Abstract:With a long time of evolution, life has formed a set of extremely perfect technology to produce nutrients from food materials, and many life activities have the same effect as the existing unit operations of food processing. Therefore, the theory and technology innovation of food processing based on bionics theory and learning from life body have been widely concerned at home and abroad. This paper summarized and analyzed the research cases of food processing technology innovation inspired by human senses, food digestion, nutrient absorption, biosynthesis, biomaterials, bio-mechanisms and bio-forming. The main tasks of bionic development in future food industry were summarized into three aspects. 1) Recognizing life activities:breaking through the limitations of life science research based on the needs of health and production (growth), suggesting that life activities should be re-studied and life phenomena should be re-understood from the perspective of making nutrients needed for normal growth. 2) Deepening the started bionic research work:according to the re-research results of life activities, further study of the bionic technology that had been started, and explored new ideas. 3) Developing new bionic research methods:through comparison, finding out the life activities in animals, plants and microorganisms corresponding relationship with food processing technology, exploiting the never touched bionic research field, and promoting the original innovation in the field of food. This paper once again emphasized the importance of the discipline construction of food engineering bionics.

Abstract:Qingke is a dominant special crop on the Qinghai-Tibet plateau in China. Qingke has been planted for more than 3500 years in the Qinghai-Tibet plateau region with the condition of high cold, hypoxic and harsh environment. It has the advantages of cold and drought resistance, barren tolerance, short growth period, strong adaptability, strong stress resistance, stable yield and easy cultivation. Qingke is the raw material for the production of “Zanba” and Qingke wine. Qingke is rich in nutrients and bioactive ingredients, and has the characteristics of “three high and two low” (high protein, high fiber, high vitamins, low fat, and low sugar). Intake of bioactive substances through diet is crucial to improve human health. Various bioactive ingredients in Qingke could have a positive impact on human body, which is conducive to reducing the incidence of human heart disease, diabetes, coronary heart disease, obesity and other chronic diseases and related metabolic diseases. Therefore, the main bioactive components and physiological functions in Qingke, such as β-glucan, pentosan, dietary fiber, phenolic compounds and vitamin E, were summarized, and the research progress of the main active components of Qingke in recent years was summarized, which might provide reference for the further research on the physiological functions of Qingke and the development of functional foods.

Abstract:Oats, a worldwide cultivated crop, is a whole grain with high nutritional value. It is rich in dietary fiber, proteins, lipids, vitamins, minerals and other nutrients, which serve critical roles in regulating lipid metabolism, reducing blood glucose, improving constipation and other aspects. As a special polyphenol of oats, avenanthramides has attracted much attention for its physiological functions. Studies found that avenanthramides 2c, 2f, and 2p were in higher content of natural oats, which had multiple biological functions and played an important health care role in the prevention and treatment of common chronic diseases. In this paper, the research progress of avenanthramides was systemically reviewed, including chemical structure and biological activities of antioxidation, reducing inflammatory reaction, preventing atherosclerosis, and anti-tumor, and hoping to provide reference for the comprehensive utilization and the development of health care products of avenanthramides in oats.

Abstract:A glycoside hydrolase (GH) 11 family xylanase gene (TaXyn11A) from Trichoderma asperellum was cloned and heterologously expressed in Escherichia coli. The gene had an open reading frame of 672 bp, encoding 223 amino acids. The deduced amino acid sequence shares the highest identity (85.2%) with the GH 11 family xynII (NCBI accession No. B5A7N4.1) from Trichoderma harzianum C4. The crude enzyme was purified by one-step to homogeneity by Ni-NTA with a molecular mass of 24.2 kDa. The recombinant xylanase (TaXyn11A) was biochemically characterized, and the results showed that TaXyn11A was an acidic and mesophilic enzyme, having optimal pH and temperature of pH 5.0 and 50℃, respectively. The stability of the enzyme was between the pH range of 4.0~10.0 and temperature lower than or equal to 45℃, and its half-life at 45℃ was 14.3h. The enzyme was activated by EDTA, Mn²⁺ and Cr³⁺, while strongly inhibited by SDS and CTAB. Analyses for substrate specificities and hydrolysis properties indicated that TaXyn11A exhibited great sensitivity towards oat xylan, wheat arabinoxylan, beechwood xylan and birchwood xylan, with specific activities of 989.6,727.6,706.0 and 484.5U·mg-1, respectively, and the enzyme hydrolyzed verious xylans for 12h to mainly yield xylooligosaccharides with polymerization degree of 2~6. The favorable properties of TaXyn11A may make it a good candidate in xylooligosaccharides production in industry.

