Roasting with superheated steam as the medium are used to obtain gelatinized rice for “green” Chinese wine brewing. The microstructure, pasting properties and starch crystal of rice are determined. That can learn the change in rice during the roasting process is considered the basis to optimize the operating parameters and enlarge the fluidized bed. It is found that the whole process can be divided into two stages, i.e., heating and puffing, with their demarcation point occurs at 20 seconds to 25 seconds after the rice is heated. Heating is a key stage of the processing that is characterized by rapid heat transfer and significant changes in the molecular structure of rice. The temperature of the rice starch needs to be controlled to prevent thermal decomposition and abiotic browning at puffing stage. Through numerical simulation analysis of rice temperature changes in the roasting process, it was found that the two stage strategy is the best mode of roasting process, and standard temperature control curve was put forward as rice temperature control reference during roasting. The comparison between air and superheated steam as two different media shows that the gelatinization effect of rice is practically the same given the same fluidized state, although superheated steam exhibits a slight advantage.
The optimal initial gas composition (CO2, O2 and N2) and its effects on quality and shelf-life of Pacific white shrimp (Litopenaeus vannamei) under controlled freezing-point storage at −0.8°C was determined through microbial flora, pH, total volatile basic nitrogen (TVB-N), exudates and sensory analyses. Pacific white shrimp under gas to product ratio of 3:1 and gas composition spanning the whole area from 0 to 100% based on a simplex centroid mixture design were analyzed after 2, 4 and 6 days of storage. Mesophilic and psychrotrophic bacteria counts, pH and TVB-N contents decreased and formation of exudates increased with increasing of CO2 levels, but odor and appearance scores decreased and mesophilic and psychrotrophic bacteria counts, pH and TVB-N contents increased in the shrimp with decreasing CO2 and increasing N2 concentration. Besides, low O2 levels could favor the odor of raw shrimp. Finally, The optimum gas composition for modified atmosphere packaged Pacific white shrimp under controlled freezing-point storage at −0.8°C was determined to be 75%CO2, 10%O2 and 15%N2, and it could give the most suitable formation of exudates and lowest TVB-N and inhibit the growth of microbial flora; and at the same time maintain high odor and appearance scores in packaged Pacific white shrimp, and the shelf-life was extended to 11 – 12 days, which would be obviously beneficial for the exploitation of quality control, shelf-life extension and development of active packaging on shrimps.
The practical usage of UV-C to decontaminate fruits has been limited by the difficulty applying a uniform dose to complicated shapes. Simulation of UV-C radiation treatment was investigated in this study to find the optimal treatment conditions. A setup of strawberries being placed on a UV-transmittable film with radiation sources from the top and bottom was proposed. A 4-lamp model with a horizontal distance of 300 mm between the lamps was found to yield the most uniform dose distribution, with mean radiation intensity of 2.00 W m−2. For this configuration, the treatment time required to achieve one log inactivation of Cladosporium cladosporioides and Penicillium digitatum spores were 3 min 46 s and 1 min 36 s, respectively. Radiation simulation in combination with the inactivation model has been shown to be a useful tool for the optimization of the UV-C inactivation process.
Japanese radish and potato samples were preheated at 60 – 70°C for 10 min and maintained at 20°C for 0 – 7 h to control the changes in hardness. The slopes of the first order plots for softening and the Arrhenius plots of the softening rate constant were linear. The softening rate constants of Japanese radish and potato were reduced to 18 – 49% and 23 – 50%, respectively, compared to the fresh vegetables. The optimum cooking times of Japanese radish and potato samples with respect to hardness, calculated based on the softening rate constants, were 1.9 – 6.7 and 1.5 – 4.0 times longer, respectively, compared to fresh samples. To prevent browning and the elution of soluble components, samples were vacuum-packed, then pretreated, heated and subjected to sensory evaluation. All samples were evaluated for optimum hardness.
