DON reduction of wheat grain without compromising the lab-scale milling properties of flour

Wheat bran was investigated to be the most commonly contaminated raw material by mycotoxins. However, there are no economical and practical pretreatment methods for industrial on-line application until now. The effect of light debranning on deoxynivalenol (DON) removal, polyphenol oxidase (PPO) activity and flour quality from lab-scale milling were performed. For on-line production, the DON concentration in wheat decreased 15.89% at debranning ratio of 1.2%. For lab experiment, the maximum DON removal for wheat and flour was 23.35% and 21.95%, respectively. However, the PPO activity, browning of dough sheet and flour qualities in lab scale exhibited no significant variation. Light debranning (1.2%) prior to milling could be efficiently applied to on-line wheat production

Minimizing water consumption for biofuel and bioproduct conversion from lignocellulosic biomass

Doctor of PhilosophyDepartment of Biological & Agricultural EngineeringDonghai WangGlobal demand for renewable biofuels and biochemicals has been promoting the development of biomass valorization technologies. However, the efforts have not led to its commercial realization. To unlock the recalcitrant biomass, pretreatment is an inevitably critical step. Unfortunately, excessive water washing of the pretreated biomass with wastewater discarding significantly causes water overconsumption and chemicals loss. The goal of this research was to minimize water consumption for biofuel and bioproduct conversion from biomass in an economically viable manner. The first chapter aimed to answer three prevalent questions: (i) why is excessive water washing needed after biomass pretreatment? (ii) is the higher solid loading used for pretreatment, hydrolysis, and fermentation better? (iii) why are most of the proposed economically viable biorefineries still not commercialized? Regarding the reduction in water consumption and enhancement of sugar and ethanol concentrations, physicochemical and biological detoxification, black liquor recycling, fed-batch model, strain genetic engineering, and ethanol (first and second generations) integration approaches were critically discussed in terms of strengths and weaknesses. Collectively, biomass-to-ethanol commercialization necessitates a comprehensive understanding of economic, environmental, and policy perspectives. Technoeconomic analysis as an essential valuation for potential commercialization from laboratory scale is recommended, and it should be relaying on accurate experimental data rather than an overrated empirical assessment. The second chapter evaluated the potential of acetic acid (HOAc)-sodium hydroxide (NaOH) integrated pretreatment of biomass to reduce water and chemicals consumption. Pretreatment effectiveness including morphology, crystallinity, and component recovery was elucidated. Results showed that HOAc and NaOH in the mixed filtrate were neutralized to achieve a pH of around 4.80 resulting in the alkali lignin precipitation. Lignin (46.01 and 48.38 g/kg-biomass for hemp and poplar, respectively) exhibiting comparable Fourier transform infrared spectroscopy (FTIR) characteristics with the commercial alkali lignin was recovered. Compared to sodium acetate buffer as a control, integrating HOAc and NaOH pretreated biomass and their mixed filtrate for enzymatic hydrolysis boosted total sugar concentration (hemp: 42.90 vs. 38.27 g/L; poplar: 43.18 vs. 38.76 g/L) without compromising glucose yield (hemp: 70.86 vs. 70.69%; poplar: 66.48 vs. 69.48 %) but improving xylose yield (hemp: 60.10 vs. 35.92%; poplar: 56.90 vs. 29.39 %). The third chapter revealed the effects of post-washing [one-volume water (I-VW) or double-volume water (Ⅱ-VW)] on pretreated biomass and enzymatic hydrolysis. Compared to I-VW, Ⅱ-VW increased 3.76-6.80% of glucan content in NaOH pretreated biomass, diminished lignin recondensation, and heightened cellulose-related FTIR peak intensities, crystallinity index, and lignin removal. The pH of the mixed filtrate was around 4.80, precipitating the NaOH soluble lignin partially. Although Ⅱ-VW had lower lignin recoveries than I-VW, their FTIR characteristics were equivalent to the commercial alkali lignin. Enzymatic hydrolysis at solid loadings of 2.5-10% (w/v) demonstrated that I-VW and Ⅱ-VW had marginal variations in sugar concentration and conversion efficiency, indicating that I-VW is sufficient for post-washing pretreated biomass. Glucose concentration exhibited a quadratic correlation with solid loading and hemp biomass reached the maximum glucose (43.88 g/L) and total sugar (57.08 g/L) concentrations with I-VW. The fourth chapter validated the potential of HOAc-NaOH integrated pretreatment for glucose, xylose, 5-hydroxymethylfurfural (HMF), furfural, and lignin production of four genotypes of industrial hemp biomass that were harvested from Haysville and Manhattan, KS. The integration process effectively rendered the pH of the integrated filtrate and slurry to approximately 4.80. The highest lignin recovery of 73.13 g/kg biomass was achieved by Rigel from Manhattan. FTIR spectrum showed that only lignin derived from Vega (Haysville) and Anka (Manhattan) was comparable to the commercial alkali lignin. Retaining monosaccharides (2.24-3.81 g/L) enhanced sugar concentrations (glucose: 40.40-45.71 g/L; xylose: 7.09-8.88 g/L) and conversion efficiencies (glucose: 71.19-77.71%; xylose: 45.42-52.03%). Besides, 0.79-1.25 g/L of HMF and 0.99-1.59 g/L of furfural coupling with 1.96-2.95% and 10.00-14.65% conversion efficiencies, respectively, were obtained in the final hydrolysate. The fifth chapter performed three pretreatment scenarios (I: H2SO4 pretreatment with NaOH neutralization; II: NaOH pretreatment with H2SO4 neutralization; and III: parallel H2SO4 and NaOH pretreatments following their integration) with enzymatic hydrolysis for glucose, xylose, HMF, furfural, bioethanol production at high solid (15 and 25%, w/v) loading without solid-liquid separation and further detoxification. With an initial solid loading of 25% (w/v), scenario I reached the highest furfural (4.94 g/L) and HMF (2.82 g/L) concentrations, scenario II achieved the highest glucose (73.25%) and xylose (77.49%) yields, while scenario III displayed the highest sugar concentration (74.53 g/L). Only the hydrolysate from NaOH pretreatment and enzymatic hydrolysis with 10% initial solid loading can be efficiently fermented to ethanol (17.92 g/L) by the traditional yeast. In summary, integrating acid and alkali pretreatment of biomass has great potential to reduce water consumption for multi-stream biofuel and bioproduct production. There is a lot of room for further research on upgrading sugar and lignin to high-value chemicals

