查看更多>>摘要：The characteristics of ice crystals, tissue recoverability, protein properties, and lipid oxidation were investigated to reveal the effects of salting time (0-8 h) on the frozen storage stability of tuna meat. After 2 w of frozen storage, the ice crystals in tuna meat with different salting time varied in morphological properties, evolving from large columns (0 h) to ellipsoid (0.5-3 h) and plate shape (5-8 h). The ice crystals in tuna meat with salting time of 1-3 h were more stable with the extension of frozen storage. The enhanced water-holding capacity, springiness, and cohesiveness were attributed to the modified morphology and stability of ice crystals and tissue recoverability after thawing with the formation of moderate protein-protein interactions under proper salting conditions. The declined oxidative stability of salted tuna meat was likely associated with the loss of redox balance with the extension of salting as indicated by aggravated oxidation of lipid and myoglobin and discol-oration. Salting time must be taken into account for the frozen storage stability of salted aquatic products, which could modify the microstructure of both frozen and thawed meat, protein properties, redox status of tissue, and thus quality attributes.
查看更多>>摘要：This study aimed to investigate the effect of alternative, non-wheat flours on the rheological properties of wafer batter as well as textural and sensory attributes of wafer sheet. The results indicated that the highest weight and moisture content were observed in wafers containing barley and oat flours. The addition of non-wheat flours other than maize (corn) flour led to a higher viscosity compared with the control batter. Wafer containing rye flour had the lowest hardness and the highest porosity (88.2%) among all samples. Non-wheat flours improve the nutritional value of the wafer; however, the addition of these flours to the wafer can change the rheological properties of the wafer batter and final product quality. Among the tested alternative non-wheat flours, maize flour showed the greatest similarity to wheat flour in terms of viscosity, which is the most important property of the wafer batter. According to the results, it is feasible to use non-wheat flours in a wafer with improved nutritional properties.
Arroyo-Cerezo, AlejandraJimenez-Carvelo, Ana M.Gonzalez-Casado, AntonioKoidis, Anastasios...
8页
查看更多>>摘要：Spatially offset Raman spectroscopy (SORS) technique was developed to overcome the problem with qualitative or quantitative analysis of materials through packaging. To achieve that, the instrument is configured so that the Raman scattered signal is collected at a spatially offset at some distance from the excitation laser spot on the sample. In this way, the Raman spectra are recovered from the sample's sub-surface, providing a characteristic fingerprint of the product that requires a suitable multivariate data analysis to obtain the desired information. Despite the great potential for the technique, SORS applications in the food and agriculture sector are scarce in the literature. This paper is a review of all the studies reported to date where SORS is applied to analyse different foods and beverages. All of them have presented results that demonstrate the ability of SORS to carry out rapid and non-invasive through-the-container measurements and to ensure quality control and authentication of raw materials and end products. The reviewed studies include food analysis of animal and plant origin, through the surface of the food itself, as well as through the original packaging. Using the Raman spectra data, chemometric analyses were used to group, e.g., different varieties or species of the same type of potatoes, cuts of meat or alcoholic beverages, as well as to group them according to differences such as the state of ripeness of tomatoes, or the composition of fish, meat and potatoes, among others. There is a promising future for SORS in foodstuff analysis, so the technique must continue to be studied and evolve in order to obtain the appropriate methodology and instrumentation. In addition, the development of SORS portable instruments greatly facilitates the measurement operation and opens new opportunities for applications in the field or in industrial food processing premises.
