milk. Both the type and also the amount of carbohydrate component altered product characteristics. Beta-glucan addition at low level (0.5%) was effective in improving serum retention of the yoghurt and its viscoelastic nature (G′, G′ and tan δ). In contrast, higher levels (above 2%) of inulin and guar gum were needed to exert significant improvements in the textural characteristics of yoghurt. Sensory analysis conducted on the samples illustrated that the inclusion of carbohydrate-based fat replacers could be successfully utilised to mimic full-fat products.

Two non-starch polysaccharides, guar gum and wheat bran, were used at 15% replacement level in a cereal base to produce an extruded breakfast cereal product from both wholemeal and high-ratio wheat flour mixes. The inclusion of the non-starch polysaccharides into the flour bases had no significant effect on the expansion ratio of the products. However, the product density and bulk density of the extruded products increased with guar gum and wheat bran addition. The pasting properties of the raw flour and polysaccharide base as well as the extruded products were altered with the incorporation of polysaccharides, with guar gum-enriched products showing elevated peak and final viscosity readings. This appeared to be related to moisture manipulation and hence the regulation of gelatinisation. In vitro starch hydrolysis of the raw bases and the extruded samples illustrated that the extrusion process significantly increased the availability of carbohydrates for digestion. Additionally, the inclusion of non-starch polysaccharides in the raw bases significantly reduced the rate and extent of carbohydrate hydrolysis. This potentially glycaemic reducing action was also evident in the extruded products where the incorporation of guar gum at 15% yielded a reduction of starch hydrolysis of 36% in the wholemeal base and 32% in the high-ratio white wheat flour base.

Summary Sweet potato (kumara) tubers of differing colours (orange, red and white) were used to produce tuber flour, a purified starch fraction and an isolated fibre extract. The fractions from each tuber colour were added into a biscuit mixture, and the effects of tuber source and fraction composition were observed in relation to the physico-chemical characteristics of biscuits. Addition of sweet potato flour and fibre fractions to white wheat flour significantly reduced the pasting properties (peak and final viscosity) of the resulting gels by up to seven-fold compared with the control wheat flour gel (as determined by the Rapid Visco Analyser). The addition of sweet potato starch affected the pasting properties of wheat flour–sweet potato starch mixes to a lesser extent. Biscuit texture (force required to cause a biscuit to fracture) was significantly reduced with the incorporation of sweet potato fibre into the biscuit dough preparation, this was linked to a reduction in biscuit thickness and spread ratio. However, the addition of sweet potato flour and starch resulted in biscuits of similar firmness as the control biscuits.

Non-starch polysaccharides (NSPs) and celite (used as inert filler) were incorporated into wheat flour and wheat starch paste preparations at levels of 1, 2.5, and 5% in both addition and replacement modes. Pasting properties of gums were compared using a Rapid Visco Analyser. Use of guar gum and locust bean gum elevated the peak and final viscosities of the resulting pastes (when used in either addition or replacement modes), whereas arabic gum significantly reduced the peak and final viscosity properties of the pastes. Samples which comprised wheat starch yielded higher peak and final viscosity characteristics compared to wheat flour containing samples, however higher breakdown and setback values were observed for samples using wheat flour as a base compared to wheat starch. The firmness of the gels (as determined using a texture analyser) increased with the use of wheat starch compared to wheat flour. Little significant difference was observed between NSP used and mode of application (replacement or addition). In vitro starch degradation was conducted on the wheat flour gels. Guar gum and locust bean gum reduced the amount of starch degradation in these gels, whereas arabic gum and celite increased the amount of starch hydrolysis (or were similar to the control). The rate of starch hydrolysis appears to be related to the viscosity altering behaviour of the NSPs in a starch-rich system. The results indicate that selection of NSPs is important as gum arabic has the potential to increase starch hydrolysis compared to the control.

Nonstarch polysaccharides (NSPs), both soluble and insoluble, were added to pasta doughs at levels of 2.5%, 5%, 7.5%, and 10% levels. The cooking and textural characteristics of the pastas were evaluated using a range of analytical techniques. Generally, NSP addition was found to increase the cooking losses, and reduce the protein and starch contents of the pasta. This effect was dependent on the level of NSP added and also the type (soluble or insoluble). Pasta firmness was generally reduced in relation to the level of NSP addition, although some gel-forming NSPs resulted in higher firmness values. Pasta stickiness, adhesiveness, and elasticity were also affected. The results indicate that careful selection of NSP addition is needed to ensure optimum textural and cooking characteristics in NSP enriched pasta products.

