Co-digestion of poultry manure and residues from enzymatic saccharification and dewatering of sugar beet pulp

This study investigates the co-digestion of poultry manure (PM) with sugar beet pulp residues (SBPR) obtained from saccharification and dewatering of sugar beet pulp. The laboratory-scale experiments were conducted under batch and semi-continuous conditions at mesophilic temperatures (35 °C). Batch tests gave specific biogas and methane yields of 590 dm³/kgVS_fed and 423 dm³CH₄/kgVS_fed, respectively for SBPR, whereas the corresponding values for PM were 434 dm³/kgVS_fed and 300 dm³CH₄/kgVS_fed. The co-digestion of PM with SBPR was found to increase biogas and methane yields compared to the manure alone. In semi-continuous reactor experiments, the highest methane yield of 346 dm³ CH₄/kgVS_fed was achieved for the mixture containing poultry manure with 50% SBPR (weight basis) and a solids retention time (SRT) of 20 days. However, when poultry manure was digested as a sole feedstock, the biogas production was inhibited by ammonia, whereas the co-digestion of PM with 25% SBPR was slightly affected by volatile fatty acids, which concentrations exceeded 4000 g/m³.     

Enzymatic synthesis of sugar esters and their potential as surface-active stabilizers of coconut milk emulsions

Sugar esters are compounds with surfactant properties (biosurfactants), i.e., capable of reducing the surface tension and promote the emulsification of immiscible liquids. On the other hand, as with all emulsions, coconut milk is not physically stable and is prone to phase separation. Therefore, the aim of this work was to evaluate the synthesis of fructose, sucrose and lactose esters from the corresponding sugars using Candida antarctica type B lipase immobilized in two different supports, namely acrylic resin and chitosan, and evaluate its application in the stabilization of coconut milk emulsions. The enzyme immobilized on chitosan showed the highest yield of lactose ester production (84.1%). Additionally, the production of fructose ester was found to be higher for the enzyme immobilized on the acrylic resin support (74.3%) as compared with the one immobilized on chitosan (70.1%). The same trend was observed for the sucrose ester, although with lower percentage yields. Sugar esters were then added to samples of fresh coconut milk and characterized according to their surface tension, emulsification index and particle size distribution. Although the microscopic analysis showed similar results for all sugar esters, results indicated lactose ester as the best biosurfactant, with a surface tension of 38.0 N/m and an emulsification index of 54.1%, when used in a ratio of 1:10 (biosurfactant:coconut milk, v/v) for 48 h experiments.     

Oral and intestinal digestion of oligosaccharides as potential sweeteners: A systematic evaluation

The utilisation of oligosaccharides by oral microorganisms and intestinal enzymes are important factors in determining their effectiveness as alternative sweeteners. In this study, classes of naturally occurring sugars were assessed using in vitro models for oral and intestinal digestibility, in order to test the influence of chemical structure on functional properties. Amongst the classes of sucrose isomers, α-glucobioses, β-glucobioses and sucrose-based oligosaccharides, structures were identified that were not utilised by the common oral bacterium Streptococcus mutans, and would therefore contribute to the non-cariogenic potential of a sweetener. Analysis of the rate and products of digestion by a rat glucosidase mixture was used to determine the relative intestinal digestibility. The results showed that oligosaccharides containing a (1 → 6)-β-Glc group, including gentiobiose and gentiobiitol, together with melezitose, a sucrose-derived oligosaccharide containing a α-Glc-(1 → 3)-Fru moiety were resistant to digestion by both S. mutans and mammalian intestinal enzymes, highlighting their potential as dietary sugar substitutes.     

Chemical compositions and some physical properties of the water and alkali-extracted mucilage from the young fronds of Asplenium australasicum (J. Sm.) Hook

Effect of extraction conditions, including solvent types (water and sodium bicarbonate) and extraction temperatures (25, 50, 70 and 90 °C), on the physicochemical properties of the water and alkali-extracted mucilage from the young fronds of Asplenium australasicum (J. Sm.) Hook was evaluated. It was found that sodium bicarbonate extract generally showed higher yield than water extract, and its yield increased with increasing extraction temperature. Composition analysis revealed that A. australasicum mucilage was composed of mainly carbohydrates in conjunction with some glycoproteins. The weight average molecular size of the carbohydrate fraction of crude mucilage obtained from alkali and water extractions were about 6.30 × 10⁷ and 2.63 × 10⁷, respectively. Sugar composition analysis revealed that A. australasicum young fronds mucilage contained significant amount of uronic acid (14.3-56.6% based on total sugars). For the water extracted mucilage, GlcA is predominant. However, for the sodium bicarbonate extracted mucilage, GalA is predominant. Furthermore, Rha can only be detected in sodium bicarbonate extract. Other major neutral sugars include Gal, Man, Xyl and Fuc. The intrinsic viscosity of the water and alkali-extracted mucilage in deionized water were around 21.12 and 5.92 dL/g, respectively. This information would be useful when considering A. australasicum young fronds mucilage as a new Agro-ingredient.     

