Effect of soluble fibre (guar gum and carboxymethylcellulose) addition on technological, sensory and structural properties of durum wheat spaghetti

Incorporation in pasta of either of two soluble fibres, carboxymethylcellulose sodium salt (CMC) and guar gum (GG), was found to significantly reduce the rate of invitro starch digestion. The amount of reducing sugars produced over 300 min was reduced by 18% at 1.5% CMC incorporation and 24% at 20% GG incorporation. Negative effects on sensory and technological properties were seen at the high levels of GG needed to reduce the rate of in vitro digestion, and a ‘matty’ layer covering the surfaces of starch granules was observed by scanning electron microscopy and confocal scanning laser microscopy. By contrast, levels of CMC incorporation giving large reductions in in vitro digestion had no negative effects on pasta properties. No significant alteration in pasta structure on CMC incorporation was observed by microscopy. The large difference in the amounts of soluble fibre required to bring about equivalent reductions in digestion rate suggests that different mechanisms may be involved in the two cases.     

Studying physiochemical changes in a new pasta product containing beef heart by vibrational spectroscopy

A new pasta product was developed by partially replacing durum wheat flour with beef heart to enhance its nutritional value. Physiochemical changes of the pasta were investigated by vibrational spectroscopy, namely Fourier transform infrared (FT-IR) and Raman spectroscopy. Relationships between pasta texture and the intensity of vibrational spectra were established. Lipid-protein complex formation, β-sheet arrangement, degree of polysaccharide polymerization, and cysteine thiol group were related to hardness and chewiness of pasta. The lipid portion and β-sheet structure were two significant parameters for explaining pasta adhesiveness, while pasta firmness might be related to β-sheet alignment and the polysaccharide network. Pasta cohesiveness might involve the α-helical structures and hydrogen bonding formation in the gluten network. However, no variable met the p < 0.1 significance level for inclusion into the model to explain pasta springiness. These results reveal that FT-IR and Raman spectroscopy could be employed to evaluate the physical chemistry of pasta and showed a potential use for quality assessment in pasta products.     

Enhancement of pasta antioxidant activity with oregano and carrot leaf

Five different pasta formulations were prepared using different concentrations of carrot leaf meal (CLM) and oregano leaf meal (OLM). One control formulation (wheat flour and semolina, 70:30 w/w) and four other formulations were prepared using the following amounts of leaf meals: 5% CLM and 5% OLM (I), 10% CLM (II), 10% OLM (III), and 10% CLM, 10% OLM (IV). The highest content of alpha-linolenic acid was found in formulations II and IV, which also had a reduced n-6/n-3 ratio, 3.6 (IV), when compared to the control, which was 19.8. All the samples enhanced with leaf meals showed antioxidant activity by the DPPH radical method; however, it was higher in formulation IV, which was the same observed for phenolic compounds. Pasta added with leaf meals lost more solubles, had shorter cooking time and a lower weight increase than the control pasta. All formulations had significant sensory acceptance.     

Effect of transglutaminase on the quality of wheat-based pasta products

Transglutaminase (TG) enzyme was tested in T. aestivum and T. durum wheat-based model systems to evaluate the quality improvement to pasta imparted by cross-linking. Quality was measured by the enhancement in sensory and cooking properties. In this process, tests were also performed to establish the biochemical structure-functions of the proteins involved at TG enzyme concentrations between 10 and 200 mg kg⁻¹. It was observed that the amounts of water/salt-, the alcohol- and the alkali-soluble protein fractions were reduced significantly. Change in the molecular weight distribution assessed by SDS PAGE was also noticed. The sensory properties were observed to improve from high water uptake and low cooking loss. The TG treatment changed the gluten structure in the modified pasta products. Immune-reactive gliadin fractions were detected by immunoblotting and independently measured by competitive indirect ELISA, using the anti-gliadin rabbit IgG.     

Effects of curd heating with or without previous milk pasteurisation on the microbiological quality and safety of craft‐made ‘Pasta Filata’ Kashkaval cheese curds

An empirical ‘Pasta Filata’ process used for traditional Kashkaval cheese manufacture from raw ewes’ milk improved the hygiene of fresh curd. Coagulase‐positive (RPF+) staphylococci and coliforms declined by 2.4 and 4.5 log units, respectively, and Listeria contamination was minimised. Before Pasta Filata, RPF+ staphylococci exceeded the 5‐log threshold level specified in EC Regulation 1441/2007 in raw milk curds despite the prevalence of indigenous mesophilic lactic acid bacteria. Pasta Filata favoured enterococci in raw milk curds. Pasteurisation enhanced prevalence of Streptococcus thermophilus and Lactococcus lactis starters and microbial quality and safety of pasteurised milk curds before and particularly after Pasta Filata.     

