The style of wine, characteristics(balance among color, aroma and taste) and personality (optimal quality) are the important expression form of wine typicality. Wine style is affected by many factors. The natural factors (variety, climate and soil conditions, ecological conditions), human factors (cultivation, harvesting, brewing mode) affecting wine style were reviewed, in order to provide theoretical guidance for the style of wine.
Monascus pigments are a kind of natural, safe and nutritious food coloring and have a good colorability and multiple functional activities. Therefore, Monascus pigments have good application prospect in food, medicine and other industries. In this paper, the components, physico-chemical properties and biological activity of Monascus pigments were introduced, research and application status were summarized, which aimed to provide theoretical basis and reference for further research of the function of Monascus pigments
In recent years, blueberries are used in beverage processing due to its high nutrition and health care value. At present, in addition to fruit juice beverage, the study of blueberry beverage was mainly on fermented beverage such as lactic acid bacteria beverages, vinegar drinks, compound beverage. This paper summarized the research on blueberry fruit beverage, milk beverage, vinegar drinks, and compound beverage, aiming to provide reference for the research and development of the blueberry beverage.
Saccharomyces boulardii is the only strain of yeast as clinical probiotic drugs for the treatment of intestinal diseases. As a microecology preparation, in order to ensure its biological effect, it must be able to maintain a certain number of viable bacteria in the gastrointestinal tract. Research showed that low pH was the most important factor affecting S. boulardii survival rate in the gastrointestinal tract. To improve the survival rate of S. boulardii in low pH condition, atmospheric and room temperature plasma (ARTP) was used for S. boulardii mutagenesis. Finally, three mutant stains with thelow pH-resistant were selected. The results of stability of the mutant strains resistant to low pH showed that after 20 times generation, mutant YB-3 had good genetic stability and its survival rate was 51.79%. In 5 L fermentor, the high density cultivation conditions of mutant YB-3 were optimized. The dry cell weight of S. boulardii obtained was 58.79 g/L, which was increased by 55.52% than that of the original strain.
Effects of different factors on the growth of dual-species biofilm, which was formed by the most common foodborne pathogenic bacterial Staphylococcus aureus and Escherichia coli, were studied by microtiter-plate method. The results showed that S. aureus and E. coli formed high quality biofilms at 25 ℃ or 30 ℃ in 0.8% TSB or BHI medium. The addition of glucose, lactose, maltose, and sucrose improved the growth of the dual-species biofilm, respectively. The formation ability of dual-species was significantly inhibited by adding sodium chloride more than 8%.
In order to protect superior yeast strains from traditional cheese of Kazak in Tacheng region of Xinjiang, 44 yeast strains were isolated from 10 samples of traditional cheese. The isolated strains were identified by colonial morphology, physiological and biochemical characteristics identification and 5.8S rDNA sequence homology analysis. Five species were identified, including 34 strains of Pichia kudriavzevii, six strains of Torulaspora delbrueckii, two strains of Kluyveromyces lactis, one strain of Kluyveromyces marxianus and one strain of Pichia fermentans. Results showed that the yeasts in traditional cheese of Kazak were different with that in other regions, and had its unique resources.
There were significant differences in raw material, microorganism and brewing technology between Cantonese-style soy sauce and Japanese-style soy sauce. The correlation of the physicochemical properties and sensory evaluation was analyzed in detail. Results showed that the typical flavor of fermented soybean was rich in Cantonese-style soy sauce, whereas the aromatics of ester and alcohol and sweet were dominant in Japanese-style soy sauce. The analysis of amino acids showed that the free amino acids content in Japanese-style soy sauce (5.903 g/100 ml) was higher than that in Cantonese-style soy sauce(5.220 g/100 ml), but no significant difference of relative contents of amino acids was observed (P＞0.05). Furthermore, 134 aroma compounds were identified in soy sauce by GC-MS, the main aroma compounds in Cantonese-style soy sauce were esters 25.39%, alcohols 25.23%, acids 13.51%, ketones 4.24%, aldehydes 2.57%, phenols 0.31% and alkanes 28.75%, whereas the main aroma compounds in Japanese-style soy sauce were esters 56.02%, alcohols 21.11%, acids 5.92%, ketones 3.42%, aldehydes 0.69%, phenols 0.15% and alkanes 12.69%. The types and quantities of aroma compounds created the flavor discrepancy of Cantonese-style soy sauce and Japanese-style soy sauce.
