Abstract:Future food has gained extensive attention from the public and food researchers with the pursuit of health, environmental protection and delicious food. With the rapid development of biological science and food technology, more and more foods will be biosynthesized in the future, which will become the guide and drive for the development of high-tech food in a long period. At present, advanced synthetic biology and food science and technology have made a series of breakthroughs in the customized food production such as artificial meat, becoming an effective supplement and alternative to the existing traditional agriculture and food industry. In this review, we analyze the key tasks and major challenges for the biomanufacture of typical future foods such as food-plant based meat and cell-cultured meat, and introduce the application of synthetic biology, tissue engineering, fermentation engineering in the future food industry. Furthermore, we also summarize the potential challenges in future food industry such as the multidisciplinary integration of food in biological manufacturing.

Abstract:The new round of scientific and technological revolution has accelerated the reconstruction of the global food innovation landscape and reshaped the global food industry structure. Future food fundamental science is the guideline of the development of high-tech food in the future, and the promotion of a 'post-animal bioeconomy', which will drive the leapfrog development in the post-industrial era. This article analyzed fundamental science issues such as food omics, food perception, food synthetic biology and food nanoscience, discussed the opportunities and challenges of future food, and looked forward to future food development trends and prospects.

Abstract:The allergy peptides from food protein digested by gastrointestinal tract were presented by dendritic cell to T cells, which led to allergic reaction. T cells could differentiate into certain subgroups and play different roles in immune reaction. Among them, the down-regulation of Th1/Th2 was considered as a trigger of the hypersensitivity reaction such as food allergy. The role of Th9, Th17, Tfh and other Th cells cannot be ignored in the development of allergic reactions. Therefore, this review comprehensively summarized the research of T cells on food allergy, introducing the roles of T lymphocytes with different subgroup, prediction and mapping of T cell epitopes in common allergen proteins, and the application of T cell epitopes, etc.

Abstract:Oxidative stress is one of the major causes of ulcerative colitis(UC), and superoxide dismutase(SOD) is the basic molecule to regulate oxidative stress. This study investigated the therapeutic effect of oral administered TAT-SOD liposome (L-TAT-SOD) on UC rat models.The isolated and purified TAT-SOD from the fermentation broth of recombinant Pichia pastoris was achieved by ethanol precipitation, macroporous resin column chromatography and TritonX-114 phase separation. Subsequently, the L-TAT-SOD was prepared by reverse evaporation. Finally, the UC rat models were established by dextran sodium sulfate (DSS) induction and administered by intragastric administration. The anti-UC effect of L-TAT-SOD was evaluated by DAI score, colon density, damage of colon tissue, serum SOD enzyme activity and serum lipopoly saccharide content.Results showed that: The specific activity of isolated TAT-SOD was 11 003 U/mg. The recovery rates of enzyme activity of successfully prepared L-TAT-SOD were about 80% and 90% in simulated gastric and intestinal juice, respectively. In anti-UC experiments, all administered groups had lower DAI scores(P<0.05) than that of the model group. In contrast, the L-TAT-SOD group had the lowest DAI score.The results of colon density and tissue section showed that the damaged colon tissue was significantly repaired in all administered groups, and the L-TAT-SOD group performed best.Meanwhile, the serum SOD enzyme activity was significantly increased in all groups(P<0.05), and the activity in L-TAT-SOD group was highest. However, there was no significant difference in serum lipopolysaccharide content in each group. The oral administered L-TAT-SOD is confirmed with a beneficial therapeutic effect on DSS-induced UC rat models, expected to be a new option for the adjuvant therapy of UC.

Abstract:Bitter apricot kernel contains various bioactive components and nutrients and can be used as value-added food ingredients. However, it is also an allergen which may cause risk to allergic people if they consume foods containing bitter apricot kernel.To investigate the impact of ultra-high pressure on the structure and immunoreactivity of bitter apricot kernel protein isolate, the spatial structure and allergenicity under different pressures were detected by circular dichroism, fluorescence spectroscopy and enzyme linked immunosorbent assay(ELISA). The results demonstrated that ultrahigh pressure treatment at 100~500 MPa for 900 s insignificantly changed the secondary structure of bitter apricot kernel protein isolate. However, with the increase of pressure intensity and processing time, the tertiary structure of bitter apricot kernel protein isolate was unfolded and the hydrophobic groups were thus exposed, which led to the increase of fluorescence intensity and surface hydrophobicity and the decrease of immunoreactivity. The reduced immuno- reactivity of bitter apricot kernel protein isolate was possibly due to the changes of conformational epitopes causing food allergy. This study may provide important implications for the development of safe bitter apricot kernel food and beverage products.

