Effects of Different Drying Conditions on Water Absorption and Gelatinization Properties of Pasta

Three flat pasta types dried by low temperature (LT), high temperature (HT), and very high temperature (VHT) drying profiles were analyzed. The starch properties of these pastas, cooked at different temperatures for different times, were investigated. The starch properties were examined by observing starch swelling with a scanning electron microscope (SEM), identifying the phase difference with an ultrasonic device, and determining the water absorption and gelatinization rate with the BAP method and X-ray diffraction. The SEM images revealed expanded and gelatinized starch granules during cooking pasta and increased with drying temperature. The water absorption of pasta increased with cooking temperatures and times, and the trend was LT > HT > VHT-dried pasta. The gelatinization rate of pasta increased with cooking time and temperature. The X-ray diffractograms of pasta cooked less than 12 min showed typical A-type X-ray diffraction patterns, while in pasta cooked for 12 min, V-type diffraction was observed. Uncooked pasta showed an enhanced peak at about 2θ?=?20°, which indicated the generation of high levels of amylose–lipid complexes. The present study found that these changes occurred during drying and may affect pasta starch characteristics.     

Effect of Sorghum Flour Addition on In Vitro Starch Digestibility,Cooking Quality,and Consumer Acceptability of Durum Wheat Pasta

Whole grain sorghum is a valuable source of resistant starch and polyphenolic antioxidants and its addition into staple food like pasta may reduce the starch digestibility. However, incorporating nondurum wheat materials into pasta provides a challenge in terms of maintaining cooking quality and consumer acceptability. Pasta was prepared from 100% durum wheat semolina (DWS) as control or by replacing DWS with either wholegrain red sorghum flour (RSF) or white sorghum flour (WSF) each at 20%, 30%, and 40% incorporation levels, following a laboratory‐scale procedure. Pasta samples were evaluated for proximate composition, in vitro starch digestibility, cooking quality, and consumer acceptability. The addition of both RSF and WSF lowered the extent of in vitro starch digestion at all substitution levels compared to the control pasta. The rapidly digestible starch was lowered in all the sorghum‐containing pastas compared to the control pasta. Neither RSF or WSF addition affected the pasta quality attributes (water absorption, swelling index, dry matter, adhesiveness, cohesiveness, and springiness), except color and hardness which were negatively affected. Consumer sensory results indicated that pasta samples containing 20% and 30% RSF or WSF had acceptable palatability based on meeting one or both of the preset acceptability criteria. It is concluded that the addition of wholegrain sorghum flour to pasta at 30% incorporation level is possible to reduce starch digestibility, while maintaining adequate cooking quality and consumer acceptability.     

Effect of Processing on the Physico-Chemical Characteristics of Quinoa Flour (Chenopodium quinoa,Willd)

The nature and extent of the modification of starch in quinoa, caused by various processes like cooking and autoclaving of the seeds, drum drying of the flour and extrusion of the grits was investigated by measuring the physico-chemical properties - the water absorption, water solubility, swelling power, viscosity and degree of gelatinisation - of the processed samples. Autoclaved samples showed the lowest degree of gelatinisation (32.5% by DSC) of the starch, while the degree of gelatinisation of the precooked/drum dried samples was found to be 97.4% by DSC method. Higher polymer degradation was observed in cooked samples than in autoclaved samples as seen in the gel chromatographic separation. The water solubility in cooked samples (5.44 to 15.58) and in autoclaved samples (7.02 to 9.64) increased with the process time. In the extrusion process, the moisture content as well as the compression ratio was found to affect the degree of starch modification significantly (p <0.01).     

A Meta‐Analysis of Enriched Pasta: What Are the Effects of Enrichment and Process Specifications on the Quality Attributes of Pasta?