The effect of different fumigation processing (steam fumigation and charcoal fumigation) and the processing conditions (temperature and time) on ligustrazine and acrylamide content was studied. The results showed that the steam fumigation can accelerate Maillard reaction rate than charcoal fumigation, the ligustrazine and acrylamide content increased with temperature rising and time prolonging during fumigation, acrylamide generation required higher fumigating temperature (above 100 ℃) than ligustrazine. Whether steam fumigation or charcoal fumigation, acrylamide was not detected at 90 ℃ fumigating to 5 d, which indicated that low temperature fumigation (below 90 ℃) was helpful to avoid acrylamide production. On the premise of low temperature fumigation, compared with charcoal fumigation, steam fumigation not only avoided acrylamide generation, but also facilitated the formation of ligustrazine and brown degree. The steam fumigation technology has a great potential for popularization and application.
Using cider wine fermentation mash containing 7%vol alcohol as domestication medium, the introduced strain Acetobacter pasteurianus 20056 was domesticated and the mutant strain was screened. By UV mutagenesis, results showed that the optimal mutagenesis condition was mutation time 40 s, mutation distance 40 cm and cell dulition 10-5. Under the conditions, the cell lethality reached 82.15%. Fifteen mutant strains were preliminarily screened, through UV mutation effect, acid production experiment, and qualitative experiment, three positive mutant strains UV-3, UV-6 and UV-11 were screened. Compared with the original strain, the acid production of the mutant strain improved 20.45%, 23.73%, 24.61%, respectively. The peak ADH enzyme activity was 2.7, 3.5, 3.7 times of the original strain. Results showed that UV mutation improved alcohol conversion ability of the cider wine fermentation mash effectively, and it provided a simple and efficient breeding method.
On the basis of single factor experiment, the precursor of Agaricoglyceride A (dichloride anisic acid, methanol, glycerin) was added and the precursor addition was optimized in Ganoderma lucidum liquid-state fermentation mycelium. Agaricoglyceride A content was detected by HPLC- ELSD. As a result, dichloride anisic acid 75 mg/L, methanol 1.5 ml/L and glycerin 1.5 ml/L was the optimal addition. The actual value of Agaricoglyceride A was 21.09 mg/L, which was increased by 25.31% compared with the one without any precursor addition.
The flavor compounds in Jinsha Baijiu(liquor) were extracted by headspace-solid phase micro extraction(HS-SPME) and analyzed by GC-MS. Using the 26 common peaks as the characteristic fingerprint peaks of Jinsha Baijiu, and the research method of the fingerprint of Jinsha Baijiu was established. The similarity of the fingerprints of 20 samples including Jinsha Baijiu and the control was evaluated by included angle cosine method. The results showed that the similarity of fingerprints was more than 99% between Jinsha Baijiu and standard, and less than or equal to 92% between other brands Baijiu and standard, which indicated that the established fingerprint could be used to distinguish Jinsha Baijiu. The similarity of fingerprints was more than 99% between the Baijiu and standard, the Baijiu could be identified as Jinsha Baijiu.
In order to remove the fermentation acid on the inhibition of normal growth of heterotrophic Chlorella sp., the coupling technology of heterotrophic chlorella fermentation and resin adjusting pH process was put forward. The effects of addition of resin varieties, adding time and adding amount on the fermentation process were investigated. It was found that adding the resin Lx-300C by 8 g/L could regulate the pH in neutral, the number of cells reached 7.5×108 cell/ml, which was the same as that of the blank group. After fermentation, the weight of the fermentation broth was 5.59% higher than that of the blank group, the resin can be used repeatedly for four times.
