Effect of sorghum flour properties on gluten-free sponge cake.

As the demand for gluten-free products increases, the use of sorghum flour becomes a good alternative. Sponge cakes are consumed worldwide and suitable for formulations that could replace wheat flour. One of the most influential parameters on sponge cake quality is the flour particle size. In this study, we obtained and characterized different flours by milling white and brown sorghum grains and evaluated the influence of flour characteristics on batter properties and gluten-free sponge cake quality. Flours were produced by pearling, milling and sifting; and were characterized for flour composition, particle size distribution, damaged starch and water absorption. The structure, density, and viscosity of the batters; and specific volume and crumb properties of the sponge cake were evaluated. The results showed that flour composition, and properties were modified by the milling processes. Pasting viscosity increased as the particle size of the flours was reduced. Brown or white sorghum flour with smaller particle size produced high density and viscosity batters with small and homogeneous air bubbles distribution. Independently of the sorghum variety used, smaller particle size flour leads to sponge cakes of high volume and low firmness. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05150-0.

Dissecting the biochemical architecture and morphological release pathways of the human platelet extracellular vesiculome.

Platelet extracellular vesicles (PEVs) have emerged as potential mediators in intercellular communication. PEVs exhibit several activities with pathophysiological importance and may serve as diagnostic biomarkers. Here, imaging and analytical techniques were employed to unveil morphological pathways of the release, structure, composition, and surface properties of PEVs derived from human platelets (PLTs) activated with the thrombin receptor activating peptide (TRAP). Based on extensive electron microscopy analysis, we propose four morphological pathways for PEVs release from TRAP-activated PLTs: (1) plasma membrane budding, (2) extrusion of multivesicular α-granules and cytoplasmic vacuoles, (3) plasma membrane blistering and (4) "pearling" of PLT pseudopodia. The PLT extracellular vesiculome encompasses ectosomes, exosomes, free mitochondria, mitochondria-containing vesicles, "podiasomes" and PLT "ghosts". Interestingly, a flow cytometry showed a population of TOM20+LC3+ PEVs, likely products of platelet mitophagy. We found that lipidomic and proteomic profiles were different between the small PEV (S-PEVs; mean diameter 103 nm) and the large vesicle (L-PEVs; mean diameter 350 nm) fractions separated by differential centrifugation. In addition, the majority of PEVs released by activated PLTs was composed of S-PEVs which have markedly higher thrombin generation activity per unit of PEV surface area compared to L-PEVs, and contribute approximately 60% of the PLT vesiculome procoagulant potency.

Modeling and optimization of finger millet pearling process by using RSM.

Finger millet pearling process involves so many drudgery prone operations that specify the need for the development of finger millet pearling drum. The performance of pearling drum depends on its operational parameters. Therefore, this study aims to optimize the operational parameters of the pearling drum such as drum speed, concave clearance and pearling sieve size to obtain maximum pearling efficiency and minimum grain damage. The analysis was carried out using Response Surface Method along with the Box-Behnken Design tool. The optimum operational parameters were found as drum speed 7.25 m/s, concave clearance 3 mm and pearling sieve size 2 mm that predicts the maximum pearling efficiency of 98.95% and minimum grain damage of 0.73%. Finally, the performance of the pearling drum was validated setting optimum conditions. It results pearling efficiency of 99% along with 0.5% grain damage. Above results indicates that the validated pearling drum performance was better than predicted.

Optimizing operational parameters of finger millet threshing drum using RSM.

The operational parameters of threshing drum play a dominant role in the design and development of the finger millet thresher-cum-pearler. The finger millet threshing drum was developed and effects of operational parameters such as feed rate, drum speed and concave clearance on threshing efficiency, pearling efficiency and grain damage were individually studied using response surface method. A statistical tool of the central composite rotatable design was used for analysis. It was found that the maximum threshing efficiency, maximum pearling efficiency and minimum grain damage were 98%, 85% and 0.086%, respectively at the feed rate 36 kg/h, drum peripheral speed 7.12 m/s and concave clearance 5 mm. The performance evaluation of the drum was validated by setting above condition in the threshing drum. It was found that the maximum threshing efficiency 99% against predicted 98%, maximum pearling efficiency 86% against predicted 85% and 0.1% grain damage was found against predicted 0.086%.