Traditional white bread is a poor source of dietary fibre, containing typically less than 2.5%. A demand exists for the development of high fibre white breads of nutritional benefit to the consumer. This paper explores the possibility of using Glucagel ® , a β-glucan isolate, from barley ( Hordeum vulgare ) to raise the nutritional status of bread products. Glucagel ® was incorporated into breads at 2.5 and 5% inclusion rates. Negative changes were observed in dough quality and baking performance with the addition of Glucagel ® . In vitro analysis of the bread samples revealed a significant decrease in reducing sugar release over a 300 m digestion in breads supplemented with 5% Glucagelsample. However, incorporation of Glucagelincrease starch availability for digestion. This has implications in the reduction of hyperglycaemia and hyperinsulinaemia, with reference to the control of diabetes and development of degenerative diseases.

The behaviour and susceptibility to degradation of a high molecular weight (HMW) and low molecular weight (LMW) barley β-glucan in white bread during manufacture and in vitro digestion were investigated. The incorporation of both HMW and LMW barley β-glucan resulted in stiffer dough, lowered loaf volume and height compared to the control. The HMW barley β-glucan caused the greatest loss of dough and bread quality. Breads with HMW and LMW barley β-glucan exhibited attenuated reducing sugars release (RSR) over a 300 min in vitro digestion compared to the control, with generally no difference between the breads. HMW barley β-glucan was degraded during bread manufacture; however, degradation of the LMW barley β-glucan was not apparent. An in vitro digestion did not result in any further degradation of the molecular weight (MW) of either barley β-glucan.

Gold kiwifruit pomace extracted using citric acid, water and enzyme (Celluclast 1.5L) were studied in terms of pectin yield, protein, ash, non-starch polysaccharide, galacturonic acid (GalA), neutral sugar composition, molar mass (Mw), viscosity and degree of branching. Water-extracted pectin was considered closest to its native form. Enzyme extracted pectin showed the highest yield (∼ 4.5%w/w) as compared with the acid and water extraction methods (∼ 3.6-3.8%w/w). Pectin obtained from different extraction methods showed different degree of branching. The Mw and root mean square (RMS) radius varied with the extraction methods with values of 8.4 × 10(5) g/mol and 92 nm, 8.5 × 10(5)g/mol and 102 nm, 6.7 × 10(5) g/mol and 52 nm for acid, water and enzymatic extraction methods, respectively. Similar trend was observed for pectin viscosity, with water-extracted pectin giving a slightly higher viscosity followed by acid and enzyme-extracted pectin. This study showed that gold kiwifruit pomace pectin has potential application in food products.

Summary Some physical and chemical characteristics of nine Syrian durum wheat genotypes were determined in order to investigate the relationships among individual kernel components and kernel quality. All genotypes were grown on fully irrigated plots in Syria. Test weight, 1000-kernel weight, kernel size distribution, hardness and semolina extraction rates were determined along with the chemical characteristics of the kernel (ash, moisture, protein, wet gluten, starch content and falling number). All tested genotypes had high test weight (83.1–85.9 kg hl−1) and 1000-kernel weight (42.5–55.5 g) indicating high milling yield potential. Additionally, all the wheat genotypes demonstrated high falling numbers (433–597 s). Correlation coefficients among the quality properties showed that moisture content did not demonstrate any strong correlations with the studied quality parameters. Protein content exhibited a positive correlation with vitreousness (r = 0.78), and a negative correlation with ash content (r = −0.57). Test weight exhibited a negative correlation with 1000-kernel weight (r = −0.66), and a positive correlation was observed between test weight and starch content of the kernel (r = 0.78). The results illustrate the commonality between Syrian durum wheat genotypes and US and Canadian durum wheat genotypes reported by researchers previously.