Cultivable strains were isolated and purified from Jiuqu. 18S rDNA identification was conducted and the total sugar, alcohol, total acid, and amino acid nitrogen content was determined. Results showed that five mould strains isolated from Jiuqu were FJ-M-1, FJ-M-2, FJ-M-3, FJ-M-4, FJ-M-5. After identification, FJ-M-1 and FJ-M-5 were similar with Mucor JN974020, and the similarity was 98%. FJ-M-2 was similar with Mucor KF805740, and the similarity was 99%. FJ-M-3 was similar with KF805739, and the similarity was 99%. FJ-M-4 was similar with Pilaira anomala, and the similarity was 99%. For nutrient analysis of fermented products, the total sugar content increased to the maximum of 246 g/L at 60 h, and then decreased. The total acid content increased gradually, and reached maximum of 7.6 g/L at 84 h. Amino acid nitrogen content increased and then tend to stable, and it reached maximum of 0.3 g/L at 84 h. The alcohol content was stable after 48 h, and it reached maximum of 8.0%vol.
The fermentation liquid of Paenibacillus campinasensis xy-7 was separated and purified by ammonium sulfate salting-out, Sephadex G-50 gel filtration and DEAE Sepharose Fast Flow ion-exchange column chromatography. The purified xylanase was obtained, the purification multiple was 26.36 and recovery rate of the enzyme was 5.13%. The electrophoresis result of SDS-PAGE was single band and mass of molecule was 24.5 ku. The results of enzymatic property showed that the optimal reaction temperature of xylanase was 60 ℃ and the optimal pH was 8.0. The enzyme could be activated by Fe2+ and K+, but inhibited by Zn2+ and Cu2+. With beech xylan as substrate, the Km was 4.733 mg/ml and the Vm was 315.85 μmol/(min·mg).
Using the Monascus purpureus FBKL3.0018 screened from medium temperature Daqu as research object, the esterification enzyme-producing technology conditions of submerged fermentation were optimized. By single factor experiments and orthogonal experiments, the optimum components of culture medium were determined as maltose 5%, beef extract 2% and MgSO4 0.04%, and the highest enzyme activity was up to 116.32 U/ml, which was 45% higher than that of before optimization. The optimum culture conditions were inoculum 10%, culture temperature 32 ℃, time 5 d and shaker speed 160 r/min, and the highest enzyme activity was up to 153.34 U/ml, which was 32% higher than that of before optimization.
Using Kunlun snow chrysanthemum in Xinjiang as the raw material, snow chrysanthemum polysaccharides (KSCP) were extracted by ultrasonic-assisted method. The extracts were purified by deproteinization, decoloration, dialysis, DEAE-52 chromatography column and SephadexG-100 gel chromatography column, and two polysaccharide components (KSCP1 and KSCP2) were obtained. The purity of polysaccharide components were identified by ultraviolet spectrum analysis, freezing and thawing method and SephadexG-100 gel column chromatography. Meanwhile, the range of KSCP molecular mass and monosaccharide composition were analyzed by gel permeation chromatography(GPC) and GC-MS. The results showed that KSCP1 and KSCP2 were both single composition. KSCP1 was composed of four kinds of monosaccharide including glucose, arabinose, galactose and xylose, the molar ratio was 10.53∶5.02∶4.96∶1, and the range of molecular mass was 8 200-8 700 u. KSCP2 was composed of three kinds of monosaccharide including glucose, arabinose and galactose, the molar ratio was 1∶2.78∶5.07, and the range of molecular mass was 6 100-6 500 u.