Losses of nutrients and anti-nutrients in red and white sorghum cultivars after decorticating in optimised conditions.

The aims were to optimise pearling process of red and white sorghum by assessing the effects of pearling time and grain moisture on endosperm yield and flour ash content and to assess nutrient and anti-nutrient losses produced by pearling different cultivars in optimised conditions. Both variables significantly affected both responses. Losses of ashes (58%), proteins (9.5%), lipids (54.5%), Na (37%), Mg (48.5%) and phenolic compounds (43%) were similar among red and white hybrids. However, losses of P (30% vs. 51%), phytic acid (47% vs. 66%), Fe (22% vs. 55%), Zn (32% vs. 62%), Ca (60% vs. 66%), K (46% vs. 61%) and Cu (51% vs. 71%) were lower for red than white sorghum due to different degree of extraction and distribution of components in the grain. Optimised pearling conditions were extrapolated to other hybrids, indicating these criteria could be applied at industrial level to obtain refined flours with proper quality and good endosperm yields.

Quinoa bitterness: causes and solutions for improving product acceptability.

Awareness of the several agronomic, environmental, and health benefits of quinoa has led to a constant increase in its production and consumption not only in South America, where it is a native crop, but also in Europe and the USA. However, producing wheat or gluten-free based products enriched with quinoa alters some quality characteristics, including sensory acceptance. Several anti-nutritional factors such as saponins are concentrated in the grain pericarp. These bitter and astringent substances may interfere with the digestion and absorption of various nutrients. Developing processes to decrease or modify the bitterness of quinoa can enhance palatability, and thus consumption, of quinoa. In addition to the production of sweet varieties of quinoa, other processes have been proposed. Some of them (i.e. washing, pearling and the combination of the two) have a direct effect on saponins, either by solubilization and/or the mechanical removal of seed layers. Others, such as fermentation or germination, are able to mask the bitterness with aroma compounds and/or sugar formation. This review presents the major sources of the undesirable sensory attributes of quinoa, including bitterness, and various ways of counteracting the negative characteristics of quinoa. © 2018 Society of Chemical Industry.

Improving functional and nutritional profiles of barley flours with diverse starch types through pearling.

A comparative analysis of chemical, functional, and digestive parameters was conducted on five new barley genotypes designed for food purposes, differing in starch type, ß-glucans, and arabinoxylan content. Both whole and pearled grain flours were examined. Amylose exhibited positive correlations with least gelation capacity (r = 0.60), gelation temperature (r = 0.90), and resistant starch (r = 0.80). Waxy varieties showed greater water-holding capacity, viscosity, and rapid digestibility compared to normal and high-amylose varieties. Pearling (10%) decreased arabinoxylans by 48% and proteins by 7%, while increasing ß-glucans by 8% and starch by 13%. Additionally, pearling improved viscosity and hydration parameters across varieties. This allowed normal and high-amylose genotypes to enhance their functional properties and nutritional value through increased ß-glucan and resistant starch content. This exploration advances the understanding of barley's functional attributes for food industry and underscores the potential of pearling to augment consumer nutritional value and health-promoting properties.

A Case Report on "Pearling": Removal of Infected Objects During Circumcision.

The insertion of foreign bodies underneath the skin of the penis is commonly referred to as "pearling." Although rare, there are case reports that describe acute complications such as infection and damage to surrounding penile neurovascular structures; however, there is a paucity of data describing long-term complications and surgical management of such cases. A 43-year-old male presented with a penile abscess secondary to "pearling" five years after insertion. His abscess was drained and selected foreign objects were subsequently removed during a simultaneous circumcision procedure. This report describes a case in which surgical removal of penile foreign bodies was performed during a circumcision without the need for additional incisions. The case is unique in that it details a complication five years after initial insertion with microbiological data to guide adequate treatment.

