Submerged fermentation of lentil protein isolate and its impact on protein functionality, nutrition, and volatile profiles.

Fermentation of pulses as a clean processing technique has been reported to have a favorable impact on the functional and nutritional quality of the starting materials. Compared to commonly fermented pulses such as peas and chickpeas, limited information is available on the effect of fermentation on lentils, especially when using a high protein isolate (>80% protein) as compared to seeds or flours. Therefore, in the present work, lentil protein isolate was used as a feedstock for submerged fermentation with Aspergillus niger, Aspergillus oryzae, or Lactobacillus plantarum. After 48 h, the samples showed increased protein content with enhanced solubility and oil-holding capacity. Controlled fermentation, as opposed to spontaneous fermentation, maintained the high foaming capacity; however, all fermented samples had lower foam and emulsion stabilizing properties and reduced water-holding capacity compared to the control. The fermented proteins were also less digestible, possibly due to an increase in phenolics and saponins. New volatile compounds were identified in fermented samples that show promise for improved sensory attributes. Significant differences were observed in specific quality attributes depending on the microbial strain used. Further research is required to better understand the fermentative metabolism of microbial communities when provided high-protein lentil ingredients as growth substrates. PRACTICAL APPLICATION: Fermented lentil protein isolate has promising flavor profiles that may improve its sensory properties for food application.

Effects of extrusion screw speed, feed moisture content, and barrel temperature on the physical, techno-functional, and microstructural quality of texturized lentil protein.

Utilizing lentil protein as a novel ingredient for producing texturized vegetable proteins (TVPs) can provide new opportunities for the production of next-generation hybrid meat products. TVPs from lentil protein isolate were manufactured using low-moisture extrusion cooking at different combinations of screw speed (SS), feed moisture content (MC), and barrel temperature (BT) profile. In total, seven different combinations of processing treatments were tested, and the resulting TVPs were characterized for their physical (rehydration ratio, texture profile analysis, color, and bulk density), techno-functional (oil and water holding capacities), and microstructural properties. The processing conditions of higher SS and lower MC resulted in increased values of several textural profile attributes (springiness, cohesiveness, and resilience), increased water holding capacity (WHC), and decreased bulk density. Compared to raw lentil protein, TVPs showed enhanced oil holding capacity, though WHC either decreased or remained constant. The extrusion response parameters (die pressure, torque, and specific mechanical energy) showed positive correlations with several physical properties (texture, WHC, and total color change), revealing their potential for serving as important TVP quality indicators. TVPs produced at SS, MC, and BT of 450 rpm, 30%, and 140°C, respectively, showed relatively better overall physical and techno-functional quality and can be used as meat extenders in hybrid meat patties. Overall, this research evidenced the viability of lentil protein as a potential ingredient for producing low-moisture TVPs.

Contribution of home garden vegetables on reducing stunting among 6- to 23-month-old children in South Tigray, northern Ethiopia.

The study was conducted to analyze the contribution of home garden vegetables in reducing stunting among 6- to 23-month-old children from South Tigray, Northern Ethiopia. The quasi-experimental study design was used. Multistage sampling technique was used to select the districts and study communities. A total of 94 purposively selected vegetable producer (intervention) households and 260 randomly selected non-producer (control) households were included in the study (1:3 ratio). The recumbent length of children was measured using horizontal wooden board to the nearest 0.1 cm. The length-for-age Z-scores were computed using WHO-Anthro 2006 software. Propensity score-matching and difference-in-difference (DID) estimates were used to analyze data using STATA software version 12. Prevalence of child stunting was 19.8 (12.7-29.4) and 21.1 (16.4-26.7)% (baseline) and 43.5 (33.5-54.1) and 46.5 (45.7-47.2)% (end line) among intervention and control groups, respectively. Child stunting was higher for boys and older children from both intervention and control households. DID estimation revealed that there was no significant difference in child stunting between intervention and control households (DID = 1.7, p = .604). However, there was an intervention effect of -0.5, 2.5, and 1.7% in the prevalence of child stunting among females, males, and both sexes, respectively. Vegetable production as an intervention strategy reduced the prevalence of stunting in children aged 6-23 months. However, vegetable production needs to be well integrated with other nutrition-sensitive interventions to realize the objective of reducing child stunting.