The volatile components in stinky tofu brine at different fermentation stages were extracted by SPME and analyzed by GC-MS. The changes trend of volatile components in stinky tofu brine during the whole fermentation was studied. 122 compounds were identified, including 18 alcohols, 9 organic acids, 24 esters, 20 ketones, 6 aldehydes, 3 phenols, 30 alkanes, 9 alkenes, 3 indole, and 30 other compounds. The results showed that 3-methylindole was detected during the whole fermentation and it was the main factor for generating stinky tofu smell fragrance.
Physalis pubescens enzyme was prepared by different fermentation technologies(including natural fermentation, yeast-Lactobacillus plantarum inoculated fermentation in order, yeast-Lactobacillus plantarum inoculated fermentation at one time), the reducing power, scavenging capacity to DPPH radical and SOD activity were detected during fermentation, and the effect of different fermentation technologies on the antioxidant activities of P. pubescens enzyme was studied. The results showed that the P. pubescens enzyme that got from different fermentation technologies had strong antioxidant activity. Compared with the natural fermentation after 22 d, the reducing power of artificial inoculation fermentation improved by 30.74%, 27.27% and 39.83%, respectively, the scavenging capacity to DPPH improved by 22.94%, 15.49% and 26.74%, respectively. Furthermore, the SOD activity improved by 52.93%, 39.37% and 56.80%, respectively. The enzyme of yeast-L. plantarum inoculated fermentation at one time had the optimal antioxidant activity, the reducing power was up to 1.051, the scavenging capacity to DPPH was up to 30.97% and the SOD activity was up to 409.52 U/ml.
The nattokinase NKII was separated and purified by hydrophobic chromatography. The purified enzyme showed a single protein band in the SDS-PAGE and the molecular weight was 28 ku. The enzyme overall yield was 56.51%, the purification factor was 17.90 and the specific activity of NKII was 48 407.77 IU/mg. The activity of NK was detected by the methods of fibrin plate and chromogenic substrate method. Results proved that two methods had high correlation. When S-2251 was used as substance, the kinetic parameter Km was 0.379 6 mmol/L and Vm was 0.059 8 mmol/(L·min), Ca2+ and Mg2+ showed significant effect on enzyme activity stability.
Kudzu root juice was fermented by lactic acid bacteria and yeast. By the analysis and detection of the total flavonoids, γ-aminobutyric acid (GABA), free amino acid, organic acid, ethanol and volatile components during the Kudzu root juice fermentation, the change rule of the nutrition and flavor components before and after fermentation was researched. The results showed that the total flavonoids content(0.71 g/L), GABA content (3.64 g/L) and total essential amino acids content in Kudzu root juice fermented for 6 d were 17.72%, 279.17% and 65.58% higher than the total flavonoids content (0.59 g/L), GABA content (0.98 g/L) and total essential amino acids content in Kudzu root juice, respectively. The ethanol yield decreased, the lactic acid content increased, and volatile components (aldehydes, alcohols and esters) increased after the fermentation.
The effect of different alcohols on Acetobacter xylinus JMCW-1 was studied. The results showed that different alcohols addition had little effect on the pH of fermentation broth. Residual sugar levels in the broth added ethanol, glycerol, ethylene glycol were much higher than that in control group. Residual sugar levels in the broth added polyethylene glycol first lowered and then increased slightly and subsequently reduced. Residual sugar levels in the broth added polyvinyl alcohol gradually decreased. The OD in the broth added glycol decreased, and the OD in the broth added other alcohols increased. Ethanol, glycerol, and polyvinyl alcohol can increase the yield of bacterial cellulose; the dry weight of bacterial cellulose reached the highest 22.6 g/L with ethanol addition 3.5%, which was seven times of the blank group. Methanol had no significant effect on bacterial cellulose production. Polyethylene glycol and ethylene glycol had a certain inhibition on bacterial cellulose production.
