查看更多>>摘要：High protein (10%) ice cream was developed at our lab using whey protein isolate. In comparison to conventional ice cream, it lacked severely in sensory attributes viz. flavour, meltdown and body and texture. Attempts were made to improve the quality attributes of high protein ice cream by increasing polysorbate 80 (PS80) level in the emulsifier blend (0.15%) from 0 to 100%. Increasing PS80 level resulted in significant (p < 0.05) decrease in consistency coefficient (0.85 +/- 0.09 Pa s(n )at 0% PS80 to 0.52 +/- 0.09 Pa s(n) at 100% PS80) and increase in loss modulus and storage modulus values. Particle size distribution revealed an increase in the mean size of fat globule clumps with increasing PS80 level (d(90) 4.03 mu m at 0% PS80 to d90 6.72 mu m at 100% PS80). Overrun and melting rate were decreased with increasing PS80. Instrumental hardness decreased when PS80 increased from 20 to 40%, however >40% PS80 led to higher hardness values. Sensory evaluation revealed that sample containing 40% PS80 in the emulsifier blend (0.06% w/w in ice cream mix) was most preferred by panelists. During storage period, high protein ice cream had lesser extent of changes in quality attributes and higher sensory acceptability than control.
查看更多>>摘要：With advantages of long shelf life and high convenience, frozen steamed bread (FSB) is suitable for commercialization and industrialization. However, FSB has to be reheated before consumption. Since steam reheating is the most commonly used method for steamed bread reheating, the quality variation of FSB during the steam reheating process was evaluated in this research. Because of the simultaneous energy and moisture transfer, both the temperature and moisture content of reheated FSB gradually increased during steaming process. Starch gelatinization and crystallinity results showed that the retrograded starch was gelatinized again during steaming process. With the increase of steam reheating time, the increase of springiness and resilience as well as the decline of hardness and chewiness indicated the improved textural properties of steamed bread. Considering the sensory evaluation, the optimal steaming time was about 12 min with a maximum sensory evaluation score of 93.3. However, the springiness, resilience and sensory evaluation results of reheated FSB were still lower than those of the fresh steamed bread. The microstructure results showed that the damaged gluten network of FSB could not be recovered by steam reheating.
查看更多>>摘要：Pea protein is often used in protein enriched diets due to its nutritional properties. Modifying its properties has been studied from many perspectives. Glycation, a non-enzymatic glycosylation reaction of proteins, is one of the modification strategies used to alter its properties like solubility and hydration ability. This study aims to investigate the extent and effect of glycation by MW heating with reducing sugars (glucose, fructose and allulose) on pea protein concentrate (PPC) by determining protein solubility and hydration behavior, free amino groups, remaining reducing sugars and glycation products. Based on the results, samples glycated by microwave heating participated in the reaction more, and this method enhanced the solubility and the hydration of PPC more than conventional heating. In fact, the solubility of 2:1.25 samples glycated by MW heating has almost doubled compared to control. Overall, the study indicated that glycation by MW heating could be used as an alternative modification method since it increased the water-PPC interactions more than water bath glycation.
Rudke, Adenilson RenatoAndrade, Katia SuzanaMazzutti, SimoneZielinski, Acacio Antonio Ferreira...
11页
查看更多>>摘要：In general, buriti seeds (BSE) and buriti shells (BSH) are discarded or used as animal feed. However, these materials may have other destinations. Therefore, the aim of this work was to obtain extracts from BSE and BSH using different extraction techniques and solvents in order to evaluate their effects on phenolic profile and antioxidant capacity of the recovered extracts. Global yield, total phenolic content (TPC), in vitro antioxidant activities, and phenolic composition accessed by LC-ESI-MS/MS were evaluated. Principal component analysis (PCA) was used as a tool to correlate the observed data. Raw material, solvent type, and extraction method influenced the obtained results mainly in relation to the phenolic composition. BSH showed higher values of global yield, antioxidant activity, and TPC, compared to BSE. Considering the 46 phenolic compounds analyzed, 28 were quantified from BSE and 33 from BSH samples. Protocatechuic acid was the major phenolic compound found in most samples, except for the BSH extract obtained with pressurized liquid extraction (PLE), which presented quercetin as the main phenolic compound. PCA analysis demonstrated that flavonoids are most associated with the BSH, while phenolic acids and phenolic aldehydes are most related to BSE samples.
Abou Elez, Rasha M. M.Elsohaby, IbrahimAbdellatif, Samah S.Nada, Hend S....
9页
查看更多>>摘要：Several species of Vibrio were identified in 4% of total examined samples with the highest isolation in human stool samples. Vibrio cholerae (V. cholerae) was highly isolated in raw milk (66.7%), whereas Vibrio parahaemolyticus (V. parahaemolyticus) was highly isolated in yoghurt (75%) out of the positive samples. The tested cholera toxin (ctxAB), haemolysin toxin (hlyA) and the toxin-coregulated pilus (tcpA) associated-virulence genes were identified in all V. cholera isolates. However, the thermostable direct haemolysin (tdh) and the thermostable direct haemolysin-related haemolysin (trh) associated-virulence genes were identified in 33.3% and 16.7% of the examined V. parahaemolyticus isolates, respectively. The multiple antibiotic resistance (MAR) index ranged from 0.15 to 0.54. Enterobacterial Repetitive Intergenic Consensus polymerase chain reaction showed a higher respective discriminatory power to V. cholerae and V. parahaemolyticus (D = 0.93 and D = 1, respectively) isolates. Lactobacillus rhamnosus (L. rhamnosus) probiotic activity on V. cholerae and V. parahaemolyticus can eliminate or significantly reduce the number of bacteria. In conclusion, most V. cholerae and V. parahaemolyticus isolates exhibited resistance to multiple antimicrobial classes. However, tetracycline, trimethoprim-sulfamethoxazole, chloramphenicol, and meropenem were recommended to treat vibriosis. L. rhamnosus could be used as an effective and applicable method for controlling antimicrobial-resistant Vibrio isolates.
