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Advantame is a novel sweetener, and 3‐hydroxy‐4‐methoxy benzal acrolein is an important intermediate to synthesize the sweetener. The aim of this study was to evaluate a new low‐cost method to purify 3‐hydroxy‐4‐methoxy benzal acrolein, and the crude intermediate was used as raw material. The intermediate was purified using a low‐pressure column chromatography with a C18 column, using a methanol‐water (6:4, v/v) at a flow rate of 6.0 ml/min, and the loading amount of the crude intermediate in solution was 10.0 mg in total. A method for the analysis of 3‐hydroxy‐4‐methoxy benzal acrolein was established using high‐performance liquid chromatography (HPLC). This method was validated in terms of its linearity, repeatability, accuracy, detection limit, and quantitation limit. The calibration curves of 3‐hydroxy‐4‐methoxy benzal acrolein were linear (r > .999) over a wide concentration range of 0.005–0.08 mg/ml, by comparing the ratio of signal to noise, and the detection limit was 5.0 ng/ml and the quantification limit was 15.0 ng/ml. Good repeatability was obtained (RSD, In this study, a new low‐cost method for the preparation and purification of a sweetner intermediate named 3‐hydroxy‐4‐methoxy benzal acrolein was described. The purifying method and analysis method could be a reference to develop other sweetener intermediates.

Two novel polysaccharide fractions (HLP1-1 and HLP2-1) were purified from crude polysaccharides of Helvella leucopus by using DEAE-52 column (2.6cm×20cm) and Sephadex G-150 column (1.6×60cm). The characterization, antioxidant and anticancer activities of HLP1-1 and HLP2-1 were investigated. The GPC results showed that HLP1-1 and HLP2-1 had similar molecular weight (21,382Da and 23,063Da, respectively). Tertiary structure analyses indicated that HLP2-1 had triple-helical conformation, but HLP1-1 not. The monosaccharide compositions of HLP1-1 included rhamnose, glucosamine and mannose at a molar ratio of 11.8:1:78.6, and HLP2-1 included of rhamnose, glucosamine, glucose and mannose at a molar ratio of 4.2:1:18.1:27.3. Both HLP1-1 and HLP2-1 showed a certain antioxidant activity, and HLP2-1 showed stronger antioxidant activities than HLP1-1. Both HLP1-1 and HLP2-1 exhibited a relatively inhibition on HepG2.

A stepwise ethanol-precipitation (SEP) procedure was developed for the purification of sugar beet pectins (SBP) from a pectin-containing aqueous extract. Five fractions of different chemical and molecular characteristics were produced by stepwise elevating the alcohol concentration of the precipitation medium from 50% to 80% v/v. Comparison of chemical and macromolecular features between the obtained fractions indirectly suggested that the ability of pectin to solubilize in the ethanol-water binary mixture depended greatly on the polymer structure. Fractions rich in neutral sugars were precipitated at relatively high ethanol concentrations, probably due to the enhanced interactions generated between pectin side chains and solvent molecules. Furthermore, the obtained fractions displayed different surface activities. Results obtained in this work indicate that the SEP procedure is more selective with respect to pectin structural features and surface properties than the one-step ethanolic precipitation.

Sugar beet pectins (SBP) were precipitated from a purified extract in a 75% v/v ethanol solution at an initial extract pH (I-pH) ranging from 2.0 to 4.5. The effects of I-pH on pectin yield and pectin-cation interactions were studied. No simple correlation between pectin yield and I-pH was observed. The lowest pectin yield was obtained by precipitating the acidic pectin extract with ethanol at I-pH 4.5. Pectin yield increased to a maximum value as I-pH decreased from 4.5 to 3.0. These results indicated that decreased electrostatic repulsion between pectin chain segments enhanced pectin chain–chain interactions, thereby improving the precipitation effect. A decrease in pectin yield was observed as I-pH decreased below 3.0. The cation content of various samples was measured by high-performance cation-exchange chromatography in order to determine the content of SBP-bound cations during precipitation. Cation content and degree of cation binding were measured for pectins precipitated at I-pH 3.0, 2.5, and 2.0, and the results revealed that a decrease in pectin yield accompanied a decrease in cation–pectin interactions. These results suggest that the precipitation of SBP from an aqueous extract involves complex interactions between cations, solvent molecules, and pectin chain segments. The larger precipitation effect observed with divalent ions compared to monovalent ions may be due to enhanced inter-chain interactions between pectin molecules, probably via the formation of intermolecular bonds.

Short chain amylose (SCA) was obtained by debranched waxy rice starch. The SCA crystals was formed by crystallization and dried by freeze drying, air drying and spray drying. The physicochemical properties and digestibility of the dried crystals were investigated. Light microscope and scanning electron microscopy revealed that the air dried crystals exhibited compact structure, but freeze dried crystals showed loose and porous morphology. Spray dried crystals showed sphere morphology. Air dried crystals had a higher relative crystallinity and a higher melting temperature as compared with the crystals dried by freeze and spray drying. The digestibility analysis showed that air drying was the preferred method for the formation of resistant starch in SCA crystals, while spray drying favor to obtain products with high level of slowly digestible starch. The tight pack of double helix could be responsible for the enzyme resistance of air dried crystals.