Abstract:Glucosamine is widely used because of its diverse biological activity. However, its industrial production requires the hydrolysis reaction with concentrated acid at high temperature. Therefore, an environmentally friendly biocatalytic method is needed to replace the deacetylation of glucosamine by acid hydrolysis. In this study, the deacetylase (CqCBDA) from Cyclobacterium qasimii was screened and was successfully expressed heterologously in the Escherichia coli, which had a high level of soluble protein expression. The purified recombinant CqCBDA had the N-acetylglucosamine deacetylation activity and the specific enzyme activity was 11.5U/mg. The optimal temperature and pH value of CqCBDA was 40℃ and 7.6,while CqCBDA showed high thermal stability below 40℃. CqCBDA has great potential to be applied to the production of glucosamine by enzymatic hydrolysis. This study provides theoretical reference for green manufacturing of glucosamine by the enzymatic approach.

Abstract:agarase plays an important role in the enzymatic preparation of functional agaro-oligosaccharides. However, there are only few studies focused on α-agarases. An α-agarase named OUC-GaJJ96 from Gilvimarinus agarilyticus was cloned, and its enzymatic properties together with hydrolysis products were studied. OUC-GaJJ96 belong to glycoside hydrolase 96 family with a molecular weight of approximately 180 kDa. The gene OUC-GaJJ96 comprised a 3759bp, encoding a protein of 1252 amino acids, with a signal peptide of 26 amino acids at its N-terminal. The enzymatic properties of OUC-GaJJ96 showed that the optimal temperature and pH were 30℃ and 7.0 (Tris-HCl buffer), respectively. The specific activity of OUC-GaJJ96 was 2.68U/mg. The analysis of HPLC and ESI-MS demonstrated that the hydrolysis products of OUC-GaJJ96 were agarobiose, agarotetraose and agarohexaose, in which agarotetraose was the main product. Therefore, OUC-GaJJ96 has potential for the manufacture of bioactive agaro-oligosaccharides.

Abstract:The influence of intestinal microflora on the stability of wine anthocyanins and the relationship between anthocyanin structure and stability were analyzed, which is helpful for understanding the digestion and absorption of anthocyanins and improving bioavailability of wine anthocyanins. Human gut microflora was collected from healthy volunteers and incubated with Cabernet Sauvignon red wine for 24h in vitro. Samples were collected at 0,4, 12, and 24h for high-performance liquid chromatography analysis of anthocyanins. The results showed that gut microflora accelerated the degradation of wine anthocyanins. After incubation with gut microbiota for 24h, the degradation rate of total wine anthocyanins reached 19.10%, which was only 9.57% in control group. The degradation levels of 5 basic wine anthocyanins were all higher than those in control group with no significant difference. Compared with the control group, the concentration of 3 acylated anthocyanins in wine decreased significantly after incubation with gut microflora. The stability of anthocyanins was influenced by their substituents on the B-ring and acyl group on the glucoside. The stability of anthocyanins was decreased with the increasing number of hydroxyl groups on the B-ring, while the stability was increased with the increasing number of methoxyl groups on the B-ring. Acetylated anthocyanins were more stable than that of their corresponding coumarylated anthocyanins. The promoting degradation of anthocyanin by gut microflora was related with the structure.

Abstract:To investigate the effects of characteristic ingredient vanillyl alcohol of Rhizoma gastrodiae on mycelial biomass and exopolysaccharide (EPS) synthesis, different mass concentrations of vanillyl alcohol were added to the Grifola frondosa fermentation system. The EPS production was determined by phenol-sulphuric acid method and the mycelial biomass was recorded. The results showed that a certain mass concentration of vanillyl alcohol could promote the biomass and EPS synthesis of Grifola frondosa. The optimal effect of vanillyl alcohol on the biomass and EPS synthesis of Grifola frondosa was shown at mass concentration of 200 mg/L, which were significantly increased by 21.1% and 19.9% compared to the blank control group (no addition of vanillyl alcohol), respectively (P<0.05). In addition, during the whole fermentation process with vanillyl alcohol, the fermentation began to stabilize on the 13th day, and the biomass and EPS yield were the maximum on the 14th day, which were(1.42±0.01)g/L and (2.10±0.03)g/L, respectively. However, they were both lower than that fermentation with Rhizoma gastrodiae alcohol extract or p-hydroxybenzaldehyde test group. On the 14th day, the content of vanillyl alcohol was decreased by 68.3% in comparison with that on the 0th day. As a characteristic ingredient in Rhizoma gastrodiae alcohol extract, vanillyl alcohol could be used for promoting the mycelial growth and EPS synthesis by Grifola frondosa.

