Effect of particle size and temperature on rheological, thermal, and structural properties of pumpkin flour dispersion

Investigating potato flour processing methods and ratios for noodle production

A partial substitution of wheat flour with potato flour processed by various procedures was used to determine an optimal potato pretreatment method for noodle processing. Wheat flour was substituted with 10%, 30%, and 50% potato flour. Potato flour (PF) was processed using two different methods, including freeze-drying (FD) and low-temperature blanching, then oven drying (LTB_OD). The results showed that substituting wheat flour with freeze-dried (FD) flour (44.29 μm) significantly decreased the mean particle size of the blended flour, while LTB_OD flour (223.09 μm) increased the mean particle size. The pasting properties of wheat flour significantly improved when potato flour was added, with FD flour blends having the highest results. The highest dough development time (14.46 min) was attained when LTB_OD potato flour was substituted up to 50%. The microstructure images showed a poor and discontinuous gluten framework when potato flour content reached 50%. Adding potato flour decreased noodles' brightness (L*) while increasing their yellowness (b*). Noodles made from wheat and LTB_OD flour blends resulted in the highest cooking loss. The texture properties of noodles deteriorated when potato flour content reached 30%. Substituting up to 30% with freeze-dried flour and 10% LTB_OD resulted in noodles with the highest overall liking scores. The study suggests that for optimal noodle processing, substituting wheat flour with FD potato flour is more favorable than using LTB_OD, as it improves particle size, pasting properties, and overall liking scores while minimizing adverse effects on texture and cooking loss.

Enhancing vitamin D3 - iron blends via twin-screw dry granulation: Microstructural properties and cellular uptake analysis of vitamin D3

The aim of this study was to develop vitamin D3 (VD3) and iron (Fe) blended granules using Neusilin® US2 as an excipient. A central composite design of experiments was used for the continuous manufacturing process, considering VD3 and iron as independent variables and the bulk density, flow index, oil holding capacity, and color difference as response variables. The addition of VD3 had a significant effect on the powder flow properties. The X-ray diffraction and Scanning electron microscopy-energy dispersive X-ray analysis validated the presence of VD3 and Fe in the granules, whereas the variations in porosity and roughness were demonstrated by tomography and atomic force microscopy, respectively. The in vitro cellular uptake profile confirmed the absorption of VD3 in the breast cancer cell line MCF-7 with apparent apoptosis. These results could help in scaling up the process from laboratory to pilot scale in twin-screw granulation and boost the intervention of VitD3/iron deficiencies.

"Optimization and evaluation of quality characteristics of traditional Indian snack (baked balls) made by using pumpkin peel powder"

The baked balls (traditional Indian snack litti) were formulated along with the standardization and optimization of different ingredients and recipe. The optimization was done by using response surface methodology. Box behnken model was selected for the optimization in which wheat flour (40-80%), roasted bengal gram flour (10-50%), and pumpkin peel powder (2.5-15%) were selected as an independent factor for the standardization of baked balls recipe against the dependent factors including sensory attributes (colour and texture), moisture content and water activity. The proximate analysis of optimized baked balls resulted in energy, carbohydrate, protein, fat, dietary fibre, calcium, iron, and zinc value as 310 kcal, 55.6 g/100 g, 13.78 g/100 g, 2.73 g/100 g, 40.18 mg/100 g, 4.57 mg/100 g and 2.97 mg/100 g respectively. Additionally, carotenoid content of control and optimized baked balls was found to be 284 µg/100 g and 838.93 µg/100 g whereas the ascorbic acid content was observed as 1.84 mg/100 g and 5.82 mg/100 g respectively. It showed a significant increase in nutritional parameters when compared with control (wheat flour) baked balls. This study also evidenced that pumpkin peel powder can be used as a food supplement for various nutritional components.

