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关键词： Applications   characteristics   functionality   pH-shift process   proteins  

摘要： Advanced structures of food proteins are maintained by many forces such as hydrophobic activities, electrostatic interaction, and disulphide bond interaction, which can affect their functional characteristics to a certain extent. Therefore, many approaches have been utilised to improve functional characteristics of food proteins. pH-shift process refers to the method that food proteins are treated under extreme alkaline or acid conditions followed by adjusting pH to isoelectric point or neutral pH. Many studies have showed that pH-shift process can significantly affect the functional characteristics of food proteins, for example emulsifying activities, forming property, solubility and water/oil adsorption ability. pH-shift process has been utilised to recover protein isolates from many sources including fish, fish by-products, meat processing products. Many researches have indicated that the functional and physicochemical characteristics of recovered protein isolates are significantly influenced by pH-shift process. In this paper, the latest studies regarding the functional and physicochemical characteristics of proteins treated or recovered through pH-shift process, and potential applications of obtained protein isolates in the production of the hydrolysates or used as a delivery system were reviewed.

关键词： fiber-rich ingredients   in vitrofermentation   physicochemical properties   fecal microbiota   short-chain fatty acids   lactating sow  

摘要： BACKGROUND Efficient utilization of dietary fibers (DFs) is important for optimizing feed resource utilization and animal health. The aim of the current study was to assess the effects of DFs with varying physicochemical properties (bulky, viscous, and fermentable) on fermentation kinetics and microbial composition duringin vitrofermentation by fecal inoculum from lactating sow. According to the physicochemical properties, three different DFs, lignocellulose (LC), modified cassava starch (MCS) and konjac flour (KF) were selected as bulky fiber, fermentable fiber and viscous fiber respectively. Gas production, short-chain fatty acids (SCFAs) profiles and microbial composition were monitored during the fermentation. RESULTS Results showed that the gas production in 72 h (GP(72h)) ranked as: KF > MCS > LC (P < 0.05). The halftime of asymptotic gas production ranked as: KF < MCS = LC (P < 0.001). At 36 h of fermentation, MCS group showed higher concentrations of formic acid and lactate than LC and KF groups, whereas KF group showed higher concentrations of propionate and butyrate than LC and MCS groups (P < 0.05). At 72 h of fermentation, KF group showed higher concentrations of formic acid, lactate and propionate than LC and MCS groups, whereas MCS group showed higher concentrations of acetate and butyrate than LC and KF groups (P < 0.05). At 36 h of fermentation,AnaerovibrioandErysipelatoclostridiumabundances were higher in KF group, whereasProteiniclasticumabundance was higher in MCS group. At 72 h of fermentation, the abundance ofFibrobacterin LC group was higher than that in MCS and KF groups. In addition, we also observed that the abundances of certain specific bacteria (AnaerovibrioandErysipelatoclostridium) were closely related to the SCFAs production (propionate and butyrate) at different fermentation times. CONCLUSION Collectively, the present study revealed that KF is a fast fermentation fiber which could produce propionate and butyrate rapidly, whereas LC is

关键词： guava   prebiotics   probiotics   spray dried   synbiotic  

摘要： In this work the survival of Lactobacillus plantarum in guava juice upon spray-drying process using maltodextrin (MD) and inulin (INU) as drying carriers was evaluated. The microbial viability, color, water activity (A(w)), and rehydration time in spray-dried lacto-fermented guava juice powder were evaluated at room temperature (25 degrees C) and refrigerated conditions (4 degrees C) for 45 days. Spray drying was done at inlet temperature of drying air 120 degrees C, feed flow rate 5 ml/min, hot air flow 3.0 m(3)/min, pressurized air flow 30 L/min, and outlet temperature at 75 degrees C. Results indicated that the highest survival rates of 80% for 45 days and 85% up to 15 days were observed at 4 degrees C and 25 degrees C, respectively, for powders obtained using 10% MD + 10% INU blend. Highest yield and lowest rehydration time were obtained by 20% MD. A(w) was maintained low and no color difference in the product was seen in any of the formulations. Practical Applications The practical applications of this research will help in catering the growing demand for functional foods with nondairy food matrix containing both prebiotics and probiotics (known as synbiotic). In the present work a source of prebiotic-guava and lactobacillus strain as a probiotic was used to formulate a, synbiotic beverage which was then spray dried in optimized method. Such unique combinations improve the nutritional attributes and bring forth health benefits of fruit juices, and delivers health potential from both sources (fruit juices and probiotics). This spray-dried synbiotic powder will be a preferred choice for lactose-intolerant people. The synbiotic not only help in immunomodulatory functions but also help in efficient functioning of gut microbiota which is scientifically related to many body vitals. The most critical practical challenge of preserving the needed microbial viability over shelf life is also dealt with in the present work. This consumer friendly form not only offers an ea

