Production of high purity fructose from barley syrups using semi-continuous chromatography

A semi-continuous counter current chromatographic refiner, developed in this department, was used to produce high fructose syrup from an industrial barley syrup containing 42% fructose, 52% glucose and 6% maltose and oligosaccharides. The chromatographic refiner consisted of twelve 5.4 cm i.d. columns, each packed to a height of 65.5 cm with KORELA VO7C calcium charged resin, with a particle size range 150–300 μm. At a throughput of 32.1 kg sugar solids/m³ resin/h, the fructose rich product obtained was 95% pure and had a concentration of 11.3% w/v, while the glucose rich product contained only 4.5% fructose and had a concentration of 22.56% w/v.     

Adult Parasitoids of Honeydew-Producing Insects Prefer Honeydew Sugars to Cover their Energetic Needs

To meet their carbohydrate requirements, adult parasitoids exploit a broad range of sugar resources, including floral and extrafloral nectar and honeydew. Although honeydew might be the predominant sugar source, especially in agricultural systems, it often is nutritionally inferior to sugar sources like nectar. Given its broad availability, it may be expected that sugar-feeding insects have evolved specialized adaptations to deal with this typically inferior sugar source. This would apply especially to organisms that have a close association with honeydew producers. Here, we hypothesized that parasitoids of honeydew-producing insects should show a pronounced response to sugars, such as fructose, sucrose, melezitose, and trehalose, and to a lesser extent glucose. To test this hypothesis, we investigated sugar consumption, feeding behavior and survival of the aphid parasitoid Aphidius ervi on several sugars (equiweight solutions). Our results show that A. ervi adults consumed typical honeydew sugars (sucrose, fructose, trehalose, and melezitose) the most, while consuming considerably less glucose or melibiose. Rhamnose, which does not occur in aphid honeydew, was not, or was only marginally, consumed. When different sugars were provided at the same time, A. ervi adults preferred sucrose or fructose over glucose or melezitose. Furthermore, pre-exposure to sucrose or fructose significantly reduced subsequent intake of glucose, suggesting an acquired distaste for glucose after being previously exposed to highly preferred sugars such as sucrose and fructose. Altogether, this study shows that A. ervi adults prefer sugars (fructose, melezitose, trehalose, and sucrose) that are overrepresented in aphid honeydew and show a lower preference to one (glucose) that is underrepresented in honeydew.     

Utilization of raffinose and melibiose by a mutant of Saccharomyces cerevisiae

The mutant Saccharomyces cerevisiae ATCC 36858 was used in the production of ethanol and/or fructose from synthetic media in batch processes with raffinose, melibiose or sucrose. The mutant was able to hydrolyze all the sugars used and to selectively ferment glucose and galactose to ethanol while fructose accumulated in the fermentation medium. The fructose yield was above 89% of the theoretical value in the media with either raffinose or sucrose, when initial concentrations were between 131.5 g dm^?3 and 242.0 g dm^?3. The ethanol yields were 82% and 77% of the theoretical values in the media with melibiose and sucrose, respectively, and about 72% of the theoretical value when raffinose was used. The fructose fraction in the carbohydrate content of the produced syrups was more than 96% when raffinose concentration was below 189.1 g dm^?3. However, even at a sucrose concentration of 187.9 g dm^?3, the produced syrup contained 100% fructose. Some oligosaccharides were also produced in all tested media. The produced oligosaccharides were consumed by the end of the fermentation process. These findings can be useful in the production of ethanol and high fructose syrups using raw materials based on sucrose and raffinose such as molasses. Copyright © 2003 Society of Chemical Industry     

Pure fructose syrup and ethanol production from high fructose corn syrup supplemented with Jerusalem artichoke juice

Saccharomyces cerevisiae ATCC 36859 preferentially consumes glucose from glucose–fructose mixtures. Synthetic media and complex media containing high fructose corn syrup supplemented with Jerusalem artichoke juice were used for the production of pure fructose syrup by the conversion of glucose to ethanol. Fructose was not converted in these processes. Increasing the concentration of Jerusalem artichoke juice increased the yields of ethanol and biomass and decreased the process time. A similar effect was obtained at a low juice concentration when a larger amount of biomass was used for the inoculum. The product from this process contained only fructose and ethanol. Use of food-grade materials results in a pure fructose syrup that is suitable for human consumption.     