查看更多>>摘要：Dairy product spoilage by molds leads to substantial food waste and economic losses. Although some bioprotective lactic acid bacteria exhibit antifungal activity, some spoilage molds displayed extensive tolerance to these antifungal cultures and their metabolites. This study aimed to investigate some combinations of selected microbial compounds on two molds, Penicillium roqueforti ISI4 and Mucor circinelloides 01180023, previously found to be tolerant. Of the thirteen compounds tested in susceptibility test, octanoic acid (OA) exhibited the most potent antifungal activity, followed by diacetyl and 3-Phenylpropanoic acid (3-PPA). Six compounds were chosen for assessing the antifungal activity of binary combinations. OA combined with either diacetyl (COD) or 3PPA (COP) displayed synergistic antifungal effects in laboratory medium and yoghurt. Using oCelloScope, mold growth inhibition and morphological changes induced by COD and COP were observed. The increase of extracellular conductivity, intracellular materials leakage, and the propidium iodide-stained spores demonstrated the membrane was damaged. The accumulation of reactive oxygen species and the elevated malondialdehyde (MDA) content indicated the two combinations induced oxidative stress, leading to membrane lipid peroxidation. These findings highlight some combinations may exhibit synergistic effects and open up for opportunities to design culture and metabolite mixes with effect even towards very robust mold species.
Laranja, Daniela ComparsiMalheiros, Patricia da SilvaCacciatore, Fabiola AyresElias, Susana de Oliveira...
9页
查看更多>>摘要：This study aimed to evaluate the effects of antimicrobials and ultrasound (US) on the skin of chicken contaminated with Salmonella enterica. Firstly, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were determined for the antimicrobials against five strains belonging to different serovars of Salmonella or as a cocktail. Chicken skins were then artificially contaminated with Salmonella and treated with 0.07% and 0.14% peracetic acid (PAA) alone or in combination with the following antimicrobials: 3% lactic acid (LA), 3% citric acid (CA), 1% phosphoric acid (PA) and 2% sodium bisulfate (SBS) for 15 s, 5 and 30 min. Treated chicken skins showing better microbial reductions were analyzed for texture and color changes. All antimicrobial treatment combinations reduced more than 2.0 log10 CFU/g of Salmonella. There was no synergistic effect (p > 0.05) between US and antimicrobials. The treatment 0.14% PAA + 2% SBS reduced 2.8 log10 CFU/g of Salmonella. However, the skin color has changed, which is not desirable in industrial processing. Thus, the best treatment for reducing Salmonella on chicken skin without texture and color-changing was 0.07% PAA during 15 s.
查看更多>>摘要：The superheated steam technology (SHST) is a heat treatment that involves a heated saturated steam. To date, the use as cooking technology has not been evaluated in depth in terms of retention of phytochemicals. In this study, the use of SHST was compared with a conventional saturated steam (CS) oven in order to evaluate their impact on different vegetables (tomato fruits, spinach leaves and artichoke inflorescences). At biochemical level, phenolic compounds, total ascorbic acid content, some specific antioxidant compounds and, consequently, the antioxidant activity have been evaluated. Results reported a decrease of bioactivity in the tomato cooked samples (in both the heat treatments) when compared with the fresh sample. Instead, spinach leaves and artichoke inflorescences reported an increase of phytochemicals and antioxidant activity in CS or SHS samples when compared with fresh ones. Few differences in the content of bioactive compounds were observed after the use of the CS or SHS technology. Further analyses are required to verify the differences between the use of superheated or conventional steam on vegetables.
Mushtaq, MehveshGani, AdilNoor, NairahMasoodi, F. A....
10页
查看更多>>摘要：In the present study, LAB (Lactic acid bacteria) were isolated and identified from Kradi cheese. Results revealed presence of five dominant LAB viz. Lb. curvatus, Lb. sake, Lb. planatrum, Pediococcus pentosaceous and Enterococcus faecium. Among these probiotic strains, Lb. planatrum showed highest hydrophobicity and antimicrobial activity against different pathogenic strains. The cheese sample was further subjected to simulated gastrointestinal digestion (SGID) to obtain water-soluble peptide extract (WSPE). Bioactivity assays of WSPE, including, ABTS radical inhibition, reducing power, lipid peroxidation inhibition, alpha-glucosidase inhibition and alpha-amylase inhibition increased significantly from 12.03 to 58.89%, 14.85-55.72%, 14.67-52.43%, 15.55-57.65%, 17.88 %-59.33%, respectively from 0 to 420 min of digestion. Anti-cancer and anti-hypertensive activity of WSPE increased significantly from 13.44 to 69.39% and 19.75-71.23% upon digestion in simulated gastrointestinal juice (SGIJ). The overall results suggest that bioactivity of sample enhanced upon digestion validating Kradi cheese as a potential source of bioactive peptides and probiotics and therefore, may be categorized as a functional food.
