Abstract:Food safety risk assessment is the basis for the food safety risk management and an important system for the establishment of the “Food Safety Law”. The National Health Administrative Departments established the risk assessment mechanism and reinforced the construction of the risk assessment system. About 30 priority and emergency risk assessment projects were carried out to provide support for the establishment of food safety standards, supervision of food safety, and response for the food safety emergency. Meanwhile, the basic research of risk assessment was reinforced and the effective implementation of the risk assessment system of “Food Safety Law” was guaranteed.

Abstract:This study will provide references for research and development and selection of clinical enteral nutrition formula foods for special medical purposes based on the statistical analysis of carbohydrates, fats, proteins, minerals, vitamins, and dietary fiber, osmotic pressure and C/N ratio. According to the recipe abroad for special medical purposes food manufacturer's web site data, the histogram and statistical methods were used to analyze the compositions and clinical application of foreign foods for special medical purposes. Depending on the administration objects, the contents of protein, lipid, carbohydrate, vitamin, and mineral, heat supply ratio of carbon and nitrogen, osmotic pressure, and energy density were different for different types of foods. The formula foods for special medical purposes should be adjusted based on the nutritional contents, osmotic pressure, and energy density.

Abstract:According to the current situation of the development of foods for special medical purposes to diabetes and the characteristics of the metabolism and nutrition demand for diabetic patients, this article discusses the main study points on foods for special medical purposes to diabetes patients, including the formula, form, processing procedure, quality standard and stability of the products.

Abstract:In order to investigate effects of 6-gingerol on gel properties and storage stability of surimi, different concentrations of 6-gingerol were added into grass carp surimi in this study. The changes of gel strength, water holding capacity (WHC), color, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), total sulfhydryl content, and total bacterial count of the surimi gel during refrigerated storage at 4℃ were analyzed. The results indicated that the addition of 6-gingerol significantly increased the gel strength and WHC of surimi gel, which increased firstly and then decreased with the increase of 6-gingerol amount, and reached the maximum when the dosage was 1%. Meanwhile, 6-gingerol could delay the decline of gel strength, WHC, whiteness and total sulfhydryl content, and inhibit the increase of TVB-N, TBARS, and total bacterial count. Therefore, in the production of surimi products, addition of 6-gingerol (1%) could improve surimi gel properties and extend its shelf life.

Abstract:In order to explore the mechanism on nano fish bone (NFB) improving gel strength of fish protein, effects of CaCl₂, NFB, nano hydroxyapatite (HAP) and nano hydroxyapatite and collagen (HAP and CLG) on the gelation properties of silver carp actomyosin were comparatively investigated in this study. Calcium ion concentration was the same between the CaCl₂ and NFB groups. And the particle sizes of the NFB and HAP were the same. Breaking force of the NFB actomyosin gel was the same as that of the CaCl₂ group (p>0.05), and significantly higher than that of HAP and HAP and CLG groups. Hydrophobicity, total sulfydryl group sulfydry group, and microstructure were not significantly different among the five group of actomyosin gels (p>0.05). The SDS-PAGE gel results showed that gel of myosin heave chain dimer (MHC₂) was not visible and the gels of HAP and HAP and CLG groups had a higher intensity. Meanwhile, the CaCl₂ and NFB groups had the higher intensity gels. The results indicated that NFB increased the gel strength of actomyosin gel by the means of activating endogenous TGase, which catalyzed the formation of MHC₂.