A consistency mapping for the effects on enzymatic hydrolysis sugar yield using two sugar yield definitions in cellulosic biofuel manufacturing

Two different sugar yield definitions (cellulose-based and biomass-based) were used in reported studies investigating the relationship between biomass particle size and enzymatic hydrolysis sugar yield. It is noticed that these reported relationships are not consistent if sugar yield is defined differently. The literature does not contain any reports on the effects of sugar yield definition on the relationship between biomass particle size and enzymatic hydrolysis sugar yield. This paper presents a consistency mapping to show under what conditions the relationships are consistent (or inconsistent) when these two definitions are used. The application of this mapping is illustrated via an experimental study with poplar wood biomass on the relationship between biomass particle size and enzymatic hydrolysis sugar yield using both sugar yield definitions. The application of this mapping is also illustrated via data reported in the literature. Not limited to particle size, this mapping is applicable to investigations of the relationships between a variety of parameters (biomass type, pretreatment condition, etc.) and enzymatic hydrolysis sugar yield.     

融·简中的藤文化——赏析新东方“青藤”系列家具

本文通过对"融·简"的认识,以此上升对于以藤作为一种家具表现材料的思考,又以具体案例—"春在中国"进行实例解说,最后回归于"融·简"文化。     

Assessment of selected properties of LDPE composites reinforced with sugar beet pulp

This study measured the effect of sugar beet pulp (SBP) and maleated polyethylene (MAPE) concentrations on the properties of low density polyethylene (LDPE) composites. SBP concentration has significantly increased density, thickness swelling (TSW), water absorption (WA), flexural strength (FS), tensile modulus (TM) and flexural modulus (FM) of composites while reducing tensile strength (TS), elongation at break (EatB) and impact strength (IS). Presence of MAPE has improved TSW, WA, TS, FS, TM and FM. However, EatB and IS were slightly worsened by MAPE use. Composites showed two main decomposition peaks; one coming from SBP (360–368 °C) and the second one from LDPE degradation (484–490 °C). SEM images showed improved dispersion of SBP. The composites has provided less than 2% weight loss and classified as ‘very durable material’ against white-rot and brown-rot fungi attack. Through this study, potential utilization of SBP in LDPE matrix was demonstrated.     

Beet tissue ensiling: An alternative for long-term storage of sugars in industrial beets for nonfood use

Industrial beets have significant potential to compete against corn grain as an important source of sugars for nonfood industrial processes including microbial bioconversions. However, dependable, long-term storage techniques are necessary to extend processing campaigns and meet increasingly-important industry requirements such as carbon footprint reductions. This work evaluated the potential of industrial-beet tissue ensiling as an alternative for long-term sugar storage. Ground industrial-beet tissue was ensiled for 8 wk at 23 °C and various combinations of pH, moisture content (MC), and sugar:solids (SSR). The pH, MC, and SSR values ranged from 2.0 to 6.8, 50%–85%, and 38%–76%, respectively, according to a central composite rotatable design. Response surface methodology was used to model and illustrate effects of parameter combinations on beet sugar retention. MC and pH had statistically significant effects on sugar retention in beet tissue silage, whereas SSR had no significant effect. Only some combinations of pH ≤ 4.0 and MC ≤ 67.5% enabled the highest sugar retentions in ensiled tissue (≥ 90%). Moreover, tissue ensiled at pH ≤ 3.0 and MC ≤ 67.5% showed increases of ≤ 7% over initial sugars after 3 d of ensiling, suggesting that highly acidic conditions may partially hydrolyze beet tissue cellulose and/or hemicellulose during storage. In contrast, tissue ensiled at some combinations of pH < 6.5 and MC > 67.5% only achieved sugar retentions of < 30% at 8 wk. Sulfuric acid cost estimates (on a dry-sugar basis) to achieve effective pH (2.0–4.0) for sugar retentions ≥ 90% range from $4.9 Mg⁻¹ to $18.6 Mg⁻¹.     

Hot-Water Extraction Optimization of Sugar Maple (Acer saccharum Marsh.) and Red Maple (Acer rubrum L.) Bark Applying Principal Component Analysis

In the forest industry, bark is an abundant residue, predominantly converted into calorific energy. As the antioxidant potential of phenolic compounds from sugar maple (Acer saccharum Marsh.) and red maple (Acer rubrum L.) bark has previously been established, the present study focused on the hot-water extraction optimization of these barks. Several process parameters (maple species, temperature, duration, ratio bark/water, particle size) were thus studied and large disparities were found between the two species. Extraction yield, phenolic content, and antioxidant capacity of red maple extracts were several times higher than those of sugar maple extracts. Principal component analysis, applied to the selected best extraction conditions, identified 3–4 clusters depending on the maple species. These groups were sorted from the highest extraction yield and energy consumption combined with the lowest phenolic content and antioxidant capacity, to moderate extraction yield and energy consumption with the highest phenolic content and antioxidant capacity.     

Modelling and prediction of bioethanol production from intermediates and byproduct of sugar beet processing using neural networks

The aim of this work was to model and predict the process of bioethanol production from intermediates and byproduct of sugar beet processing by applying artificial neural networks. Prediction of one substrate fermentation by neural networks had the same input variables (fermentation time and starting sugar content) and one output value (ethanol content, yeast cell number or sugar content). Results showed that a good prediction model could be obtained by networks with single hidden layer. The neural network configuration that gave the best prediction for raw or thin juice fermentation was one with 8 neurons in hidden layer for all observed outputs. On the other side, the optimal number of neurons in hidden layer was found to be 9 and 10 for thick juice and molasses, respectively. Further, all substrates data were merged, which led to introducing an additional input (substrate type) and defining all outputs optimal network architecture to 3-12-1. From the results the conclusion was that artificial neural networks are a good prediction tool for the selected network outputs. Also, these predictive capabilities allowed the application of the Garson's equation for estimating the contribution of selected process parameters on the defined outputs with satisfactory accuracy.