关键词： Low-methoxyl pectin   Set-yoghurt   Quality   Rheology   Microstructure   Sensory  

摘要： Addition of low-methoxyl pectin (LMP) was observed to reduce whey loss, improve firmness, rheology, quality and overall liking of low-fat set-yoghurt. LMP addition increased soluble solids content and resulted in higher bacterial counts (>= 10 log CFU/g), acidity, bioactivity (DPPFI. & ARTS+ mu M Tmlox/g), and lower pH of set yoghurts. A significant (p < 0.05) improvement in firmness and 16% reduction in whey loss was also observed. As per rheology studies, LMP added set yoghurts possessed higher modulus (G', G '', G*) and complex viscosity. Power law model parameters (A & z) for G* also related to the enhanced strength of yoghurt matrix on addition of LMP. The dense packing of protein gel structure along with filling action of hydrated hydrocolloid might led to moduli changes in yoghurts. Increasing slope of vertical bar G*vertical bar and dtan delta values close to zero confirmed higher gel strength of yoghurt added with higher concentrations of LMP. Microstructure revealed open porous network of casein in control, while increased cross-linking with casein or filling of cavities was observed upon addition of LMP in yoghurts. Sensory liking scores showed strong correlation with rheological parameters, while PCA confirmed the effect of LMP concentration on major quality attributes.

关键词： Cleaning  

摘要： Free fatty acidity and peroxide numbers of canola oil varied between 0.060% (deodorized oil) and 1.090% (crude oil) to 0.15 meqO(2)/kg (deodorized oil) and 3.00 meqO(2)/kg (crude oil), respectively. Also, viscosity of oil samples varied between 69.85 mPa (crude oil) and 82.25 mPa (bleached oil). Oleic and linoleic acid contents of canola oils obtained from each refining step were determined between 60.64% (deodorized oil) and 64.04% (neutralized oil) to 19.93% (neutralized oil) and 24.58% (deodorized oil), respectively. The campesterol contents of canola oils taken during rafination were determined between 6.01% (deodorized oil) and 7.90% (bleached oil) while stigmasterol contents of canola oil samples vary between 33.31% (deodorized oil) and 34.81% (bleached oil). While the B and Sn content of the oils increased during refining, Si, P, Fe, N, and Pb contents decreased significantly depending on the refining stages. The refining treatments were used to remove undesirable ingredients and produce higher quality oils in crude canola oil. Practical applications Due to their high saturated fatty acids, vegetable oils are a rich phytochemical (fatty acids, tocopherol, and sterols) sources. In addition, seeds are recognized as a good source of natural oil. The refining treatments were used to remove undesirable ingredients and produce higher quality oils in crude canola oil. Refining processes provide removing the unwanted substances, the most of vitamins, antioxidants, and sterols. The refining steps have specific functions for removing certain minor constituents.

关键词： Nutrients  

摘要： In the present study pomace obtained from orange juice extraction was dried at 70 degrees C. The pomace powder was utilized for enrichment of yoghurt at three different concentrations viz. 1%, 2%, and 3%. The physicochemical and sensory properties of the yoghurt samples were evaluated during refrigerated storage and compared with control sample. The acidity increased with increase in concentration of the pomace powder and also with duration of storage. Syneresis of the enriched samples were found to be lower than that of control, but increased with level of enrichment. During storage syneresis decreased and then increased with duration of storage. Firmness was found to decrease with level of enrichment as well as duration of storage. The consistency index increased with level of enrichment, but during storage it initially increased and then decreased. Sensory studies showed that yoghurt enriched with 1% pomace powder was acceptable to the panelists. Practical applications Milk and milk products are rich in many essential nutrients, but are devoid of certain other important nutrients like fiber and vitamin C. Enrichment of milk products with ingredients containing these nutrients will help in overcoming these deficiencies and make the milk products a wholesome food. Yoghurt is one such milk product which is considered to contain probiotic microorganisms can be consumed by lactose intolerant people as well. Enrichment of yoghurt with orange pomace powder will help in improving the nutritional value of yoghurt and will also open ways for utilization of orange pomace which is a waste material from orange juice production. As there are limited studies on utilization of orange pomace in dairy products, this study becomes important.