Abstract:A high performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) for determination of selenium speciations (Se(VI), SeCys₂, SeMeCys and SeMet) in Se-enriched foods (Se-enriched protein powder, Se-enriched rice, Se-enriched shiitake mushrooms and Se-enriched yeast, etc.) was developed in this study. Samples were extracted with Tris buffer and hydrolyzed by protease and trypsin, followed by separating on Hamilton PRP-X100 anion exchange column with a mobile phase consisting with V (20mmol/L diamine hydrogen phosphate aqueous solution,pH=6.0)∶V (methanol)=98∶2. Four speciations of selenium were completely separated as achieving the linearity larger than 0.999, the method detection limit reached 25-50μg/kg, and the average recovery rate was 81.37%-93.80% (RSD 2.80%-7.22%). This method was used to detect 4 kinds of selenium morphological compounds in 4 kinds of commercially available selenium-rich foods (Se-enriched protein powder, Se-enriched rice, Se-enriched shiitake mushrooms and Se-enriched yeast). The advantages of this method were simple pretreatment procedure, rapid determination, high accuracy and sensitivity, which provided a method and basis for the evaluation and quality control of selenium in food.

Abstract:Natural food pigments are widely used, and trichromatic pigments can be mixed with different colors according to their concentrations. Traditional color matching methods are highly dependent on experience of color matching, which result in low production efficiency, big variation and poor product quality stability. In this study, according to the characteristic absorption peak of natural food pigments had no change during mixing, and based on the matching method of absorption spectrum, color matching models of multiple linear and neural network were established between the concentration of pigments and the absorption value of the characteristic absorption peak. And the optimal model was selected and tested by errors analysis. The results showed that the prediction accuracy and stability of neural network model were better than those in multivariate linear model, and the color differences between the prediction formula and the original formula were within 3, which could not be distinguished by naked eyes. Thus the neural network models were more suitable for color matching requirements. These results provided theoretical basis for the intelligent color matching of natural food pigments.

Abstract:Based on the thawing loss rate, cooking loss rate, thawing pH, protein solubility, water distribution and other indicators, the effects of 5 different thawing methods on the physicochemical property and microstructure of frozen loach muscle tissue were studied, including thawing with 4℃, room temperature, mobile water, microwave and ultrasonic, and the correlation between the indicators was analyzed. The results showed that there was a significant difference in thawing loss rate of loach muscle tissue thawing with different methods. In comparison with other thawing methods, there was the least influence on thawing loss rate, cooking loss rate, pH and solubility of protein after mobile water thawing. The correlation analysis of each index showed that the solubility of myogen was significantly correlated with other indexes. The microstructure of thawed loach muscle tissues was observed by scanning electron microscope. After thawing, the intramuscular space of loach was enlarged, and the largest space was found after ultrasonic thawing, and microwave thawing resulted in partially protein denaturation. The transverse relaxation time was measured by low-field nuclear magnetic resonance. And it was found that the water state and content of the thawing loach meats changed compared with the fresh sample. Among the five thawing methods, the thawing loss rate and cooking loss rate of water thawing were the least, and the texture characteristics were excellent. Finally, water thawing was the optimal thawing method for frozen loach.

Abstract:In order to explore the quality traits of Takifugu rubripes as sushi-grade seafood, microstructure and biochemical and nitrogenous compounds properties of Takifugu rubripes skeletal muscle were investigated. The muscle protein composition, ATP-related compounds and free amino acids were emphatically explored. The results showed that the skeletal muscle of Takifugu rubripes presented high-protein and low-fat characteristics which were similar with white fish species. And the crude protein was accounted for 86.30% of the skeletal muscle dry basis, while the fat was only accounted for 0.66%. Histomorphological observations revealed that the connective tissue in the Takifugu rubripes muscle was abnormally abundant. Further analysis found that the collagen content was accounted for 4.53% of the muscle dry basis. The results of nitrogen components analysis showed that the content of salt-soluble protein was the highest, accounting for 40.76% of total nitrogen components, followed by the water-soluble protein 25.71%, insoluble protein 13.24% and alkali-soluble protein 5.18%. In addition, the non-protein nitrogen compounds were rich in the Takifugu rubripes muscle, accounting for 15.10% of total nitrogen components. SDS-PAGE analysis showed that the water-soluble fraction and salt-soluble fraction had a wide variety of protein components compared to the alkali-soluble fractions. The insoluble component was appeared as collagen map. Collagen from muscle and endothelial tissue were extracted which presented smilar bands, and 3 distinct bands(molecular weight above 110kDa) were consisted of β chain and two α chains, respectively. ATP-related compounds analysis showed that the ATP content in the humane slaughtered Takifugu rubripes skeletal muscle was high up to 4.32μmol/g, and the main degradation product IMP (1.35μmol/g) was obtained. And other further degradation products and content is almost zero. A total of 16 free amino acids were detected in the Takifugu rubeipes muscle. The content of lysine, arginine and threonine were higher, followed by glutamic acid, glycine and alanine, which had flavor function.