A yeast FY4 with low β-glucosidase activity, fast growth and no-membrane-producing was screened from 23 yeast strains preserved in the laboratory and derived from the natural fermented fruit wine. The yeast FY4 was identified as Saccharomyces cerevisiae by 18S rDNA sequencing analysis. The blackberry wine was fermented by S. cerevisiae. The effects of fermentation temperature, pectinase addition, sugar addition and yeast inoculum on the anthocyanin content in blackberry wine were researched by single factor and orthogonal experiments. In the conditions of yeast FY4 inoculum 2%, fermentation temperature 32 ℃, sugar 14%, pectinase 0.22%, the anthocyanin content in blackberry wine after fermentation was up to (406.31±5.64) mg/L, which was 1.53 times of blackberry wine fermented by commercial S. cerevisiae PHYTHM.nsac at the same conditions.
Using citrus pomace as raw material and Aspergillus oryzae as fermentation starter, kojic acid was produced by liquid-state shake flask fermentation. Using Box-Behnken centrol composite design, the optimal fermentation process of citrus pomace was optimized by response surface methodology. As a result, the optimal fermentation parameters were determined as follows: A. oryzae inoculum 4%, citrus pomace 13 g/100 ml, yeast extract 1.5 g/100 ml, and MgSO4·7H2O 0.05 g/100 ml. Under the conditions, the kojic acid production was the highest of (11.84±1.44) mg/ml.
By the determination of the physicochemical indexes, phenolic compounds content ferric ion reducing antioxidant power, DPPH free radical scavenging activity and hydroxyl radical scavenging activity of the wines, the antioxidant activities of three kinds of fermented sweet potato (including Yuzi 263, Zishuwang and Yushuwang) wines were researched. Results indicated that the total phenols contents in the wines were 247.5 mg/L, 200.5 mg/L and 63.5 mg/L, respectively. The phenolic compounds, ferric ion reducing antioxidant power, DPPH free radical scavenging activity of Yuzi 263 wine and Zishuwang fermented wine were significantly higher than that of Yushuwang fermented wine. And the hydroxyl radical scavenging activity of the wines was significantly higher than that of VC. Results indicated that all wines had a strong antioxidant activity.
Contrasted with potato starch, the physicochemical properties of potato resistant starch prepared with cellulase-pressure thermal treatment were studied. Results showed that potato starch granules were in ellipsoid and smooth. Resistant starch had no granule structure, formed a continuous compact structure, and their surfaces were not smooth. The chemical structure of two kinds of starch was similar but the resistant starch formed more hydrogen bonds. The crystal form of potato starch was type A. Its crystallization degree was 22.82%. The crystal form of resistant starch was type B. Its crystallization was 29.64%. The solubility and transparency of resistant starches were far lower than potato starch and the swelling capacity and water-holding capacity were better than potato starch. The settling speed of resistant starch was faster and settling properties were stronger than those of potato starch. The gelatinization temperature of potato starch were 65.8 ℃ and the peak viscosity could be 10 770 mPa·s. Gelatinization temperature of resistant starch was higher than 95 ℃.
The brewing technology of Guangdong Hakka rice wine was optimized, to improve the gamma-aminobutyric acid (GABA) content in Hakka rice wine. The factors of Chinese yeast, wheat koji, Monascus, water addition, bottling capacity and immersion time were screened by single factor experiment, fractional factorial experiment was optimized by Design-Expert 8.05 software. The results were most affected by bottle capacity and immersion time. Through the response surface optimization experiment on the two significant factors, results showed that the optimal brewing technology was as follows: Chinese yeast 0.5%, wheat koji 0.5%, Monasus 5%, water addition 5% (in raw material quality glutinous rice percentage), bottling capacity 200 g/L and immersion time 30 h. Under the conditions, the GABA content in the Hakka rice wine was 295.79 mg/L, increased 142.89 mg/L compared with the rice wine with traditional technology.