Pasta products enriched with ingredients to improve their nutritional value or functionality have become increasingly popular, and substantial research efforts have been directed towards the development of new enriched pasta products. In this work, a meta‐analysis was conducted to quantify the impact of enrichment and process specifications on the quality attributes of pasta. A literature search revealed 66 studies on enriched pasta. Process specifications and quality attributes, namely proximate composition, dough, drying, cooking, and mechanical properties, color, and sensory attributes, were extracted from the studies and compiled in a data set. Analysis of the data set revealed significant differences between pasta enriched with high‐fiber ingredients and pasta enriched with pulse flour. High‐fiber ingredients generally preserved the quality attributes of pasta more effectively than pulse flour. Comparisons based on the drying temperature showed that high drying temperatures generally improve the cooking properties of enriched pasta. Sensory evaluations indicated that enrichment levels below 10% generally do not affect consumer acceptance, but higher enrichment levels significantly decrease it. Pearson correlation coefficients showed that the gelatinization temperature and Farinograph properties are useful indicators of the mechanical properties and sensory attributes of pasta. The meta‐analysis revealed the need to better understand the impact of the processing history of the enrichment ingredient on the quality attributes and the health benefits of enriched pasta.     

Gluten-free pasta production from banana and cassava flours with egg white protein and soy protein addition

Egg white protein and soy protein were incorporated into a banana and cassava flour blend (75:25) to produce gluten-free pasta. The objectives of study were to investigate the effects of the different protein sources on the physico-chemical properties of gluten-free pasta. The levels of protein inclusion were 0%, 5%, 10% and 15% of composite flour (w/w) for each type of protein. Pasta made from 100% durum wheat semolina was used as controls. The protein fortification affected the total starch, resistant starch and protein content of gluten-free pasta compared to semolina pasta. No significant effects of soy/egg white protein addition were found in either insoluble or soluble dietary fibre content. Cooking properties of pasta (optimum cooking time, swelling index, water adsorption index and cooking loss) and texture properties (firmness and extensibility) were affected by the level of protein addition and the type of protein. Results showed the utilisation of 25% cassava flour and protein inclusion have a promising application in gluten-free pasta production.     

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.     

Effects of Applied Process on the In Vitro Digestibility and Resistant Starch Content of Pasta Products

Resistant starch (RS) included in pasta can have auspicious health benefits and functional properties. The resistance of starch, however, can be greatly influenced by the applied food preparation process. The aim of the present study was to investigate the effects of two different resistant starches on the digestibility of pasta and to predict the impact of the conventional pasta processing (extrusion under standard conditions, 120 bars, 40°C; drying in an air-drying room at 35–40°C and cooking until the optimum cooking time) on the quality of different resistant starch included in products by using an in vitro enzymatic hydrolysis method. Results showed that the applied, conventional pasta extrusion step had only a small effect on the liberated glucose level and did not influence the RS content significantly. The cooking in contrast caused an increased digestibility and the lost of resistance of all pasta products. The digestibility was significantly lower (p < 0.05) in the case of raw and dried samples compared to the cooked pastas. It can be concluded that the resistant starches used in the samples are heat sensitive and their properties change radically during the pasta preparation, mainly during cooking.     

Development of gluten-free fresh egg pasta based on oat and teff flour

Due to increased awareness of consumers about the relationship between food and health as well as the requirements of people following a gluten-free diet, the production of cereal products from raw materials other than wheat is of interest. However, the elimination of the visco-elastic gluten protein represents a technological challenge. During this study, response surface methodology was applied to determine optimal formulations for the production of egg pasta from oat and teff flour. Wheat flour was used as a control. The resulting products were characterised regarding firmness and elasticity, stickiness and cooking loss. The results showed that the mechanical texture of oat and teff pasta was comparable to wheat pasta, however, elasticity was significantly reduced. Compositional analysis was carried out on flour raw materials as well as on the final pasta products, showing that regarding fibre and mineral content, oat and teff samples are nutritionally superior to wheat. In addition, the microstructure was investigated by means of scanning electron microscopy, allowing also the observation of structural changes occurring during cooking. Upon cooking, a distinct outer layer can be observed, resulting from protein denaturation and starch gelatinisation. This structural feature is clearly visible for cooked wheat pasta and but is less apparent for teff and oat pasta.     