Summary Kernel quality characteristics, semolina milling potential, dough rheology and pasta making properties of kernels from nine fully irrigated Syrian durum wheat genotypes were observed. Protein content of the kernels exerted a significant affect on the physical characteristics hardness and the degree of kernel vitreousness, both of which were highly correlated with superior end-use product. Gluten composition of semolina appeared as significant as overall protein content in determining the optimum end-use product cooking quality (cooking time and pasta texture). The final viscosity of durum flour exhibited positive correlations with semolina recovery, protein content, gluten content, vitreousness, the optimum-cooking time of pasta and pasta firmness. This indicates the relevance of using the rapid visco analyser technique in evaluating the durum wheat and pasta qualities. Dough rheology measurements confirmed that farinograph and extensograph are useful indicators of the cooking properties of pasta. The research also illustrates that although variability between Syrian durum wheat genotypes were observed, their milling and processing parameters were similar to those previously reported for Canadian and American durum wheats, indicating the potential to use these lines in mainstream pasta production.

The influence of fenugreek material on starch and flour rheological characteristics was determined. Ground fenugreek grain material, and a purified fenugreek extract (Fenulife®) were used as replacement or as addition to flour or starch. Evaluation of the pasting properties of starch and flour fenugreek mixtures illustrated that fenugreek addition increased the peak and final viscosity of the mixtures in relation to the level of fenugreek addition used. The ground fenugreek seeds yielded a lower response than the purified Fenulife® sample, due to the presence of protein, starch and other polysaccharide material in the ground flour. Rheology of the pastes showed that the addition of fenugreek material (especially Fenulife®) increased the viscoelastic nature of the material. Textural analysis of the cooled gels illustrated that the inclusion of fenugreek into flour mixes generally raised the hardness of the gels, although the gels became softer with higher levels of fenugreek material used. The inclusion of fenugreek into starch gels showed similar patterns of pasting and textural properties, with a general decrease in texture related to the level of fenugreek included.

Summary The effect of the addition of a β-glucan fibre fraction from barley to durum wheat pasta was evaluated in terms of cooking characteristics, structure, texture and in vitro starch digestibility. Barley β-glucan (BBG) fibre fraction was incorporated into pasta at 2.5%, 5%, 7.5% and 10% inclusion rates. Incorporation of the BBG fibre fraction to pasta attenuated reducing sugar release during in vitro digestion, the magnitude of reduction being related to the level of BBG fibre fraction inclusion. Changes to pasta cooking quality and texture were observed with BBG fibre fraction addition, including greater solid loss during cooking, increased pasta swelling and loss of hardness compared with the control pasta. Investigation of pasta microstructure and characterisation of starch gelatinisation events indicated that a combination of changes to the starch–protein matrix and the high water binding capacity of β-glucan alters the physico-chemical properties and digestibility of the pastas.

ARSTRACT: Cereal β-glucan is regarded as a soluble dietary fiber, which has potential nutritional benefits within the food industry. This article explore the possibility of using a β-glucan rich fraction (BGF) extract from barley (Hordeum vulgare) in bread products. BGF was incorporated into bread mixes at 2.5% and 5% incusion rates. Analysis of the pasting characteristics of BGF and wheat flour mixes revealed a decrease in peak and final viscosity related to the level of BGF addition. Dough extendibility increased with addition of 5% BGF compared with the control, probably because of the weak gel-forming capability of β-glucan, creating an elastic dough. However, loaf volume and height decreased with the addition of BGF, Analysis of the bread samples Illustrated that 5% BGF inclusion resulted in a significant decrease in the release of reducing sugars over a 300-min digestion, compared with the control bread sample. The results showed a potential for the use of low levels of β-glucan to improve the nutritional quulity of bread products.

Slaughter blood haem was encapsulated in lecithin : cholesterol Liposomes. Wheat flour was fortified with this mixture at two levels (60 and 100 mg/100 g flour) using the haem liposomes as iron source. The effect of haem fortification on gluten and fat content of flours was determined, as were the effects of fortification on dough visco-elastic characteristics (water absorption, development time, dough stability and breakdown time). The baking properties of the breads were also investigated. The addition of haem liposomes increased the fat content of flours, and had a positive effect on the stability and rheological characteristics of the dough. Loaf volume and crumb uniformity was improved. These results indicate a potential nutritional use for haem liposomes.