Effects of three main sugars in cane molasses on the production of butyric acid with <Emphasis Type="Italic">Clostridium tyrobutyricum</Emphasis>

The effects of three main sugars in cane molasses were investigated systematically to prepare a cost-effective medium for butyric acid bioproduction. Additionally, 30 g/L corn steep liquor was screened out as the suitable nitrogen source. In the batch fermentation of free cells, when 60 g/L glucose was the only carbon source, 21.28 g/L butyric acid was achieved after 30 h cultivation. Similar product concentration, productivity and yield were obtained when 60 g/L fructose was applied. The utilization of sucrose would bring about lower productivity (0.29 g/L·h) and product concentration (18.15 g/L), but the yield of butyric acid/sucrose (0.34 g/g) is almost the same as that from glucose or fructose (0.35 g/g). Finally, the sugar mixture (15 g/L glucose, 20 g/L fructose and 35 g/L sucrose) was employed to produce butyric acid in a fibrous-bed bioreactor (FBB), and 40.11 g/L butyric acid was produced with one simple fed-batch strategy.     

Production of fructose and ethanol from media with high sucrose concentrations by a mutant of Saccharomyces cerevisiae

The production of enriched fructose syrups and ethanol from a synthetic medium with high sucrose concentrations was studied in a batch process using Saccharomyces cerevisiae ATCC 36858. The results showed that the fructose yield was above 92% of theoretical values in synthetic media with sucrose concentrations between 180 g dm^?3 and 726 g dm^?3. Ethanol yield was about 82% in media with sucrose concentrations up to 451 g dm^?3. A product containing 178 g dm^?3 fructose, which represents 97% of the total sugar content, and 79 g dm^?3 ethanol was obtained using a medium with 360 g dm^?3 sucrose. The fructose fraction in the carbohydrates content in the produced syrups decreased with increases in the initial sucrose concentration. In a medium with initial sucrose concentration of 574 g dm^?3, the fructose content in the produced broth was 59% of the total carbohydrates. Glycerol and fructo‐oligosaccharides were also produced in this process. The produced fructo‐oligosaccharides started to be consumed when the concentration of sucrose in the media was less than 30% of its initial value. Complete hydrolysis of these sugars was noticed in media with sucrose concentrations below 451 g dm^?3. These findings will be useful in the production of ethanol and high fructose syrups using sucrose‐based raw materials with high concentrations of this carbohydrate. © 2001 Society of Chemical Industry     

UPLC-ELSD法测定烟草中的水溶性糖

采用Waters公司的ACQUITY UPLC BEH Amide色谱柱,建立烟草中水溶性糖的超高效液相-蒸发光散射(UPLC-ELSD)检测方法。果糖、葡萄糖、蔗糖和麦芽糖4种水溶性糖在6.5 min之内分离完全,线性相关系数(R2)果糖:0.999 5,葡萄糖:0.999 8,蔗糖:0.999 9,麦芽糖:0.997 4,回收率依次分别为106.5%,102.4%,91.2%,100.1%,表明方法可用于烟草中水溶性糖的稳定、快速、准确分析。     

HPLC-RI测试果葡糖浆中的果糖和葡萄糖

建立并验证了用高效液相色谱-示差折光检测器测定果葡糖浆中果糖和葡萄糖含量的检测方法。以水为溶剂,Ca型阳离子交换柱进行分离;以相对保留时间定性,色谱峰面积定量。方法平均回收率为98.33%~102.69%,RSD为0.865%~1.253%,检测限(S/N=3)分别为葡萄糖1.94μg/mL;果糖2.49μg/mL。实验表明该方法对果葡糖浆中的葡萄糖和果糖含量的测试简单、可靠。     

The effects of four hypocaloric diets containing different levels of sucrose or high fructose corn syrup on weight loss and related parameters

ABSTRACT: BACKGROUND: The replacement of sucrose with HFCS in food products has been suggested as playing a role in the development of obesity as a public health issue. The objective of this study was to examine the effects of four equally hypocaloric diets containing different levels of sucrose or high fructose corn syrup (HFCS). METHODS: This was a randomized, prospective, double blind trial, with overweight/obese participants measured for body composition and blood chemistry before and after the completion of 12 weeks following a hypocaloric diet. The average caloric deficit achieved on the hypocaloric diets was 309 kcal. RESULTS: Reductions were observed in all measures of adiposity including body mass, BMI, % body fat, waist circumference and fat mass for all four hypocaloric groups, as well as reductions in exercise only group for body mass, BMI and waist circumference. CONCLUSIONS: Similar decreases in weight and indices of adiposity are observed when overweight or obese individuals are fed hypocaloric diets containing levels of sucrose or high fructose corn syrup typically consumed by adults in the United States.     