Functional,Thermal and Rheological Properties of High Fibre Fresh Pasta: Effect of Tiger Nut Flour and Xanthan Gum Addition

Tiger nut flour (TNF) is a rich source of dietary fibre with potential to be used in cereal-based products. However, research on improving the rheological properties of tiger nut-based doughs is limited. In this paper, the significance of TNF and xanthan gum (X) incorporation into fresh egg pasta, in terms of its thermal and dynamic rheological properties, has been investigated. Plain semolina pasta (DWS) was used as control. High fibre doughs (20 and 40% TNF) with or without X (0 and 1%) were assessed. Both fundamental (dynamic oscillatory and creep tests) and empirical (texture profile analysis) tests were performed to assess the viscoelasticity of TNF-DWS composite blends. Raw solids (TNF, DWS) were characterised in terms of their chemical composition, particle size distribution and functional properties. For both fresh and cooked pasta, water activity, water content and gelatinisation temperatures were estimated. The results from the rheological tests revealed that partial replacement of DWS by TNF lead to less cohesive and weaker structures due to the lower presence of a gluten network. X significantly improved the rheological response of the TNF-based doughs. Thermal analysis showed a single endothermic peak in the temperature range between 60 and 78 °C during heating, which corresponds to the amylopectin gelatinisation. However, when replacing 40% of DWS by TNF, two-phase transitions were observed, probably associated to the starch tiger nut gelatinisation or the formation of amylose-lipid complexes. The optimum cooking time for the tiger nut pasta was 2 min as determined by a calorimetric analysis.     

Pasta noodles enriched with sweet potato starch: Impact on quality parameters and resistant starch content

This research is focusing on the texture, rheology, and sensory properties of pasta products enriched with the sweet potato starch (SPS) as well as on the content of resistant starch (RS) in these products. SPS was extracted from orange sweet potatoes using 1 mol. L⁻¹ Sodium chloride solution. Durum wheat flour semolina was partially supplemented with 10, 20, and 30% (w/w) by SPS in the pasta formulation and the influence of enrichment on the cooking quality, mechanical and sensory properties, and the color was observed. SPS addition resulted in decreased water absorption and shorter dough development time, but the stability of the dough was also decreased. The optimum cooking time for pasta was reduced, but only slightly, on the other side, the swelling index increased, which negatively impacted on the firmness of the products. Increasing of the SPS content also resulted in higher stickiness values for pasta. When up to 20% of wheat flour was replaced, the color of finished products was less acceptable. In the products, the resistant and total starch content were determined. Pasta cooking resulted in the reduction of RS content, which was then increased by storing products for 24 hr. It can be concluded that the substitution of part of semolina flour with SPS increased the level of RS, but on the other side, it caused some significant differences from the quality of pasta made from semolina only.     

Analysis of ingredient functionality and formulation optimization of pasta supplemented with peanut flour

The working peanut pasta formulation range determined from a previous study was used to determine the effects of varying ingredient quantities and processing conditions on the pasta's quality and consumer acceptance. The variables studied were percent peanut flour substituted for durum wheat flour (30%, 40%, and 50%), amount of carrageenan (2.4%, 2.65%, and 2.9%), and drying temperature (60, 74, and 88 °C) on the final cooked pasta quality. Properties measured include color, texture, moisture content, and cooking loss. A home-use sensory test was conducted to determine consumer preferences and the optimum range for variables studied. Color lightness values ranged from 43.53 to 65.02, decreasing (becoming darker) with increased peanut flour level and increased drying temperature. Maximum cutting force for cooked pasta ranged from 1.59 N to 3.22 N, with higher values only for pasta dried at 88 °C. Moisture content ranged from 57.35% to 69.38%, and values decreased as drying temperature increased. Cooking loss ranged from 5.14% to 7.99%, increasing with higher levels of peanut flour and decreasing with higher levels of carrageenan. When prepared with 30% peanut flour and dried at 60 °C, the pasta was lighter in color, higher in moisture, and softer in texture than the varieties dried at higher temperatures and made with higher levels of peanut flour. Response surface analysis of consumer test data revealed that the optimum peanut pasta should contain between 35% and 45% peanut flour and should be dried between 60 and 71 °C; however, the pasta with 30% peanut flour was also a popular sample in the "favorite" categories. Practical Application: Most non-gluten protein fortification studies in durum wheat pasta found decreased firmness of dry and cooked pasta, increased cooking loss, increased stickiness, and darker product color when compared to traditional pasta. Partially defatted peanut flour is a versatile food ingredient and has high protein content. Since the lysine content of peanuts is higher than wheat, peanuts can be used to supplement wheat flour in food preparation. This study found by partially replacing wheat flour with peanut flour and with incorporation of hydrocolloid emulsifier, such as carrageenan or xanthan gum, dough viscosity, and pasta firmness significantly improved. Peanut pasta with high protein content and balanced amino acid profile can help support consumers with a healthy lifestyle.     