Optimasi Formula Tepung Komposit Tinggi Protein dan Seng dengan Response Surface Methodology

Covid-19 pandemic had limited people’s movement despite the demand to remain productive and maintain good health. Therefore, it was necessary to provide foods which are easy to distribute, durable, nutritious, and easily transformable to increase immunity. This research aims to develop a composite flour (TK) formula with optimal proportion of wheat flour (TT), snakehead fish flour (TIG), pumpkin flour (TBuL), and pumpkin seed flour (TBiL) which then enriched with zinc. The resulting TK is expected to be used as an ingredient for nutritious snacks containing high protein and zinc. The research was conducted in four stages, namely the making of each constituent flour, determining the best formulation with the Response Surface Methodology using Central Composite Design model, characterizing the physicochemical properties of TK and making meatballs, biscuits, and unting-unting from the TK. The three products were tested on experimental animals for their metabolic responses. The optimization of the formula resulted in three optimal formulations, namely formula A, B, and C with the proportion of TT:TIG:TBuL:TBiL respectively as follows 55:20:15:10; 56.65:20:13.35:10; 57.98:20:12.02:10. The most optimal formula of composite flour was formula A with the highest protein (26.12%) and zinc (18.06 mg/kg) content among other formulas. Then, zinc was added into Formula A using microencapsulation, and TK with protein content of 26.74% and zinc of 56.8 mg/kg were obtained. The histopatology observation on experimental animals showed that the three products made from TK did not cause necrosis of the liver or cell infiltration in the kidneys.

Impact of Particle Size on the Rheological Properties and Amylolysis Kinetics of Ungelatinized Cassava Flour Suspensions

The effect of particle size on enzymatic hydrolysis of cassava flour at subgelatinization temperature was investigated. A multiscale physical metrology was developed to study the evolution of different physical-biochemical parameters: rheology, granulometry, and biochemistry. In this study, four fractions of cassava flour based on the particle sizes under 75 µm (CR075), 75–125 µm (CR125), 125–250 µm (CR250), and 250–500 µm (CR500) were screened for enzymatic hydrolysis effect. The results showed that all cassava flour suspensions exhibited a shear-thinning behavior, and the viscosity increased drastically with the increase of particle size. During hydrolysis, the viscosity reduced slightly and the non-Newtonian behavior became negligible beyond 4 h of the process. The particles size for CR075 and CR125 increased steadily in diameter mean. The samples of CR250 and CR500 showed more fluctuation by first decreasing, followed by increasing in particle sizes during the process. The highest hydrolysis yield was found for samples with particle size under 125 µm (89.5–90.7%), suggesting that mechanical treatment of cassava can enhance the bioconversion rate.

Stinging Nettles as Potential Food Additive: Effect of Drying Processes on Quality Characteristics of Leaf Powders

Stinging nettle (Urtica dioica L.) is a ubiquitous, multi-utility, and under-utilized crop with potential health benefits owing to its nutritional and bioactive components. The objective of the work is to produce powders by drying wild stinging nettle leaves as a storable, low-cost functional additive to be used in bakery and ready-to-cook products. Convective drying (CD) and freeze-drying (FD) were applied on unblanched (U) or blanched (B) leaves, which were then milled to nettle powders (NPs). The obtained NPs were evaluated for selected physicochemical (moisture, color), techno-functional (flow indices, hygroscopicity), and phytochemical (pigments, phenols) characteristics as well as mineral contents. Blanching improved mass transfer and reduced the oxidative degradation of pigments during drying, but it caused a loss of total phenols content, antioxidant activity, and potassium content. As for the drying method, CD resulted in better flow properties (i.e., Carr Index and Hausner Ratio), while FD retained better the color, pigments, magnesium content, phenolic, and antioxidant parameters. Overall, the evaluated processing methods resulted in different technological properties that can allow for better evaluation of NPs as a food additive or ingredient. Among the NPs, blanched and freeze-dried powders despite showing inferior technological properties can be recommended as more suitable ingredients targeted f or food enrichment owing to better retention of bio-active components.

Insights into the Thermo-Mechanical Treatment of Brewers' Spent Grain as a Potential Filler for Polymer Composites

This paper investigated the impact of twin-screw extrusion parameters on the properties of brewers’ spent grain. The chemical structure, antioxidant activity, particle size, and color properties, as well as the emission of volatile organic compounds during extrusion, were investigated. The main compounds detected in the air during modifications were terpenes and terpenoids, such as α-pinene, camphene, 3-carene, limonene, or terpinene. They could be considered as a potential threat to human health and the environment. Changes in the chemical structure, antioxidant activity, and color of materials after modification indicated the Maillard reactions during extrusion, which resulted in the generation of melanoidins, especially at higher temperatures. This should be considered an exciting feature of this treatment method because modified brewers’ spent grain may improve the thermooxidative stability of polymer materials. Moreover, the impact of the brewers’ spent grain particle size on color and browning index used to determine the melanoidins content was investigated. The presented results show that proper adjustment of extrusion parameters enables the preparation of brewers’ spent grain with the desired appearance and chemical properties, which could maximize the efficiency of the modification process.

