Study on the interactions between soy and semolina proteins during pasta making

Spaghetti produced in a pilot plant were made from semolina and semolina blended with 10%, 15%, 25% or 50% of defatted soy flour (DSF) or toasted soy flour (TSF).Proteins of spaghetti were characterized by size exclusion-high-performance liquid chromatography (SE-HPLC). Results showed that soy globulins interact with semolina proteins during pasta making, forming polymers of high molecular weight. Of these, the sodium dodecyl sulphate-unextractable components were significantly higher (p < 0.001) (up to 49% unextractable polymeric proteins) (UPP) than that of spaghetti made of semolina (24.6% UPP). The decrease of S–S bonds and the increase of –SH free groups in the DSF–semolina spaghetti, with respect to that made of only semolina, suggest that polymerization among the different classes of proteins involves interaction by sulphydryl residues in blends with above 15% of DSF and that soy proteins tend to disrupt own gluten S–S interchange system. In the TSF–semolina spaghetti the increase of S–S bonds was higher with respect to that of –SH free, suggesting that the heat treatment, to which the TSF proteins were subjected, allowed them to cross link to semolina proteins by disulphide bonds.     

Changes in durum wheat kernel and pasta proteins induced by toasting and drying processes

Durum wheat kernels were subjected to a toasting process and the proteins characterised by size exclusion-high performance liquid chromatography (SE-HPLC) and sodium dodecyl sulphate–polyacrylamide gel electrophoresis. With this physical process, albumins and globulins, as well as glutenins and gliadins, polymerised as seen by a shift of the SE-HPLC profile to lower elution times. The polymerisation seemed to happen mainly through disulphide bonds, even though the participation of ω-gliadins to the aggregation suggested the involvement of other kinds of interactions. It led to the revelation of a new peak originated by thermal aggregation of small polymeric proteins. The changes in the chromatographic profile were accompanied by increasing amounts of total unextractable polymeric proteins. The replacement of semolina with toasted durum wheat flour (5%, 10%, 15%, 20% and 30%) for the production of pasta in the shape of spaghetti significantly (p < 0.001) affected the molecular size distribution of the polymeric proteins, even though the replacement of semolina with 5% and 10% of toasted durum wheat flour (TDWF) did not significantly (p > 0.05) change the unextractable polymeric proteins (UPP) when compared with spaghetti made with 100% durum semolina. On the other hand, the replacements of semolina with 15–30% TDWF showed significant (p < 0.001) increase in UPP when compared with 100% durum semolina spaghetti.     

Cooking behaviour and acceptability of composite pasta made of semolina and toasted or partially defatted soy flour

The effects of the replacement of increasing amounts of semolina with toasted or partially defatted soy flour on dough rheological indices and spaghetti quality were evaluated. The replacement caused the dough weakening and the increase of the tenacity-extensibility ratio. Due to the competition of soy proteins and starch for water, the substitution of increasing amounts of semolina was able to increase the optimal cooking time without significant changes of the ratio between the increase in weight or diameter and the weight or diameter of dry spaghetti (ΔP/P and ΔD/D) but with a significant slowing of the ΔL/L (ratio between the increase in length and the length of dry spaghetti) increase during overcooking. Around the optimal cooking time, the release of organic matter was higher in pasta made exclusively of semolina whereas the sensory response was similar for control and composite spaghetti. Statistically significant correlations were obtained between protein content of the flour mixtures or dough alveographic indices and the cooking behaviour of semolina-soy spaghetti according to non-linear regression models. In particular, both protein content and alveographic indices allowed to predict approximately 92-94% of the variation of cooking losses and, in a lower measure, the variation of bulkiness and elasticity of semolina-soy spaghetti.     