Studies on Rye Starch Properties and Modification. Part II: Swelling and Solubility Behaviour of Rye Starch Granules

Rye starch shows the typical inhibited swelling behaviour of triticeae starches with an onset of swelling at rather low temperature (50–55°C). Swollen rye starch granules exist as individuals even after swelling at 100°C. The total dispersion of rye starch needs temperatures above 120°C with pressure cooking. On heating of the rye starch suspension preferentially amylose is leached. Defatting of rye starch exhibits no influence on swelling power but results in higher solubility and in increased amylose leaching. The drying procedures applied here resulted in stronger assoziation of the polymer molecules in the starch granule leading to higher swelling temperatures and a reduced solubility. Shiftings of the crystalline/ amorphous-ratio of the starch granules as caused by different drying procedures, had no influence on the results of swelling power investigation but the highest swelling enthalpy as well as Brabender viscosity were exhibited by a sample dried at room temperature. It is proved to be possible to change the swelling behaviour of rye starch to “potato starch type” by slight chemical modification like succination.     

Effect of insoluble dietary fibre addition on technological,sensory, and structural properties of durum wheat spaghetti

Insoluble fibres are important in human health and disease prevention and can be incorporated into food. High fibre pasta prepared with bran is typically inferior quality compared to durum pasta. This study compared spaghetti prepared from durum semolina substituted with various amounts of either durum bran or germ (pollard) dried at high temperature. Pasta was evaluated for cooking properties, texture, sensory, fibre content, antioxidant status (AO) and in vitro starch digestibility to determine the dose producing acceptable quality. Pollard at 10% substitution had minimal impact on quality with higher AO and fibre. Above 30%, pasta had undesirable colour, sensory properties and higher starch digestion. Although bran substituted pasta had undesirable sensory and technological properties, especially at 30% incorporation, it does provide more dietary fibre and antioxidants than regular pasta and does not affect starch digestibility. Interestingly, a significant amount of AO was retained in the cooked pasta. The study illustrates the value of structural analysis to explain observed technological properties of the product with fibre inclusion.     

Changes in kernel properties,in situ gelatinization,and physicochemical properties of waxy rice with inhibition of starch branching enzyme during cooking

The kernel properties, gelatinisation and physicochemical properties of rice were investigated in a waxy rice Guang-ling-xiang-nuo (GLXN) and its transgenic line GLXN-RNAi with inhibition of starch branching enzyme I/IIb. The volume swelling, water content and leached material of cooked kernels increased with increasing cooking time, but they were lower in GLXN-RNAi than in GLXN. The kernels of GLXN-RNAi were more difficultly gelatinised and disrupted than those of GLXN during cooking. The starch in the exterior of GLXN-RNAi endosperm was not completely gelatinised. The C_A-type starch of GLXN-RNAi was more resistant to cooking than A-type starch of GLXN. The cooked kernels of GLXN-RNAi had lower rapidly digestible starch and greater slowly digestible starch than those of GLXN. Brown rice flour had higher peak, hot, final and setback viscosities and lower breakdown viscosity in GLXN than GLXN-RNAi. These results indicated that GLXN-RNAi kernels exhibited great potential in applications as health foods.     

The influence of inulin addition on the morphological and structural properties of durum wheat pasta

The effect of the addition of different concentration of inulin fibre to durum wheat pasta was evaluated in terms of structure, texture and morphological characteristics. Inulin fibre fraction was incorporated into pasta at 5%, 10% and 15% inclusion rates. Changes to pasta quality were observed with inulin fibre fraction addition by scanning electron microscopy, X-ray diffraction and Raman spectroscopy methods. Investigation of pasta microstructure indicate a lowering in crystallinity increasing the inulin content and characterisation of starch gelatinisation events indicated that a combination of changes to the starch–protein matrix and the high water-binding capacity of inulin alters the physico-chemical properties and then the digestibility of the pastas.     