Manufacturing of Lightweight Aggregates as an Auspicious Method of Sewage Sludge Utilization

Sewage sludge is a high-volume and low-cost waste commonly generated worldwide, so its utilization is a vital issue. The application of this waste in the manufacturing of lightweight aggregates was investigated. The process was performed using intensive mixers with volumes of 5 and 30 L, as well as the industrial 500 L mixer. Then, granulates were sintered in a tube furnace. The influence of composition and mixer size on the particle size, microstructure, mechanical performance, and stability of lightweight aggregates in different environments was analyzed. The best results were obtained for a 500 L mixer, enhancing the industrial potential of the presented process. Increasing the share of sewage sludge in the composition of aggregates enhanced their porosity and reduced the specific weight, which caused a drop in compressive strength. Nevertheless, for all analyzed materials, the mechanical performance was superior compared to many commercial products. Therefore, sewage sludge can be efficiently applied as a raw material for the manufacturing of lightweight aggregates. The presented results confirm that a proper adjustment of composition allows easy the tailoring of aggregates' performance and cost.

Physicochemical, functional and rheological properties of grass pea (Lathyrus sativus L.) flour as influenced by particle size

Different properties of grass pea (Lathyrus sativus L.) flour passed through 60, 72, 85, 100, 150 and 200 mesh sieves and in the size range of 249-74 μm were studied. The protein content reduced while fat content improved significantly with diminution in particle size. Flowability, capacities to absorb water and form foam as well as stability of foam decreased while increase in swelling capacity, swelling index, oil absorption capacity was observed with decrease in flour particle size. Bimodal curve patterns were obtained for coarse flour samples of 249 μm and 211 μm using light scattering analysis. Scanning electron microscopy analysis revealed that starch granules were of variable shape embedded in protein and fibre matrix. The flour with fine particle size exhibited greater values for peak, final, break down and set back viscosities and the dough from fine particles showed highest values for storage modulus (G′), loss modulus (G″),|G^∗| and |η^∗|.

Effect of particle size, concentration, temperature and pH on rheological properties of shallots flour

Shallot flour was prepared and sieved into three different particle sizes of < 180 μm (sample A), 180 μm (sample B) and 250 μm (sample C). Effect of concentration [0.5%, 1.0%, 1.5% and 2.0% (w/w)], temperature (20, 30, 40, 60 and 80 °C), pH (4, 7 and 10) and freezing (- 20 °C) on rheological properties of shallot flour were studied at increasing shear of 0.1-100 s^-1. Effect of dynamic change in temperature (15-95 °C) was also measured at constant shear rate of 50 s^-1. Power law (Eq. 2) model with coefficient of determination (R²) above 0.90, well described the rheological behavior of the shallot flour as a shear thinning, non-Newtonian fluid at different concentration, temperature and pH. All the samples had n values below 1 and increase in viscosity or consistency index (k) value with increase in concentration of the sample was observed, while inverse relation was observed when temperature was increased. All samples showed increase in k value when the pH of the dispersion was varied from acidic to alkaline condition. Viscosity of samples were found unaffected even after freezing in freeze-thaw cycle. These data show sample A to be most suitable for their application as thickener, having highest k value. The obtained research provides information for utilization of shallot as a thickener in various food industries.

Effects of granule size on physicochemical and digestive properties of potato powder

BACKGROUND

Potato powder, a rich source of high-quality protein and starch, plays an important role in the production of functional foods. In this study, ball-mill processed potato powders with different particle sizes (278, 208, 129, and 62 μm) were analyzed in terms of physicochemical, pasting, rheological, and digestive properties.

RESULTS

Scanning electron microscopy and laser diffraction analysis of the samples revealed mono-model particle-size distributions. X-ray diffraction analysis confirmed structure destruction of starch pellets. Proximate composition and physical property analysis showed an increase in the water, ash, protein, and starch content. Meanwhile, the water solubility index and swelling power values were found to increase with decreasing grain size, and so were the brightness (L*) and redness (b*) values of the potato powders. With particle size reduced to 129 μm, large changes were observed in gelatinization properties, such as peak viscosity, trough viscosity, breakdown viscosity, and final viscosity. Oscillatory rheology results also showed that, with the decrease in particle size, the storage modulus (G') and loss modulus (G″) improved, with highest storage modulus (G') observed in the 129 μm particle size. The hydrolysis rate and glycemic index also increased in the 129 μm potato powder.