Effect of the Addition of Common Bean (Phaseolus vulgaris L.) Flour on the In Vitro Digestibility of Starch and Undigestible Carbohydrates in Spaghetti

Abstract: Spaghetti is considered to be a slowly digestible starch food, a feature ruled by the particular physical properties of the product. Several studies have been reported to increase nutritional value of spaghetti, using legumes. We have studied the addition of common bean flour on the starch in vitro digestibility. Spaghetti was prepared with semolina and different concentrations of common bean flour (0%, 15%, 30%, and 45%, w/w). Proximate analysis, optimal cooking time, and cooking loss were estimated in crude spaghetti. Total, available, and resistant starches, indigestible fractions, and in vitro starch hydrolysis kinetics were accomplished in cooked spaghetti. Pasta with 30% and 45% of common bean flour showed higher values of protein. Particularly, the lowest cooking time was observed for composite spaghetti with 45% of common bean flour. There was a significant increase in cooking loss when common bean flour in the composite was added. Composite spaghetti samples with increasing common bean flour showed decreasing values of total starch but an important increase in the resistant starch (RS) level and indigestible insoluble fraction values. Plain pasta made with semolina showed the highest enzymatic hydrolysis rate, which decreased when common bean flour was added to the spaghetti. Spaghetti with a higher level of common bean flour was more slowly available, which may have positive implications for human health.     

Effect of semolina and absorption level on extrusion of spaghetti containing non‐traditional ingredients

Specific mechanical energy (SME), mechanical energy, extrusion rate and temperature of extruded spaghetti were monitored to determine the effects of semolina, hydration level and non‐traditional ingredients on pasta extrusion using a semi‐commercial pasta press with a fixed screw speed of 25 rpm. SME transferred to the dough during extrusion and the temperature of extruded spaghetti were greater with strong than with weak gluten semolina and at low than at high absorption levels. When compared with semolina hydrated to 300 g kg^?1 absorption, SME transferred to the dough was 13 kJ kg^?1 lower for semolina mixed with buckwheat (Fagopyrum esculentum Moench.) bran flour, 47 kJ kg^?1 lower for semolina mixed with flaxseed (Linum usitativissimum L.) flour and 7 kJ kg^?1 lower for semolina mixed with wheat (Triticum turgidum var. durum L.) bran. Weak gluten semolina, high absorption levels and non‐traditional ingredients reduced the mechanical energy required for extrusion more than they reduced extrusion rate. The target temperature for extruded spaghetti was 45 °C. The temperature of extruded spaghetti containing flaxseed flour was below 45 °C whereas the temperature of spaghetti containing wheat bran was above 45 °C, regardless of semolina type or absorption level. Copyright © 2006 Society of Chemical Industry     

Spaghetti cooking quality of waxy and non‐waxy durum wheats and blends

Quality attributes of waxy durum wheat (Triticum turgidum L), milled semolina and cooked spaghetti were examined and compared with those of two non‐waxy durum cultivars. With the exception of kernel hardness, wheat quality characteristics were similar for both waxy and non‐waxy durum. Compared with average values obtained for durum wheat grown in North Dakota (USA) during the crop year 2000, the values obtained for the wheat used in this study were equal or better for most parameters evaluated. Semolina extraction for all samples was lower than the 2000 average of 62.6%. The waxy lines had higher ash, lower speck count, similar protein quantity, lower wet gluten and stronger mixograph curves than the non‐waxy cultivars. Waxy durum semolina had higher lipid content, starch damage, stirring number and flour swelling values. Spaghetti made from waxy durum semolina had shorter cooking time, similar cooking loss and cooked weight and lower firmness values, which would be unacceptable by most standards. Spaghetti made from blends containing 20–80% waxy durum semolina were evaluated. Cooking time and firmness decreased and cooking loss increased as the amount of waxy semolina increased. Acceptable spaghetti was obtained using 20–40% waxy semolina blends, depending on the quality of the non‐waxy blending material. Copyright © 2004 Society of Chemical Industry     

Native and modified chayotextle flour effect on functional property and cooking quality of spaghetti

The objective of this research was to study the effect of partially substituting semolina flour by native (NCHF) and modified chayotextle (CHFMD) flours, on the physicochemical properties and cooking quality of spaghetti. Spaghetti was obtained by replacing semolina flour (control) with five different concentrations of NCHF and CHFMD flours (10%, 17.5%, 25%, 32.5% and 40%). The proximal composition of the flours showed that both NCHF and CHFMD flours lower content of protein and fat but higher content of ash and resistant starch (RS). Moreover, the RS content increased due to thermal modification (TM) and that RS remained high, even after the cooking process. Pasting properties such as peak viscosity, breakdown, setback and final viscosity were influenced by NCHF and CHFMD concentrations. Brightness (ΔL^*) was significantly reduced by inclusion of increasing CHFMD levels. True density and water absorption values increased with addition of NCHF and CHFMD, compared to the control spaghetti. The results obtained in this study demonstrated the possibility for producing spaghetti containing up to 40% CHFMD flour, with acceptable quality and functional properties.     