Effect of pearling on nutritional value of highland barley flour and processing characteristics of noodles.

Highland barley is increasingly recognized as its nutritional benefits but its structure restricts the development and utilization in the food industry. The quality of highland barley products may be impacted by pearling, an essential step before the hull bran is consumed or further processed. The nutrition, function and edible qualities of three highland barley flour (HBF) with different pearling rates were assessed in this study. The content of resistant starch was the highest when the pearling rate of QB27 and BHB was 4%, while 8% of QB13. Un-pearled HBF showed higher DPPH, ABTS and superoxide radicals inhibition rates. The break rates of QB13, QB27 and BHB obviously decreased from 51.7%, 53.3% and 38.3% to 35.0%, 15.0% and 6.7% respectively at 12% pearling rate. PLS-DA model further attributed the improvement of pearling on noodles quality to the alteration of resilience, hardness, tension distance, breaking rate and water absorption of noodles.

Design of Cereal Products Naturally Enriched in Folate from Barley Pearling By-Products.

Folate is a fundamental vitamin for human health in prevention of many diseases; however, unfortunately its deficiency is widespread, so a greater availability of folate rich foods is desirable. The aim of this study was to design new cereal products naturally enriched in folate using barley flour from pearling as ingredient. Folate content of unfortified and fortified commercial grain-based products was considered to identify the best ingredients for new formulation and for folate content comparisons. Nineteen Italian barley cultivars were evaluated for their folate content and Natura was chosen for its highest folate levels = 69.3 µg/100 g f.w. Application of pearling gave a by-product flour with a high folate level: 221.7 ± 7.0 µg/100 g; this flour was employed to design pasta and biscuits naturally enriched in folate: 87.1 µg/100 g and 70.1 ± 3.7 µg/100 g f.w., respectively. Folate content of new products is higher than commercial samples: 39.2 µg/100 g in refined pasta, 60.4 µg/100 g in wholemeal pasta, 62.1 µg/100 g in fortified biscuits and 10.4 µg/100 g in unfortified ones. Enriched pasta had higher folate retention (68.5%) after cooking compared to the fortified one (27.8%). This research shows promising results concerning the pearling technique to design new cereal products naturally enriched in folates.

From reversible to irreversible: When the membrane nanotube pearling is coupled with phase separation.

Membrane nanotubes, which are ubiquitous in biology and act as channels maintaining transport between different cells and organelles, readily undergo pearling in response to external stimuli. Membrane nanotube pearling involves generation of heterogeneous curvature coupled with redistribution of membrane components that may interfere with the shape recovery of pearled nanotubes. However, the mechanism underlying such delicate process remains unclear and difficult to study at the molecular scale in vivo. By means of molecular dynamics simulation, here we investigate pearling of multi-component membrane nanotubes and reversibility through manipulating system temperature and osmotic pressure. With the equilibrium shape of membrane nanotubes controlled by the osmotic pressure, our results demonstrate that the process of membrane nanotube pearling can be reversible or irreversible, depending on the phase segregation state. For the pearled nanotube releasing high surface energy, different lipid components redistribute along the tube axial direction. Lipids with unsaturated tails prefer gathering at the high-curvature shrinking region, whereas the swelling region is constituted by saturated lipids forming the liquid-ordered phase of a higher bending rigidity. Such curvature sensitive phase segregation minimizes the system free energy by reducing both the membrane bending energy and line tension at the phase boundary. As such, the pearled nanotube fails to recover its shape upon retracting stimuli, suggesting irreversibility of the membrane nanotube pearling coupled with phase separation. Given importance of membrane nanotube pearling in various cellular activities, these results provide a new mechanism of controlling equilibrium shapes of membrane nanotubes in complex cellular environment.

Effect of pearling on composition, microstructure, water migration and cooking quality of highland barley (Hordeum vulgare var. Coeleste Linnaeus).

