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Electron beam irradiation was proven to be a successful method in aflatoxin degradation in earlier researches. However, the exact nature of the result radiation products generated by the aflatoxins remains unknown. Based on ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF MS) analysis, the solution of aflatoxin B1 (AFB1) in acetonitrile irradiated by electron beam degraded to two kinds of major products. The doses employed were in the range of 0 (control) to 8.60 kGy. The absorbed doses were monitored with FWT-60-00 radio-chromic dosimeters. By using UPLC-Q-TOF MS, accurate masses and proposed molecular formula for the degradation products, 261.1233 m/z (C14H13O5) and 299.1104 m/z (C17H15O5), were obtained from low mass error and high matching properties. Structural formula for the radio-degradation products and the degradation pathways leading to the compounds were proposed, based on the molecular formula and MS-MS spectra. The results showed that electron beam (EB) irradiation is an effective method for degrading AFB1.

Meat and bone meal (MBM), a type of protein feed source, with high nutritional value, has been widely used as feed in China. In order to study the effect of defatting on the quality of MBM, MBM were defatted by hexane, and their basic nutritional components, color, flavor, protein characteristics, freshness indexes before and after defatting, were investigated. The crude protein content of the defatted MBM was increased from 54.5% to 61.2%, lysine content increased from 1.83 to 1.96%, pure protein content and in vitro digestibility of MBM were increased to 50.7% and 90.45%, respectively. Acid value decreased from 9.0 to 2.6 mg potassium hydroxide/g, and the color and flavor were also improved after defatting. Furthermore, volatile basic nitrogen content decreased from 60 to 40 mg/100 g and histamine content did not change significantly (decreasing from 20.1 to 19.6 mg/kg). Therefore, defatting treatment was good for the quality improvement of MBM.

Production of human milk fat substitutes (HMFSs) from three types of palm stearin with palmitic acid (PA) of 91.3, 70.3 and 62.6 %, respectively, was scaled up to a kilogram scale. The physiochemical properties of these products including fatty acid profiles, triacylglycerol compositions, tocopherol contents, oxidative stability and melting and crystallization profiles were compared with those of HMFSs from lard, butterfat and tripalmitin and fats from infant formulas. Based on their chemical compositions, HMFSs from palm stearin with PA contents of 70.3 and 62.6 % produced by enzymatic acidolysis were found to have the highest degree of similarity to human milk fat, which indicated that these HMFSs were the most suitable for use in infant formulas. However, HMFSs from palm stearin with PA content of 91.3 % had the highest tocopherol contents. By investigation of the primary and secondary oxidation products during accelerated oxidation, the oxidative stability of HMFSs was found to be positively correlated to the contents of tocopherols, and the volatile oxidation compounds with the highest relative contents in HMFSs were aldehydes analyzed by solid-phase microextraction-GC–MS. All HMFSs had final melting points lower than body temperature.

Human milk fat substitutes (HMFSs) with triacylglycerol profiles highly similar to those of human milk fat (HMF) were prepared from lard by physical blending followed by enzymatic interesterification. Based on the fatty acid profiles of HMF, different vegetable and single-cell oils were selected and added to the lard. Blend ratios were calculated based on established physical blending models. The blended oils were then enzymatically interesterified using a 1,3-regiospecific lipase, Lipozyme RM IM (RML from Rhizomucor miehei immobilized on Duolite ES562; Novozymes A/S, Bagsvaerd, Denmark), to approximate HMF triacylglycerol (TAG) profiles, particularly with respect to the distribution of palmitic acid in the sn−2 position. The optimized blending ratios were determined to be: lard:sunflower oil:canola oil:palm kernel oil:palm oil:algal oil:microbial oil = 1.00:0.10:0.50:0.13:0.12:0.02:0.02. The optimized reaction conditions were determined to be: enzyme load of 11 wt%, temperature of 60 °C, water content of 3.5 wt%, and reaction time of 3 hours. The resulting product was evaluated for total and sn−2 fatty acids, polyunsaturated fatty acids, and TAG composition. A high degree of similarity was obtained, indicating the great potential of the product as a fat alternative for use in infant formulas.