Effect of Alcohol in Starch-Thickened Fillings on the Storage Stability of Dark Chocolate Pralines

Commercial praline shells made from dark chocolate were filled with a mixture of invert sugar syrup, wine distillate and sucrose, which was adjusted to a viscosity of approximately 4 Pa·s by addition of pregelatinized starch. The pralines which also contained malt extract were subjected to storage at 20 and 24 °C. The liquefaction rate induced by enzymes of the malt extract depended on ethanol (0–15% w/w) and moisture content (approximately 30%) of the filling, and on storage temperature. The decay of apparent viscosity immediately after adding malt extract was delayed when ethanol was present in the filling, implying that viscosity stability after mixing and during subsequent processing is improved. Softening of the praline shells and fat bloom formation also depended on the ethanol concentration of the filling. A cross-comparison with praline shells which were filled with pure invert sugar syrup implies that the enzymes of the malt extract do not exhibit a negative influence on praline shell firmness. Electron micrographs give evidence that ethanol in contact with chocolate causes structural damage which results in a partial solubilization of praline shells.     

Thermodynamic measurement and modeling of hydrate dissociation for CO2/refrigerant + sucrose/fructose/glucose solutions

Hydrate dissociation conditions were studied for the CO₂/refrigerant + sucrose/fructose/glucose solution systems as a continuation of previous work into alternate separation technologies for the sugar manufacturing industries. Experimental data were measured following the isochoric pressure method for the CO₂ + sucrose/fructose solution systems. The refrigerants studied for the modeling purpose were R410a, R507, R134a, and R22 using literature data. The pressure and temperature ranges for the experimental data measured here were (1.80–4.10) MPa and (276.6–282.6) K, respectively, with solutions measured in the composition range between 0 to 0.40 mass fraction sucrose and fructose. Several models following the Van der Waals–Platteeuw solid solution theory were developed to predict the hydrate dissociation conditions of CO₂/fluorinated refrigerant in the presence of sucrose/fructose/glucose solutions. The modeling results provide a satisfactory representation of the experimental data, with AARD(P) % model errors in the overall range between 0.03% and 4.40%.     

Wood blocks as a carrier for Saccharomyces Cerevisiae used in the production of ethanol and fructose

Saccharomyces cerevisiae ATCC 39859 was immobilized onto small cubes of wood in order to produce very enriched fructose syrup from synthetic glucose-fructose mixtures, through the selective fermentation of glucose. The kinetics of growth and ethanol production rates were studied. Several tests to assess the influence of substrate and product concentration on the production rates were carried out and appropriate rate equations were proposed as a design basis for continuous immobilized reactors. The ethanol production rate and cell growth rate were found to be inhibited linearly by both substrate and product concentrations. A maximum ethanol productivity of 21.9 g 1⁻¹ h⁻¹ was attained from a feed containing 10% (by weight) glucose and 10% (by weight) fructose. The ethanol concentration was 29.6 g 1⁻¹, the glucose conversion was 78% and a fructose yield of 99% was obtained. This resulted in a final fructose:glucose ratio of 2.7. At lower ethanol productivity levels the fructose:glucose ratio increased, as did the ethanol concentration in the effluent. The ethanol productivities obtained in this study were 33%–132% higher than those obtained in a previous study using the same system, under similar conditions, with the cells immobilized in alginate beads.     

The recovery of fructose from inverted sugar beet molasses using continuous chromatography

The continuous chromatographic separation of inverted beet molasses resulting in a fructose rich product and a product containing glucose and other non-sugars was carried out using a semi-continuous countercurrent chromatographic refiner (SCCR6), consisting of ten 10.8 cm diameter by 75 cm long stainless steel columns packed with a calcium charged 8% cross-linked polystyrene resin, zerolit SRC14. It was found that cations present in beet molasses displaced calcium ions from the resin resulting in poor separation of the glucose and fructose. Three methods of maintaining the calcium form of the resin during the continuous operation of the equipment were established. Passing a solution of calcium nitrate through the purge column for half a switch period was found to be most effective as there was no contamination of the main fructose rich product and the product concentrations were increased by 50%.     

Sugaring‐Out Separation of Acetonitrile from Its Aqueous Solution

The separation of acetonitrile (ACN) from an ACN‐water azeotrope is of particular interest to industrial chemists and process engineers. In the work reported in this article, sugaring‐out, a new phase separation method is reported and used to obtain high purity ACN from an ACN‐water mixture. With the addition of a mono‐sugar (glucose, xylose, arabinose or fructose) or a disaccharide (sucrose or maltose) into an ACN‐water mixture, a phase separation is observed if the sugar concentration exceeds a threshold. The upper phase is rich in ACN while the lower phase is rich in water. The ACN concentration in the upper phase increases when more sugar is added into the ACN‐water mixture. When the glucose concentration is > 35 g/L, the ACN concentration in the upper phase is > 40 %. In the Sudan I extraction test with a glucose‐triggered two‐phase system, an extraction rate of > 80 % is achieved when the glucose concentration is greater than 25 g/L.     