Evolution of porosity, shrinkage and density of pasta fortified with pea protein concentrate during drying

The aim of this work was to study the impact of fortification with commercial pea protein concentrate on the evolution of the moisture content, density, shrinkage and porosity of pasta made from durum wheat semolina during drying. Pasta were processed from durum wheat semolina enriched with pea protein concentrate at 0, 5, 10 and 15 g 100-g-dry matter⁻¹ and dried at low (40 °C) and high (80 °C) temperature. Moisture content, density, shrinkage and porosity and effective moisture diffusivity coefficients were linked through theoretical development. It enabled to study the behaviour of the properties as a function of drying time. The results showed that drying temperature has a greater effect on the studied properties than enrichment with pea protein concentrate. Drying at 80 °C increased radial and total shrinkage compared to drying at 40 °C, but no differences were observed for longitudinal shrinkage. Pasta dried at 80 °C were denser and overall less porous, but had greater internal porosity. The volumetric percentage of water lost during drying replaced by air within the pasta matrix was lower at 80 °C. Scanning electron microscopy analysis showed that the gluten network of pasta dried at 80 °C seems denser and more continuous. Effective moisture diffusivity coefficients of pasta dried at 80 °C were higher at 5 and 10 g 100-g-dry matter⁻¹ enrichment level compared to the control.     

Can variation in durum wheat pasta protein and starch composition affect in vitro starch hydrolysis?

Pasta was prepared with modifications designed to alter its rate of digestion, including altering the ratio of A- to B-granules, incorporating higher amylose content, and varying the glutenin:gliadin ratio and HMW:LMW glutenin subunit ratio. The effects of these modifications were investigated using an in vitro hydrolysis method. A significant reduction in parameters related to glycaemic index was established for high amylose pastas and pastas with 40% B-granule composition, while most other modifications increased the rate of starch hydrolysis. All effects observed were small in comparison to the effect on glycaemic index previously obtained by addition of soluble fibres.     

Deoxynivalenol and its masked forms: Characteristics,incidence, control and fate during wheat and wheat based products processing - A review

BackgroundDeoxynivalenol (DON) is a toxic secondary metabolite primarily produced by Fusarium graminearum and Fusarium culmorum that is common in grains, such as wheat and wheat-based products.Scope and approachThis review points out on the main DON-producing fungi, the factors affecting DON production, its toxicological aspects and preventive measures to avoid contamination of foods by DON. Further, the article discusses the fate of DON throughout the processing of wheat, bread, and pasta and finally critically assesses data on the impact of specific steps of processing on DON contents in wheat-based products.Key findings and conclusionsThe proposed controls at pre- and post-harvest stages seem to comprise the most efficient strategies to manage the incidence of DON in wheat and wheat-based products. Prevention of plant infection by Fusarium species, managing crops and ensuring the rapid drying of wheat after harvest is the effective approaches for the elimination of DON contamination. There has been contradictory data in the literature on the fate of DON during wheat and wheat-based products processing Due to differences in processing, such as temperature, additives, processing time and loaf size in addition to the occurrence of modified (masked) forms of DON. Therefore, further research must be carried out aiming to reveal the formation and occurrence of modified forms of DON. These compounds can be formed throughout wheat processing, from pre-harvest to processing of wheat-based products, and for proper quantification, analytical methods able to quantify modified forms of DON are required.     

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.     

Effects of toasting on the carbohydrate profile and antioxidant properties of chickpea (Cicer arietinum L.) flour added to durum wheat pasta

The effects of the toasting process on the carbohydrate profile and antioxidant properties of chickpea flour were studied, along with the cooking behaviour, and antioxidant and nutritional properties of pasta enriched with the chickpea flour. The toasting process increased the resistant starch, insoluble dietary fibre and antioxidant properties of the flour. Addition of chickpea flour (raw and toasted) to durum wheat semolina changed the carbohydrate profile in the uncooked and cooked enriched pasta, especially with the toasted chickpea, and worsened the overall quality of the pasta. The increase in total phenolic content and total free phenolic acid content in the uncooked pasta was due to positive effects of addition of the chickpea flours, while the increase in the bound phenolics fraction in the cooked pasta was from the durum wheat, which was crucial for its high concentrations of ferulic acid. The increase in the free fraction of the Trolox equivalent antioxidant capacity in cooked pasta was consistent with the addition of chickpea.