Being the dominant components in human milk fat (HMF), triacylglycerol (TAG) composition might be the best approximation index to represent the composing characteristics of HMF. In this study, TAG composition of HMF from different lactation stages was analyzed by RP-HPLC-APCI-MS, and the establishment of a model for the precise evaluation of human milk fat substitutes (HMFSs) based on TAG composition was indirectly realized by employment of fatty acid composition and distribution and polyunsaturated fatty acid (PUFA) and TAG compositions. The model was verified by the selected fats and oils with specific chemical compositions, and the results revealed the degrees of similarity of these fats and oils in different evaluation aspects reflected their differences in corresponding chemical composition with HMF. The newly established evaluation model with TAG composition as a comparison base could provide a more accurate method to evaluate HMFSs and might have some inspirations for HMFS production in the future.

Human milk fat substitutes (HMFSs) were prepared by a two-step process, namely, Lipozyme RM IM-catalyzed acidolysis of interesterified high-melting palm stearin with fatty acids from rapeseed oil and blending of the enzymatic product with the selected oils on the basis of the calculation model. The optimum conditions for the enzymatic reaction were a mole ratio of palm stearin/fatty acids 1:10, 60 °C, 8% enzyme load (wt % of substrates), 4 h, and 3.5% water content (wt % of enzyme); the enzymatic product contained 39.6% palmitic acid (PA), 83.7% of the fatty acids at sn-2 position were PA (sn-2 PA), and the distribution probability of PA at the sn-2 position among total PA (% sn-2 PA) was 70.5%. With the fatty acid profiles of human milk fat (HMF) as a preferable goal, a physical blending model was established for the second step to guarantee the maximum addition of selected oils. Based on the model prediction, a desirable formula constituted enzymatic product/rapeseed oil/sunflower oil/palm kernel oil/algal oil/microbial oil at a mole ratio of 1:0.28:0.40:0.36:0.015:0.017, and the final product had PA content, sn-2 PA, and %sn-2 PA at 23.5, 43.1, and 61.1%, respectively. The contents of arachidonic and docosahexaenoic acids were 0.4 and 0.3%, respectively. Relying on the total and sn-2 fatty acid compositions of HMF and "deducting score" principle, the score for the similarity between the final product and HMF was scaled as 89.2, indicating the potential as a fat substitute in infant formulas.

The physicochemical properties of human milk fat globules (MFG) at different lactation stages from Danish mothers and the microstructure changes of MFG membrane (MFGM) at varied temperatures were investigated, and the relationship between chemical composition and the microstructure of MFGM was elucidated. The fat content in MFG was found to be significantly increased as lactation progressed, and colostrum MFG had the largest mean diameter of 5.75 ± 0.81 μm and the lowest ζ potential of -5.60 ± 0.12 mV. Chemical composition analyses of MFG revealed the following: (i) Colostrum milk fat constituted higher content in PUFAs (ω-6, and long-chain ω-6 and ω-3) than transitional and mature milk fats, with the corresponding lower content of SFA in its sn-2 position. (ii) The content of polar lipids among total lipids varied during lactation course (maximized at transitional stage); however, in terms of subclasses of polar lipids, no significant change of the relative content of sphingomyelin was observed, while the content of phosphatidycholine in mature milk was higher than that in colostrum and transitional milk. (iii) Inspection of fatty acid composition in phospholipids from different lactation milk revealed no remarkable and regular changes could be generalized; and no obvious difference of the morphologies of MFGM at different lactation stages can be visualized. An investigation of the microstructure change of MFGM vs temperature demonstrated that the segregated domains became larger as temperature decreased to 4 °C, while it became smaller when increased to 37 °C. This phenomenon indicated that, in addition to sphingimyelin and cholesterol, phospholipids might also contribute to increasing the segregated domains at lower temperature, while, at elevated temperature, these domains could be diminished, most likely due to a restructuring or distributing of sphingimyelin and cholesterol.

Six rectangular block all beef tallow (BT)-based and all palm oil (PO)-based model shortenings prepared on a laboratory scale, respectively denoted BTMS and POMS, were stored under temperature fluctuation cycles of 5-20 °C until granular crystals were observed. The lipid composition and thermal, polymorphic, and isothermal crystallization behaviors of the granular crystals and their surrounding materials separated from BTMS and POMS, respectively, were evaluated. The changes of nanostructure including the aggregation of high-melting triacylglycerols (TAGs) and polymorphic transformation from β' form of double chain length structures to complicated crystal structures, in which the β and β' form crystals of triple and double chain length structures simultaneously coexist, had occurred in granular crystals compared with surrounding materials, whether in BTMS or in POMS. Consequently, a slower crystallization rate appeared in granular crystal parts of both model shortenings noted above, which would yield larger and fewer crystals indicated by the Avrami model analysis that would further aggregate to form large granular crystals.

