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关键词： Chitosan  

摘要： Nanoparticles were prepared with encapsulation of nisin in chitosan (NCNs) using two different preparation treatments. The nanoparticles were characterized through Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and particle size examinations. The nanoparticles from treatment with optimum size (1003.6 +/- 13.6 nm) were added to the sausage and stored at 4 degrees C for 20 days. The changes in total viable counts (TVC), color, thiobarbituric acid reactive substances (TBARS), pH, texture analysis (TCA), and total volatile basic nitrogen (TVB-N) in encapsulated nisin in chitosan nanoparticles, chitosan, and nisin separate treatments was calculated and compared to the control group with no additives (p < .05). Results claimed that 0.6% chitosan plus 0.1% nisin treatment offered better quality preservation impacts including TVC growth control, TVB-N, and TBA reduction (p < .05), as well as pH and color maintenance compared to the control, chitosan, and nisin separate treatments (p < .05). Novelty impact statement Nisin-loaded Chitosan can act as a commercial additive to extend the shelf life of fish sausage. Nisin/chitosan nanoparticles show considerable biochemical effects on the preservation of lipids and proteins. Chitosan can be a powerful wall of capsules releasing nisin under control to the food matrix.

关键词： Human health   Magnetism   Mineral nutrition   Organic fertilization   Ozonated water   Soil leaching   Superabsorbent polymers   Zeolite  

摘要： Medicinal plants are important sources of biochemical compounds affecting human health. However, because large areas of the world are subjected to different stresses including salinity, it is important to find methods, which may control the growth and biochemical properties of medicinal plants in such conditions. Another aspect of cropping medicinal plants in saline soils is the alteration of their biochemical properties by stress. Due to the significance of planting medicinal plants in saline soils, the objective of the present review article is to investigate and analyze the physicochemical approaches including soil leaching, organic fertilization, mineral nutrition, ozonated water, magnetism, superabsorbent polymers, and zeolite, which may control the effects of salinity stress on the growth and biochemical properties (production of secondary metabolites) of medicinal plants. In our just-published review article, we investigated the biological approaches, which may affect the growth and biochemical properties of medicinal properties in saline soils. Although salinity stress may induce the production of biochemical products in medicinal plants, the use of physicochemical approaches is also recommendable for the improved growth and biochemical properties of medicinal plants in saline soils. More has yet to be indicated on the use of the physicochemical approaches, which may affect the growth and biochemical properties of medicinal plants in salt stress conditions.

关键词： Aged rice   Rice starch   Multi-scale structure   Pasting properties   Digestibility  

摘要： Rice short-term (less than 12 months) storage significantly affected starch structures and physicochemical properties, and in turn, influenced rice functionalities. However, effects of rice long-term (more than 12 months) storage on starch structures and functionalities have been not resolved yet. This study revealed the changes in structures and physicochemical properties of starch during rice long-term storage (12-36 months). Rice storage resulted in degradation of starch molecules, which increased amylose content and reduced the content of long branch-chains of amylopectin, double helices, short-range ordered structures, crystalline structures, and lamellar ordering degree along with apparent erosion of starch granules. Those structural changes significantly increased starch thermostability, favored starch short-term reassociation, and promoted starch enzymatic digestion. Comparing with the short-term storage (1 year of storage), the long-term storage (2 or 3 years of storage) yielded a more serious degradation on starch multi-scale structures, and in turn, resulted in a higher thermostability, and better-defined gel structures and higher starch digestion extent after cooking and cooling. Compared with the short-term aged rice, the long-term aged rice is a better candidate to prepare rice-based gel-like foods such as noodles. This study provided a promising pathway to control structures and physicochemical properties of rice starch and even rice-based foods via simply controlling rice-storage time.

关键词： Sugar (sucrose)  