Highland barley (HB) has become popular due to its nutritional benefits, and pearling as a necessary process that could broaden its applications. The influence of pearling on the composition, microstructure, water migration and cooking characteristics of HB was investigated. With different degrees of pearling (DOPs), the levels of nutritious components except for starch and ß-glucan, decreased, and the ß-glucan content gradually increased and reached a plateau when the DOP was over 15%. Pearling can significantly shorten the cooking time by removing different tissues, and removal of the pericarp layer had significant influence by reducing the cooking time by 17 min (i.e., HB with DOP 5%). From the result of Peleg model fitting and low-field nuclear magnetic resonance spectroscopy, the saturated water absorption of HB did not differ for a DOP 5% and above, and cooking mainly increased the amount of moderately bound water and added small amount of bound water.

Development of Quinoa Value Chain to Improve Food and Nutritional Security in Rural Communities in Rehamna, Morocco: Lessons Learned and Perspectives.

Agricultural production in the Rehamna region, Morocco is limited with various challenges including drought and salinity. Introduction of climate resilient and rustic crops such as quinoa was an optimal solution to increase farmer's income and improve food security. This study summarizes results obtained from a research project aiming to develop quinoa value chain in Morocco. The study tackled several aspects including agronomic traits (yield and growth), transformation, quality (nutritional and antinutritional traits) and economic analysis and, finally, a strength-weaknesses-opportunities-threats analysis, lessons learned and development perspectives were presented. From an agronomic point of view, introduced new quinoa cultivars showed higher performance than locally cultivated seeds and, furthermore, the use of irrigation and organic amendment has tremendously improved seed yield by double and three times, respectively, compared to rainfed conditions. Nutritional analysis revealed that protein and phosphorus content remained stable after seed pearling while most of the micronutrients content decreased after seed pearling. However, saponins content was reduced by 68% using mechanical pearling compared to 57% using both traditional abrasion and washing. The economic analysis showed that production cost of quinoa seeds could be further decreased using mechanized intensive tools along with irrigation and organic amendment supply. This study revealed several lessons learned from the field experience and proposed several development actions for each value chain component that can be implemented within a national quinoa program.

Spontaneous extrusion of male genital pearling.

Pearling is a practice of inserting small beads beneath the skin of the genitalia. Patients generally underwent this practice believing that this would have made their penis bigger and able to better satisfy their partners during intercourse. Pearling can cause complications. We report a case of spontaneous extrusion of genital pearling exiting in a granuloma of the inner face of the foreskin.

How Does Mechanical Pearling Affect Quinoa Nutrients and Saponin Contents?

Agriculture is facing many challenges, such as climate change, drought, and salinity, which call for urgent interventions for fast adaptation and crop diversification. The introduction of high-value and stress tolerant crops such as quinoa would be a judicious solution to overcome constraints related to abiotic stress and to increase land productivity and farmers' incomes. The implementation of quinoa in Morocco has not been supported by a full valorization program to control the quality of quinoa seeds. The novelty of this work is to assess the pearling operation as an efficient method of saponins removal as well as the determination of total residual saponins. This study aimed to evaluate the effects of several pearling durations on nutrient and saponin content of quinoa seeds of three tested varieties (Puno, Titicaca, and ICBA-Q5). Five pearling durations were tested (0, 2, 4, 6, 7, and 8 min) using a locally manufactured pearling machine. The results indicated that a pearling duration of two minutes was enough to reduce total saponin content from 0.49% to 0.09% for Puno variety, from 0.37% to 0.07% for Titicaca variety, and from 0.57% to 0.1% for ICBA-Q5 variety. Our results showed that pearling slightly reduced protein, total fat, and moisture contents for all varieties except for Puno, where total fat content slightly increased with the pearling. Puno variety had the highest seed content in terms of protein and total fat; the ICBA-Q5 variety had the lowest. Titicaca had the highest bran content in terms of protein and total fat, ICBA-Q5 had the highest bran content in terms of ash and the lowest bran content in terms of protein and total fat, and Puno had the lowest bran content in terms of ash. Pearling had no significant effect on macronutrient contents in the processed seed, but it resulted in a very highly significant difference for most of them in the bran except for Mg and S. Regarding seed content in terms of micro-nutrients, statistical analysis showed significant differences between varieties in terms of Zn, Cu, and Mn contents, but no significant difference was recorded for Fe or B. Pearling had no significant effect on seed micronutrient contents. Therefore, to retain maximum nutritional content in the quinoa and maintain quinoa integrity, it is necessary to limit the pearling duration of quinoa to two minutes, which is enough to reduce saponin content below the Codex Standard threshold (0.12%).