Abstract:In order to improve the resource utilization of mung bean protein, the waste produced in the mung bean starch production, the optimal conditions for preparing mung bean antioxidant peptides by enzymatic method were studied, and their antioxidant activity was also investigated. The enzymatic hydrolysis of mung bean protein was optimized by different proteases or their complex enzymes, with other factors examined including the reaction time and the enzyme amount. The antioxidant capacity of the hydrolyzed polypeptide was tested by in vitro antioxidant experiment. The optimal reaction conditions were finally established as follows: 2% of neutral protease and 3% of substrate were used for 3 h hydrolysis at pH 7 and 50 ℃. The resulted mung bean peptide solution had a DPPH free radical scavenging rate of （91.58±2.44）% with a mass concentration of 5 mg/mL, showing strong reducing ability. Five separated fractions were obtained by purification using gel chromatography column. The small molecule peptide component 5 had the strongest antioxidant capacity, which was higher than other large molecule peptides and unseparated peptides.

Abstract:The antioxidant and bacteriostatic activities of five coating agents, including 1% chitosan (Chi), 1% Cordyceps militaris water extract(CM), 1% Cordyceps militaris waste extract (SS), 1% chitosan combined with Cordyceps militaris water extract(Chi+CM) and 1% chitosan with Cordyceps militaris waste extract(Chi+SS), were investigated to study the preservation effects of chitosan coating and water extracts of Cordyceps militaris and its leftovers on the fresh fruits and vegetables. Chi+CM coating agent showed the best DPPH free radical scavenging ability, which also revealed the strongest antibacteria activity in the inhibition zone test. The inhibition of chitosan to Gram-positive bacteria could be enhanced by Cordyceps militaris water extract. When applied to zucchini stored at 6 ℃, the water extract of Cordyceps militaris combined with chitosan coating was found to reduce the weight loss, browning and hardness decline of zucchini, to maintain the soluble solids and ascorbic acid content, and to reduce the accumulation of MDA, POD and POD activity caused by oxidative stress and oxidative damage. In addition, it could inhibit microbial reproduction during storage.

Abstract:Monascus yellow pigment oleoresin was applied in different food systems (liquid, semi-solid and solid) by either direct addition or encapsulated in powder. The color changes of Monascus yellow pigment oleoresinin various foods were investigated by spectrophotometer and the color stability was thus analyzed. Furthermore, the causes and mechanism of discoloration were discussed. The pigment could maintain bright yellow color in soft drink. When it was added into butter cookie and custard, a red tone was observed. The microcapsulated pigment effectively protected the color tone in custard. The unknown components in Monascus yellow pigment besides the Monascin pigments could react with unionized amino groups in food, which consequently produce red pigment and subsequently turn the color tone to red.

Abstract:Pseudomonas putida is one of the most important industrial microorganisms, widely applied in environmental remediation, production of bioactive natural products and secondary metabolites, etc. To enhance the n-butanol tolerance of Pseudomonas putida 901, atmospheric and room temperature plasma(ARTP) was performed to generate mutant library. After gradient adaptation in n-butanol, a mutant capable of tolerating 12 g/L n-butanol was obtained. The whole genome was re-sequenced and analyzed through Illumina HiSeq platform. About 19 million reads was obtained with an average read of 150 nt. Compared with the reference genome, the fragment pairing rate was 92.03%,while the coverage rate was 90.34%. A total of 40 704 single nucleotide variations was detected, with isozygoty of 39 319 and heterozygote of 40 704. There were 2 153 inserts and deletions, with homozygous mutation sites of 1 871 and heterozygous mutation sites of 282. All the mutations were functionally annotated according to GO/KEGG database.

Abstract:To study the effects of β-glucan(HBBG) and arabinoxylan(HBAX) extracted from highland barley on the gelatinization and rheological properties of corn starch(CS), highland barley-derived polysaccharides with a series of concentrations were mixed into CS solution. The viscosity properties and morphological features of different mixtures were studied by rapid-visco analyzer (RVA), rheometer and scanning electron microscope (SEM). The results indicated that both HBBG and HBAX reduced the breakdown value, increased the gelatinization peak time, and finally improved the thermal stability of CS gel. HBBG with linear chain structure increased the apparent viscosity, storage modulus (G′), and loss modulus (G″), thus enhancing the viscoelasticity of CS gel by cross-linking with starch and self-aggregation. However, HBAX with highly branched structure reduced the amount of leached amylose, peak viscosity, consistency coefficient (K), G′ and G″, consequently increasing the fluidity of CS system by covering around the starch granules to inhibit the swelling of starch.