CONCLUSION

The results provide information that could be useful for improving quality characteristics by using specific grain sizes in the development of potato-based products such as gluten-free products and ethnic food products with particular functional and rheological properties. © 2020 Society of Chemical Industry.

Nutritional Value and Modelling of Carotenoids Extraction from Pumpkin (Cucurbita Moschata) Peel Flour By-Product

By-products from fruits and vegetables are slices and peels that have been removed or rejected by the food industry and are considered to have low commercial value. Pumpkin peel is a source of carotenoids, minerals, antioxidants and phenolic compounds. This work studied the nutritional value of pumpkin peel flours produced by convective drying (40 °C) and milling. Pumpkin peel flours contained high contents of insoluble fibres (24.46 g/100 g), potassium (19.1 g/kg) and iron (152.5 mg/kg). Carotenoids were extracted using hexane at 40 °C, and flour particles were classified by 35-, 80- and 100-mesh sieves. The total carotenoids content ranged from 216.9 to 306.8 μg/g. Fick’s second law model computed that 215 min was required to extract 99 % of the total carotenoids. This work evidenced the effects of particle size on carotenoids extraction efficiency and demonstrated that pumpkin by-product flour could be used as a food ingredient or natural dye.

Functional Properties of Glutinous Rice Flour by Dry-Heat Treatment

Glutinous rice flour (GRF) and glutinous rice starch (GRS) were modified by dry-heat treatment and their rheological, thermal properties and freeze-thaw stability were evaluated. Compared with the native GRF and GRS, the water-holding ability of modified GRF and GRS were enhanced. Both the onset and peak temperatures of the modified samples increased while the endothermic enthalpy change decreased significantly (p < 0.05). Meanwhile, dry heating remarkably increased the apparent viscosities of both GRF and GRS. Importantly, compared with GRS samples, the storage modulus (G') and loss modulus (G") values of modified GRF increased more greatly and the tanδ values decreased more remarkably, indicating that the dry-heat treatment showed more impact on the GRF and a higher viscoelasticity compared with GRS. Our results suggest the dry-heat treatment of GRF is a more effective method than that of GRS, which omits the complex and tedious process for purifying GRS, and thereby has more practical applications in the food industry.

Effects of particle size distribution on some physical, chemical and functional properties of unripe banana flour

The objective of this study was to examine the effect of particle size distribution on physical, chemical and functional properties of unripe banana flour for the first time. A pure triploid (AAA group) of Musa acuminata subgroup Cavendish (°Brix;0.2, pH;4.73, titratable acidity; 0.56g/100g malic acid, total solids; 27.42%) which was supplied from Gazipaşa, Antalya, Turkey from October 2014 to October 2015 was used. Size fractions of <212, 212-315, 316-500 and 501-700μm were characterized for their physical, functional and antioxidant properties. Particle size significantly effected color, water absorbtion index and wettability. L(∗) value decreased, a(∗) and b(∗) values decreased by increasing particle size (r(2)=-0.94, r(2)=0.72, r(2)=0.73 respectively). Particles under 212μm had the lowest rate of wettability (83.40s). A negative correlation between particle size and wettability (r(2)=-0.75) and positive correlation between particle size and water absorption index (r(2)=0.94) was observed.

A Review of Drying Processes in the Production of Pumpkin Powder

Pumpkin is widely used as a valuable food source and is gaining the attention of healthcare consumers. Dried powdering pumpkin is an alternative way to increase the consumption. For these reasons, a sound knowledge of the processes for drying and powdering of pumpkin is needed. Therefore, the present review summarizes data from the literature and points out promising areas for further research. This review focused mainly on various processes of dried pumpkin powder, including pre-treatment techniques which can influence the quality of dried product. Impacts of drying and storage methods on quality changes were also revealed in dried pumpkin powder such as the loss of color, changes in texture or an off-flavor and decreases in carotenoids or other nutrients. Moreover, this review also collected the basic information about characterization of pumpkin fruit and also chemical characteristics and nutritional values of pumpkin. Finally, the review pointed out areas for future research to further elucidate the best methods of dried pumpkin powdering for the local companies.