Carpes, Solange TeresinhaBertotto, CarlizeBilck, Ana PaulaYamashita, Fabio...
8页
查看更多>>摘要：The valorisation of agro-industrial by-products can be used as an alternative source for producing healthy food ingredients and materials. The volatile profile measured by headspace solid-phase microextraction-gas chromatography-mass spectrometry, mechanical, antioxidant and antibacterial properties of biodegradable cassava starch film extruded with the addition of different percentages of apple pomace (AP) by-product were evaluated. Characteristic volatile compounds were identified in the samples, such as a-farnesene, sulcatone and ethylphenyl propanoate. The film containing 8% AP had higher total phenolic content (3.32 mg GAE/g, Gallic acid equivalent) and antioxidant activity (2.78 mmol Trolox/g) than the control film (0.71 mg GAE/g and 1.03 mmol Trolox/g). The minimum inhibitory concentration against Staphylococcus aureus, Salmonella thyphimurium, and Escherichia coli for the films containing AP was higher than 12.5 mg/mL for all species. The results suggest that the antioxidant and antibacterial activities and mechanical properties, are dependent on the quantity of the AP added to films. Due to its antioxidant activity and mechanical properties, the AP could have real potential use as a functional ingredient in biodegradable packaging with the advantage of having good antibacterial properties.
查看更多>>摘要：Umami-taste loss and unpleasant odor are the restrictive factors of consumer acceptance of mushrooms (Flammulina velutipes). Pre- and postharvest 1-methylcyclopropene (1-MCP) treatments were applied to evaluate the sensory score, ethylene release, respiration rate, umami taste and aroma profiles in mushrooms at 10 degrees C storage. The results showed that preharvest treatment resulted in a stronger inhibition of respiration and ethylene production than postharvest treatment. Preharvest treatment also had the highest sensory score and flavor 5'-nucleotides content. The EUC values of preharvest and postharvest treatments were 10.5 and 1.4 times of CK on day 0, respectively. Preharvest treatment improved overall flavor by increasing umami scores in electronic tongue analysis and maintaining volatile compounds compared with postharvest treatment. Thus, preharvest 1-MCP treatment could be considered as an alternative approach to preserve the umami taste and aroma profiles in Flammulina velutipes.
de Lima Silva, Ivo DiegoTimeni de Moraes Filho, Luiz Emilio PessoaCaetano, Viviane Fonsecade Andrade, Michelle Felix...
9页
查看更多>>摘要：In this work, antioxidant active films of poly (vinyl alcohol) - PVA incorporated with plant extract of Caesalpinia ferrea Martius (PF) were developed. The films were prepared through the solution casting technique. The concentrations of the plant extract used in the films were 0, 1 and 5% w/w. The analyses of phenolic and flavonoid content of the extracts resulted in 464.4 and 10.54 mgEQU/g, respectively. Antioxidant activity showed an index of 42.22 and 87.90% efficiency for free radical capture (DPPH) and total antioxidant capacity (TAC) techniques, respectively. Through the results of thermal analyses, a decrease in the degree of crystallinity and enthalpy of fusion were observed. An increase in thermal stability occurred after the incorporation of plant extract in the PVA matrix. For the mechanical test, an increase in tensile strength was noted. An increase was verified for water vapor permeability with the addition of plant extract. These films showed potentially antioxidant activities. It can be concluded that the incorporation of Caesalpinia ferrea Martius extract in the PVA had promising results, therefore, presenting an alternative for conventional passive packaging.
查看更多>>摘要：The effects of nonenzymatic glycation on the binding capacity of beef myofibrillar proteins (MP) to aldehyde flavour compounds were investigated. The binding capacity was significantly increased due to the partial unfolding and flexible secondary structure of the glycated MP. Unfolding played a dominant role in binding due to the prevention of protein aggregation by steric hindrance originating from glycation with glucose (Glu), while glycation with glucosamine (GluA) induced substantial aggregation due to cross-linking. Therefore, the MP glycated with Glu had a higher binding capacity for aldehyde flavour compounds compared to MP glycated with GluA. In a competitive binding system, the MP glycated with Glu had a higher binding capacity for long-chain aldehyde flavour compounds. However, the MP glycated with GluA had a higher binding capacity for short-chain aldehyde flavour compounds, which were more likely to interact with the binding sites shielded in the protein aggregate. Nonenzymatic glycation represents a potential method to enhance the flavour intensity of meat products with high-protein levels.
查看更多>>摘要：Bacteriophage is a new biological control tool for the prevention and treatment of foodborne pathogens. In this study, an alkali-resistant phage against Escherichia coli (E. coli), named JN01, was isolated and characterized from wastewater. It exhibited lytic activities against 16 of 20 E. coli strains, 11 of which were more than three multidrug resistant strains. The biological characteristics of JN01 showed that the latent period and lysis period was 15 min and 85 min, respectively. The burst size of JN01 was about 134 PFU per infected cell. JN01 was relatively stable under stressed conditions such as temperatures (30 degrees C-70 degrees C) and pH (4-13). The genome of JN01 is 88,360-bp double-stranded DNA molecules, with a total of 130 open reading frames (ORFs) and 38.76% of G + C content. Importantly, no known virulence-associated, antibiotic and lysogeny-related genes were identified in the genome of JN01. Morphological and phylogenetic analyses confirmed that JN01 belongs to the Myoviridae. Viable cell counts of E. coli O157: H7 were reduced in milk and raw beef samples when treated with JN01 at 4 degrees C. The results indicated that JN01 could be a natural potential biological control agent for E. coli O157: H7 in foods.