The aim of the present work was to develop a multimethod for the analysis of five flavonoids in G.biloba leaves. The selected flavonoids were rutin, quercetin 3-D-galactoside, baicalin, isorhamnetin and rhamnetin. Leaf extraction was sonicated by using ethanol. The extract was passed through solid-phase extraction columns. Then, the extract was analyzed by high-performance liquid chromatography coupled in line with mass spectrometry. Calibration was carried out over the concentration range of 0.5 to 50 mg/L. The calibration data presented high correlation coefficients (>0.99). The limits of detection were 4.7, 5.3, 9.7, 6.9 and 12.9 µg/L for rutin, quercetin 3-D-galactoside, baicalin, isorhamnetin and rhamnetin, respectively. Mean recoveries ranged from 66% to 72% for the HPLC–MS analysis. Reproducibility was estimated by the relative standard deviation (RSD) which ranged between 2.21 and 3.93%. Five flavonoids were found to be present in G.biloba leaves. The developed method was readily applied to quantify the flavonoids in some commercially available G.biloba leaves.
Optimum conditions for chromatographic separation, at 30µC, of galactose, tagatose, and talose were determined by investigation of the effects of the counter-ion form of cation-exchange resin and the ethanol content of eluent on the distribution coefficients of the monosaccharides onto the resin. Resin in the K+ form with a divinylbenzene content of 8% was found to be most suitable for the separation. The distribution coefficients of all the solutes on the resin were increased as the ethanol content of eluent increased.
A turmeric and roasted soybean flour mixture (TRSF) was successfully fermented in solid-state using Bacillus subtilis HA and Lactobacillus plantarum K154. The co-fermentation was optimized using the turmeric mixture (turmeric: RSF=1:1), 5% MSG, and a 2-fold volume of water. The TRSF fermented by B. subtilis HA showed a consistency of 1.23 Pa.sn and 3.57% (w/w) mucilage. The co-fermented TRSF exhibited pH 5.94 and 1.94% acidity after the second lactic acid fermentation. The viable cell counts of Bacillus sp. and Lactobacillus sp. were 4.50 × 107 CFU/g and 8.00×109 CFU/g, respectively. In addition, the co-fermented TRSF exhibited a higher GABA content (1.78%) than that of the single strain-fermented TRSF. Serial co-fermentation using two bacterial strains can thus provide novel turmeric-based ingredients fortified with γ-PGA, GABA, peptides, and probiotics.
Ten pigmented potato cultivars native to China were investigated for an evaluation of differences in total anthocyanin content (TAC), composition of individual anthocyanidins, total phenolic content (TPC) and antioxidant activity (AA) between peel and flesh of the tubers. On average, TAC, TPC and AA in the peel were 15.34 times, 7.28 times and 5.75 times higher than in the flesh, respectively. High positive correlations between TAC, TPC and AA were observed. Types and contents of anthocyanidins in the peel were more than in the corresponding flesh, but they had the same dominant anthocyanidins. Results showed peel of pigmented potato tuber can be used as an important source material in production of natural pigments and natural antioxidants.
The anti-inflammatory effects of fucoxanthin (Fx) were investigated in vivo and in vitro. When mouse ear swelling was induced by three sensitizers, arachidonic acid, 12-O-tetradecanoylphorbol-13-acetate and oxazolone, both percutaneous and oral administration of 150 nmol/mouse of Fx suppressed the effects, similar to a typical natural inhibitor, epigallocatechin gallate (EGCG). The inhibitory effects of Fx, and its metabolite fucoxanthinol (Fxol), on inflammation-related enzymatic activities [phospholipase A2 (PLA2), cyclooxygenase (COX)-2, lipoxygenase, and hyaluronidase (HA)] were evaluated to elucidate the mechanism of suppression of mouse ear swelling. Both Fx and Fxol inhibited PLA2, COX-2, and HA activities to a greater extent than EGCG. Moreover, they suppressed mRNA expressions of PLA2 and COX-2 in rat basophilic leukemia-2H3 cells. These results suggest that the suppressive effects of Fx and Fxol on mouse ear swelling were due to the inhibition of enzymatic activities and mRNA expression.