摘要： This study was aimed at investigating the impact of different non-caloric and reduced-calorie sugar blends on the physicochemical, rheological and sensory properties of sweet confectioneries. The systems were formulated using low-methoxyl pectin (1% wt/vol) and orange juice processed by pilot-scale UV-C light (Dean-Vortex reactor;390 mJ/cm(2);Reynolds number: 3824). Consumer perception was measured using the conjoint, difference from control and CATA tests. A control, elaborated with sucrose (S:10% wt/vol), and 27 systems containing blends of S (0-6.0% wt/vol), erythritol (E:0-11.0% wt/vol), rebaudioside A (RA:0-0.038% wt/vol) and polydextrose (P:0%-20% wt/vol) were prepared according to a Box-Behnken design. Multiple combinations of sweeteners that predicted water holding capacity (WHC) and hardness 1 (H1) like control were found using the Response Surface Methodology (RSM). P increased degrees Brix while lowered H1;whereas, E decreased WHC and increased pH. The confectionery was perceived as very healthy and with a high willingness to try. All the evaluated systems displayed a solid/gel behavior dominating the viscoelastic response. Two systems (S5 = 3.0% wt/vol S-0.019% wt/vol RA and S7 = 0.019% wt/vol RA-5.5% wt/vol E) were selected according to RSM, PCAs, MANOVA and sensory tests as both resembled the full-sucrose sample. This study proposes interesting formulations of sugar-reduced and sugar-substitute blends for being used in sweet confectioneries produced from UV-C preserved orange juice and low-methoxyl pectin, with physicochemical, rheological and sensory characteristics like the full-sucrose options. Practical applications Consumers are becoming fully aware of the significant role that food and beverages play in overall health. This trend has a decisive impact on the food industry in terms of innovation and the development of better-for-you products. The present study involves firstly, a conjoint study to investigate the interest of local consumers in a n

关键词： Wine  

摘要： It is difficult to implement the sensory quality evaluation of bulk wine before and after transportation due to geographical, time, cost, and personnel limitation. This study aimed to use the physicochemical indicators of bulk wine to construct an evaluation model of sensory quality. First, this paper designed and carried out the simulation experiment of bulk wine transportation and obtained experimental data on physicochemical and sensory indicators of wine. Afterwards, principal component analysis (PCA) was used to reduce the dimension and fuse features of the physicochemical index. Then, the extracted features were used as the input of the evaluation model, least square support vector machine (LSSVM) was constructed for sensory evaluation, and particle swarm optimization (PSO) algorithm was selected to optimize LSSVM parameters. Finally, the PCA-PSO-LSSVM model was practically applied in sampled winery. The results showed that comparing models' accuracy the PCA-PSO-LSSVM model was superior to traditional models LSSVM and PSO-LSSVM, there is significant difference between PCA-PSO-LSSVM and LSSVM, and the predictive accuracy in appearance and taste attributes was high and the overall prediction accuracy was 86.6%. The application results revealed the changes of sensory quality for bulk wine after transportation. This research provides a set of simple and feasible methods for the sensory evaluation of bulk wine. Practical applications To study the method of using the basic physicochemical index of wine to intelligently evaluate the sensory attributes of bulk wine, so as to realize the accurate evaluation of the quality of bulk wine after transportation. By comparing the comprehensive and accurate quality evaluation before and after the bulk wine transportation, it is helpful for wine companies to understand the impact of the transportation link on the wine quality, further improve the transportation method of bulk wine, and ensure the quality of the wine has importa

关键词： Proteolysis  

摘要： The aim of the current study was to assess the effects of probiotic adjuncts on physiochemical characteristics, organic acids, water-soluble nitrogen percentage (WSN%), total free amino acids (TFAA), and proteolytic patterns in buffalo milk probiotic Cheddar cheese during 120 days of ripening at 4 degrees C. Cheddar cheese was prepared with commercially available mesophilic cheese starter cultures (control), Lactobacillus acidophilus, and Bifidobacterium bifidum individually as well as in synergistic manner to prepare probiotic cheese. The results appeared with a significant difference in control and probiotic cheese with reference to citric, lactic, butyric, and acetic acids, WSN%, and TFAA production. The proteolytic pattern of probiotic bacteria modified the proteolysis and expedited the formation of bioactive peptides in Cheddar cheese. Among probiotic adjuncts, Cheddar having B. bifidum exhibited higher WSN% and TFAA as compared to the other two probiotic cheese samples. Hence, it can be concluded that B. bifidum is slightly more proteolytic as compared to other probiotic adjuncts and the incorporation of probiotic adjuncts enhanced the hydrolysis of alpha s(1-) casein in Cheddar cheese. Practical applications Bioactive peptides remain inactive within the protein molecule. When milk undergoes enzymatic hydrolysis (protein), fermentation (through the proteolytic starter), or enzymatic proteolysis, bioactive compounds become active and capable to exhibit their therapeutic potential. Probiotic adjuncts modify the proteolysis, balance bio-diversity removed by pasteurization and expedite the formation of bioactive peptides in Cheddar cheese. Regarding probiotic adjuncts, cheese serves as one of the most efficient carriers of probiotic bacteria owing to its matrix efficiency and ability to maintain the viability of bacteria and facilitate their entry into the human gut.