查看更多>>摘要：While atmospheric cold plasma has successfully inactivated biohazardous proteinaceous molecules (unwanted enzymes, prions, and allergens) and modified proteins with improved functionality, few studies have characterized plasma-protein interactions. This study investigates the physicochemical interactions, structural alteration, and reaction mechanisms of bovine serum albumin (BSA) subjected to high voltage atmospheric cold plasma (HVACP) generated by a dielectric barrier discharge in sealed bags packed with air or modified air (65% O2, 30% N2, 5% CO2). Treating 10 mL of BSA solution (50 mg/mL) with HVACP for 60 min changed the sample from transparent to yellow and induced protein precipitation. HVACP also induced protein unfolding, altered secondary structure (27% loss of alpha-helix), and increased disorder structure (10% increase of random coil). HVACP-treated protein increased in average size from 10 nm to 113 mu m, with a broader size distribution after 60 min of HVACP treatment. SDS-PAGE and mass spectrometry showed the formation of new peptides from 1 to 10 kDa, indicating plasma-triggered peptide bond cleavage. Chemical analysis and mass spectrometry demonstrated oxidation and deamidation in HVACP-treated samples. This study illustrates that interactions between HVACPinduced reactive species and proteins may introduce structural alterations, protein aggregation, peptide cleavage, and side-group modifications to proteins in aqueous conditions.
查看更多>>摘要：The optimal conditions for preparation of egg white peptides-calcium chelate (EWPs-Ca) were determined by response surface methodology (RSM). Under the optimal condition (mass ratio of peptide: calcium of 4:1 at 53 degrees C and pH 8.2 for 30 min), the calcium content of EWPs-Ca was 44.1 mg/kg. The results of Ultraviolet-Visible absorption spectroscopy (UV) and Fourier transform infrared spectroscopy (FTIR) indicated that the carboxyl oxygen and amino nitrogen atoms of the egg white peptides (EWPs) may chelate with calcium during the chelation. Amino acid analysis suggested that glutamate, aspartic acid, cysteine, threonine, glycine and lysine played important roles during the chelation. The scanning electron microscopy showed that due to EWPs combined with calcium, the structure of EWPs-Ca became loose porous sponge. Moreover, the amount of transferred calcium of EWPs-Ca was 46.18 +/- 2.12, 63.86 +/- 0.36, 106.91 +/- 0.44, 123.61 +/- 1.59 mu g/mL at 30, 60, 120, 180 min in Caco-2 cell monolayers, respectively. Compared with the blank control, the proliferation rate of Human fetal osteoblast (HFOB) cells reached the maximum value of 119.55 +/- 1.36%, 110.20 +/- 1.56% and 112.58 +/- 1.62% at 24, 48 and 72 h, respectively and EWPs-Ca also improved the activity of alkaline phosphatase (ALP).
查看更多>>摘要：The aim of this study was to analyze changes in the surface structure and the inner microstructure of durum wheat pasta during the boiling process. Dried pasta was boiled for 1, 4, 7, or 10 min, and the structure of dried and boiled pasta was observed using polarizing light, laser, and fluorescence microscopy. The degree of gelatinization was measured by polarized light microscopy as well as the beta-amylase-pullulanase method. The degree of gelatinization was shown to be larger when evaluated by polarized light microscopy. The surface roughness was evaluated by laser microscopy. The surface roughnesses of dried (non-boiled) pasta and boiled pasta showed different characteristics, and the calculation and analysis of parameters relating to surface roughness indicated that the surface of pasta becomes more uneven as boiling time increases. In principal component analysis of surface roughness, principal components 1 and 2 explained 71.7% of total variance. Principal component 1 mainly reflected the peak frequency and height, and principal component 2 mainly reflected the peak interval. We confirmed by fluorescence microscopy that starch granules began to swell from the outer periphery of the pasta during boiling, and the proportion of gluten network on the outer circumference structure clearly decreased.
NSTL
Elsevier