The health-related importance of dietary fibre, as part of a balanced diet, has been recognised for decades. More recently, soluble fibre such as (1→3,1→4)-β- d -glucan (referred to as β-glucan), has been shown to have effects on the glycaemic, insulin, and cholesterol responses to foods. Cereals (such as barley and oats) are good sources for these functional ingredients, with studies clearly demonstrating their potential nutritional benefits. At the same time research has indicated that the efficacy of β-glucans may be related to extraction procedures, and factors such as dose, molecular weight and fine structure, and rheological characteristics of extracted and native β-glucans. Concurrently, research has focussed on the inclusion of β-glucans into both cereal and dairy-based food systems, illustrating their potential as ingredients to manipulate food structure and texture. Thus, β-glucans (from barley, oat, and other cereals) should be regarded as important functional ingredients for the cereal foods industry.

The much publicised global trend in rising levels of obesity and diabetes has refuelled interest in the dietary intake of the macronutrients (fat, protein, and carbohydrates) necessary to maintain the state of normalcy (good health) of an individual. Both scientific and public attention have focused on the dietary mediation of chronic health syndromes, either through use of dietary supplements, or a review of the whole diet situation. Dietary supplements have been used extensively both as pharmacological supplements, food ingredients, in processed foods to aid weight control, and the regulation of glucose control for diabetic patients. Particular interest has focused on the use of dietary fibres, especially soluble dietary fibres (such as guar gum, locust bean gum, and psyllium fibres), resistant starch, and slowly digestible carbohydrates. These have been shown to alter food structure, texture, and viscosity, and hence the rate of starch degradation during digestion. Research has also illustrated an association between the rate of carbohydrate degradation during digestion, and the regulation of postprandial blood sugar and insulin levels. The current paper explores the potential use of dietary fibres in the treatment of obesity and diabetes.

The effects of dietary fiber inclusion on biscuit texture, cooking properties, and sugar release after in vitro degradation were investigated. Inulin, β-glucan enriched fraction (BGEF), potato fiber, and a resistant starch were used. Effects of the dietary fibers on the pasting properties of flour based mixtures were investigated using a rapid visco analyzer. Results showed a reduction in visco-pasting properties (peak viscosity and final viscosity) of the flour–dietary fiber systems with increasing fiber content. Addition of dietary fiber into the biscuits affected biscuit shrinkage and height development during cooking, as well as generally reducing the resistance of biscuits to snapping during texture analysis tests. Sugar release during in vitro degradation studies showed a highly significant decline when comparing dietary fiber enriched biscuits to the control samples. This would have a beneficial effect in potentially reducing the glycaemic index and subsequent glycaemic loading of such foods.

Summary The pasting properties, gelatinization profiles and freeze–thaw stability of natural waxy maize starches, pasted in the presence of xanthan gum (XG) and resistant starch, were evaluated using a Rapid Visco Analyser, together with turbidimetric analysis. Freeze–thaw stability was determined for four cycles over a 4 weeks period. The final viscosity of the pastes was unaffected by the addition of resistant starch (RS) whereas XG additions increased final viscosity. Addition of mixtures of combinations of XG and RS increased the peak viscosity of the starch pastes. Freeze–thaw stability (as estimated by the final viscosity of the pastes during a series of four freeze–thaw cycles) was improved with the addition of XG.

The beneficial role of dietary fibre in human nutrition has lead to a growing demand for incorporation of novel fibres, particularly barley β-glucans, into foods. Barley β-glucans are regarded as dietary fibre ingredients that are partially soluble in water. The aim of the present work was to investigate the possibility of using barley β-glucan in milk systems in relation to the coagulation properties of milk containing β-glucan, and to the rheology, texture and microstructure of fresh curds. The rate of coagulation and optimum coagulum cutting time were evaluated using rheological measurements. Results show that coagulation/gelation time of the milk can be reduced significantly with the incorporation of β-glucan; curd yield increased and the viscoelastic properties of the curd were altered with β-glucan additions. The relationships between curd rheological behaviour and its microstructure are discussed in relation to use of novel hydrocolloids in dairy processing. The results suggest that barley β-glucan has the potential to be used as a fat replacer in low-fat dairy systems. Copyright © 2004 Society of Chemical Industry

The effects of inulin addition on the cooking properties, texture and nutritional characteristics of durum wheat pasta were determined. Inulin was shown to influence the swelling index and firmness, but not the adhesiveness and elasticity of pasta products. Addition of inulin to pasta also had a nutritional advantage, showing a slower release of sugars during in vitro starch digestion, and thus reducing the predicted glycaemic index by up to fifteen per cent. The results suggest that by using non-starch polysaccharides it is possible to enhance the nutritional quality of pasta, without deleteriously affecting its cooking and textural properties.