Proteins contained in the green leaf mucus of Japanese bunching onion (Allium fistulosum L.) were isolated by ammonium sulfate precipitation and separated by hydrophobic interaction chromatography. The mucus proteins had an enhanced effect on tumor necrosis factor (TNF)-α production in the RAW 264 murine macrophage cell line. Protein composition was analyzed by SDS-polyacrylamide gel electrophoresis and N-terminal amino acid sequencing. The effect on RAW 264 cells was mainly attributed to mannose-binding lectin and thaumatin-like proteins, which occupied 34% of the mucus proteins. Other major proteins contained in the mucus showed homologous amino acid sequences to those of lachrymatory factor synthase, β-1,3-glucanase, 2S albumin precursor, and pathogenesis-related protein 4. Protein composition ratios in the mucus of 13 cultivars of Japanese bunching onion were also examined. Taken together, the green leaf mucus of Japanese bunching onion may be a possible source of various bioactive proteins.
The effect of fatty acids on the characteristic flavor obtained from the Maillard reaction is of particular interest today. Chicken fats were respectively heated at 7 temperatures with an interval increment of 20°C within 60–180°C, while non-heated chicken fat was as a control. Thirteen kinds of fatty acids were identified by gas chromatography-mass spectrometr. (GC-MS). These fatty acids were divided into 3 categories including 7 saturated fatty acids (SFA), 3 monounsaturated fatty acids (MUFA), and 3 polyunsaturated fatty acids (PUFA). Fifty-two kinds of aroma compounds were detected from lipid-Maillard reaction products (MRPs). Analysis of variance (ANOVA) statistical analysis indicated the significant difference (p < 0.001) in six sensory attributes (fatty, meaty, roasty, off-flavor, fresh and overall odor) of MRPs. Partial least square regression (PLSR) was used to detect positive correlation among fatty acids, volatile compounds and sensory attributes. The result showed that 100°C sample (S-100) was correlated with overall flavor and MUFA.
Mung bean sprout turns brown during cold storage. Here we cloned phenylalanine ammonia-lyase (PAL) mRNA and examined its expression during cold storage. A PAL cDNA of mung bean encoding 715 amino acids was cloned, which showed high homology to PAL genes of Fabaceae plants and had a highly conserved PAL motif including the active site (Ala-Ser-Gly). The expression of PAL mRNA increased during cold storage of mung bean sprout. The increase in expression was inhibited by the heat-shock treatment of mung bean sprout before storage. trans-Coumaroyltartronic and trans-caffeoyltartronic acids, the major substrates of polyphenol oxidase in mung bean sprout increased during cold storage. These results show that the PAL expression and biosynthesis of phenolics are essential for enzymatic browning of mung bean sprout during cold storage.
The effect of preservative liquid on the physicochemical properties of Mozzarella cheese during storage was examined. Mozzarella cheese was analyzed 2 weeks after storing in liquid composed of 0–0.2% citric acid, 0–2% sodium chloride, and 0–1% calcium chloride dihydrate. The addition of citric acid and sodium chloride to the liquid increased the moisture content and decreased the hardness of cheese. On the other hand, cheese became harder as the calcium chloride concentration increased. Additionally, citric acid was the main cause of skin formation on the surface of cheese. These results indicate that changes in the combination and concentrations of compounds dissolved in the preservative liquid significantly influence the physicochemical properties of Mozzarella cheese. Thus, the selection of preservative liquid could be one of the important factors determining the product quality.
This paper presents a study that was performed for rapid and noninvasive detection of waxed chestnuts using hyper-spectral imaging. A visual near-infrared (400–1026 nm) hyper-spectral imaging system was assembled to acquire scattering images from two groups of chestnuts (waxed and non-waxed chestnuts). The spectra of the samples were extracted from the hyper-spectral images using image segmentation process. Then multiplicative scatter correction (MSC) was conducted to preprocess the original spectra. Effective wavelengths were selected to reduce the computational burden of the hyper-spectral data. Using the seven effective wavelengths that were obtained from a successive projections algorithm (SPA), three calibration algorithms were compared: partial least squares regression (PLSR), multiple linear regression (MLR) and linear discriminant analysis (LDA). The best model for discriminating between waxed and non-waxed chestnuts was found to be the MSC-SPA-MLR model.
