Abstract:Big data technology refers to the ability to quickly obtain valuable information from various types of data. Big data technology is developing to make food science serve people better, which provides a new success insight and a scientific analysis strategy for food science, which can improve the performance of food science in food tracing, food matching, recipe recommendation, food safety, food producing management, food preference, and predictability and accuracy of food analysis in future. However, there are some challenges in big data application, such as data loss and difficulty to distinguish authenticity. This review introduced the application of big data in food industry, analyzed the challenges and the feasible solutions, and prospect tendency of food big data. Food scientists in the research area of food big data are encouraged to do further study based on our survey, contributing to food science from the perspective of big data and realizing the improvement of food science according to the future development trend of food.

Abstract:At present, hyperspectral imaging technology has made lots of achievements in meat safety quality prediction and classification. Research progress in meat toxic and hazardous substances detection, meat adulteration detection as well as meat sorting and grading was summarized, and the deficiency and development were discussed, in order to provide a reference for the research on nondestructive testing for meat safety evaluation.

Abstract:Phenols have been widely used in food systems because of their potential positive effects on human health. Furthermore, phenol-protein complexes can be formed in food systems through covalent or non-covalent interactions between phenols and proteins, affecting the structure and properties of proteins consequently. Therefore, the mechanism of phenolic-protein interactions, as well as the structural flexibility, functional properties, enzyme activity, oxidizability and digestibility of proteins were reviewed. Moreover, the common analytical methods to study the mechanism of phenolic-protein interactions were summarized. Finally, the future research direction of phenolic-protein interactions is also prospected.

Abstract:To evaluate the bactericidal activity in vitro and study the antibacterial mechanism of Atractylodes chinensis volatile oil. The antibacterial activity of Atractylodes chinensis volatile oil against Escherichia coli, Staphylococcus aureus and Candida albicans was evaluated by the suspension quantitative germicidal test. Its antibacterial mechanism was elucidated by measuring the effects on the leakage rate of extracellular alkaline phosphatase(AKP), soluble protein content and growth curve of the three strains. Volatile oil from Atractylodes chinensis could effectively inhibit or sterilize the tested microorganism. The contents of alkaline phosphatase(AKP) and soluble protein were significantly increased when compared with those in the control group, while the growth of indicators was suppressed significantly. The Atractylodes chinensis volatile oil showed prominent bactericidal activity by changing cell membrane permeability and destroying cell integrity.

Abstract:The CotA-laccase with good thermal stability and resistance to alkaline environments is known as a green catalyst and widely used in industrial dye degradation and wastewater treatment. The enzymatic properties of CotA-laccase cloned from Bacillus pumilus W3 expressed in E. coli was studied. Its yield was increased through optimizing fermentation medium. The recombinant expression of CotA laccase gene in E. coli was achieved by molecular means. The CotA-laccase fermentation medium was optimized by BP neural network and firefly algorithms, and the dye decolorization of recombined CotA-laccase was investigated. The recombinant CotA-laccase had good thermal stability and alkali tolerance. The optimal condition was pH 3.5 and 80 ℃.Recombinant CotA laccase showed goodaffinity for ABTS with a Km of 0.247 mmol/L and a Kcat of 41.32 s-1. The expression of recombinant CotA laccase was 1915.3 U/L under suitable conditions. The compositions of fermentation medium optimized by BP neural network and firefly algorithms were 1.16% of peptone, 0.428% of yeast powder, 1.06% of NaCl, 0.274 mol/L of CuSO ₄ and 0.931% of glycerol. The CotA-laccase activity of the optimized medium reached 3 088.68 U/L, which was 61.26% higher than that before optimization. The significant decolorization effect of recombinant CotA laccase on malachite green and acid blue 129 was observed, reaching 90%decolorization rate. CotA-laccase cloned from Bacillus pumilus W3 has good enzymatic properties, showing promising industrial application prospects.The BP neural network modeling combined with firefly algorithm is a feasible methodto optimize the E. coli fermentation.

Abstract:Using κ -carrageenase as the sole carbon source, 4 strains with κ -carrageenase activity were screened from 13 samples of sea mud with different coordinates in Dalian, Liaoning Province. The DNS method (3,5-dinitrosalicylic acid method) was then used to detect the κ -carrageenase activity produced by 4 strains. According to the κ -carrageenase activity comparison, a high-yielding strain was named LG-2, with a maximum enzyme activity of 34 U/mL. Based on morphological observation, physiological and biochemical identification, and 16S rDNA phylogenetic tree analysis, the strain was initially identified as Rhodococcus and Gram-positive bacteria. The growth curve and enzyme activity curve of LG-2 strain were determined, laying the foundation for industrial production.