The effect of sodium selenite on nitrite in Osmunda japonica fermentation was investigated. Sodium selenite could reduce nitrite-peak by adding it in the O. japonica with natural and inoculated fermentation. The nitrite peak was lower than natural fermentation and appeared 1 d in advance in the O. japonica by inoculated fermentation. When the fermentation was over at 8 d, nitrite and nitrate content of inoculated O. japonica were lower than that of natural fermentation. Using nitrite content after the end of the fermentation as evaluation index, results showed that the suitable sodium selenite was 0.3 g/L. Maintaining the pH 5.0 by adding Na2CO3 in the O. japonica fermentation, nitrite-peak appeared 1 d in advance, then nitrite reduced from 2.16 mg/kg to 0 at the end of fermentation. When sodium selenite was added 0.10 g/L per time for three times, nitrite-peak appeared at 3 d, and then nitrite reduced from 1.26 mg/kg to 0.34 mg/kg, and nitrate reduced from 0.13 g/kg to 0.032 g/kg at the end of fermentation.
The degradation conditions of cellulose in Cladophora by Penicillium were researched. The effects of the nitrogen sources, ammonium sulfate content, solid-liquid ratio, pH, fermentation temperature and time on cellulose degradation were researched by single factor experiments. The effects of pH, solid-liquid ratio and ammonium sulfate content on protein content, total sugar content and cellulase activity were investigated by L9(33) orthogonal experiments. The optimum degradation conditions were algae powder 3 g/L, solid-liquid ratio 1∶15 (g∶ml), ammonium sulfate 20 g/L, potassium dihydrogen phosphate 1 g/L, magnesium sulfate 0.5 g/L, buffer solution pH 6.0, fermentation temperature 30 ℃ and time 7 d. Under the conditions, protein content, total sugar content and cellulase activity were 12.44 g/100 g, 0.58 mg/g and 4.84 U/g, respectively.
The root-mustard was traditionally produced with high salt, resulting the salt content 15%-20%, too salty and harmful to health. So production and sales was limited to a certain extent. Using the salt content and sensory value as evaluation indexes, the effect of material-liquid ratio, desalination time, desalination temperature and changing the water times on desalting efficiency of high salt root-mustard was researched. The optimum desalination process conditions was material-liquid ratio 1∶3 (g∶ml), time 20 ℃, temperature 15 min and changing the water two times. Under the conditions, the salt content of root-mustard after desalting was 4.12%, and the sensory evaluation was the optimal.
The pachymaran components by biodegradation were analyzed by HPLC with pre-column derivatization. Using Aspergillus niger HS-5 as fermentation strains to conduct liquid-state fermentation, pachymaran was degraded by biodegradation. Pachymaran solid sample was obtained by concentrating crude sugar, sevage purification and vacuum drying. Pachymaran solid sample was analyzed and identified by infrared spectroscopy (IR) and ultraviolet spectroscopy (UV), then using HPLC analysis with PMP column derivatization, by comparison with the peak time of the standard, the monosaccharide composition and contents were determined as follows: mannose 5.463%, rhamnose 8.970%, D-xylose 52.809%.
In order to compare the difference of expression level of the three genes involved with citrinin synthesis under aerobic and anaerobic conditions and discuss the corresponding relationship between yield and expression level of genes involved, high citrinin-producing Monascus MX1 was cultured for 20 d under the aerobic and anaerobic conditions, respectively. The changes of citrinin yield and expression level of genes involved were monitored dynamically. Under aerobic conditions, both the citrinin yield and expression level of genes involved first increased, then decreased, and reached their highest levels on the 8th day. While under anaerobic conditions, the citrinin yield was in a low level and the final yield of citrinin was 40.16% lower than that under aerobic conditions. The expression level of ctnA gene under anaerobic conditions was always lower than that under aerobic conditions, while the expression level of orf7 gene was higher, and the expression level of pksCT gene had no obvious regularity. The results showed that anaerobic conditions could inhibition ctnA gene expression and promote orf7 gene expression to inhibit the synthesis of citrinin, but pksCT gene was not the key gene of citrinin synthesis.