果糖生产技术概述

概述了果糖的技术发展和生产技术,介绍了采用菊粉水解、蔗糖水解及淀粉水解异构化等方法制备果葡糖浆技术,以及用模拟移动床(SMB)技术和复盐法、果糖结晶法分离果葡糖的工艺。综合国内外市场现状指出中国果糖市场的发展前景广阔。     

Reuse of Sucrose Syrup in the Osmotic Dehydration of Peaches

The objective of this work was to determine the technical feasibility of reusing sucrose syrup during the osmotic dehydration of peaches combined with hot air drying (OD/HD). Two trials using different reconditioning methods were carried out over 15 OD/HD cycles, using new syrup in the first cycle and reconditioned syrup in the following ones. The first method consisted of sieving, vacuum concentration, and syrup replacement. The second included filtration through diatomaceous earth. After OD (65°Brix/50°C/4 h), the fruits were dried using a forced air dryer (65°C). The OD parameters of water loss and solids incorporation were evaluated, and physical, chemical, and microbiological analyzes were carried-out on the raw material, syrup, and products. Sensory tests were carried-out using the difference from control method. For both methods, the syrup showed increases in titratable acidity, electrical conductivity, and reducing sugar content over the cycles, but the pH decreased. The syrup turbidity increased without filtration, but for both methods the reconditioning process had no effect on the OD parameters or microbiological load. Both reuse methods favored maintenance of the yellow color of the dried peach and did not influence the flavor and sensory texture.     

非水相中酶法合成糖酯的研究进展

回顾了非水相酶法合成糖酯的研究进展,重点介绍了葡萄糖酯、果糖酯、蔗糖酯、麦芽糖酯和木糖醇酯的合成方法,分析了酶、溶剂、脂肪酸等对糖酯收率的影响,比较了不同糖酯酶法合成的相似性及差异性。并对其研究方向和发展前景进行了展望:酶法合成糖酯具有反应条件温和、选择性高、低毒环保等优点;采用新型反应介质、寻求既经济又环保的分离纯化方法和降低成本是研究的重点。     

Production of low calorie Malay apples by dual stage sugar substitution with Stevia-based sweetener

The present study describes a new process denominated dual stage sugar substitution (D3S). This process aims to substitute high calorie sugars of Malay apples for a low calorie natural sweetener. In a first stage, high calorie sugars (sucrose, fructose and glucose) are partially removed from the fruit samples and in a second stage, low calorie sugars (stevioside and rebaudioside) are incorporated to the fruit to maintain its sweetness. The use of ultrasound was evaluated on both stages of the D3S process. Best performance of the process was obtained by subjecting the fruit samples to ultrasound in the sugar removal stage followed by immersion of the samples in Stevia-based solution with application of ultrasound in the sweetener incorporation stage. These operating conditions resulted in the highest sugar removal during the first stage, highest water loss during the process and highest sweetener incorporation during the second stage of the D3S process.     

PROPERTIES OF A SUCROSE SOLUTION REUSED IN OSMOTIC DEHYDRATION OF APPLES

The reuse of concentrated solutions for osmotic dehydration (OD) must be clearly understood to guarantee the economic viability of this process. This study was carried out to determine the modifications that a sugar solution undergoes when used 20 times during the OD of apple cubes by measuring the evolution of its different physico-chemical properties. Before beginning a new OD process, the syrup's mass was readjusted lo its initial value by the addition of crystallized sucrose. An increase of 3.4% in the mass of the syrup was observed after each OD process. The pH of the syrup stabilized after the third reuse, while its acidity, reducing sugars, and electrical conductivity stabilized after six reuses to values similar to those of the osmodehydrated apples. Under the specific conditions of this experiment, neither acid hydrolysis nor enzymatic hydrolysis in the sugar solution was observed. Microbiological analysis of syrup showed high levels of yeast and molds only after the 15th use. Progressive increases in turbidity, browning, and insoluble solids in the syrup were observed during the course of its utilization.     

Effect of Sugar Pretreatment on Quality of Dehydrated Cabbage

To reduce the cost of osmotic treatment with glucose and fructose in production of dehydrated cabbage, use of a low-price additive, namely, high-maltose syrup, as an osmotic agent was investigated. The results showed that high-maltose syrup had more efficient dehydration and osmosis capability than fructose. Effect of additives on drying rate at 80 and 65°C was also investigated. Osmotic pretreatment with high-maltose syrup was helpful in reducing energy consumption and for enhancement of the drying rate.