Bioengineered Enzymes and Precision Fermentation in the Food Industry.

Enzymes have been used in the food processing industry for many years. However, the use of native enzymes is not conducive to high activity, efficiency, range of substrates, and adaptability to harsh food processing conditions. The advent of enzyme engineering approaches such as rational design, directed evolution, and semi-rational design provided much-needed impetus for tailor-made enzymes with improved or novel catalytic properties. Production of designer enzymes became further refined with the emergence of synthetic biology and gene editing techniques and a plethora of other tools such as artificial intelligence, and computational and bioinformatics analyses which have paved the way for what is referred to as precision fermentation for the production of these designer enzymes more efficiently. With all the technologies available, the bottleneck is now in the scale-up production of these enzymes. There is generally a lack of accessibility thereof of large-scale capabilities and know-how. This review is aimed at highlighting these various enzyme-engineering strategies and the associated scale-up challenges, including safety concerns surrounding genetically modified microorganisms and the use of cell-free systems to circumvent this issue. The use of solid-state fermentation (SSF) is also addressed as a potentially low-cost production system, amenable to customization and employing inexpensive feedstocks as substrate.

Quantitative trait loci associated with amino acid concentration and in vitro protein digestibility in pea (Pisum sativum L.).

With the expanding interest in plant-based proteins in the food industry, increasing emphasis is being placed on breeding for protein concentration and quality. Two protein quality traits i.e., amino acid profile and protein digestibility, were assessed in replicated, multi-location field trials from 2019 to 2021 in pea recombinant inbred line population PR-25. This RIL population was targeted specifically for the research of protein related traits and its parents, CDC Amarillo and CDC Limerick, had distinct variations in the concentration of several amino acids. Amino acid profile was determined using near infrared reflectance analysis, and protein digestibility was through an in vitro method. Several essential amino acids were selected for QTL analysis, including lysine, one of the most abundant essential amino acids in pea, and methionine, cysteine, and tryptophan, the limiting amino acids in pea. Based on phenotypic data of amino acid profiles and in vitro protein digestibility of PR-25 harvested in seven location-years, three QTLs were associated with methionine + cysteine concentration, among which, one was located on chromosome 2 (R2 = 17%, indicates this QTL explained 17% phenotypic variation of methionine + cysteine concentration within PR-25), and two were located on chromosome 5 (R2 = 11% and 16%). Four QTLs were associated with tryptophan concentration and are located on chromosome 1 (R2 = 9%), chromosome 3 (R2 = 9%), and chromosome 5 (R2 = 8% and 13%). Three QTLs were associated with lysine concentration, among which, one was located on chromosome 3 (R2 = 10%), the other two were located on chromosome 4 (R2 = 15% and 21%). Two QTLs were associated with in vitro protein digestibility, one each located on chromosomes 1 (R2 = 11%) and 2 (R2 = 10%). QTLs associated with in vitro protein digestibility, and methionine + cysteine concentration on chromosome 2 were identified to be co-localized with known QTL for total seed protein concentration in PR-25. QTLs associated with tryptophan and methionine + cysteine concentration co-localized on chromosome 5. The identification of QTLs associated with pea seed quality is an important step towards marker-assisted selection of breeding lines with improved nutritional quality, which will further boost the competitiveness of pea in plant-based protein markets.

Educational intervention and livestock ownership successfully improved the intake of animal source foods in 6-23 months old children in rural communities of Northern Ethiopia: Quasi-experimental study.