查看更多>>摘要：The effects of drying (heat pump and hot air, HPD and HAD) and grinding (superfine and ordinary, SG and OG) on the content and composition of bound phenolic, morphology and microstructure of lychee juice by-production (lychee pulp pomace, LPP) were investigated. It was observed that the bound phenolic content in LPP powder dried by heat pump was higher (44.8%) than powder that was dried with hot air. It was also observed that the bound phenolic content in HPD + SG LPP powder was significantly higher (20.8%) than that of HPD + OG powder Compared with LPP powder, from the analysis of scanning electron microscopy (SEM) imagery, it was found that the LPP had become loose and broken after hydrolyzing the bound phenolic from LPP powder. The Fourier transform infrared (FTIR) spectroscopy measurements confirmed the structure had changed significantly after the loss of bound phenolic. Furthermore, the water holding capacity, water solubility and swelling capacity of HPD + SG powder was found to better than those of the HPD + OG powder. Overall, heat pump drying with superfine grinding was found to have improved the bound phenolic content and change the physical properties of the processed pulp powder, thus, providing a theoretical basis for the product development of LPP.
查看更多>>摘要：This study compared the effectiveness between sodium hypochlorite (NaOCl) and its alternatives-chlorine dioxide (ClO2) and peroxyacetic acid (PAA)-against murine norovirus-1 (MNV-1) and hepatitis A virus (HAV) contamination on carrot and lotus root. ClO2 treatment at 123-300 and 170-300 ppm for 3 min reduced MNV-1 by 1-2.51 log PFU/mL (carrot) and 1-1.83 log unit (lotus root), respectively. ClO2 treatment at > 270 ppm also achieved >1 log HAV reduction for both samples, and PAA treatment at 180-500 and 280-500 ppm for 3 min decreased MNV-1 and HAV by 1-3 and 1-2 log units, respectively. NaOCl showed the lowest antiviral effect among the three disinfectants. Enteric viruses were more difficult to inactivate on lotus root than carrot because of the starch as organic matter. No significant differences (P > 0.05) in the physicochemical qualities (surface color, hardness, pH) of carrot and lotus root were observed after treatment, even at the maximum concentration applied. Such findings suggest the use of 270 ppm ClO2 or 280 ppm PAA in the fresh root vegetable industry to control norovirus and HAV without changing food quality.
查看更多>>摘要：Lactic acid bacteria (LAB) encounter various environmental stresses (acidic, thermal, osmotic, oxidative, ethanolic and others) during food fermentation and production. Cross protection is a phenomenon commonly existed in LAB which confers LAB higher tolerance to a harsh condition through preadaptation at mild stresses. Therefore, it is necessary to summarize the researches finished in the past years. In this review, we provide a comprehensive review of the stress responses and protective mechanisms of LAB during cross protection, and particularly focus on the physiological characters (accumulation of intracellular amino acids, maintenance the homeostasis of intracellular pH, and engineering cell membrane functionality) and multi-omics analysis (genes/ proteins involved in membrane transport, energy metabolism, amino acid metabolism, stress response chaperones and cell wall/membrane biosynthesis). In addition, based on the mechanisms of cross protection, strategies to improve the robustness of LAB under various stresses were also discussed.
Jacobsen, Natashia Mai YdeNedergaard, Hanne BjornKock, AnetteCaglayan, Ibrahim...
9页
查看更多>>摘要：Probiotics have become one of the most consumed food supplements worldwide. Many probiotic strains are sensitive to low pH and bile concentrations encountered in the gastrointestinal tract upon oral ingestion. This study aimed at developing gastro-resistant probiotic granulates releasing viable cells in the small intestine. Fatty alcohols were investigated as potential coating materials. Cetostearyl alcohol was selected and combined with different plasticizers to further optimize the coating properties. Combining cetostearyl alcohol with olive oil and beeswax in selected concentrations was found promising, and the coatings were applied to L. acidophilus LA3 and B. longum BB536, using hot-melt fluid bed coating. Viability in and release from the coated probiotic granulate was investigated, using a physiological relevant in vitro model simulating conditions in the human stomach, duodenum, jejunum and ileum. L. acidophilus LA3 coated with cetostearyl alcohol and olive oil in the ratio 95:5 (w/w) resulted in significantly higher viability after simulated gastrointestinal transit, compared to the uncoated probiotic powder. Furthermore, the coating showed no release of viable cells after simulated gastric transit. Released viable cells were detected after the remaining steps in the in vitro model, indicating that the coating system provides gastric protection and release during intestinal transit.
查看更多>>摘要：This work studied the effect of ultrasound power and sodium bicarbonate (NaHCO3) concentration during soaking process on the hydration and cooking kinetics of pigeon pea (Cajanus cajan). The pigeon pea grains were hydrated using 0, 1, 1.5, and 2% m/m NaHCO3 solutions without and with ultrasound assistance (17 W/L; 40 kHz and 43 W/L; 40 kHz) at 27 degrees C. Cooking process was studied using softening kinetics. Grains were cooked in boiling water and their softening was evaluated with a texturometer. Both hydration and softening kinetics were fitted to suitable models and their parameters were used for evaluating the effect of ultrasound power and salt concentration. Ultrasound accelerated hydration kinetics but did not affect the cooking process. Soaking in NaHCO3 solution, delayed hydration kinetics, but accelerated the softening kinetics. The synergetic effect of ultrasound (17 W/L) and NaHCO3 solution (1% m/m) accelerated both hydration and cooking kinetics by approximately 3 h. In fact, hydration is a long process, which requires more than 6 h, and cooking requires boiling temperature, which increases energy use and cost. Using ultrasound technology and adding sodium bicarbonate in soaking water can improve grain processing. Studying other grains and salts solutions on hydration-cooking process in the future is recommended.
NSTL
Elsevier