Production of biscuits by substitution with different ratios of yellow pea flour

To promote the commercialization of yellow pea flour (YPF) due to its nutritional benefits. Four biscuits with different YPF ratio (10%–50%) were conducted to explore the optimal addition percentage. The effects of YPF on the rheological and baking performance of biscuits were performed. The results showed that the substitution ratio of YPF and milling methods had a critical impact on the rheological properties of dough. The dough stability decreased gradually while a softening degree increased with YPF ratio increased. In a term of biscuits, the dimensions of length (L), width (W), thickness (T) and color (L*) of biscuits reduced as YPF addition ratio increased, while colors (a* and b*) and hardness apparently increased. In addition, milling methods had a great influence on the texture and sensory evaluation of four biscuits. The dimensions and color parameters of biscuits from fine flours were larger than that from coarse flours, whereas hardness from fine flours was relatively softer, indicating flour with fine particle size could accelerate the extension and expansion of dough network, and improve Maillard reaction during baking. The highest sensory score for short and tough biscuits was obtained given at YPF ratio of 30% without compromising the qualities of biscuits

Effect of Different Debranning Degrees on the Qualities of Whole Wheat Flour and Chinese Steamed Bread

Abstract: Strong gluten, middle-strong gluten and middle gluten wheat were used as raw materials to obtain whole wheat flour by dry debranning process, and the effect of different debranning degrees on the quality of wheat kernel, whole wheat flour and Chinese steamed bread was evaluated. The results showed that the ash content, hardness index and thousand kernel weight of wheat kernels were decreased with increasing debranning degree by 0.17%, 1.0–1.5 and 1.74–1.82 g, respectively, whereas the volume weight was increased by 22.0–23.4 g/L. The contents of ash and damaged starch in whole wheat flour were decreased by 0.12%–0.14% and 1.0–2.1 UCDc, respectively; insoluble dietary fiber and total dietary fiber were decreased by 0.38%–0.49% and 0.13%–0.17%, respectively, while soluble dietary fiber was increased by 0.22%–0.33% with increasing debranning degree. Besides, the pasting properties of whole wheat flour were increased with increasing debranning degree, the stability time was prolonged by 0.3–0.7 min, and the degree of softening was decreased by 9–25 FU. The hardness, gumminess and chewiness of steamed bread were decreased by 732–1 114 g, 335–549, and 147–346 respectively, and the springiness and resilience were increased by 0.030–0.031, and 0.049–0.066, respectively. At the same time, the overall sensory score and L* value of steamed bread were increased, indicating that debranning treatment can significantly improve the rheological properties of whole wheat flour, and efficiently improve the quality of steamed bread