BACKGROUND: Animal source foods (ASFs) are rich in high-quality proteins, including essential amino acids and highly bioavailable micronutrients vital for child growth and cognitive development. But, the daily consumption of ASFs among 6-23 months old children is very low in Tigray, Northern Ethiopia. OBJECTIVE: The study aimed to assess the effectiveness of nutrition education intervention to improve the consumption of ASFs among 6-23 months old children from rural communities with strict religious fasting traditions of avoiding intake of ASFs in Northern Ethiopia. METHODS: A quasi-experimental study was conducted in two food insecure districts namely Samre Seharti (intervention) and Tanqua Abergele (comparison). The mother-child pairs in the intervention group (n = 140) received nutrition education based on the barriers and available resources for optimal consumption of ASFs among children and followed up for nine months. The mother-child pairs in the comparison group (n = 153) received routine nutrition education. The data were collected using a pre-tested structured questionnaire. The baseline and endline data assessment included interviews on socio-demographic and socio-economic status, dietary intake, and child feeding practices. The effectiveness of the intervention was measured using the difference-in-difference (DID) analysis model. RESULTS: At endline, the consumption of ASFs among children was 19.5 percentage points higher in the intervention group compared with the comparison group (p = 0.008). In addition, there was a significant increase in egg consumption among children in the intervention group (DID of 16.9, p = 0.012) from the comparison group. No child was consuming meat at baseline in both the intervention and comparison arms and it was very low at endline (5.2% vs. 7.9%). Overall, the proportion of children that consumed eggs in the intervention group was higher than in the comparison group in households that owned sheep and goats (4.8% vs. 21.4%, p = 0.050) and chicken (6.3% vs. 43.8%, p = 0.002) after education interventions. However, no statistically significant difference was observed between cow ownership and milk consumption among children (p>0.05). CONCLUSIONS: Age-appropriate educational interventions for mothers and owning small livestock in the household can improve the consumption of ASFs and eventually the minimum diet diversity of children in communities with strict religious traditions of avoiding ASFs during the fasting seasons.

Conversion of Pulse Protein Foam-Templated Oleogels into Oleofoams for Improved Baking Application.

The food industry has long been searching for an efficient replacement for saturated-fatty-acid-rich fats for baking applications. Although oleogels have been considered a potential alternative for saturated and trans fats, their success in food application has been poor. The present study explored the use of oleofoams obtained by whipping the pulse protein foam-templated oleogels for cake baking. Oleogels were prepared at room temperature by adding canola oil containing high-melting monoglyceride (MAG) or candelilla wax (CW) to the freeze-dried pea or faba bean protein-stabilized foams. Oleogels were then whipped to create the oleofoams; however, only the oleogels containing MAG could form oleofoams. CW-oleogel could not form any oleofoam. The most stable oleofoams with the highest overrun, stability, and storage modulus were obtained from 3% MAG+pulse protein foam-templated oleogels. The MAG plus protein foam-templated oleogels showed smaller and more packed air bubbles than MAG-only oleofoam, which was ascribed to the protein's ability to stabilize air bubbles and provide a network in the continuous oil phase to restrict air bubble movement. A novel batter preparation method for oleofoam was developed to increase air bubble incorporation. The X-ray microtomography images of the cakes showed a non-homogeneous distribution of larger air bubbles in the oleofoam cake compared to the shortening cake although their total porosity was not much different. The oleofoam cakes made with the new method yielded similar hardness and chewiness compared to the shortening cakes. By improving rheology and increasing air incorporation in the batter, high-quality cakes can be obtained with MAG-containing oleofoams made from pulse protein foam-templated oleogels.

Developing Value-Added Protein Ingredients from Wastes and Byproducts of Pulses: Challenges and Opportunities.

Wastes and byproducts of pulse processing carry a potential for utilization as raw materials for extraction of protein ingredients. This work is an overview of the extraction and fractionation techniques used for obtaining protein ingredients from wastes and byproducts of pulse processing, and it presents several characteristics of proteins extracted in terms of composition, nutritional properties, and functional properties. Several extraction methods have been applied to obtain protein ingredients from pulse processing wastes and byproducts. Each extraction technique is indicated to have significant effects on protein composition and functionality which could also affect the performance of proteins in different food applications. Versatile end product applications of protein ingredients obtained from pulse processing wastes and byproducts are yet to be discovered. Research is lacking on the limitations and improvement methods for using wastes and byproducts of pulses for protein extraction. This review provides insights into the possible applications of innovative extraction technologies for obtaining protein ingredients from wastes and byproducts of pulses. Further research has to focus on various modification techniques that can be applied to improve the functional, nutritional, and sensory properties of proteins extracted from pulse processing wastes and byproducts.

Microencapsulation of Flaxseed Oil by Lentil Protein Isolate-κ-Carrageenan and -ι-Carrageenan Based Wall Materials through Spray and Freeze Drying.