Abstract:Based on surface diffuse reflection visible spectrum, a universal method of non-destructive detection was presented for quantifying deoxymyoglobin, oxymyoglobin and metmyoglobin in fresh beef and pork. Spectral signals were collected by a spectral detection system, converted to reflectance absorbance, and combined with multiple linear regression to predict myoglobin in fresh beef and pork.And the prediction results were confirmed by using a visible spectrophotometer. The results showed that the surface diffuse reflection visible spectroscopy could be used for quantitatively detecting myoglobin, a significant linear relationship was existed between predicted results and experimental data, and R²≥0.9536. Therefore, non-destructive detection could quantify myoglobin in fresh beef and pork, and the presented non-destructive detection method might provide a promising quality supervising technology of fresh meat during producing and selling.

Abstract:In this study, Polygonatum sibiricum polysaccharides (PSPs) were extracted by deep eutectic solvents(DESs) with different ion combinations. The optimal effect of urea-choline chloride deep eutectic solvents was obtained. Based on single factor investigation, response surface analysis was used to investigate the optimum conditions for the extraction of PSPs by urea-choline chloride eutectic solvent. And the effect of DESs reuse on the extraction rate and content of PSPs was studied. The antioxidant activity of the PSPs in vitro was determined by measuring the total antioxidant capacity, O-₂ free radicals and DPPH free radical scavenging rate. The results showed that the optimum process parameters for PSPs extraction by DESs were as follows:temperature 70℃, urea-choline chloride molar ratio 1.19, extraction time 42.30min, liquid to material ratio 20.75mL/g. Under this condition, the extraction rate of PSPs was 18.55%, and the relative error was 2.69% compared with the predicted value, which was 139.97% higher than that extracted by the traditional hot water. The DESs reuse not only had no effect on the extraction rate of PSPs, and the maximum was 83.9% higher than that of fresh solvents when reusing for the third time; and the content of PSPs increased continuously and tended to be stable with increasing the repeated times. After 4 or 5 times of reuse, the PSPs content was basically stabilized at 63.48% and 64.12%, respectively, which indicated that the purity was increasing. The total antioxidant capacity, scavenging rate of O-₂ free radical and DPPH free radical was in dose dependent manner with mass concentration of PSPs, which was increased with the increase of mass concentration. The total internal antioxidant capacity was 241.2μg/mL, and the IC₅₀ of O-₂ free radicals and DPPH free radical scavenging capacity were 0.524mg/mL and 0.951mg/mL, respectively. Therefore, the DESs method was a new high-efficiency, clean and environment friendly method for extracting the Polygonatum sibiricum polysaccharides.

Abstract:Taking Hetian Junzao as raw material, response surface methodology (RSM) was used to optimize the extraction conditions of jujube polysaccharide. Three methods of removing protein of polysaccharide were compared to determine the final method for protein removal. The extraction rate of jujube polysaccharide was used for reference index, the effects of solid-liquid ratio, extraction time and extraction temperature on the extraction rate of jujube polysaccharide were studied. Based on single-factor experiment, RSM was used to optimize the combination of solid-liquid ratio, extraction time and extraction temperature. The results showed that the optimum extraction conditions were m (jujube)∶V (water)=1∶30(g/mL), extraction time for 3h, extraction temperature at 80℃. In this conditions, the extraction rate of jujube polysaccharide was 45.86%. Three methods including seveage method, trichloroacetic acid method and CaCl₂ method were used to study the deproteinization effect of jujube polysaccharide. The results showed that the trichloroacetic acid method had the best effect of protein removal and the lowest loss rate of polysaccharide. The removal rate of protein of trichloroacetic acid method was 82.08%, and the loss rate of polysaccharide was 15.21%.