Metal precipitation is an effective method for the purification of pectins. To study the selectivity of copper ions toward binding pectic or non-pectic compounds, two fractions, namely copper-precipitated pectins (CPP) and copper-unprecipitated pectins (CUP) were fractionated from the mother sugar beet pectins by means of copper precipitation. Comparison on chemical feature revealed the isolated fractions were structurally different in that CUP contained markedly higher neutral sugars (NS) and protein contents, but lower galacturonic acid and acetyl ester group contents than CPP. However, no appreciable difference was observed in terms of degree of methylation (DM). Elution profiles on high performance size exclusion chromatograph showed that CPP exhibited a monomodal-like molecular weight distribution (MWD), while CUP demonstrated a multimodal-like MWD pattern composed of three relatively broad peaks, and a narrow peak that was associated with a high intensity of UV signal at 278 nm. Moreover, AFM analysis showed that CPP displayed branched fibrous structures, while CUP showed distinguishable granular-like shapes. Results obtained in this work indicate the employed copper ions selectively bind the anionic regions among pectin chains, thereby separating pectic saccharides from non-uronide compounds, i.e. low molecular weight carbohydrates and free proteins. The poor affinity of copper ions toward CUP might be determined by the absence of typical homogalacturonan (HG) regions.

Effects of precipitation modes on the co-precipitation of insoluble oxalates particles during the purification of sugar beet pectins (SBP) from the extract were investigated. It was observed that soluble oxalate ions formed insoluble oxalate salts with calcium and precipitated with pectins during ethanol precipitation as pH of the medium increased and the solvent changed from water to ethanol-water mixture. Comparison among the employed precipitation methods revealed that both the dialysis-ethanol-precipitation and metal precipitation effectively prevented the calcium-oxalate contamination of SBP. Emulsifying properties of DEPP, EPP and MPP were also studied. It was observed that DEPP performed better than the remainder with respect to emulsifying ability. Based on these results, we concluded that the dialysis-ethanolic-precipitation can be a suitable method for improving the purity as well as emulsifying properties of the resulting pectins.

Slowly digestible starch (SDS) was obtained through debranched waxy rice starch and subsequent crystallization under isothermal and temperature-cycled conditions. Temperature-cycled crystallization of dual 4/−20 °C produced a higher yield of SDS product than isotherm crystallization. Crystal structure of SDS products changed from A-type to a mixture of B and V-type X-ray diffraction patterns. The relative crystallinity was higher in the temperature-cycled samples than that of isotherm. Attenuated total reflectance Fourier transform infrared spectroscopy suggested that the peripheral regions of isothermal storage starch were better organized than temperature-cycles. Temperature cycling induced higher onset temperature for melting of crystals than isothermal storage under a differential scanning calorimeter. The cycled temperature storage induced a greater amount of SDS than the isothermal storage.

This work reports on a modification of the standard Quentin method by the use of Ca2+- enriched brine obtained by electrodialysis (ED) treatment of thin juice to regenerate the Ca2+ form of the resin used to remove of K+ and Na+ in mother liquor B. Results showed that after the ED treatment was carried out under the best operating conditions (voltage of 1.17 V/Cell and recirculating flow rate of 70 l/h), BK001 resin was regenerated within 3.6 h with a Ca2+ exchange capacity of 53.9 mg CaO per ml wet resin. The ED treatment removed 61.3% of conductive ashes in the thin juice, and its purity was increased from 90.0% to 92.3% while continuously treating thin juice under the optimal conditions. The modified method has potential to improve the sugar yield in beet sugar industry.

Summary Effects of ultrasound on pH, intermediate products, browning, maltose content, reducing power and antioxidant activity of a glycin–maltose solution were investigated. Results showed that the ultrasonic treatment at the intensity of 17.83 W cm−2 for 100 min resulted in the increases of the solution’s absorbance at 294 and 420 nm and the antioxidant activity from approximately 0% to 1.06%, 0.30% and 22.53%, respectively. At the same time, 86.93% reduction in maltose was observed. In addition, little 5-hydroxymethyl-2-furaldehyde was found in HPLC analyses. This study indicated that ultrasound, especially at higher intensities, could potentially be employed as a means to promote the Maillard reaction in the glycin–maltose solution.

This paper was aimed at characterising the insoluble substances (IS) responsible for the turbidity of the extract and impurity of the resulting pectins. Results showed that the IS caused a significant increase in the turbidity of the extract. The IS had bi-pyramidal shapes under the SEM observation. The observed XRD peaks for the IS were similar to those of calcium oxalate dihydrate (COD). Moreover, the IS consisted of mainly oxalate and calcium. Results from the present study indicate the IS is COD. The influence of the IS on the purity of pectin was also studied. The presence of the IS in the pectins indicated the IS can precipitate with pectins during the alcohol precipitation, thereby contaminating the resulting pectins.