Lentil protein isolate (LPI)-κ-carrageenan (κ-C) and -ι-carrageenan (ι-C) based microcapsules were prepared through spray-drying and freeze-drying to encapsulate flaxseed oil in order to reach final oil levels of 20% and 30%. Characteristics of the corresponding emulsions and their dried microcapsules were determined. For emulsion properties, all LPI-κ-C and LPI-ι-C emulsions remained 100% stable after 48 h, while the LPI emulsions destabilized quickly (p < 0.05) after homogenization mainly due to low emulsion viscosity. For spray-dried microcapsules, the highest yield was attributed to LPI-ι-C with 20% oil, followed by LPI-κ-C 20% and LPI-ι-C 30% (p < 0.05). Flaxseed oil was oxidized more significantly among the spray-dried capsules compared to untreated oil (p < 0.05) due to the effect of heat. Flaxseed oil was more stable in all the freeze-dried capsules and showed significantly lower oil oxidation than the untreated oil after 8 weeks of storage (p < 0.05). As for in vitro oil release profile, a higher amount of oil was released for LPI-κ-C powders under simulated gastric fluid (SGF), while more oil was released for LPI-ι-C powders under simulated gastric fluid and simulated intestinal fluid (SGF + SIF) regardless of drying method and oil content. This study enhanced the emulsion stability by applying carrageenan to LPI and showed the potential to make plant-based microcapsules to deliver omega-3 oils.

Comparison of Protein Content, Availability, and Different Properties of Plant Protein Sources with Their Application in Packaging.

Plant-based proteins are considered to be one of the most promising biodegradable polymers for green packaging materials. Despite this, the practical application of the proteins in the packaging industry on a large scale has yet to be achieved. In the following review, most of the data about plant protein-based packaging materials are presented in two parts. Firstly, the crude protein content of oilseed cakes and meals, cereals, legumes, vegetable waste, fruit waste, and cover crops are indexed, along with the top global producers. In the second part, we present the different production techniques (casting, extrusion, and molding), as well as compositional parameters for the production of bioplastics from the best protein sources including sesame, mung, lentil, pea, soy, peanut, rapeseed, wheat, corn, amaranth, sunflower, rice, sorghum, and cottonseed. The inclusion of these protein sources in packaging applications is also evaluated based on their various properties such as barrier, thermal, and mechanical properties, solubility, surface hydrophobicity, water uptake capacity, and advantages. Having this information could assist the readers in exercising judgement regarding the right source when approving the applications of these proteins as biodegradable packaging material.

The influence of fasting on energy and nutrient intake and their corresponding food sources among 6-23 months old children in rural communities with high burden of stunting from Northern Ethiopia.

BACKGROUND: Limited studies in Ethiopia showed that infants and young children are at high risk of inadequate intake of energy and nutrients. However, inclusive assessment of both nutrient intakes and their food sources are lacking. We aimed at assessing energy and nutrient intakes and their food sources during religious fasting and non-fasting periods among 6-23 months old children in Northern Ethiopia. METHODS: Data for this longitudinal study were collected following repeated multiple-pass 24-h dietary recall technique through face-to-face interviews with primary caregivers. Using a two-stage systematic random sampling method, a total of 570 and 551 children participated respectively in the lent fasting and non-fasting periods. Energy and nutrient intakes were estimated and compared with WHO daily requirements. All foods that a child consumed on the day preceding the date of data collection were recorded and processed with database software. Chi-square and t- tests were used to analyze the data. Non-normally distributed data were analyzed using Wilcoxon signed-rank test and statistical significance was set at p < 0.05. RESULTS: The overall prevalence of child stunting was 41.4%. Almost all of children (99.6%) consumed grains, roots, and tubers. The inadequacy prevalence of energy, protein and eight selected micronutrients (calcium, iron, zinc, vitamin A, thiamin, riboflavin, niacin, vitamin C) intake were 96.2, 44.9, and 95.5%, respectively. Calcium and zinc were the highest (100%) deficits observed across all age groups. Although consumption of animal source foods (ASFs) was very low (dairy 10.1%, meat 2.3% and eggs 23.6%), there was significantly higher consumption of meat and eggs during the non-fasting compared to fasting period (p < 0.001). CONCLUSIONS: Inadequate intake of energy and nutrients was common among 6-23 months old children. Cereals were found to be the main sources of many of the nutrients. The consumption of ASFs among 6-23-month-old children was low which was also affected by the religious fasting period. Hence, strengthening social and behavior change communication, supporting rural households to raise poultry and small ruminants is recommended.