Molecules involved in skin function are greatly affected by nutritional conditions. However, the mechanism linking amino acid (AA)s with these alterations is not well understood. We examined the effects of an AA deficiency on hyaluronan synthesis in human dermal fibroblasts. A deficiency of all AAs or of valine, leucine, isoleucine, threonine, methionine, cysteine, phenylalanine, tyrosine, tryptophan, lysine, arginine, histidine, or glutamine significantly decreased hyaluronan levels in the culture supernatant. The deficiencies of all AAs, valine, leucine, cysteine or glutamine tended to decrease hyaluronan synthase 2 mRNA levels in human dermal fibroblasts. The present study would contribute to the elucidation of the mechanisms underlying the effects of AAs on skin function.
Porcupine liver was an important source of protein, fat, and vitamins, and was of high economic and food value. But its stronger off-flavor which occurred during cooking was an impediment to consumption of liver products. In this study, the volatile compounds of porcupine liver were analyzed by headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). Results showed that hexanal (grassy), (Z)-2-heptenal (fishy), (E)-2-octenal (cardboard-like), 1-octen-3-one (metallic), and 1-octen-3-ol (mushroom-like) were responsible for the off-flavors of porcupine liver. The effects of removing off-flavors were compared by embedding with β-cyclodextrin (β-CD) and fermentation with yeast. Results indicated that fermentation with yeast was better and both the number and area ratio of volatile compounds in porcupine liver decreased with the addition of yeast. Taken together, the off-flavors of porcupine liver were removed by fermentation with the yeast effectively.
The chitosan-based active films were developed by incorporation of cinnamon essential oil (CEO, 10 g/L), pomegranate peel extract (PPE, 10 g/L) and CEO (10 g/L) + PPE (10 g/L) and their physical, antioxidant and antibacterial properties were investigated. Incorporation of CEO and CEO + PPE into the films significantly decreased the water vapor permeability. Incorporation of CEO, PPE and CEO + PPE into the films decreased the transparency, but significantly increased the antioxidant activity. Incorporation of CEO and CEO + PPE exhibited significant antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, the antibacterial activity against the Staphylococcus aureus in the film incorporated with CEO and PPE was significantly higher than that incorporated with CEO or PPE alone, suggesting that there is a synergistic action between CEO and PPE.
We examined the dynamics of water-soluble pectin (WSP), specifically the content and molecular weight distribution, in tea leaves and tea infusions in relation to steaming time during unrefined tea processing. It was revealed that the fraction of higher-molecular weight (MW) WSP in tea leaves was infused at the beginning of unrefined tea processing at all steaming times, and lower-MW WSP was not infused during any processing steps. Moreover, by increasing steaming time, the increase of higher-MW WSP content in tea leaves was reflected by the increase in WSP content of corresponding size in the tea infusions.
Oxygen radical absorbance capacity (ORAC) is a method for evaluating antioxidant capacities of both hydrophilic (H-ORAC) and lipophilic compounds (L-ORAC). In this study, we evaluated the antioxidant capacities of eight herbs (Italian parsley, coriander, celery white, watercress, rocket, mustard green, basil, and corn salad) by ORAC. Basil showed the highest antioxidant capacity among the herbs assessed in this study. The harvest season affected both the H- and L-ORAC values of the herbs, except for the H-ORAC value of Italian parsley. The ratios of H- to L-ORAC values of the herbs ranged from 36 – 86%. Total polyphenol contents of herbs were positively correlated with H-ORAC values, and were also affected by harvest season. We found that isoquercitrin and rutin but not ferulic acid contributed to the seasonal change in the H-ORAC value of basil.