Structuring and texturing gluten-free pasta: egg albumen or whey proteins?

The effects of adding egg albumen or whey proteins to pasta made from parboiled rice flour (PR) were investigated. Pasta quality was evaluated in terms of color, furosine content, and cooking properties (water absorption, cooking loss, and consistency at the optimal cooking time). The surface heterogeneity of the cooked and uncooked materials was studied, and some starch properties (pasting properties and starch susceptibility to α-amylase hydrolysis) were assessed, along with the features of the protein network as determined by conditional solubility studies and with ultrastructural features of the cooked products. Egg albumen improved pasta appearance and gave a product with low cooking loss, firmer, and nutritionally more valuable than the other ones. In albumen-enriched pasta, small starch granules appear homogeneously surrounded by a protein network. In the uncooked product, the protein network is stabilized mostly by hydrophobic interactions, but additional disulfide interprotein bonds form upon cooking. Thus, addition of 15 % liquid albumen to PR results in significant improvement of the textural and structural features of rice-based gluten-free pasta.     

Wheat noodles enriched with A-type and/or B-type wheat starch: physical,thermal and textural properties of dough sheet and noodle samples from different noodle-making process

This study explored the effects of adding A-type starch (AS), B-type wheat starch (BS) on the physicochemical or edible quality of dough sheet and noodle samples at different stages of the noodle-making process, which included 1-mixing, 2-kneading, 3-resting, 4-sheeting and cutting and 5-drying. The swelling power and pasting viscosities of samples in noodle-making process were decreased compared with mixed flour, indicating gluten network during noodle-making inhibits these properties of starch. Adding 20% BS enhanced the formation and aggregation of gluten network during kneading and drying compared by adding AS. The drying process increased cooking yield and cooking loss and decreased hardness and springiness, and the effect was weakened when adding BS. The correlation results show the increased solubility and decreased setback during drying are the main reason for the changes of cooking and texture quality of noodles. The increase of swelling power resulted in the increased cooking yield.     

Redox agents and N-ethylmaleimide affect the extractability of gluten proteins during fresh pasta processing

The gluten protein network is of great importance for pasta cooking quality. Redox agents were used as a tool to impact the protein network formation during laboratory scale fresh pasta making (mixing and sheet rolling) and cooking. SE- and RP-HPLC data showed that disulphide bonds are formed in the pre-existing gluten protein network during cooking of fresh pasta and that, in the process, glutenin polymerisation occurs faster than gliadin–glutenin copolymerisation. The thiol blocking agent N-ethylmaleimide (245 ppm, expressed on semolina, dry basis) and, to a lesser extent, the oxidising agent potassium iodate (70 ppm), hindered glutenin polymerisation and gliadin–glutenin copolymerisation during cooking. However, the introduction of reactive thiol groups, by addition of the reducing agent glutathione (100 ppm), resulted in faster gliadin–glutenin copolymerisation during cooking.     

Evaluation of potential mechanisms by which dietary fibre additions reduce the predicted glycaemic index of fresh pastas

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.     

Structure-quality relationship in commercial pasta: a molecular glimpse

Presence and stability of a protein network was evaluated by fluorescence spectroscopy, by protein solubility studies, and by assessing the accessibility of protein thiols in samples of commercial Italian semolina pasta made in industrial plants using different processes. The pasting properties of starch in each sample were evaluated by means of a viscoamylograph. Magnetic resonance imaging (MRI) was used to evaluate water distribution and water mobility in dry pasta, and at various cooking times. The molecular information derived from these studies was related to sensory indices, indicating that protein reticulation was dependent on the process conditions, which affected water penetration, distribution, and mobility during cooking. Products with a crosswise gradient of water mobility once cooked had the best sensory scores at optimal cooking time, whereas products with a less compact protein network performed better when slightly overcooked.