关键词： biodegradable packaging   collagen   methylcellulose   packaging prototypes   soluble sachets   whey protein  

摘要： Alternative materials to replace the synthetic plastics are being developed using agro-based sources, but despite their promising results, these materials still need to have their performance improved to be used in packaging. Blending different molecules can combine the properties of each polymer resulting in the overall performance improvement of the material. In the present study, collagen, whey protein, and methylcellulose were investigated in the development of individual films and blends. They were produced by the casting technique and evaluated for their packaging-related characteristics (including mechanical, barrier, and color properties), microstructure, thermal properties, and biodegradability in soil. Methylcellulose films presented excellent technological properties, such as total solubility in water, high tensile strength (15.78 MPa), transparency (30.4%), and good barrier to water vapor (0.43 g center dot mm/h center dot m(2)center dot kPa). In the blends with collagen and whey protein, it was responsible by the increase in tensile strength, barrier, and thermal properties. Collagen films presented the highest elongation at break (101.4%), while whey protein films showed lower solubility in water (28.3%). All the samples tested were completely biodegraded in 10 days in soil. Potential applications for the materials developed include soluble sachets for powdered foods due to the high solubility of some samples, as well as oil containers and capsules for instant coffee machines.

关键词： Dairy technology   Rheology   Fortification   Microencapsulation   Nutraceutical foods   Physicochemical properties  

摘要： Nanoliposomes coencapsulating curcumin and vitamin D-3(VD3) using different compositions of purified and unpurified lecithins were produced by hydration of proliposomes and characterised over 15 days of storage. The dispersions were incorporated to pineapple yoghurts produced in laboratory-scale, which were also characterised. Results showed that curcumin and vitamin D(3)were retained in the nanovesicles up to 86.1% and 94.1%, respectively. Most of the parameters assessed for the yoghurt samples were within the limits required by the Brazilian legislation and theCodex Alimentarius. Finally, the enriched product was well accepted by the panellists with the purchase intention ranging from 53 to 75%.

关键词： Flowable hemostatic agent   gelatin sponge   bleeding model   hemostasis   thrombin   biomaterial  

摘要： An effective and viable hemostatic agent is important for stopping bleeding during surgery. However, it is difficult to achieve hemostasis at uneven or deep bleeding sites using a gelatin sponge. A flowable hemostatic agent has therefore been developed by processing and improving gelatin sponge, to address bleeding under these conditions. In this study, we evaluated the efficacy, safety, and physical and chemical properties of this flowable hemostatic agent in various experiments. We examined its efficacy for stopping bleeding in a rabbit model of liver abrasionin vivo, and compared its efficacy in dynamic coagulation and erythrocyte aggregation tests with gelatin spongein vitro. We also investigated its safety in rat histocompatibility and acute systemic toxicity tests in micein vivo, and in hemolysis testsin vitro, to determine if the flowable hemostatic agent induced any pathological reactions or adverse events. In terms of its physical and chemical properties, we analyzed the morphology and chemical bonds of the flowable hemostatic agent by optical and electron microscopy and infrared spectroscopy, and its absorbency and density. The flowable hemostatic agent resulted in a shorter mean bleeding time, less bleeding, greater likelihood of successful hemostasis, and reduced clotting time compared with gelatin sponge. The flowable agent produced some changes in physical morphology, but no pathological changes or undesirable outcomes were detected. This flowable topical hemostatic agent thus provides a safe and more effective hemostatic method than gelatin sponge, and more promising results for intraoperative hemostasis, especially on uneven or deep bleeding surfaces.

关键词： High-energy compounds   Gas-solvent partition coefficients   Water-solvent partition coefficients   Vapor pressure   Enthalpy of sublimation  

摘要： We have used a variety of physicochemical systems, including water-solvent partitions, solubility in non-aqueous solvents, and HPLC and gas chromatographic retentions to obtain descriptors for nitro compounds and high energy compounds. These descriptors can then be used to predict a wide range of other physicochemical properties as well as thermodynamic and environmental properties. We illustrate the latter by predictions of the vapor pressure of sublimation, the enthalpy of sublimation and the heat capacity of sublimation at 298.15 K, and predictions of human skin permeability from water. With respect to the obtained descriptors, the most startling finding is that cyclic high energy compounds, with no 'active' hydrogen atom, have a substantial 'hydrogen bond' acidity. We suggest that this is due to electron-deficient ring systems that act as Lewis acids.