关键词： ultra-high pressure   angiotensin-converting enzyme inhibitory activity   Lactobacillus delbrueckii QS306   fermented milk  

摘要： The present study investigated the influence of ultra -high pressure (UHP) treatment on angiotensin-convert-ing enzyme inhibitory (ACEI) activity and quality of milk fermented with Lactobacillus delbrueckii QS306 af -ter storage. By varying treatment pressure, duration of pressure treatment, and duration of fermentation, opti-mal process parameters for the UHP treatment of milk fermented with QS306 to enhance ACEI activity were found to be 400 MPa, 10 min, and 48 h, respectively. The degree of ACE inhibition of the fermented milk was 91.63 +/- 0.02%. After UHP treatment, ACEI activity, apparent viscosity, concentrations of polypeptides and volatile aromatic substances, umami, and richness had increased significantly, bitterness and astringency were significantly reduced, and antioxidant properties were maintained. In addition, UHP fermented milk main-tained a high level of ACEI activity and good quality during storage. Thus, the data represent a valuable reference for improving the storage quality of fermented milk and research for the future development of dairy products with high ACEI activity.

关键词： Physicochemical properties  

摘要： This study was carried out to investigate the effect of different levels (0, 2, 4, 6 and 8% w/v) of sweet lupine powder (SLP) and Bifidobacterium longum ATCC 15707 on physiochemical, textural, microbiological and sensory properties of low-fat bio-Labneh samples during storage for 21 days at 5 +/- 1 degrees C. The results showed that the textural properties of low-fat bio-Labneh with a higher level of SLP (8%) were harder than those made without adding SLP. Overall acceptability of sample processed by using 2% of SLP indicated that it is more acceptable compared with other treatments. The total cell count of B. longum ATCC 15707 gradually increased until the 14(th) day of the storage period after that decreased till the end of the storage period. Furthermore, the number of viable cells of B. longum ATCC15707 remained >7 log cfu/g at the end of the storage period in the treated samples. Novelty impact statement Sweet lupine powder had a positive impact on the quality characteristics of low-fat bio-Labneh and enhanced the growth of B. longum ATCC 15707 in the Labneh matrix that resulted in a wider spectrum of health benefits of Labneh cheese to the consumers. The Labneh that was supplemented with 2% sweet lupine powder was the most acceptable treatment.

关键词： Fourier transform infrared   Nuclear magnetic resonance   Genetic variants   Milk   Micellar casein   Structure  

摘要： This study highlights differences in conformational and physicochemical characteristics of bovine skim milk and micellar casein from cows of different beta-casein phenotypes. These genetic variants have been one of the pre -dominant topics among dairy researchers due to their differences in beta-casein structure, and thus their potential effects on dairy processing and human health. For characterising differences in milk protein structure, Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (H-1 NMR) spectroscopies combined with chemo-metric analysis were used. Additionally, physiochemical properties such as mineral content, particle size, and electrostatic charge in skim milk and micellar casein samples were analysed at 4 and 20 degrees C. Results showed variation in the secondary structure of all three genetic variants independent of temperature. Moreover, the main differences involved a higher level of beta-turn and alpha-helical structures in A1/A1 beta-casein milk, while intermolecular beta-sheets were more numerous in A1/A2 beta-casein milk, whereas random or polyproline II (PPII) structures were more common in A2/A2 beta-casein milk. Temperature slightly affected these differences, which was due to the dissociation of beta-casein from the micelle at low temperature. In addition, A2/A2 beta-casein milk and its micellar casein had a larger average particle size, which resulted in a lower negative zeta-potential. The A2/A2 beta-casein samples contained greater amounts of phosphorus and less calcium compared to the other genetic variants of milk and their micellar caseins. The results also indicated that a combination of FTIR and 1H NMR spectroscopies could be used to establish conformational differences in milk and micellar caseins of different genetic variants.

关键词： Yeast  

摘要： Prolonging shelf life of fresh-cut water chestnuts (FCWC) by vitamin E (vit E) was investigated. Browning degree, decay degree, and edible quality (EQ) of FCWC were evaluated as evaluation indexes of shelf life. Meanwhile, total soluble solids concentration, titratable acid (TA) concentration, ascorbic acid (AA) concentration, hardness, ethylene concentration, polyphenol oxidase (PPO) activity, peroxidase (POD) activity, total phenols (TP) concentration, counts of thermophilic bacteria, yeasts, and molds colonies were analyzed. Shelf life of FCWC could be prolonged for 4 days by soaking them in 0.04% (v v(-1)) vit E anhydrous ethanol (1% [v v(-1)]) solution for 30 min. Vit E probably inhibited the increasing of PPO and POD activities, and the declining of TP concentration and hardness. Vit E had little effect on counts of thermophilic bacteria, yeasts, and molds colonies of FCWC. These results indicated that vit E could prolong shelf life of FCWC.