ABSTΡACT: We evaluated the effects of estraction treatment on the yield and composition of β-glucan-rich fiber fractions from barley, and the subsequent influence of these traction on the thermal properties and pasting behavior of starch pastes. Estraction treatment affected the yield of barley β-glucan (EBG) fiber fraction, and β-glucan recovery efficiency (P < 0.005). The level of inclusion of these frection in starch water allspersions bad a significant =influence on the pasting characteristics such as peak viscosity (PV), breakdown (BI)), and final viseosity (FV) development (as determined using a Rapid Visco Analyser), Substitution of 5% wheat starch with the fiber fractions decreased PV, HD, and FV in comparison to the control starch (P < 0.05). Substitution of 5% wheat starch with BBG fiber fraction resulted in a decrease in enthalpy (J/g) values compared with the control (P < 0.05). A reduction in pasting characteristics may be associated with a reduced enthalpy of starch galatinlzation and retentiln of the integrity of the starch granale. The reduction in PV may also indicate a reduced degree of starch grande swelling.

Feta cheese was produced commercially with different caprine to ovine milk ratios. Milk fat concentrations, moisture and salt contents were similar for all the batches. However, the hardness and adhesive characteristics of the cheeses differed in relation to the milk ratio. The hardness of the cheese appeared to be correlated to increased goat milk content. Cryo-scanning electron microscopy (cryo-SEM) of the cheese samples showed that feta cheese with a higher proportion of caprine milk had a more compact and less porous appearance than feta produced from purely ovine milk. This difference in cheese structure helps to explain the difference in hardness between the samples.

The physiochemical composition of durum wheat cultivars was studied in order to investigate the influence of vitreousness on the chemical composition of starch and its thermal and pasting properties. Six durum wheat lines were chosen and grown in northern Syria. Grains of each cultivar were visually sorted according to the degree of vitreousness into fully vitreous and fully starchy fractions. Amylose/amylopectin ratio and total starch was determined using Megazyme methods, while thermal and pasting properties were determined using DSC and RVA. Starchy kernels were higher in total starch than vitreous kernels but showed a decreased amylose content. Negative linear relations were found between amylose content, and both peak viscosity and breakdown. Trends in variation of gelatinisation characteristics were observed between vitreous and starchy kernels from the same cultivar, with higher total enthalpy being associated with starchy grains compared with vitreous grains of the same line.

With the increase in consumer and processor attention in the functionality of foods, there is a need for a deeper understanding behind how the composition of food affects its nutritional quality. Of particular interest is the role of non-starch polysaccharides and slowly digestible carbohydrates in the possible regulation of starch degradation from carbohydrate rich foods, thus reducing the overall glycaemic impact of such products. The review discusses some of the more recent research findings with regards to food production and nutrition.

Research was conducted to examine the effect of inulin on the rheological and textural characteristics of yog-ice cream desserts in relation to their sensory attributes. Addition of inulin to yog-ice cream was shown to increase viscosity of the yogurt-ice cream mix and increase hardness of the resulting yog-ice cream. Meltdown characteristics of the yog-ice creams demonstrated a clear relationship between increased oligosaccharide levels and improved melting properties. L'inuline, glucide non digestible contenant des fructo-oligosides, possede des proprietes metaboliques interessantes. Cette etude evalue l'effet de l'inuline sur les caracteristiques rheologiques et texturales de cremes glacees au yaourt en relation avec leurs attributs sensoriels. L'addition d'inuline augmente la viscosite du melange et la durete de la creme glacee. Les resultats montrent une relation claire entre l'augmentation des teneurs en oligosides et l'amelioration des proprietes de fusion.