Effect of microbial transglutaminase on spaghetti quality

ABSTRACT:  To examine the potential application of microbial transglutaminase (MTG) on semolina dough properties and quality of raw and cooked spaghetti, the effects of various MTG addition levels on the solubility of proteins, SDS-PAGE pattern of semolina dough proteins, and textural and structural properties of raw and cooked spaghetti were investigated using semolina from a high-protein good variety (MACS 1967) and a low-protein poor variety (PDW 274) durum wheat. To increase the concentration of lysyl residues and possibly enhance the extent of cross-linking of protein matrix by MTG, a commercial soy protein isolate (SPI) was added at a level of 3% (w/w) in combination with MTG, and its effect on semolina dough properties and spaghetti quality was investigated. The addition of MTG significantly decreased the solubility of semolina dough proteins. SDS-PAGE results showed that with increasing levels of MTG, a progressive decrease in the intensity of the bands corresponding to molecular weight of around 66 kDa was observed. Protein cross-linking reaction catalyzed by MTG resulted in changes in dough properties, dry spaghetti quality, cooking quality characteristics, and microstructure of cooked spaghetti. However, the quality improvements were more evident in spaghetti from the poor variety PDW 274 than from the good variety MACS 1967. The results also showed the ability of MTG in the formation of heterologous polymers between SPI and durum wheat proteins to improve the quality of spaghetti samples.     

Role of gluten and its components in influencing durum wheat dough properties and spaghetti cooking quality

Protein is an important component of grain which affects the technological properties of durum wheat. It is known that the amount and composition of protein can influence dough rheology and pasta quality but the influence of the major classes of protein is not well documented. The influence of the various gluten components on dough and pasta properties was investigated. The protein composition of durum semolina was altered by either adding gluten fractions to a base semolina or preparing reconstituted flours with varying protein composition. The effects on semolina dough rheology and spaghetti texture were measured. Published methods to isolate relatively pure quantities (gram amounts) of glutenin, gliadin, high molecular and low molecular weight glutenin subunits were evaluated and modified procedures were adopted. Reconstituted flours with additional glutenin increased dough strength while additional gliadin and LMW‐GS decreased strength. These changes did not impact on spaghetti texture. Results from using the addition of protein fractions to a base semolina showed that gluten and glutenin addition increased the dough strength of a weak base semolina while gliadin addition weakened the base dough further. Addition of HMW‐GS greatly increased dough strength of the base while addition of LMW‐GS greatly reduced dough strength. Again, these affects were not translated into firmer pasta. Copyright © 2007 Society of Chemical Industry     

Fortification of pasta with split pea and faba bean flours: Pasta processing and quality evaluation

Nutritionally enhanced spaghetti was produced by adding high amounts (35% db) of legume flour (split pea or faba bean) to durum wheat semolina. The production of fortified pasta required an adaptation of the pasta making process (higher hydration level and mixing speed) to limit agglomeration of particles during mixing. Moreover, addition of legume flour induced a decrease in some pasta quality attributes (e.g. higher cooking loss, lower breaking energy). This could be attributed to the introduction of non-gluten proteins and insoluble fibres which weakened the overall structure of pasta. A modification of the sensorial properties including higher hardness and higher fracturability were also observed. Some quality attributes (e.g. lower cooking loss) of fortified pasta were improved by applying high and very high temperatures during the drying cycle, reflecting strengthening of the protein network. However, these treatments resulted in excessively firm and rubbery pasta according to the panelists.     