The scavenging rate of quercetin, quercetin-Al and quercetin-B on sodium nitrite was determined by aminobenzene sulfonic acid-hydrochloric acid naphthalene ethylenediamine method. The results showed that quercetin and its quercetin complexes had a certain scavenging activity on sodium nitrite. The scavenging rate of quercetin-Al and quercetin-B on sodium nitrite was significantly higher than that of quercetin. Under the optimal reaction conditions of 0.4 mg/ml scavenging agent addition 1.2 mL, reaction temperature 50 ℃ and temperature 30 min, the scavenging rate of quercetin on sodium nitrite was 25.8%, while the scavenging rate of quercetin-Al and quercetin-B on sodium nitrite were 80.2% and 84.1%, respectively. The scavenging rate of quercetin-B was slightly higher than that of quercetin-Al.
In order to obtain high extraction rate of protein from Grifola frondosa mycelium, the G. frondosa mycelium protein was extracted by ultrasonic wave with the G. frondosa mycelium as raw material. On the basis of single factor experiments, with the extraction rate of protein as the evaluation index, the extraction processing was optimized by orthogonal experiments. The results showed that the optimum extraction conditions were liquid-material ratio 95∶1 (ml∶g), ultrasonic power 600 W, ultrasonic temperature 35 ℃, ultrasonic time 3 min and pH 10.5. Under the conditions, the protein extraction rate was (5.10±0.04)%.
To determine the biological activity of Hovenia acerba sticks polysaccharide (HASP), the extraction process condition of HASP was optimized and the in vitro antioxidant activity of HASP was evaluated. On the basis of single factor test, response surface analysis was used to optimize the extraction process of polysaccharides from H. acerba sticks. The scavenging efficiency of HASP on hydroxyl radical, ABTS radical and DPPH radical were determined, to study the antioxidant activity. The results showed that the optimal extraction conditions were solid-liquid ratio 1∶30 (g∶ml), extraction temperature 80 ℃ and time 2.0 h, and the extraction rate of HASP was up to 2.44%. The in vitro antioxidant activity tests revealed that HASP exhibited high hydroxyl radical, DPPH radical, and ABTS radical scavenging activities, and maximum scavenging rate were 76.2%, 91.3% and 96.8%, respectively.
Using the protein removal rate and polysaccharide loss rate as the evaluation indexes, the effects of deproteinization methods (including Sevag method, enzymatic method and trichloroacetic acid method on deproteinization efficiency of exopolysaccharide from Grifola frondosa were investigated. The results showed that trichloroacetic acid method was superior to Sevag method and enzymatic method. In the condition of the optimum addition of trichloroacetic acid 3%, the protein removal rate and polysaccharide loss rate was 68.40% and 21.11%, respectively. The results of UV spectroscopy scanning showed that G. frondosa exopolysaccharide with deproteinization treatment by trichloroacetic acid method had no obvious absorption peak in the range of 200-600 nm, which indicated that the proteins in crude polysaccharide were almost removed. Trichloroacetic acid method could be used as a kind of effective method of deproteinization in purification of extracellular polysaccharide from G. frondosa .
Supplementation of D-alanine, L-arginine, L-glutamine with different concentration in the range of 160-480 mg/L was added into lychee juice, respectively. The effects of supplementation on the fermentation dynamics, non-volatile and volatile constituents produced during the fermentation of lychee wine were investigated. The results showed that addition of different types and concentrations of amino acids increased the consumption rate of soluble solid contents at different degrees, while shortened the yeast fermentation time, increased total alcohols, and significantly changed acids and esters content. The ethanol content was slightly increased from 10.52%vol in the blank sample to 10.71%vol-11.68%vol in the treatment sample, whereas the glycerol content decreased from 6.33 g/L to 4.17-6.04 g/L, and the acetaldehyde content was also decreased obviously. Different type and amino acid concentration supplement had the different impact on lychee wine.