Abstract:Aminopeptidase is a kind of exopeptidases that specifically cleaves amino acids from the N-terminal of proteins, and thus has wild applications in food industry. In this study, an aminopeptidase was isolated to homogeneity from oysters (Alectryonella plicatula) by ammonium sulfate fractionation and a series of chromatographic steps including DEAE-sepharose, phenyl-sepharose and hydroxyapatite. The aminopeptidase was strongly suppressed by bestatin, a specific aminopeptidase inhibitor. The 2D-PAGE results showed that molecular weight and pI value was approximately 100 ku and 5.8. By MALDI-TOF/TOF mass spectrometry analysis, 12 peptide fragments with 138 amino acid residues in total were obtained and these peptide fragments were identical to a puromycin-sensitive aminopeptidase from Crassostrea gigas, which confirmed that the purified enzyme was an aminopeptidase B. Circular dichroism spectroscopy analysis indicated that the secondary structure of aminopeptidase B (APB) was mainly random coil (42.6%) and reverse parallel (32.0%). The K_m and k_cat was 1.5μmol/L and 117.5s-1 and the k_cat/K_m was 78.3L/(μmol·s)-1. The optimum temperature and pH of APB was 35℃ and 7.0. Under these conditions, APB could hydrolyze Lys-MCA and Arg-MCA to release Lys and Arg, which had the oyster’s flavor.

Abstract:Auxistapeionosoma Bleeker is a kind of tuna in the South China Sea with high yield and low value. This study analyzed the proximate composition, amino acid composition of the ordinary meat and dark meat hydrolysates, and evaluated their anti-fatigue activity by animal experiment. The total amino acids of the ordinary muscle hydrolysate powder (OMHP) and dark muscle hydrolysate powder (DMHP) of Auxistapeionosoma Bleeker were 57.06% and 58.90%, respectively. The branched chain amino acids accounted for about 18% of the total amino acids. The contents of the components in OMHP and DMHP with molecular weight below 5000Da were both up to 70%, and the content of below 700Da was both more than 20%.Compared with the control group, the OMHP and DMHP could significantly prolong the swimming time of mice (p<0.05), increase liver glycogen reserves of mice (p<0.05), and lower the serum urea nitrogen in mice after exercise (p<0.05). It showed that both had anti-fatigue activity, and there was no significant differences between them. The results showed that the OMHP and DMHP of Auxistapeionosoma Bleeker from South China Sea could be used as potential anti-fatigue health care products.

Abstract:The fermentation conditions of chicken blood hemoglobin (Hb) for the preparation of small peptides by Aspergillus oryzae were optimized and the molecular weight distribution of the polypeptides were determined. On the basis of single factor experiments, response surface analysis methodology (RSM) were used to optimize the preparation conditions about Hb polypeptide. A regression model for Hb polypeptide yield was established to optimize the fermentation process and the distribution of Hb polypeptide molecular weights were determined by the gel chromatography method. The results showed that factors affected the Hb polypeptide yield were inoculation amount, culture temperature, initial pH, and the fluid volume. The optimal conditions were inoculation amount 7.9%, culture temperature 30.2℃, initial pH 7.01, and medium volume 61mL. Under these conditions, Hb polypeptide yield increased from 1.85mg/mL to 2.18mg/mL. According to the gel chromatography method, the Hb peptide molecular weights were mainly concentrated in the range of 1000-6500u, of which 1600-2500u took up the most abundant (38.39%).

Abstract:Melanin is produced by plants or micro-organisms, and has broad application prospects in the food, cosmetics and medicine. Bacteria S_8nyzx-1 that can produce melanin was isolated from black garlic of 96h fermented. The strain was identified according to colony morphology and molecular biology. The structure characteristic of this melanin was identified using the techniques of UV and IR spectroscopy,and high temperature ability for a short time was determined. The results showed the colony was neat edges, white opaque, dry surface, wrinkled, and surrounded by a small amount of brown pigment on LB. 16S rDNA fragment (1419 bp of size) was 99.8% of similarity with Bacillus subtilis. The strain had a high ability of survive 10min at 93℃ water bath. The melanin had strong absorption peak at 370-390nm through UV and with the indole structure through IR, which was considered for eumelanin according the characteristics of the bacteria can use L-tyrosine.