Lignin, sugar, and furan production of industrial hemp biomass via an integrated process

Traditional pretreatment of lignocellulosic biomass is often accompanied by washing and disposal of wastewater, which leads to overuse of water and loss of by-products. The objectives of this study were to validate the potential of an acid-base integrated process for simultaneous sugars, furans, and lignin production without washing and wastewater discarding. The difference in conversion performance among different biomass resources was also demonstrated. Parallel acetic acid (HOAc, pH = 2.25) and sodium hydroxide (NaOH, pH = 13.46) pretreatments followed by solid and liquid integration were applied to four genotypes of industrial hemp (Cannabis sativa L.) biomass that were harvested from two planting locations (Haysville and Manhattan, KS). Results showed that genotype, planting location, and their interaction had notable influences on biomass composition and its conversion to bioproducts but exhibited different trends. Glucan content of biomass from Haysville, ranging from 47.29 to 50.05%, were higher than those of 42.49–48.38 % from Manhattan with the lowest being Vega (Manhattan) and the highest being Hlukouskii (Haysville). Xylan and lignin contents in all the hemp genotypes were 11.70–13.88 % and 10.45–15.14 %, respectively. The integration process effectively rendered the pH of the integrated filtrate and slurry to approximately 4.80. The highest lignin recovery of 73.13 g/kg biomass was achieved by Rigel from Manhattan. Fourier transform infrared spectroscopy (FTIR) characterization showed that only lignin derived from Vega (Haysville) and Anka (Manhattan) was comparable to the commercial alkali lignin. Retaining monosaccharides (2.24–3.81 g/L) enhanced sugar concentrations (glucose: 40.40–45.71 g/L; xylose: 7.09–8.88 g/L) and conversion efficiencies (glucose: 71.19–77.71 %; xylose: 45.42–52.03 %). Besides, furans including 0.79–1.25 g/L of hydroxymethylfurfural (HMF) and 0.99–1.59 g/L of furfural coupling with 1.96–2.95 % and 10.00–14.65 % conversion efficiencies, respectively, were obtained in the final hydrolysate. Biomass from Haysville produced relatively higher glucose concentrations than those from Manhattan. Based on mass balance, the most productive genotype was Rigel. This study offers essential information to reduce water and chemical overconsumption and to understand the effects of genotype and planting location on biomass valorization

Analysis of temperature field for a surface-mounted and interior permanent magnet synchronous motor adopting magnetic-thermal coupling method

Aiming at obtaining high power density of surface-mounted and interior permanent magnet synchronous motor (SIPMSM), it is important to accurately calculate the temperature field distribution of SIPMSM, and a magnetic-thermal coupling method is proposed. The magnetic-thermal coupling mechanism is analyzed. The thermal network model and finite element model are built by this method, respectively. The effects of power frequency on iron losses and temperature fields are analyzed by the magnetic-thermal coupling finite element model under the condition of rated load, and the relationship between the load and temperature field is researched under the condition of the synchronous speed. In addition, the equivalent thermal network model is used to verify the magnetic-thermal coupling method. Then the temperatures of various nodes are obtained. The results show that there are advantages in both computational efficiency and accuracy for the proposed coupling method, which can be applied to other permanent magnet motors with complex structures

The characteristics analysis and cogging torque optimization of a surface-interior permanent magnet synchronous motor

This paper proposes optimal stator skewed slot analytical method for cogging torque reduction in surface-interior permanent magnet synchronous motor(SIPMSM) and analyzes the characteristics of SIPMSM. The series-parallel equivalent magnetic circuit models(EMCMs) of SIPMSM is built based on the characteristics of magnetic circuits, which is used to design the basic electromagnetic parameters of SIPMSM. Analytical expressions of cogging torque are derived from applying analytical techniques. Stator skewed slot for cogging torque minimum is adopted, and the stator skewed slot pitch is confirmed based on the analytical expressions of the resultant cogging torque. The cogging torque, torque ripple, back electromotive force(back-EMF), power-angle characteristics, efficiency and power factor of SIPMSM are analyzed by establishing 3-dimensional finite element model(3-D-FED) of SIPMSM with stator skewed slot and straight slot. It is shown that the comprehensive performance of optimized SIPMSM is improved as confirmed by finite element analysis and analytical calculation results