Effect of roasting pulse seeds at different tempering moisture on the flour functional properties and nutritional quality.

Knowledge on the functional and nutritional properties of wet roasted pulses can increase the utilization of processed pulses as ingredients in food products. This study investigated the effects of tempering different pulse [chickpea (CP), green lentil (GL), navy bean (NB) and yellow pea (YP)] seeds to 20 or 30% moisture prior to roasting (160℃ for 30 min) on the functional properties and nutritional quality of their resulting flours. The surface charge of each pulse remained the same (p > 0.05) after wet roasting and there were no significant (p > 0.05) differences between the different raw pulse flours. The oil holding capacity (OHC) of GL (~2 g/g) was not improved by wet roasting (p > 0.05) whereas the other pulses generally had better OHC for one or both of the tempering moistures used prior to roasting. Foaming properties of all pulses decreased after heat treatment with the exception of both foaming capacity (107%) and stability (~71%) for GL tempered to 20% moisture prior to roasting (p > 0.05). Raw GL had inferior foaming properties compared to the other raw pulse flours (p < 0.001). Emulsion properties of the wet roasted pulses were similar to those of the control (raw flour) for each pulse. Solubility decreased with roasting regardless of the tempering moisture (p < 0.05) whereas in general the in vitro protein digestibility increased. Small improvements (2.4-6.9% increase) in the in vitro protein digestibility-corrected amino acid score were found for GL and NB tempered to 20% moisture before roasting and roasted YP at either moisture content (p < 0.05). Wet roasting increased (p < 0.05) the rapidly digestible starch content, more so with a tempering moisture of 30%. Overall the results from this study will allow for the utilization of wet roasted pulses as ingredients based on their functional properties and protein quality.

Effect of different levels of esterification and blockiness of pectin on the functional behaviour of pea protein isolate-pectin complexes.

This research examines changes to the functional (solubility, emulsifying and foaming) properties of pea protein isolate when complexed with commercial citrus pectin of different structural attributes. Specifically, a high methoxy (P90; degree of esterification: 90.0%; degree of blockiness: 64.5%; galacturonic acid content 11.4%) and low methoxy (P29; degree of esterification: 28.6%; degree of blockiness: 31.1%; galacturonic acid: 70%) pectin at their optimum mixing ratios with pea protein isolate (4:1 pea protein isolate to P90; 10:1 pea protein isolate to P29) were assessed at the pHs associated with critical structure forming events during the complexation process (soluble complexation (pHc), pH 6.7 and 6.1; insoluble complex formation (pHϕ1), pH 4.0 and 5.0; maximum complexation (pHopt), pH 3.5 and 3.8; dissolution of complexes, pH 2.4 and 2.1; for admixtures of pea protein isolate-P90 and pea protein isolate-P29, respectively). Pea protein isolate solubility was improved from 41 to 73% by the presence of P90 at pH 6.0 and was also moderately increased at pH 4.0 and pH 5.0 by P90 and P29, respectively. The emulsion stability of both pea protein isolate-pectin complexes was higher than the homogeneous pea protein isolate at all critical pHs except pHopt as well as pHc for pea protein isolate-P29 only. P90, with the higher level blockiness and esterification, displayed better foaming properties at the maximal complexation pH when complexed with pea protein isolate than pea protein isolate-P29 or pea protein isolate alone. However at pHϕ2, pea protein isolate-P29 admixtures produced foams with 100% stability, increasing pea protein isolate foam stability by 85%. The enhanced functionality of pea protein isolate-pectin complexes based on the type of pectin used at critical pHs indicates they may be useful biopolymer ingredients in plant protein applications.

Complex coacervation of pea albumin-pectin and ovalbumin-pectin assessed by isothermal titration calorimeter and turbidimetry.