Microbial loads, mycotoxins, and quality of durum wheat from the 2001 harvest of the northern plains region of the United States

The 2001 durum wheat crop grown in the Northern Plains was surveyed for microbial loads, mycotoxins, and quality. Correlations among these factors were identified. Effects of cleaning, milling, and pasta processing on microbial loads and deoxynivalenol (DON) concentrations were determined. Aerobic plate counts (APCs), mold and yeast counts (MYCs), internal mold infection (IMI), and internal Fusarium infection (IFI) were lowest in grain samples from Montana and highest in grain from northeastern North Dakota. DON and 15-acetyldeoxynivalenol (15-ADON) were not detected in samples from Montana. Nivalenol was not detected in any samples. DON in North Dakota samples ranged from none detected to 23 micrograms/g. 15-ADON was detected in a few North Dakota samples, with a maximum of 0.8 microgram/g. DON positively correlated with APCs, MYCs, IFI, damaged kernels, total defects, U.S. grade number, and tombstone kernel content and negatively correlated with test weight, vitreous kernel content, and kernel weight. APCs, MYCs, and DON concentrations were lower in semolina than whole grain. Processing semolina into spaghetti did not change DON concentrations. APCs for spaghetti were reduced 2.2 to 4.1 logs from those for semolina, whereas MYCs were reduced 0.1 to 1.7 log. Some APCs in durum flour and semolina were higher than certain industry specifications would allow, although other factors were acceptable. However, microbial loads in the spaghetti were all within specifications found in the available literature.     

Pasta with Unripe Banana Flour: Physical, Texture, and Preference Study

ABSTRACT:  Banana is a starchy food that contains a high proportion of undigestible compounds such as resistant starch and nonstarch polysaccharides. Products with low glycemic response such as pasta are considered favorable to health. The objective of this study was to use unripe banana flour to make spaghetti with low-carbohydrates digestibility and evaluate its physical and texture characteristics, as well as consumer preference. Formulations with 100% durum wheat semolina (control) and formulations with 3 semolina: banana flour ratios (85: 15, 70: 30, and 55: 45) were prepared for spaghetti processing. The use of banana flour decreased the lightness and diameter of cooked spaghetti, and increased the water absorption of the product. Hardness and elasticity of spaghetti were not affected by banana flour, but adhesiveness and chewiness increased as the banana flour level in the blend rose. Spaghettis prepared in the laboratory (control and those with banana flour) did not show differences in preference by consumers. In general, the preference of spaghettis with different banana flour level was similar. The addition of a source of undigestible carbohydrates (banana flour) to spaghetti is possible without affecting the consumer preference.     

Phenolic profile and carbohydrate digestibility of durum spaghetti enriched with buckwheat flour and bran

The potential of common buckwheat flour (Supreme) and bran (Farinetta) in improving upon the phenolic and antioxidant properties of durum spaghetti was investigated. The cooking quality and carbohydrate digestibility of products were also studied. Significantly large increments of between 114 and 522% for total phenolic content (TPC), 50 and 242% for total flavonoids content (TFC), and over 359% for 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity were recorded for uncooked experimental spaghetti samples over the control. Farinetta contributed more phenolic and antioxidant compounds than Supreme flour. Processing and cooking resulted in decreases in phenolic content and antioxidant activity. Cooking losses of up to 8.8% were recorded for the experimental samples and were higher in Farinetta-substituted products. These were generally higher than that of the control (6.3%). The introduction of buckwheat increased carbohydrate digestibility of products, but at the same time, resulted in an overall lower amount of reducing sugars after 120 min of in vitro hydrolysis. Results show that the phenolic and antioxidant properties of durum spaghetti fortified with buckwheat milling fractions can compare favourably with those of 100% whole buckwheat soba pasta, and at the same time, maintain a higher cooking quality due to the presence of semolina.     

Effect of two barley β-glucan concentrates on in vitro glycaemic impact and cooking quality of spaghetti

The in vitro glycaemic impact and cooking quality of functional spaghetti made with semolina plus the addition of one of either two types β-glucan barley concentrates, Glucagel^® (GG) and Barley Balance™ (BB) was investigated. For each β-glucan type, five spaghetti samples containing different percentages of β-glucan (2, 4, 6, 8 and 10 g/100 g) were developed and compared to a control (0 g/100 g of β-glucan). The glycaemic potency of the samples was measured in vitro as the release of glucose during pancreatic digestion. Further tests were carried out on the spaghetti samples to determine optimal cooking time (OCT), cooking losses (CL), dry matter, swelling index, colour, hardness and adhesiveness. Barley Balance, but not GG, significantly reduced the susceptibility of spaghetti to pancreatic digestion in vitro compared to the control at all concentrations. Results indicated moreover that the spaghetti added with GG and BB (all the treatments) did not have different colour and hardness properties compared to spaghetti without β-glucan. Except for the spaghetti with 2 g/100 g BB, all the other treatments demonstrated significantly higher CL and adhesiveness values compared to the control.Cooking losses (CL) and adhesiveness are important parameters and they were significantly different for samples with added barley β-glucan concentrates. BB appears to be a better treatment for reducing the glycaemic potency of spaghetti and justifies further in vivo study.     