The effects of aflatoxin B1 (AFB1) were studied using the HepG2 cell line. Cytotoxicity, apoptosis and p53 expression were assessed after exposure to different concentrations of AFB1 (0-100 μM) and its two types of degradation products, namely the mixtures of photodegradation products in water (Pw) and the mixtures of photodegradation products in peanut oil (Po) for different time periods (0, 24, and 48 h). After exposure of the HepG2 cells to these compounds for different times and concentrations, the cytotoxicity of Pw and Po decreased approximately 40 and 100% compared with AFB1, respectively. The expression of p53 protein decreased significantly in AFB1-exposed cells, decreased slightly in Pw-treated cells and did not decrease compared to the untreated cells. The results of the in vitro cytotoxicity assay indicate that Pw is less toxic than AFB1, and Po has almost no toxicity, which can be explained by the differences in the chemical nature of the various kinds of the test compounds.

A batch of all beef tallow (BT)-based model shortening (divided into six rectangular block samples) was stored under temperature fluctuation cycles of 5-20 °C until granular crystals were observed. The lipid composition, thermal properties, and polymorphism of the granular crystals and their surrounding materials were evaluated. Furthermore, the isothermal crystallization behavior of two parts noted above was also examined by pulsed nuclear magnetic resonance (pNMR), rheology, and polarized light microscopy (PLM). The changes of nanostructure including the aggregation of high-melting triacylglycerols (TAGs) and transformation into the most stable β polymorph occurred in granular crystals compared with surrounding materials. Concomitantly, a slower crystallization rate with a simultaneous increase in crystal growth led to the formation of large crystals and further aggregated to larger granular crystals when the size ultimately exceeded the sensory threshold.

Beta-D-glucosidase-catalyzed deglucosidation of phenylpropanoid amides of 5-hydroxytryptamine (PAHAs) glucoside in safflower (Carthamus tinctorius L.) seed extracts, including N-(p-coumaroyl)serotonin glucoside (CSG) and N-feruloylserotonin glucoside (FSG), was optimized by response surface methodology (RSM). The Box-Behken design (BBD) was employed to evaluate the interactive effects of independent variables on the deglucosidation rates of CSG and FSG. The variables involved were pH (5.6-6.2), temperature (45-55 degrees C), and enzyme load (2.0-3.0%, relative to the weight of the total substrate). The substrate concentration was fixed at 3.3 g/L on the basis of factorial experiments. The optimum conditions obtained via RSM at a fixed time of 2 h were as follows: pH, 5.9; temperature, 48 degrees C; and enzyme load, 3.0%. Under these conditions, the actual deglucosidation rates of CSG and FSG were 75.5 and 42.2%, respectively, which agree well with the predicted values (75.3 and 41.9%) by RSM. The final incubation time (10 h) was determined by the time course of the deglucosidation under the above-mentioned optimum conditions, which gave the deglucosidation rates of both CSG and FSG above 90%. Simultaneously, 2-hydroxyarctiin, a typical cathartic beta-glucoside, was also removed by 80.3%.

Comparative studies of lipase-catalyzed hydrolysis of soy oil takes place at the interface between the oil and the aqueous solution in solvent-free system were carried out in shaking bath and in ultrasonic bath. The interfacial area between the oil phase and the aqueous phase influences the rate of hydrolysis. Compared to shaking bath, ultrasonic shaking was found to be a more effective procedure to disperse the oil in water. Larger interfacial area and smaller drop size could be obtained in ultrasonic bath. The initial rate of hydrolysis was increased with the increasing of interfacial area. In ultrasonic bath, the highest initial rate of reaction was obtained with the oil volume fraction of 0.7, which was in accord to the highest interfacial area obtained with the oil volume fraction of 0.7, when the ultrasonic power was 1.64 W/cm2. The higher initial rate of hydrolysis was 161 mol/m3 min. The ultrasonic bath was a useful way to disperse soy oil in water to obtain a larger interfacial area, which caused the higher initial rate of soy oil hydrolysis in the solvent-free system.