Bioactive Compounds and Antioxidant Capacity in Pearling Fractions of Hulled, Partially Hull-Less and Hull-Less Food Barley Genotypes.

Three food barley genotypes differing in the presence or absence of husks were sequentially pearled and their fractions analyzed for ash, proteins, bioactive compounds and antioxidant capacity in order to identify potential functional food ingredients. Husks were high in ash, arabinoxylans, procyanidin B3, prodelphinidin B4 and p-coumaric, ferulic and diferulic bound acids, resulting in a high antioxidant capacity. The outermost layers provided a similar content of those bioactive compounds and antioxidant capacity that were high in husks, and also an elevated content of tocols, representing the most valuable source of bioactive compounds. Intermediate layers provided high protein content, ß-glucans, tocopherols and such phenolic compounds as catechins and bound hydroxybenzoic acid. The endosperm had very high ß-glucan content and relative high levels of catechins and hydroxybenzoic acid. Based on the spatial distribution of the bioactive compounds, the outermost 30% pearling fractions seem the best option to exploit the antioxidant capacity of barley to the full, whereas pearled grains supply ß-glucans enriched flours. Current regulations require elimination of inedible husks from human foods. However, due to their high content in bioactive compounds and antioxidant capacity, they should be considered as a valuable material, at least for animal feeds.

Bioactive Components and Antioxidant Activity Distribution in Pearling Fractions of Different Greek Barley Cultivars.

In this study, three pearling fractions, namely bran, dehulled grains and pearled grains, derived from fourteen hulled and one hull-less Greek barley cultivars (Hordeum vulgare L.), were analyzed for the protein, ash, ß-glucan, phenolic compounds and tocols contents. High variations appeared in the bioactive contents across the barley cultivars and fractions as well. The protein and ash contents decreased from the outer to the inner layers, whereas ß-glucans presented an inverse trend. The highest protein and ß-glucan contents were in the hull-less cultivar; however, one hulled cultivar (Sirios) exhibited similar ß-glucan content, while another (Constantinos) had even higher protein content. The results also revealed that functional compounds were mainly located in bran fraction. Similar trends were also noted for the antioxidant activity. Ferulic acid was the primary phenolic acid in all fractions, followed by sinapic and p-coumaric acids that were dominant in bound form. However, oligomeric flavonoids, such as prodelphinidin B3, catechin, and procyanidin B2, were more abundant in free form. Overall, this study highlights that different barley cultivars can provide pearling flour fractions of varying composition (nutrients and bioactives), which have the potential to serve as nutritionally valuable ingredients in formulations of cereal-based functional food products.

Parboiling of sorghum grains as a strategy to improve endosperm yield and mineral content of refined flours.