Abstract:Soaking and steaming are important operations in the processing of rice products such as Chinese rice wine. Soaking is not only time-consuming but also affects the steaming process of rice, resulting in half-cooked or over-cooked rice, which affects the subsequent saccharification and fermentation. In order to increase the water absorption rate of rice and improve the gelatinization of steamed rice, the rice was soaked by simultaneous vacuum and ultrasonic treatment, vacuum followed by ultrasonic treatment, and ultrasonic followed by vacuum treatment, respectively. Their effects on water absorption and steaming characteristics of rice were discussed. It was found that vacuum followed by ultrasonic treatment could accelerate the penetration and diffusion of water, reduce the hardness of rice, significantly shorten the steaming time and inhibit the retrogradation of steamed rice. This study provides the possibility of the application of vacuum followed by ultrasonic treatment in the production of Chinese rice wine.

Abstract:D-psicose can be produced from D-fructose using D-psicose-3-epimerase (DPE). However, the reaction catalyzed by DPE is reversible, which eventually reaches equilibrium between the D-fructose and D-psicose leading to a low conversion rate. L-rhamnulose kinase (RhaB) catalyzes the phosphorylation of ketoses in an irreversible way. In a cascade reaction based on the combination with DPE, RhaB can break the equilibrium by phosphorylating the D-psicose. Thus, an increased production of D-psicose can be expected. Polyphosphate kinase(PPK) is overexpressed in the cascade reaction to establish the ATP-regeneration system in order to reduce the industrial costs. DPE, RhaB and PPK were overexpressed in E. coli Rosetta(DE3) respectively to explore the optimum condition and the product yield. RhaB protein with a molecular weight of 5.3×104 was thus achievedat pH 8.0 under 35 ℃. When RhaB coupled with DPE, the consequent yield of D- psicose could reach 70% under optimum condition, i.e.,pH 8.5, 35 ℃, Mg2+ and DPE∶RhaB of 1∶2. In the cascade reaction of DPE and RhaB combined with PPK, the ATP concentration was reduced to 1/5 of D-fructose and the yield of D-psicose was 50%. The results provide a theoretical basis for the industrial production of D-psicose.

Abstract:The effect of antibacterial paper on toast preservation was studied. A paper-plastic composite material obtained via the combination of antibacterial paper and PP film was used to package the toast to investigate its difference of the texture, color difference, water activity, total number of colonies and enthalpy value comparing with the toast packed only in PP film or unpacked. The toast packed in paper-plastic composite material showed slower deterioration of texture and color difference, reduction of water activity, effective suppression of total colony number increase and suspension of enthalpy raise. This paper-plastic composite material can avoid direct addition of preservatives to food, effectively prolonging the shelf life of toast.

Abstract:The effect of different ultrasound time on the hardness of tomato and loofah was investigated. The hardness and sensory of tomato and loofah during storage were studied by cross-matching different gas compositions, i.e., O ₂2 with concentration of 3%, 6% and CO ₂2 with concentration of 2%, 4%, 6%. After the optimization of ultrasound time and gas composition of modified atmosphere packaging(MAP), the preservation of tomato and loofah mixed storage was evaluated via cold storage, MAP, ultrasound treatment (UT) and ultrasound treatment combined with modified atmosphere packaging(UTMAP). The results showed that 5 min of ultrasound time was most effective in maintaining the hardness of tomatoes and melons. The highest hardness and sensory score were achieved when stored under 6% O ₂, 4% CO ₂ and 90% N2 for 21 d. The increase of weight loss, the accumulation of malondialdehyde(MDA) and the change of respiration in tomato and loofah mixed storage under UTMAP were slower than those stored under other treatments, exhibiting similar taste with fresh tomato while the flavor of loofah was significantly different from that of cold storage. The UTMAP is therefor much effective than UT alone or MAP alone for tomato and loofah mixed storage.