BACKGROUND: This study investigates the complexation of a pea albumin-rich fraction and ovalbumin with pectin of different degrees of esterification (DE) and blockiness (DB) as a function of pH and biopolymer mixing ratio by turbidimetric titration and isothermal titration calorimetry (ITC). RESULTS: Turbidimetric analysis found maximum complexation occurred at a mixing ratio of 4:1 for pea albumin with high methoxy pectin, 8:1 for pea albumin with low methoxy pectin, and 8:1 for ovalbumin with low methoxy pectin. In the case of ovalbumin with high methoxy pectin, interactions were very weak. The pectin with high levels of esterification and blockiness displayed greater interactions with the pea albumin in both turbidimetry and ITC. However, low methoxy pectin imparted better interactions with ovalbumin and displayed higher optical density values than high methoxy pectin. CONCLUSIONS: The current study indicated that the different thermodynamic parameters of PA-pectin complexes can be tuned by controlling the structural characteristics (DB, DE, and d-galacturonic acid) of the pectin. © 2020 Society of Chemical Industry.

Production of glycerol by Lactobacillus plantarum NRRL B-4496 and formation of hexamine during fermentation of pea protein enriched flour.

Suspensions of pea protein enriched flour (PP) inoculated with Lactobacillus plantarum NRRL B-4496 and uninoculated PP suspensions were incubated in vials covered with airtight caps. Organic compound compositions of fermented and unfermented PP suspensions (F-PP and U-PP, respectively) were analyzed using solid phase microextraction (SPME) coupled with gas chromatography - mass-spectrometry (GCMS). Acetic acid was detected in all samples; pH dropped from pH 6.5 to pH 4.1 in L. plantarum F-PP and to pH 5.3 in uninoculated F-PP. Abundance of acetic acid and minuscule presence of lactic acid in L. plantarum F-PP suggested that fermentation proceeded preferentially via the pyruvate formate lyase (PFL) pathway. Nonetheless, glycerol appeared to be the most abundant compound in L. plantarum F-PP samples; colorimetric analysis indicated that its average concentration in these samples was 1.05 g/L. A metabolic switch from the PFL pathway to glycerol production might occur due to acidity tolerance limitations of L. plantarum, glycerol production being associated with the release of phosphate, which can act as a buffer. Fermentation of PP by L. plantarum also led to formation of hexamine, which is a known food preservation agent. Presence of naturally formed hexamine and glycerol in food products may render using chemical additives needless.

Role of NaCl level on the handling and water mobility in dough prepared from four wheat cultivars.

In bread, NaCl plays a number of roles including improving flavor, functionality, dough handling, and prevention of sticky dough. Its reduction can create significant processing challenges. As such, the dough handling properties for four wheat cultivars (Pembina, Roblin, McKenzie, and Harvest) were investigated as a function of NaCl (0-4%) level. In terms of dough rheology, both cultivar and NaCl level were significant factors. The maximum deformation (Jmax ) in the dough decreased with increasing NaCl levels, indicating that the gluten network became stronger so that it was able to resist the imposed stress. For extensibility, increasing the levels of NaCl resulted in increased resistance to extension for all cultivars. Dough stickiness was shown to be both cultivar and salt level dependent, with weaker cultivars showing higher stickiness. Findings for water association indicated that with the addition of NaCl there was less free water among the different cultivars and an increase in the water associated with the starch-fraction. Dough morphology measurements supported rheology trends; the stronger dough producing cultivars created more elongated protein polymers with a unidirectional network whereas the weaker cultivars created porous multidirectional networks. Overall, Pembina and Roblin formed stronger gluten networks than McKenzie and Harvest, however, the effect of NaCl level was shown to be cultivar dependent. Findings indicate that careful cultivar selection will help mitigate challenges in dough handling within a reduced NaCl environment.

Effect of chemical oxidizers and enzymatic treatments on the baking quality of doughs formulated with five Canadian spring wheat cultivars.