Marine-based food supplements can improve human nutrition. In an effort to modulate glycaemic response and enhance nutritional aspects, marine-derived algal food rich in astaxanthin was used in the formulation of a model food (wholemeal cookie). Astaxanthin substitution of cookies made from three flours (wheat, barley and oat) demonstrated a significant reduction in the rate of glucose released during in vitro digestion together with an increase in the total phenolic content (TPC) and antioxidant capacity of the food. The significantly (p < 0.005) lower free glucose release was observed from cookies with 15% astaxanthin, followed by 10% and then 5% astaxanthin in comparison with control cookies of each flour. Total phenolic content, DPPH radical scavenging and Oxygen Radical Absorbance Capacity (ORAC) value also notably increased with increase in astaxanthin content. The results evidence the potential use of microalgae to enhance the bioactive compounds and lower the glycaemic response of wholemeal flour cookie.

Sweet corn is one of the most widely planted crops in China. Sprouting of grains is a new processes to increase the nutritional value of grain products. The present study explores the effects of light on the nutritional quality of sweet corn sprouts. Gene expression of phenolic biosynthesis, phytochemical profiles and antioxidant activity were studied. Two treatments (light and dark) were selected and the morphological structure of sweet corn sprouts, as well as their biochemical composition were investigated to determine the effects of light on the regulation of genes responsible for nutritional compounds. Transcription analyses for three key-encoding genes in the biosynthesis of the precursors of phenolic were studied. Results revealed a negative regulation in the expression of ZmPAL with total phenolic content (TPC) in the light group. TPC and total flavonoid content (TFC) increased during germination and this was correlated with an increase in antioxidant activity (r = 0.95 and 1.0). The findings illustrate that the nutritional value of sweet corn for the consumer can be improved through germination to the euphylla stage.

Studies on gold kiwifruit pectins are limited. In this work, the characterization of pectin isolated from two different stages of maturity of gold kiwifruit, namely early harvested fruit (EHF) and main harvested fruit (MHF) isolated by three methods (acid, water, enzymatic) was carried out. Pectins isolated from MHF were higher in galacturonic acid content (52–59% w/w) and weight-average molecular weights ( M w , 1.7–3.8 × 10 6 g/mol) compared with EHF pectins (29–49% w/w and 0.2–1.7 × 10 6 g/mol respectively). Enzymatic treatment gave the highest yield but lowest in M w , viscosity and mechanical spectra for both maturities. The pectin of both maturities was classified as high-methoxyl pectin with the degree of esterification ranged from 82% to 90%. Water-extracted MHF pectin molecules had the highest RMS radius (182.7 nm) and M w (3.75 × 10 6 g/mol). The water extraction method appeared to retain the native state of pectin molecules compared with acid and enzymatic extraction methods based on the M w and viscosity data.

The relationship between pasta texture and physicostructural characteristics was determined in relation to potential starch degradation and subsequent glucose release. Pastas with added soluble and insoluble dietary fiber ingredients were evaluated in relation to biochemical composition, cooking properties, and textural characteristics. Results show that both the type and amount of added fiber influence the overall quality of both raw and cooked pasta. Glucose release may be significantly reduced by the addition of soluble dietary fiber.

The two biopolymers protein and starch are used to enhance the textural properties of food and play a key role in the formulation of novel food structures. In this paper, the interactions between dairy proteins and starch are discussed with a focus on the recent development on the rheological, pasting, and microstructural properties of these systems. Fortification of extruded cereal based snacks with dairy proteins leads to nutritious and energy dense snack foods. Milk proteins and starch interactions, and their effects on physiochemical and functional properties of extruded products are also explored in this review. Processing parameters of the extrusion process and feed characteristics affect final product quality and act as an important contributor in the determination of overall product texture. Fortification with dairy proteins may result in an acceptable quality of extrusion based ready to eat (RTE) snack foods. This review article will help food technologists to design and predict a product's behaviour during processing and final texture of a starch–protein based food system.

Six pairs of near isogenic lines, differing in the presence of absence of D hordein, were produced in backgrounds with different B and C hordein alleles by introducing a Hor 3 null gene discovered in a barley germplasm collection. Biochemical and cytochemical studies were performed on the harvested and malted grains. Statistical comparisons of the composition of the grains and their malting performance revealed that neither presence or absence of D hordein, nor gel protein levels related to differences in malting performance of the different lines. However, differences in hordein amount and in the grain ultrastructural characteristics could be related to some differences in malting performance between and within some pairs of lines.