Comparative studies of lipase-catalyzed hydrolysis of soy oil in solvent-free system were carried out in shaking bath and in ultrasonic bath. A suitable ultrasonic power of 1.64 W cm−2 was determined to guarantee satisfactory hydrolysis extent and lipase activity. The influence of temperature, pH, enzyme concentration and water/oil ratio was investigated subsequently. Compared with that in shaking bath, optimum temperature and inactivation temperature of lipase in ultrasonic bath were about 5–10 °C higher, while pH effect in ultrasonic bath was similar; ultrasound also led to a smooth increase of reaction rate at relatively higher enzyme loading and less use of water to saturate hydrolysis substrate. In optimum conditions, the overall hydrolysis reaction rate in the ultrasonic bath process was above 2-fold than that in the shaking bath process.

The removal of water-soluble Reactive Red MF-3B from aqueous media by sonication-surfactant-modified attapulgite clay was studied in a batch system. The surfactant used was octodecyl trimethyl ammonium chloride (OTMAC). Adsorbent characterizations were investigated using X-ray diffraction, infrared spectroscopy, and surface area analysis. The effects of pH, contact time, initial solute concentration, adsorbent dose, and temperature on the adsorption of Reactive Red MF-3B onto modified clay were investigated. On the basis of kinetic studies, specific rate constants involved in the processes were calculated and second-order adsorption kinetics was observed in the case. Film diffusion was found to be the rate-limiting step. Reactive Red MF-3B adsorption was found to increase with increase temperature. The Reactive Red MF-3B equilibrium adsorption data were fitted to Freundlich and Langmuir isotherm models, the former being found to provide the better fit of the experimental data. Thermodynamic parameters were calculated. From the results it can be concluded that the surfactant-modified clay could be a good adsorbent for treating Reactive Red MF-3B-contaminated waters.

The potential of octodecyl trimethyl ammonium chloride (OTMAC)-modified attapulgite (AT) for phenol adsorption from aqueous solutions was studied. The comparison of natural AT and modified AT showed that it is possible to utilize the sonication-modified OTMAC-AT in the treatment of phenol-contaminated wastewaters. Batch sorption studies were carried out to evaluate the effect of contact time, shaking frequency, temperature and the amount of AT. The results showed that in a lab-scale reactor, at room temperature, with an amount of the modified AT added (2.5 g), and a shaking frequency of 140 rev/min, the adsorption rate of phenol could be 60.4% for a duration of 60 min. The sorption kinetics were described by a pseudo-second-order model, and the values of k and q(e) were 1.367 mg/ig min and 0.7901 ig/mg, respectively. The analysis of equilibrium data showed that the Freundlich isotherms were found to be applicable for the adsorption equilibrium data. K and 1/n were estimated to be 14.53 and 0.8438, respectively.

Purpose : To investigate the effects of CaCl2 on the preparation of low-fat spreads from buffalo and cow butter Methods : Buffalo and cow butter-based low-fat spreads (B-LFS and C-LFS) were treated with CaCl2 (0, 0.02, 0.04, 0.06, and 0.08%) at pH 5.5 and stored at 4°C. They were sampled after 3, 30, 60, and 90 days, and analysed for sensory, morphological, rheological, and melting properties using a 9-point hedonic scale, digital camera, texture analyser TA-XT 2i, Physica MCR 301 rheometer, and differential scanning calorimeter, respectively. Results : Sensory evaluation results showed that control samples were the best of all the treatments; additionally, no phase separation was found in samples treated with 0, 0.02 or 0.04% CaCl2, but separation occurred with 0.06 and 0.08% CaCl2. Generally, hardness and viscosity of samples decreased with increasing CaCl2 concentrations; however, these parameters increased during storage. Increasing CaCl2 concentrations didn’t affect the melting profiles of the spreads, but the parameter varied for B-LFS during storage. Furthermore, the temperature range of the high melting zones of the BLFS samples was greater than that of C-LFS samples. Conclusion : Sensory, morphological, and rheological properties were affected by CaCl2 concentrations but there were negligible effects on the melting behaviour of the spreads. Keywords : Buffalo butter, Cow butter, Calcium chloride Low-fat spread, Sensory, Morphology, Melting