For many years, the baking industry has been using chemical improvers as a way for compensating for flour quality variation due to growing conditions or wheat cultivar. However, the replacement of chemical dough improvers with natural ingredients or processing aids (i.e. enzymes) allows for the production of 'cleaner label' products. In the present research, dough and bread properties (mixing time, oven rise, loaf volume, crumb firmness and C-cell parameters) were analysed as a function of wheat cultivar (Glenn, Harvest, Lillian, CDC Plentiful and Stettler), additive-type (ascorbic acid, azodicarbonamide, glucose oxidase and fungal xylanase) and concentration. Overall, the cultivar Glenn appeared to have improved baking performance relative to the other cultivars, regardless of the additive and additive concentration. On the other hand, Stettler showed poorer baking quality and performance even with the addition of oxidizers and enzymes in relation to the control. The concentration of additive was found to have little or no effect on improving baking properties within each cultivar. Enzymes had similar or better performance than oxidizers in most cases.

Enzymatic cross-linking to improve the handling properties of dough prepared within a normal and reduced NaCl environment.

This research examines the use of three enzymes [glucose oxidase (GOX), hexose oxidase (HOX), and xylanase (XYL)] and their combinations [GOX-XYL and HOX-XYL] on the dough handling properties of CDC Plentiful and Stettler wheat cultivars prepared at reduced (1.0% wt. by flour) and normal (2.0% wt. by flour) NaCl levels. Properties investigated include dough rheology, stickiness, and ratio of resistance to extension and extensibility. The inclusion of XYL and its combinations with GOX and HOX increased the stickiness, yielded lower dough strength indicated by rheology, and reduced the ratio of resistance to extension and extensibility. The inclusion of oxidative enzymes yielded a stronger dough, where HOX addition to dough had the lowest stickiness values and highest |G*| values, whereas GOX addition led to the highest ratio of resistance to extension-extensibility. NaCl only had minor effects overall on dough strength and stickiness for the cultivars studied. Overall, superior dough handling properties were observed with oxidative enzyme addition (GOX and HOX) suggesting that the increased crosslinking that occurs could aid in improving low sodium bread dough properties.

Effect of salts from the lyotropic series on the handling properties of dough prepared from two hard red spring wheat cultivars of differing quality.

The influence of select salts from the lyotropic series (NH4Cl, KCl, NaCl, MgCl2, CaCl2, and MgSO4) on the rheology and stickiness of dough prepared from a strong (Pembina) and a weak (Harvest) hard red spring wheat flour were examined at a 1 and 2% salt levels, with water mobility and water association with different dough components also being assessed at the 1% salt level. Overall, Pembina was found to develop stronger gluten networks that were more resilient than those of Harvest as evident from a lower tan δ and less compliance during shear creep recovery rheology. However, the effect of salt-type differed based on cultivar. Pembina showed lower dough stickiness than Harvest in all cases. NH4Cl decreased dough stickiness the most for both cultivars. The use of alternative salts affected the association of water with the starch-fraction and gluten-fraction in doughs, and this effect was cultivar-dependent.

The effects of sodium reduction on the gas phase of bread doughs using synchrotron X-ray microtomography.

Globally, the bakery industry has a target of reducing sodium content in bread products. However, removing salt results in changes in the quality of bread through effects on dough's gas phase during the breadmaking process. Using synchrotron X-ray microtomography, the objective of this study was to investigate how sodium reduction induced changes in the gas phase parameters (i.e., gas volume fraction, bubble size distribution (BSD) and its time evolution) of non-yeasted doughs made from a wide range of formulations (i.e., wheat cultivar and water content) prepared with different mixing times. As salt content was reduced, a lower gas volume was retained in the dough by the end of mixing. Less gas bubbles were also retained if doughs were prepared from a stronger wheat cultivar, higher water content, and/or mixed for a shorter time. Rates of change in the median (R0) and the width (ε) of the fitted lognormal radius dependence of bubble volume fraction [BVF(R)] indicated that reduced sodium content permitted disproportionation to proceed more rapidly. Higher water content or longer mixing time also resulted in faster disproportionation, indicating that water content and mixing time can be manipulated as a means of increasing bubble stability against disproportionation during low-sodium breadmaking. An examination of relative changes in dough's gas phase parameters arising from sodium reduction demonstrated that wheat cultivar, water content and mixing time all affected dough's tolerance to sodium reduction. Therefore, attainment of good bread crumb cell structure in low-sodium bread formulas is a function of salt's effects on dough rheology in addition to its effect on yeast activity, so that dough formulation and mixing conditions also need to be considered.