Elucidating thermochemical pretreatment effectiveness of different particle-size switchgrass for cellulosic ethanol production

Effects of switchgrass particle sizes (\u3c0.25 mm, 0.5–1.0 mm, and 2.0–4.0 mm) on the effectiveness of H2SO4 and NaOH pretreatments were investigated. As particle size increased, glucan, xylan, and lignin contents in raw switchgrass augmented from 30.32% to 32.02%, 18.44% to 19.03%, and 14.78% to 15.33%, respectively. Glucan and xylan (58.54–60.94% and 18.55–20.01%) contents in NaOH pretreated switchgrass and their recoveries (91.95–94.69% and 47.91–52.31%) increased. The highest glucan content (55.76%) and recovery (79.72%) in H2SO4 pretreated switchgrass were reached by middle particle size. The lowest (59.39% for H2SO4 and 58.99% for NaOH) and highest (65.23% for H2SO4 and 66.15% for NaOH) CrI values were obtained from middle and small particle sizes, respectively. SEM images and FTIR spectra showed no visible variations in microstructures and chemical bonds among different particle sizes under the same pretreatment conditions. On the basis of pretreated switchgrass, the highest ethanol concentration and efficiency were reached by big particle size for H2SO4 pretreated (7.03 g/L and 49.28%) switchgrass, while they were achieved by small particle size for NaOH pretreated (11.68 g/L and 72.37%) switchgrass. The highest ethanol yield based on raw switchgrass was attained by big particle size for untreated (29.54%), middle particle size for H2SO4 pretreated (30.60%), and small particle size for NaOH pretreated (62.36%) switchgrass. These findings indicate that the optimal ethanol conversion performance is the result of the interaction between the pretreatment method and biomass particle size

Bioconversion of industrial hemp biomass for bioethanol production: A review

Industrial hemp (Cannabis sativa L.) with robust drought-resistant features has excellent agronomic and pharmaceutical characteristics. As the federal prohibition on hemp cultivation was lifted, its valorization in various aspects is highly required. This review aims to summarize the potential of hemp biomass for bioethanol production. Chemical compositions of hemp biomass were evaluated as compared with those of corn fiber, corn stover, and sorghum bagasse. Several representative pretreatment technologies used for hemp biomass were summarized in terms of sugar recoveries, lignin removal, and sugar and ethanol yields. This review presents numerous technical barriers attributed to insufficient fermentable sugar and ethanol concentration during the conversion processes. Also, innovative research approaches (pretreatment optimization, co-fermentation of hexose and pentose, increasing potential sugar loading) in overcoming these challenges were critically reviewed. This review would promote future research on the utilization of hemp biomass for biofuel applications

Effect of pectin on properties of potato starch after dry heat treatment

Purpose: To evaluate the effect of pectin on the properties of potato starch after dry heat treatment. Methods: Rapid visco analyzer (RVA), differential scanning calorimetry (DSC), texture profile analyzer (TPA), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and x-ray diffractometry (XRD) were used to determine the properties of modified potato starch and pectin blends after dry heat treatment. Results: Results from RVA showed that the peak viscosity of modified potato starch decreased gradually with increase in pectin concentration, dry heat time and dry heat temperature, while starch breakdown decreased and setback was increased to varying degrees. The lowest breakdown was 792 cP at dry heat temperature of 140 °C. Modified potato starch had broader ranges of gelatinization temperatures and lower gelatinization enthalpy than raw potato starch. Dry heat treatment improved the hardness, gumminess and chewiness of the gels of modified potato starch and pectin blends SEM micrographs showed some cluster shapes in microstructure after dry heat treatment of starch-pectin blends. Infrared spectra revealed that pectin addition and dry heat treatment did not cause changes in starch structure. However, x-ray diffractograms indicated that dry heat treatment weakened the third peak of potato starch. Conclusion: These results indicate that dry heat treatment effectively alters the properties of potato starch and pectin blends. This finding broadens the applications of modified potato starch in food and pharmaceutical industries