Abstract:The soybean isoflavone was firstly extract from soy sauce residue by ethanol extraction method, and the extraction conditions were optimized. The crude isoflavone extract was further purified by 6 methods including alcohol precipitation, isoelectric precipitation, concentrated centrifugation, n-butanol, dichloromethane, and ethyl acetate extraction. Finally, the composition of isoflavone monomer after purification was identified by high performance liquid phase, and its in vitro antioxidation was evaluated by the pyrogallol oxidation and DPPH methods. The optimized extraction of crude isoflavone yielded the isoflavone content of 1.21% and the extraction rate of (85.36±0.09)%. Among the 6 purification methods, the isoflavone content obtained by the concentrated centrifugation method was 7.75% with best removal of protein. The isoflavone content obtained by the dichloromethane extraction method was 27.74% with best removal of total sugar and ash. The purity of the isoflavone was 44.88% when the two methods combined, and it was composed by genistein, glycintein and daidzein, accounting for 67.37% and 9.33%, 23.30%, respectively. The scavenging rates of purified isoflavones(1 mg/mL) to superoxide and DPPH free radicals were 67.65% and 89.18%, which were significantly higher than isoflavones crude extracts(P<0.05). And their IC₅₀ were 0.34 and 0.26 mg/mL. The isoflavone purified products achieve certain antioxidant activity, expected to be used as potential natural antioxidants in functional foods.

Abstract:Headspace sampling combined with gas chromatography-mass spectrometry (GC-MS) was used to determine the aroma components of six aroma types of white teas including grassy aroma, floral aroma, pekoe aroma, reed leaf aroma, jujube aroma and medicinal aroma. Their differences were analyzed by cluster analysis and principal component analysis. There were totally 48 kinds of aroma substances identified in six aroma types. The main characteristic components of grassy aroma were linalool, 1-penten-3-ol, hexanal, (Z)-3-hexen-1-ol and 2-methyl-1-butanol. The floral aroma was composed of linalool, 1-penten-3-ol, hexanal, 2-methyl-1-butanol and geraniol. Linalool, 1-penten-3-ol, 2-methyl-1-butanol, hexanal and geraniol were the main components of pekoe aroma. The reed leaf aroma components were mainly characterized by 1-penten-3-ol, 2-methyl-1-butanol, hexanal, linalool and 2-ethylfuran. And the main characteristic components of jujube aroma were 1-penten-3-ol, 2-methyl-1-butanol, hexanal, linalool and (Z)-3-hexen-1-ol. The main components of medicine aroma were 1-penten-3-ol, 2-methyl-1-butanol, linalool, hexanal and 2-ethylfuran. Six types of white tea aroma were divided into two categories by cluster analysis. Grassy aroma, floral aroma and pekoe aroma were clustered in one category, while reed leaf aroma, jujube aroma and medicinal aroma belong to another. Among all the aroma components, 1-penten-3-ol and linalool are important aroma compenents for distinguishing the different aroma types of white tea.

Abstract:Freezing is a common method of pork storage. However, long-term frozen storage greatly impacts the quality of raw and cooked pork. The effects of freezing time (0, 120, 240, 360 d) on the nutritional quality, edible quality and storage characteristics of pork before and after heating at -18 ℃ were investigated. With the prolongation of frozen storage time, the water content, elasticity and soluble protein content of raw and cooked pork decreased significantly (P<0.05), while the free amino acid content, POV value and TBARS value all increased significantly (P<0.05). The hardness, adhesive property and chewiness gradually increased. The results of electronic nose showed a significant difference in flavor among groups (P<0.05). The quality of pork decreased significantly with the extension of freezing storage time, and the quality severely deteriorated with the edible value decreased after 120 days of frozen storage.

Abstract:Salmonella typhimurium (S. typhimurium) can cause salmonellosis and is highly drug- resistant, causing seriously hazards on the health of both human and animals. The metabolites of S. typhimurium inoculated on NB medium, dried bean curd and dried beef medium were detected by Gas Chromatography-Mass Spectrometer(GC-MS). Principal component analysis (PCA) and orthogonal partial least squares discrimination analysis(OPLS-DA) were used to identify the characteristic and differential metabolites. The probably metabolic pathways of the characteristic and differential metabolites were analyzed based on the gene annotation of S. typhimurium. Significant growth of S. typhimurium was observed after inoculated dried bean curd and dried beef. The characteristic and differential metabolites were alkanes, phenols, small molecular acids, small molecular alcohols, etc. Gene annotation of S. typhimurium showed a large number of carbohydrate metabolism genes, involved in the production of 1-butanol. Therefore,1-butanol is a typical metabolite of S. typhimurium polluted dried bean curd and beef jerky.