Abstract:In order to study bio-molecules damage protective effect and free radical scavenging capacity of Coriandrum sativum L. (coriander), Folin-phenol assay was used for estimating total polyphenol of coriander. Gel electrophoresis was performed for detecting DNA and protein damage protective effect of coriander. Free radical scavenging capacity of coriander extract was evaluated using DPPH assay. ORAC assay was used to confirm the value of oxygen radical absorbance capacity. The result showed that the content of total polyphenol was 4.054μg/mg and the minimum protective concentrations on DNA and bull serum albumin were 4.0μg/mL and 125.00μg/mL. The IC₅₀ value for DPPH radical scavenging ability was 0.17μg/μL while the ORAC value for antioxidant capacity was 485.3. The result indicated that the coriander extract had distinct antioxidant activity.

Abstract:The present research evaluated the effects of tea polyphenol and rosemary extract combined with nisin on the quality of weever (Lateolabrax japonicus) during refrigerated storage at 4℃. The sample was firstly dipped into a solution of tea polyphenol (2mg/mL), rosemary extract (2mg/mL), and nisin (3mg/mL) for pretreatment and then drained off to storage at 4℃. The fish physicochemical (pH, PV, K value, TBA value, TVB-N value, and total mercaptans), microbiological (total viable count), and sensory attributes were selected as the evaluation index and periodically assessed over 20 days. The results indicated that the experiment groups treated with tea polyphenol and rosemary extract combined with nisin could effectively raise the total mercaptans content and lower the pH, PV, K value, TBA value, TVB-N value, total viable count and sensory attributes compared with the blank groups. Moreover, the total sulfydryl content was significantly higher than the blank group. The treatment finally extended the shelf life of weever by 4-6 days during the refrigerated storage.

Abstract:This study investigated effects of konjac glucomannan (KGM) and whey protein (WP) compound coating on preservation of Guanxi honey pummelo. Guanxi honey pummelo coated with KGM and WP was stored at room temperature while Guanxi honey pummelo without coating was as the control. During the storage, the weight loss rate, total sugar content, respiration, ethanol content, relative permeabi-lity of plasma membrane, malondialdehyde (MDA) content, and peroxidase(POD) activity of Guanxi honey pummelo were determined to evaluate effects of the coating. Results showed that composite edible coating exhibited a beneficial effect on the overall quality of Guanxi honey pummelo at room temperature by reducing fruit weight loss, protecting the cell wall and reducing respiratory intensity,inhibiting physiological metabolism,decreasing the nutrient loss, and delaying the graining. All indexes by KGM and WP coating were significantly better than the control group after 120 days storage at room temperature.

Abstract:In order to improve the utilization and the development of Pleurotus eryngii snack foods, impacts of pre-treatment process on the qualities of vacuum fried mushroom were investigated. Effects of slice modes, slice thickness, and blanched treatment were studied. The results showed that slice modes had significant effects and crisp crispness and oil content were positively correlated with slice thickness. Meanwhile, 2mm was the optimum thickness and L values were negatively correlated with the slice thickness. The blanching destroyed the polyphenol oxidase and peroxidase activities in mushroom crisps, which inhibited browning and the best treatment conditions were 95℃ and 90s.

Abstract:Using black teas at home and abroad as materials, inductively coupled plasma mass spectro-meter (ICP-MS) method was adopted to determine the content of (Cu), lead (Pb), arsenic (As), mercury (Hg), chromium (Cr), cadmium (Cd) and 16 rare-earth elements (counted by total amount of oxides ∑ReOs). And on this base we evaluated the safety of the heavy metal according to national and industrial standards including “Green Food Tea, Organic Tea and Maximum Levels of Contaminants in Foods”. The result showed that content of Pb in all samples was lower than 5μg/g which met the limitation of national standard about Pb in teas. According to organic tea, one sample did not meet this standard about Pb content and three samples did not meet this standard about Cu content. According to green food tea, three samples did not meet this standard about heavy metal content. According to NY 659—2003 “Residue Limits for Chromium, Cadmium, Mercury, Arsenic and Fluoride in tea”, Cr content in two samples was beyond this standard. Result of rare-earth metal showed that ∑ReOs in 10 samples were out of range of 2mg/kg. On the whole, the pass rate of tea samples about heavy metal was 72.97%.