查看更多>>摘要：Okara and brewer's spent grain (BSG) are manufacturing side streams that contribute significantly to food waste. In this study, solid-state fermentation (SSF) was performed using okara and BSG as substrates to investigate the effects of fermentation using pure and mixed cultures of Aspergillus oryzae and Bacillus subtilis. The total phenolic content (TPC), crude protein content, and total dietary fibre (TDF) of the fermented substrates were determined to evaluate their nutritional profiles. Okara fermented with a mixed culture under specific conditions produced the highest TPC values, and its TDF profile was the most ideal. These results reflected the presence of cooperative metabolism between Aspergillus oryzae and Bacillus subtilis which afforded greater enhancement in the nutritional profile of substrates compared to that of pure cultures. However, crude protein content could not be accurately determined, and more specific methods of protein quantification and optimisation of sample preparation for BSG in future work is recommended.
Martin-Hernandez, Maria Del CarmenBurnand, DavidJud, CorinnePortmann, Reto...
10页
查看更多>>摘要：The aim of the present work was to investigate the interaction of nanoparticles (NPs) with proteins during the digestion of selected food matrices. To accomplish this, magnetic silica NPs were added to skimmed milk powder (SMP), peanuts, and tofu, and the mixtures were subjected to in vitro digestion. The proteins and peptides present in the digesta, with and without NPs, and in the protein corona (PC) of NPs at the different digestion stages (oral, gastric, and intestinal) were characterised and identified with gel electrophoresis and mass spectrometry. Electrophoretic results revealed no differences in protein patterns between the control and NPs containing digesta at all digestion stages. At the end of simulated intestinal digestion, no intact food proteins were detectable, either in the food or on the NPs. At this stage, exclusively, digestive enzymes originating from pancreatin were present in the digesta and bound to NPs. Digestion-resistant peptides were detected in the digests of all studied food matrices, independently of NP presence. Moreover, on the PC of NPs digestion-resistant peptides, especially longer ones, were exclusively present after gastric and intestinal digestion stages from SMP and peanuts, but not from tofu, indicating that the PC composition was influenced by the food matrix.
查看更多>>摘要：Temperature gradients during cake baking complicate the study of leavening agent functionality, as leavening acid solubility and dissolution rate determine the moment of carbon dioxide (CO2) production. To control batter temperature, cream cake batter was baked in an electrical resistance oven (ERO). Simultaneously, CO2 release in the ERO headspace and cake height were monitored. Furthermore, CO2 production and release were linked to thermal transitions in the cake batter (DSC) and crumb structure setting (RVA). Early-acting organic acids produced high amounts of CO2 during mixing which could not be retained. This yielded low volume cakes. Sodium acid pyrophosphate and late-acting organic acids resulted in high quality cakes. However, CO2 production after crumb setting did not (further) improve cake quality, which implies suboptimal use of leavening power. This study highlights the importance of CO2 production during the early baking phase and illustrates the value of the ERO set-up for studying leavening agents.
Candido de Souza, Weysser Felipede Lucena, Fernando Azevedoda Silva, Katia GomesMartins, Laesio Pereira...
10页
查看更多>>摘要：Table grapes are widely consumed around the world due to the health benefits provided to consumers. As they are highly perishable, postharvest practices are required to maintain the quality and increase their shelf-life. This work aimed to optimize the combinations of alginate, galactomannans, and cashew gum using an experimental design of mixtures to produce edible coatings; and to evaluate their effects on the shelf-life of 'Italia' table grapes. The influence of edible coatings on the physicochemical composition (weight loss, firmness, pH, acidity, soluble solids, and color), total phenolic content, and antioxidant properties measured by ABTS, DPPH, and FRAP assays was evaluated. The edible coating composed of alginate (2.0%), galactomannans (0.5%), cashew gum (0.5%), and gelatin (2.0%) reduced weight loss in grapes and maintained their firmness and color at 9 days of storage as compared to the control. In addition, this formulation improved the content of phenolic compounds, contributing to the high antioxidant potential of coated grapes. The use of simplex-centroid mixture design proved to be an effective tool for determining different combinations of alginate, galactomannans, and cashew gum. The biopolymers demonstrated high potential to be used as edible coatings, and as an alternative to preserve the table grapes.
Izquierdo-Canas, P. M.Mena-Morales, A.Perez-Navarro, J.Garcia-Romero, E....
8页
查看更多>>摘要：The purpose of this work was to study the possibility of partially or totally replacing the use of SO2 during white wine elaboration by using saturation of grape musts with CO2 at the prefermentative stage. No differences were observed in main oenological parameters between wines from musts with and without CO2. Wines from musts with and without CO2 were submitted to an accelerated oxidation test that showed small changes in their browning capacity, without technological significance. Regarding volatile composition, the saturation of must with CO2 and the corresponding SO2 dose reduction resulted in fruit- and floral-driven wines that contribute most to the aromatic character of white wines. The sensory analysis of wines was carried out by Napping (R), showing results in accordance with the volatile composition. After 12 months of bottling, wines were stable against acetic bacteria but the absence of SO2 led to the development of malolactic fermentation in the bottle. On the basis of the current study's results, it could be suggested that this technique may be a feasible alternative that contributes to the reduction of the use SO2 doses in wines, achieving stable wines over 12 months and showing a distinctive aromatic profile.
