查看更多>>摘要：The aim of this study was to investigate the changes of individual chlorogenic acids during the coffee roasting process under authentic commercial conditions. Unique chemical reactions of caffeoylquinic acid (CQA) and dicaffeoylquinic acid (diCQA) isomers were shown in different Coffea species (C. arabica vs. C. canephora), batch sizes (1 kg vs. 20 kg) and roaster designs. Temperature determination setups of different roaster machines appeared gave varying results. Isomerization reactions of CQA in C. arabica beans were observed between the end of the drying phase and the crack reaction. Regarding C. canephora beans, the slower degradation rate of 3CQA and 4-CQA isomers after the crack reaction in contrast to C. arabica species was described for the first time.
do Vale, Rafaela BorgesClementino, Lorena SantosJanuario Ferreira, Emilly ThaynaMagnani, Marciane...
8页
查看更多>>摘要：This study aimed to evaluate the influence of using four different Saccharomyces cerevisiae strains on the phenolic compounds, antioxidant capacity (AOX), organic acid, sugar, and alcohol profiles of American Pale Ale (APA) craft beer. US-05 yeast presented a lower fermentation capacity but originated a beer with suitable ethanol content, higher lactic acid content, and lower acetic acid and succinic acid contents. Furthermore, it presented higher quantities of catechins and procyanidin B1, which resulted in a higher AOX. M15 yeast originated a beer with lower ethanol content and AOX and higher malic and formic acid contents. Beers made with BRY-97 yeast had higher ethanol content, while those made with S-04 yeast presented higher glycerol content. Several factors can affect beer quality. This study demonstrated that the type of yeast strain used in the APA craft beer brewing has a significant impact not only on the fermentative process but also on the functional characteristics of the products.
查看更多>>摘要：Films based on polysaccharides and proteins have been widely studied as possible substitutes for food packaging from fossil sources. However, its notorious sensitivity to water is still one of the primary drawbacks. In this study, sodium alginate (SA) and hydrolyzed collagen (HC) blend films containing SiO2 nanoparticles were prepared to reduce the water sensitivity. The behavior of these films regarding water vapor sorption and permeability (WVP) was reported for nano-SiO2 concentrations ranging from 2 to 10%. At each concentration evaluated, several classical mathematical models of moisture sorption isotherms were adjusted to identify the mechanisms of interactions between films and water. A reduction of approximately 8% in the film water content, and 30% reduction of WVP were observed for concentrations of nano-SiO2 higher than 6%. In addition, it was exposed that the moisture sorption exhibited a type III isotherm behavior, suggesting reduced interactions between the polymeric matrix and water vapor at low water activity. Therefore, SA/HC/SiO2 composite films could represent a simple, economical and sustainable alternative for packaging material with reduced sensitivity to water vapor.
查看更多>>摘要：Kabog millet, an indigenous gluten-free cereal grain from the Philippines, is considered an ecotype of Panicum miliaceum L. (proso millet). Phospholipids (PLs) from kabog millet could improve the texture of kabog millet food products, such as breads and cookies, by their interaction with starch. Besides their influence on baking properties of flours, PLs have been studied for their health effects. No information exists regarding the PL content of kabog millet. In our study, we analysed the content and identity of PLs from whole grain kabog millet flour. Phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI) and lysophosphatidylcholine (LPC) were found to be present in whole grain kabog millet flour. To test PL-starch interactions, rice, maize, and potato starches, and commercial amylopectin were mixed with commercial soy PC and the viscosity was measured with a rheometer. Models of PL-amylose/amylopectin complexes were deduced from rheology, iodine capacity, and isothermal titration calorimetry (ITC) experiments. PLs can bind with starch and inhibit its retrogradation by increasing the viscosity after gelatinisation. In summary, whole grain kabog millet flour contains PC, PE, PI, and LPC, which can potentially affect the retrogradation of baked products made from kabog millet flour.
查看更多>>摘要：This study focused on the covalent/noncovalent interaction between glycosylated whey protein isolate (gWPI) and tannic acid (TA) in stabilizing Pickering emulsions. The binary complex of gWPI was fabricated by protein and carbohydrate through the Maillard reaction, the interaction type of the covalent bond between the gWPI and TA was successfully prepared via an alkaline method to form the protein-carbohydrate-polyphenol ternary complex. Fluorescence spectrum results proved that the covalent bond between whey protein isolate (WPI)/gWPI and TA was stronger than the noncovalent bond. The covalent combination of TA strongly affected the fluo-rescence quenching of WPI and gWPI. Fourier transform infrared spectroscopy showed that the combination of the WPI/gWPI and TA led to changes in the secondary structure of the protein, the covalent interaction between them caused hydrogen bonds and C-O and C-N stretching vibrations. The covalent interaction in ternary complex between gWPI and TA reduced the particle size of Pickering emulsions and improved the thermal, salt ion, and storage stabilities of Pickering emulsions.