Abstract:In order to improve the production efficiency of black garlic and accumulate more functional components, the effects of the initial water activity (A _w ), temperature, and incubation time on the contents of 12 Amadori compounds (ACs), S-allyl cysteine (SAC), alliin in black garlic were studied by a single-factor optimization test. The differences between this prepared black garlic and commercially available ones in the above-mentioned functional components, 5-hydroxymethylfurfural(5-HMF), acrylamide, antioxidant activity and sensory quality were compared. The optimal conditions were as follows: initial aw was 0.87, processing temperature was 70 ℃ and the processing time was 14 days. Compared with the commercial products, the total functional components content (10 337.01 μg/g) in black garlic prepared under these conditions was significantly higher, meanwhile, their concentrations of 5-HMF and acrylamide were lower. This black garlic also showed the highest antioxidant activity in the ferric reducing antioxidant power (FRAP) and DPPH assays. Its sensory quality was similar with the commercial products. The optimized process significantly reduced the processing time of black garlic by 88%, effectively increased the content of functional components and decreased the content of harmful substances in the subsequent Maillard reaction.

Abstract:Identification of E. coli strain by MALDI-TOF MS was improved by synthesis of Fe ₃O ₄-COOH nanomaterials. The fingerprint peaks of E. coli strain, as well as the resolution and sensitivity of MALDI-TOF MS detection were increased by the enrichment of bacterial proteins in E. coli K-12 and DSM 30083T lysate. Results showed that E. coli K-12 had four matching peaks, while E. coli DSM 30083T had eight peaks, which thus improved the identification of E. coli strains by MALDI-TOF MS.

Abstract:The garlic aqueous extracts which can prolong the shelf life of sauced chicken claws was investigated via K-B in vitro bacteriostasis test based on E. coli and S. aureus. The extracts obtained by common aqueous extraction method was selected as the best preservative according to the results of bacteriostasis experiment and sensory evaluation. The immersion method was then used to preserve the sauced chicken claws. The actual fresh-keeping effect during storage was determined by measuring the total viable counts and the volatile flavor components (gas chromatography-mass sepetrometry, GC-MS). The results showed that the garlic aqueous extracts had strong bacteriostasis, exhibiting good preservation effect on the volatile flavor of sauced chicken claws. Garlic aqueous extracts are natural bacteriostatic substances which can be used in cooked sauced chicken claws preservation. More important, this method provides a new idea for the preservation of cooked meat products.

Abstract:This study was to investigate whether the combination of aqueous extracts from maca (Lepidium meyenii Walp)，Polygonatum sibiricum and Platycodon grandiflorum could effectively regulate glucose and lipid metabolism at cellular level. Ultrasonic-assisted water extraction was adopted to obtain their aqueous extracts. The HJJG aqueous extract was achieved by mixing the extracts form Polygonatum sibiricum (HJ) and Platycodon grandiflorum (JG) at a mass ratio of 1∶1. A glucose-lipid metabolic disorder model was established by inducing human hepatocellular carcinoma cell line (HepG2) with free fatty acid，fructose and glucose. Metformin was used as the positive control group to evaluate effects of aqueous extract of maca，HJJG or maca-JHHG mixture on the model cells at different concentration (0.25，0.5, 1 mg/mL). The glucose absorption，intracellular glycogen，triglyceride (TG)，total cholesterol (TC) and reactive oxygen radicals (ROS) levels in the model cells were measured. The results showed that glucose and lipid metabolism in model HepG2 cells could be significantly regulated by combing maca and HJJG aqueous extracts. They coordinately promoted the sugar absorption and intracellular glycogen synthesis. They also reduced the levels of TC and intracellular ROS in cells (P < 0.05)，especially. The mixture of maca (1 mg/mL) and HJJG (1 mg/mL) at a volume ratio of 1∶1 exhibited the best effect.

Abstract:The effects of deep-frying edible oil (DFEO) on liver injury in rats and its mechanism were studied using oralgavage of DFEO with given doses. After 6 weeks of intervention, liver index in the DFEO group decreased significantly(P<0.05), while the serum levels of aspartate transaminase(ALT) and aspartate aminotrans ferase(AST) significantly increased (P<0.01).Meanwhile, observation of tissue sections of liver showed that a large number of fat vacuoles and liver sinusoidal expansion in the DFEO group. However, liver cell boundaries were not clear and inflammatory cell infiltration appearedin local glands. The quantitative real-time PCR results showed that 6 weeks continuous consumption of DFEO would cause significant down-regulation of Gsta2、Gsta3、Gclc、Gclm in rat liver tissues(P<0.01). DFEO will cause serious damage to the liver tissue and destroyliver cell morphology, and its long-term intake will damage the normal gene expression leading tonormal life activities affection.