The aims were (i) to optimize the parboiling/decorticating process by assessing the effects of parboiling soaking temperature (60-80 ℃) and pearling time (4-6 min and 5.5-9.5 min for red and white sorghum) on endosperm yield and ash content, to obtain pregelatinized refined flours from parboiling sorghum (RF-PS) and (ii) to evaluate the final content of selected nutrients in RF-PS obtained in these optimal conditions. Endosperm yield decreased with the increase of pearling time, and a maximum around 70 ℃ soaking temperature was observed. Ash content decreased with increasing soaking temperature and pearling time. The optimal conditions of soaking temperature-pearling time were 73.3 ℃-4.8 min for red sorghum and 67.9 ℃-8.6 min for white sorghum, considering maximum endosperm yield and ash content lower than 0.65 g/100 g. In RF-PS obtained under optimal conditions, protein, lipid, Cu, and free polyphenols were higher in red sorghum than white sorghum (10.16 ± 0.62 vs. 9.42 ± 0.61 g/100 g, 0.89 ± 0.16 vs. 0.62 ± 0.11 g/100 g, 2.08 ± 0.21 vs. 1.88 ± 0.20 mg/kg, 79.51 ± 14.51 vs. 63.82 ± 4.33 mg/100 g). Fe, Zn, Ca, and Na were higher in white sorghum than red sorghum (20.61 ± 2.92 vs. 17.56 ± 0.98 mg/kg, 11.94 ± 0.84 vs. 9.58 ± 1.65 mg/kg, 87.45 ± 12.91 vs. 75.31 ± 12.57 mg/kg, 129.62 ± 9.03 vs. 102.69 ± 28.34 mg/kg). No difference was observed in the contents of ash, Mg, and K. It was possible to improve endosperm yield using a parboiling process prior to decortication. In addition, this process contributes to increase the mineral content in RF-PS.

The Pearling Transition Provides Evidence of Force-Driven Endosomal Tubulation during Salmonella Infection.

Bacterial pathogens exploit eukaryotic pathways for their own end. Upon ingestion, Salmonella enterica serovar Typhimurium passes through the stomach and then catalyzes its uptake across the intestinal epithelium. It survives and replicates in an acidic vacuole through the action of virulence factors secreted by a type three secretion system located on Salmonella pathogenicity island 2 (SPI-2). Two secreted effectors, SifA and SseJ, are sufficient for endosomal tubule formation, which modifies the vacuole and enables Salmonella to replicate within it. Two-color, superresolution imaging of the secreted virulence factor SseJ and tubulin revealed that SseJ formed clusters of conserved size at regular, periodic intervals in the host cytoplasm. Analysis of SseJ clustering indicated the presence of a pearling effect, which is a force-driven, osmotically sensitive process. The pearling transition is an instability driven by membranes under tension; it is induced by hypotonic or hypertonic buffer exchange and leads to the formation of beadlike structures of similar size and regular spacing. Reducing the osmolality of the fixation conditions using glutaraldehyde enabled visualization of continuous and intact tubules. Correlation analysis revealed that SseJ was colocalized with the motor protein kinesin. Tubulation of the endoplasmic reticulum is driven by microtubule motors, and in the present work, we describe how Salmonella has coopted the microtubule motor kinesin to drive the force-dependent process of endosomal tubulation. Thus, endosomal tubule formation is a force-driven process catalyzed by Salmonella virulence factors secreted into the host cytoplasm during infection.IMPORTANCE This study represents the first example of using two-color, superresolution imaging to analyze the secretion of Salmonella virulence factors as they are secreted from the SPI-2 type three secretion system. Previous studies imaged effectors that were overexpressed in the host cytoplasm. The present work reveals an unusual force-driven process, the pearling transition, which indicates that Salmonella-induced filaments are under force through the interactions of effector molecules with the motor protein kinesin. This work provides a caution by highlighting how fixation conditions can influence the images observed.

Rapid and Nondestructive Determination of Aleurone Content in Pearling Fractions of Barley by Near-Infrared (NIR) and Fluorescence Spectroscopies.

The aim of the present work was to develop and evaluate near-infrared (NIR) and fluorescence spectroscopies as rapid and potential online methods for determination of the amount of aleurone in pearling dust fractions of barley. Phytic acid was used as a marker for the aleurone layer. Different varieties of barley were pearled, and dust fractions were progressively taken out. Sample concentration of phytic acid varied in the range of 0.5-4.1 g/100 g, and highest concentrations were obtained in dust fractions for pearling degrees in the range of 15-25%. Regression models for phytic acid were developed with the same high correlations for NIR and fluorescence spectroscopies (R2 = 0.96) and prediction errors of ±0.16-0.18 g/100 g. The models performed well on a test set of pearling fractions from two other barley varieties. The techniques are rapid and nondestructive, which means that they can be used online in connection with industrial pearling systems.