查看更多>>摘要：We simulated 2 types of external injuries in fruitlets-throwing and cutting with knife, and evaluated the degree of putrefaction. The external injury-induced toxicity was determined by observing changes in the spatial structure of the cells. Next, we determined the contents of lignin and total flavonoids, and the expression of phenylpropanoid pathway-related genes encoding enzymes that alleviate peroxidation toxicity. By measuring the content of naringin, we uncovered a non-enzymatic antioxidant mechanism that eliminates excessive reactive oxygen species (ROS) in fruitlets. We also determined that external injury triggers an increased activity of antioxidant enzymes. Overall, in fruitlets, external injuries activate naringin biosynthesis in response to stress.
查看更多>>摘要：This is the first report on the structure and antioxidant property of exopolysaccharide (EPS), which was extracted from soybean protein isolate gels induced by lactic acid bacteria (LAB). EPSs were named AEPS (L. acidophilus), CEPS (L. casei), MEPS (L. mesenteroides) and LEPS (L. lactis). EPS was primarily composed of glucose, galactose and glucuronic acid, existed as random coils, and appeared as round lumps and chains. NMR showed that EPS was composed of alpha-glycosidic bond (85.0-6.0 ppm) and beta-glycosidic bonds (84.5-5.0 ppm). The peaks near at 1644 cm -1 and 590 cm-1 correspond to uronic acid and sulphate groups, respectively. CEPS had the highest ability to scavenge DPPH (58.98 +/- 1.54%), hydroxyl (64.89 +/- 1.46%) and ABTS (64.89 +/- 1.46%) free radicals. The monosaccharide composition-antioxidant activity relationships were identified using multiple linear regression analysis. This study could help promote the application of both EPS and LAB in functional soybean products.
查看更多>>摘要：Caffeic acid phenethyl ester (CAPE) is a phenolic substance with beneficial biological activities. However, low water solubility and bioavailability limit its applications. In this study, a nanoscaled targeted delivery system for CAPE was constructed using casein, sodium alginate (NaAlg), and Ca2+. The physicochemical properties, encapsulation efficiency, and morphology of the nanoparticles were characterized. The pH and storage stability, in vitro release rate, and the binding mechanisms between CAPE and casein were investigated. The results showed that Ca-casein-CAPE-NaAlg nanoparticles had a uniform particle size (211 +/- 5.1 nm), high encapsulation efficiency (96 +/- 3.98%) and loading capacity (7.01%). Fourier-transform infrared spectroscopy (FT-IR) and circular dichroism (CD) analysis confirmed the combination of CAPE and casein via hydrophobic interaction. The nanoparticles remained stable in pH 5.5-7.0 and storage at room temperature for 4 weeks. The nanoparticles effectively prevented digestion of CAPE by pepsin in vitro. Hydrophobic interactions were the main force that maintained the binding of CAPE and casein. The molar ratio of CAPE to casein in the nanoparticles was approximately 7.72-8.36:1. Therefore, the newly developed nanoparticles are expected to form delivery systems that could effectively improve the stability and bioavailability of low water-soluble bioactive compounds for applications in the functional foods and dietary supplements.
查看更多>>摘要：The water-holding capacity (WHC) in surimi gel is a key factor that influences the quality and economic value of surimi-based products. This study investigated the effect of ozone water rinsing (1, 3, 5, 7, and 10 mg/L) on the WHC, gel microstructure, capillary pressure and protein-water interactions of grass carp surimi gel. Ozonation had entrapped water molecules within the gel matrix. The treatments improved gel strength and produced a homogenous microstructure of gels with smaller pore size. The contact angles in 1-10 mg/L ozone water treatments were significantly lower than that of the non-ozonated control. The gels of the 5 and 7 mg/L ozone water treatments had significantly higher capillary pressure and lower oxygen-deuterium peak area responses after hydrogen-deuterium exchange than that of other treatments and control. The ozone water-rinsed surimi gel had better WHC due to the oxidation modifications that promoted the cross-linking of myofibrillar proteins and the formation of a more hydrophilic gel network, which allowed the gel to immobilize more water molecules.
查看更多>>摘要：This study aimed to investigate the effects of temperature and initial moisture content (M0) on the critical relative humidity (RHc) of whole-grain breakfast wheat biscuit, using the Dynamic Vapor Sorption (DVS) equilibrium and the Differential Scanning Calorimetry (DSC) methods. The effect of glass transition on physical quality of the product, as well as an optimal storage condition were also determined. The findings showed the RHc values of wheat biscuits measured by DVS were close to the relative humidity (RH) of onset glass transition temperature (Tg) measured by DSC. The RHc values indicated positive correlation with M0 and negative correlation with temperature. After the RHc values were defined, wheat biscuits (7% M0) were incubated at the conditions "below" (13.73 +/- 0.62% RH), "at" (37.79 +/- 0.46% RH) and "above" (54.66 +/- 0.68% RH) glass transition area at 20 degrees C for 15 weeks, during which texture and color of the wheat biscuits were determined. The results showed glass transition affected the biscuits predominantly on crispiness, but the effects were less pronounced on hardness and color. The findings suggested that at 20 degrees C, wheat biscuits with 7% moisture content are optimally stored at RH below 43.2% (water activity < 0.43).
NSTL
Elsevier