查看更多>>摘要：Pathogens can stick to the surfaces of leaves and ready-to-eat leafy greens are usually eaten without any lethal treatment to remove them. In this study, the peptide zp80 was chemically synthesized and purified. It had alpha-helix structure by circular dichroism spectroscopy analysis. zp80 reduced aerobic bacteria in ready-to-eat vegetable salad and lettuce. zp80 had MIC values of 2-8 mu M against 7 foodborne pathogens, it was 2 mu M to Listeria monocytogenes. Growth curve and time-kill curve showed that zp80 exhibited bactericidal mode with partial cell lysis. Confocal microscope indicated that zp80 was able to penetrate inside the cell membrane and distributed in cytoplasm and nucleus. Cell deformation with sunken surface was observed using scanning electron microscope. Further, results of SYTOX green and DiSC3(5) showed that zp80 had membrane depolarization caused by pore formation. After entering cytoplasm of L. monocytogenes, zp80 could bind to DNA, and then precipitated DNA. In addition, zp80 induced the production of intracellular reactive oxygen species (ROS), which played a key role on lethal effect by analysis using SYTO9 and PI. Hurdling treatment with 64 mu M zp80 reduced 4.18 log units of L. monocytogenes in fresh-cut lettuce and alleviated browning after 7-day storage.
查看更多>>摘要：Nowadays, food quality and safety issues caused by foodborne pathogens and spoilage bacteria have attracted widespread attention. This study examined effectiveness of intense pulsed light (IPL) treatment on the inactivation of seven foodborne gram-positive bacteria, including Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Enterococcus faecium, Bacillus thuringiensis, Lactobacillus brevis, and Pediococcus acidilactici. The bacteria of three survival states, including planktonic, early (8 h) and mature biofilm (48 h), and in two biofilm models, including 96 well cell culture plate and polycarbonate membrane were cultivated, which were treated by IPL with three fluences (0.0407, 0.0319 and 0.0150 J*cm(-2)) under different number of pulses at 25 degrees C and 4 degrees C. Results showed that high level inactivation under different conditions were achieved and the inactivation rate improved with the increasing of fluence and pulse number. Moreover, mature biofilm had the strongest resistance ability to IPL, followed by early biofilm, while both of them were far more resistant than planktonic state. IPL may provide a means of surface decontamination, thereby reducing the contamination of microorganisms on the food surface.
查看更多>>摘要：In this study, sodium-reduced salted salmon (SRSS) were prepared from six treatment groups formed using sodium replacers and flavor enhancers. The first three groups were prepared by replacing NaCl with 30% KCl (S2), 20% KCl + 10% CaCl2 (S3), and 50% KCl (S4), while the other three groups were prepared by the addition of the flavor enhancers of 5% yeast extract (F1), 3% lysine (F2), and 0.25% taurine (F3) along with 70% NaCl + 30% KCl. And their effects on the physicochemical properties, fatty acid, and phospholipid composition, and sensory characteristics of SRSS were investigated. The results demonstrated that replacing 30% NaCl with KCl (S2) had lower sensory damage compared with that obtained using 100% NaCl (S1). Moreover, this group exhibited higher physicochemical and lipidomic effects compared with other replacement treatments. The samples of S2 contained 0.8 mg of MDA/kg TBARS and 28.28 mu g mg(-1) phospholipids. Furthermore, the addition of yeast extract best improved the sensory defects caused by KCl. In conclusion, the results of this study can guide the production of healthier salted salmons with good sensory acceptance and low sodium content.
查看更多>>摘要：The aim of the present study was to investigate the microbial and technological characterization of barley-wheat flour (with 25%, 50%, 75% wheat flour added) breads made from hull-less barley sourdough that was prepared with a starter culture of Lb. plantarum SAB15, Lb. brevis SAB31 and S. cerevisiae SAM1-4. The yeasts isolated from spontaneous hull-less sourdough were sequenced with 26S rRNA gene via identification of the dominant species of S. cerevisiae with FTIR. Hull-less barley, with 13.6% protein, 1.47% ash, 66.15% water absorption and 21 ml sedimentation value, was added to wheat flour and protein, water absorption, and ash values decreased while sedimentation values increased. Hull-less barley-wheat bread samples containing starter culture was obtained with higher volume, specific volume and lower hardness than breads containing spontaneous culture. Especially breads with 25% and 50% barley mix were found to be the best ratios for hull-less barley bread. Although bread containing 75% and 100% barley flour scored low, those containing starter culture scored positively in terms of hardness and chewiness, and were accepted by consumers. With more barley added, there was higher a* and lower b* in the bread, while the breads with starter culture were found to be less yellow and red.
Brogan, Emily N.Park, Yong-LakMatak, Kristen E.Jaczynski, Jacek...
7页
查看更多>>摘要：Nutritional and functional properties of protein were determined for cricket, locust, and silk worm pupae powders, specifically macro-nutrient proximate composition, full amino acid composition, protein pH-solubility, and SDS-PAGE/densitometry. Cricket and locust powders contained >70 g of crude protein/100 g of sample powder (d.b. - dry basis), while silk worm pupae powder >50 g of crude protein/100 g of sample powder (d.b.). Insect powders exceeded FAO/WHO/UNU recommendations for eight of the nine essential amino acids (EAAs) for adults, but not infants. Total EAAs (21.8-23.7 g EAAs/100 g sample; d.b.) was two-times higher than FAO/ WHO/UNU recommendations for adults (12.7 g EAAs/100 g sample; d.b.), but only half for infants (46.0 g/100 g; d.b.). Nearly 70% of insect protein dissolved in alkaline pH, while only 7% at pH 4-6. SDS-PAGE/densitometry showed four protein fractions: cuticle proteins, actin-arginine kinase, hemocyanin, and myosin. SDS-PAGE/ densitometry also showed proteolysis and various distribution of protein fractions among insect powders. Protein may be efficiently isolated from insects using pH-solubility-precipitation; thus, resulting in isolates with high nutritional and functional quality.
NSTL
Elsevier