查看更多>>摘要：This study determined the effect of relative humidity (RH) on the survival kinetics of Salmonella enterica in tree nut flours during long term storage. Three types of tree nut (almond, chestnut, and hazelnut) flours were seed inoculated with Salmonella (3-strain) to achieve about 8 log CFU/g and stored at different RH (25, 45 and 70%) conditions under ambient temperature (21 +/- 2 degrees C) storage for up to 120 days. Samples were analyzed at regular intervals (0, 7, 14, 21, 30, 60, 90, and 120 days) to determine the survivors on both selective and non-selective media. Salmonella populations were declined by 2.28-4.68 log CFU/g on the tested flours during the storage period. Compared to RH 25%, 70% showed a significant (P <= 0.05) decrease in Salmonella survival. Type of flour was found to have a variable effect on the survival of Salmonella. After 120 days of storage at 70% RH, reductions were higher on hazelnut followed by almond and chestnut flours, respectively. Bacterial population decline was found to be higher during the first 60 days of storage at 25 and 45% RH. At the same time, cell viability decreased most between 60 and 120 d in hazelnut and almond flour at 70% RH.
Li, RanYassami, ShivaKiviniemi, Eero A.Qiao, Wanjin...
9页
查看更多>>摘要：In this work, we studied the control of Listeria monocytogenes in raw chicken meat by marinating breast strips with beer containing bacteriocin leucocin C. An URA3 auxotrophic strain of probiotic yeast Saccharomyces boulardii CNCM I-745 was used as a host to express the gene lecC encoding the bacteriocin leucocin C. Secretion of leucocin C was confirmed by the inhibition against L. monocytogenes using agar well diffusion assay. The new auxotrophic host secreted leucocin C better than previously constructed wild-type strain, and therefore it was used to brew anti-listerial beer. The beer was shown to maintain its anti-listerial activity for 38 days. Chicken breast strips spiked with L. monocytogenes were then marinated with the anti-listerial beer for overnight, and the killing of L. monocytogenes was analysed. Marination with beer containing leucocin C reduced the viable cells of L. monocytogenes by about 1.6 log from (2.2 +/- 0.6) x 10(7) CFU/g on day 24, and 2.2 log from (1.8 +/- 0.3) x 10(5) CFU/g on day 38. In conclusion, the URA3 auxotrophic S. boulardii efficiently secreted the bacteriocin leucocin C, and brewing beer with this strain resulted in anti-listerial beer. Such beer is effective as a marinade in reducing the Listeria risk in chicken breast strips.
查看更多>>摘要：The present study aimed to investigate the implications of ultrasonic treatment on the conformational and functional properties of whey protein isolate (WPI). SDS-PAGE showed that ultrasonication did not change the molecular weight of WPI. FTIR spectroscopy demonstrated that sonication caused secondary structure alterations in WPI, with a reduction in alpha-helix and beta-sheet, and an enhancement in beta-turn, and random coil content. An increase in surface hydrophobicity was observed after ultrasound treatment, suggesting that modification in tertiary structure of WPI were induced by sonication. The sizes of aggregates in WPI were found reduced after sonication by the analysis of particle size distribution and scanning electron microscopy (SEM). Additionally, the foaming, emulsifying and antioxidant attributes of WPI were enhanced after treated with ultrasonication. These results suggest that ultrasonication can be used as a useful technology to modify the functional characteristics of whey proteins.
查看更多>>摘要：Soy sauce fermentation process includes koji-making and moromi fermentation stages, with the moromi stage consisting of solid (okara) and liquid (raw soy sauce) phases. Evolution of soy isoflavones in koji, okara and raw soy sauce samples was analyzed systematically, and the rule regarding the formation of soy isoflavones during the whole fermentation process was firstly figured out. Fifteen kinds of soy isoflavones were detected by UPLC-MS/MS. Following the fermentation process, the soy isoflavones profiles changed dramatically in the initial moromi stage (1 d-15 d). The concentrations of glucosides, malonylglucosides and acetylglucosides decreased and disappeared around at okara-30 d, while the concentrations of aglycones and hydroxyl aglycones increased and attained the peak at 90 d of the moromi stage. Additionally, antioxidant capacities of samples were positively correlated with the concentrations of aglycones and hydroxyl aglycones. Interestingly, in each sample, the antioxidant contribution value of hydroxydaidzein was around 100-500 times higher than that of daidzein, which demonstrated that aglycones, especially hydroxyl aglycones, were the key isoflavones contributed to the antioxidant properties of soy sauce.
查看更多>>摘要：The aroma components of Chinese sourdough steamed breads (CSSBs) play a vital role in CSSBs flavor. Fifteen aroma-active compounds of eight CSSBs fermented with sourdoughs from different regions were identified by gas chromatography-olfactometry and aroma extract dilution analysis. Odor activity values (OAVs) of (E,E)-2,4decadienal, naphthalene, 1-pentanol, 1-heptanol, 2-pentylfuran, 1-octen-3-ol were high, and these compounds provided CSSBs with the green, floral, fruity, alcoholic, nutty, sweet, fatty and mushroom odor. The aroma properties of Nanyang and Weinan samples belonged to the same category, while Taian sample had unique odor. Moreover, Xi'an sample had a rich and distinct aroma, such as strong green, floral and fatty odor. In addition, the aroma profiles of CSSBs fermented by different types of sourdough (Lao-mian starter or Jiao-zi starter) were significantly different. The OAVs and concentrations of key aroma components in CSSBs from different origins were diverse, which made different CSSBs had their own unique aroma characteristics.
NSTL
Elsevier