小麦粉品质和制面工艺对面条品质的影响研究

以普通小麦为原料，以非传统细条实心面条为对象，研究了挤压温度，食盐含量及小麦粉品质对细细条实心面成品品质的影响。结果认为，升高加工温度，可以降低挤压阻力：提高食盐含量，增加挤压阻力。提高温度和食盐含量，都能增加面条的蒸吸水率和蒸煮干物质失落率。温度对面条蒸煮蛋白质的损失率影响较大。样品的蛋白质品质和淀粉的糊化特性对品质也有较大的影响。     

A study of the relationship between the mechanical properties and the sensorial optimal cooking time of spaghetti

This study investigated the relationship between the mechanical properties and the sensorial optimal cooking time (OCT) of spaghetti. Three semolina spaghetti samples with an increasing radius and three non-conventional spaghetti samples (one wholemeal semolina and two maize-based spaghetti) were analyzed. Tenacity, elongation at break and phase shift angle (tan delta) were monitored during the cooking and overcooking of spaghetti using a dynamic mechanical analyzer. The sensorial OCT was also determined by a trained panel. Results highlight that the mechanical parameters are related with the OCT for all investigated spaghetti samples. In particular, a relationship was observed with elongation at break and tan delta.     

Use of a toasted durum whole meal in the production of a traditional Italian pasta: chemical, mechanical, sensory and image analyses

The characterisation of traditional Italian pasta obtained by mixing amounts of toasted whole meal with re-milled semolina and other ingredients was obtained by means of physico-chemical, rheological, mechanical, sensory and image analyses. The toasted meal showed higher ash, fibre and protein contents than re-milled semolina. The replacement of percentages of re-milled semolina with the toasted meal and soft flour increased tenacity and decreased extensibility and strength, making the dough less suitable for pasta-making. The P / L values were indices of high starch damage. The replacement of part of re-milled semolina and water with toasted whole wheat meal, soft flour and eggs increased the optimal cooking time and the amount of water absorbed during cooking but made the other cooking parameters worse. The image analysis provided evidence of the changes induced by the use of toasted wholemeal, soft flour and eggs in the microscopic structure of pasta protein and starch.     

Technological properties and non-enzymatic browning of white lupin protein enriched spaghetti

Spaghetti was prepared by replacing semolina with different amounts of lupin protein, in order to increase the protein content. A detailed investigation of the rheological properties of the dough and the cooking quality of pasta was performed in comparison to standard semolina spaghetti. Moreover, the effect of the addition of lupin protein on non-enzymatic browning was evaluated by measuring ε-furoylmethyllysine (furosine) and 5-hydroxymethyl-2-furancarboxaldehyde (HMF), which are considered useful indices of semolina quality and pasta processing conditions. Dried spaghetti fortified with 5% of lupin protein isolate has a colour and rheological features comparable with the semolina sample and also the behaviour during cooking results to be satisfactory. As far as the thermal damage is concerned, the furosine values of fortified spaghetti differ only marginally from standard pasta and the percentage lysine loss is quite small (ranging from 12.1% to 15.7%).     

Quality of spaghetti pasta containing Mexican common bean flour (Phaseolus vulgaris L.)

The objective of this research was to study the effect of the addition of common bean flour to semolina on the cooking quality and total phenolic content of pasta. Pasta was obtained at three temperatures (60, 70 and 80 °C) and two levels of added common bean flour (15% and 30%); plain pasta (100% semolina) was used as control. Moisture, optimal cooking time, cooking loss, water absorption capacity, colour change, firmness and total phenolic and furosine contents were measured. The cooking time and water absorption were diminished in spaghetti pasta with added common bean flour; cooking loss increased and firmness decreased as a function of the bean flour percentage. A linear relationship between colour change and common bean flour content in pasta was found. Increases of furosine and phenolic contents in pasta with the addition of bean flour were observed.