Using dansyl chloride as pre-column derivation agents, eight kinds of biogenic amines content in wine from 21 regions in Xinjiang was determined by reverse phase high phase liquid chromatography (RP-HPLC). The results showed that the total content of biogenic amines in wine from different regions was significant difference. The total content of biogenic amines in wine from Hotan region was the least (37.16 mg/L), and the total content of biogenic amines in wine from Turpan region was the highest (335.18 mg/L). The types of biogenic amines in wine from different regions were also difference. Spermine content was the highest in biogenic amines, and the average content was 87.37 mg/L. By determination and analysis of biogenic amines content, it could provide the basis for safety and quality of biogenic amines in wine of Xinjiang regions.
A method was established for the determination of capsaicin and dihydrocapsaicin in edible oil by solid phase extraction and LC-MS/MS. The results indicated that the capsaicin showed good linear relationship in the range of 0-100 ng/ml (R2 = 0.998 6), the average recovery was 70.6%-90.5%, and relative standard deviation (RSD, n=3) was 3.1%-8.9%, and the detection limit was 0.03 μg/kg. The dihydrocapsaicin showed good linear relationship in the range of 0-20 ng/ml (R2 = 0.998 8), the average recovery was 71.5%-100.7%, relative standard deviation (RSD, n=3) was 6.0%-13.2%, and the detection limit was 0.006 μg/kg. The method was simple, rapid, accurate and reliable, and it was an effective method for the identification of waste oil and determination of capsaicin in edible oil.
The determination method of mannan and β-glucan content in the yeast cell wall was established by HPLC. The chromatographic conditions were as follows: the chromatographic column Welch Sugar-Ca (7.8 mm×300 mm), mobile phase was pure water, flow rate was 0.5 ml/min, column temperature was 80 ℃, and the signal was detected by refractive index detector. The results showed that at the range of 20-1 000 μg/ml, the content of mannan and β-glucan had a good linear relationship with the peak area. The relative standard deviation of the method was less than 1.15%. The recovery rate was 98%-100%. The method was simple, accurate and convenient, which was suitable for the determination of mannan and β-glucan contents in yeast cell wall.
Taking the advantage of sweetness of orange juice can neutralize the acor of Chaenomeles sinensis, using juice proportion, juice content, sugar content and citric acid content as independent variable. The optimal processing condition was optimized by single factor experiment and response surface methodology as follows: orange juice and C. sinensis juice ratio 6∶1, juice 82%, sugar 6%, and citric acid 0.2%. The optimal stabilizing agent formula of navel orange-C. sinensis juice was further determined by single factor experiment and orthogonal experiment as follows: xanthan gum, CMC-Na and sodium ratio 3∶3∶1, the addition 0.20%. Under these conditions, the precipitation ratio was 0.37%, the sensory evaluation score of the juice was 89, which was significantly higher than other samples.
Using pueraria and glutinous rice in Jingmen area as material, sweet fermented glutinous rice (or Laozao) was fermented by inoculating the sweet fermented rice starter. Using the ratio of glutinous rice and pueraria, starter inoculum, fermentation temperature and time as factors, the fermentation technology of sweet fermented glutinous rice were optimized by single factor and orthogonal experiments. The results showed that the optimum fermentation conditions were determined as follows: the mass ratio of pueraria and glutinous rice 1.0∶1.5, starter inoculum 2.0%, fermentation temperature 30 ℃ and time 3 d. Under the conditions, the sensory score of sweet fermented glutinous rice mixed with pueraria obtained was 85, total sugar content was 35.4%, alcohol content was 3.3%vol, flavonoids content was 4.2 mg/100 ml, and total acid content was 82.3 mg/100 ml (based on citric acid).
