Recovery of the butterfat in waste ice cream may be an opportunity to mitigate food and economic loss. Previous efforts to recover such fat have succeeded in producing a fat-enriched fraction but have not succeeded in demulsifying the fat. In the present study, a method involving a sequence of emulsion-breaking steps is shown to be effective for releasing a majority of the fat from waste ice cream as free, unemulsified oil.
View Article and Find Full Text PDFis a Gram-positive bacterium causing listeriosis, a severe infection responsible for significant morbidity and mortality globally. Its persistence on food processing surfaces via biofilm formation presents a major challenge, as conventional sanitizers and antimicrobials exhibit limited efficacy against biofilm-embedded cells. This study investigates a novel approach combining an engineered polysaccharide-degrading enzyme (CAase) with a bacteriocin (thermophilin 110) produced by .
View Article and Find Full Text PDFIce cream manufacture commonly results in the accumulation of wasted product that contains valuable food-grade quality components, including fat, carbohydrates, and protein. Methods have been developed for recovering the fat from this waste stream, but this results in the generation of a co-product rich in fermentable carbohydrates. This study aimed to investigate the potential for using this co-product as a fermentation substrate for production of antimicrobial peptides, called bacteriocins, by dairy starter cultures.
View Article and Find Full Text PDFIn the present research, we investigated changes in the gut metabolome that occurred in response to the administration of the strain GG (LGG). The probiotics were added to the ascending colon region of mature microbial communities established in a human intestinal microbial ecosystem simulator. Shotgun metagenomic sequencing and metabolome analysis suggested that the changes in microbial community composition corresponded with changes to metabolic output, and we can infer linkages between some metabolites and microorganisms.
View Article and Find Full Text PDFMilk oligosaccharides (MOs) can be prebiotic and antiadhesive, while fatty acids (MFAs) can be antimicrobial. Both have been associated with milk microbes or mammary gland inflammation in humans. Relationships between these milk components and milk microbes or inflammation have not been determined for cows and could help elucidate a novel approach for the dairy industry to promote desired milk microbial composition for improvement of milk quality and reduction of milk waste.
View Article and Find Full Text PDFIntroduction: Following consumption of milk, lactose, a disaccharide of glucose and galactose, is hydrolyzed and absorbed in the upper gastrointestinal tract. However, hydrolysis and absorption are not always absolute, and some lactose will enter the colon where the gut microbiota is able to hydrolyze lactose and produce metabolic byproducts.
Methods: Here, the impact of lactose on the gut microbiota of healthy adults was examined, using a short-term, strategy where fecal samples harvested from 18 donors were cultured anaerobically with and without lactose.
Electrospinning has been proposed as a method to encapsulate and preserve bioactive compounds in nanofibrous mats to ensure their delivery and associated health benefits when consumed directly or added to a food formulation. In previous work, we demonstrated the production of edible fibers to form mats of both calcium (CaCAS) and sodium (NaCAS) caseinate-pullulan (PUL), with the polysaccharide PUL added as a carrier to facilitate molecular entanglement for fiber formation. In this study, we determined the viability of the probiotic bacteria, GG (LGG), used as a model bacterium, in mats of CaCAS-PUL and NaCAS-PUL.
View Article and Find Full Text PDFBeta-cyclodextrin (β-CD) has been shown to successfully lower the cholesterol content of dairy products, such as butter, but the process tends to negatively impact the overall quality and consistency. In this study, β-sitosterol, which is similar in structure as cholesterol, was reacted with oleic acid to form β-sitosteryl oleate (BSO), and this was used to improve the consistency of reduced-cholesterol butter. The reaction was catalyzed by sodium bisulfate (2%, w/w) at 140 °C, and the highest degree of esterification (94.
View Article and Find Full Text PDFLeaf extracts of , composed of more than 10 steviol glycosides (SGs), are used as non-nutritive, table sugar (sucrose) alternatives due to their high level of sweetness and low caloric impact. They are often combined with the sugar alcohol erythritol to increase volume and reduce aftertaste. Little is known of the impact of sugar alternatives on the human gut microbiota in terms of the diversity, composition, and metabolic products.
View Article and Find Full Text PDFAs innovative processing equipment is introduced to milk processing, it is essential to determine its effect on milk aroma, a critical factor in consumer acceptance of the final dairy product. Microfluidization is known to cause severe high-pressure homogenization of milk fat and, although severe processing is known to release undesired aromas, no information is available on the levels of the volatile compounds in milk immediately after microfluidization. We hypothesized that microfluidization would alter levels of volatile compounds in milk that may affect aroma.
View Article and Find Full Text PDFInnovative processing technologies, such as ultrasonication, can change the properties of milk, allowing for the improvement or development of dairy foods. Yet taking bench-scale equipment to pilot plant scale has been challenging. Raw milk, standardized to 3% fat and warmed to inlet temperatures of 42 or 54°C, was exposed to continuous, high-intensity, low-frequency ultrasonication (16/20 kHz, 1.
View Article and Find Full Text PDFThe human gut microbiota plays a vital role in both human health and disease. Studying the gut microbiota using an in vivo model, is difficult due to its complex nature, and its diverse association with mammalian components. The goal of this protocol is to culture the gut microbiota in vitro, which allows for the study of the gut microbiota dynamics, without having to consider the contribution of the mammalian milieu.
View Article and Find Full Text PDFThe Twin Simulator of the Human Intestinal Microbial Ecosystem (TWINSHIME®) was initially developed to study the luminal gut microbiota of the ascending (AC), transverse (TC), and descending (DC) colon regions. Given the unique composition and potential importance of the mucosal microbiota for human health, the TWINSHIME was recently adapted to simulate the mucosal microbiota as well as the luminal community. It has been previously demonstrated that the luminal community in the TWINSHIME reaches a steady state within two weeks post inoculation, and is able to differentiate into region specific communities.
View Article and Find Full Text PDFIn this study, the effect of the flavanone naringenin on the growth and genetic expression of the commensal gut microbes, , , and , was analyzed. Analysis of growth curves revealed that was unaffected by naringenin, was slightly enhanced by naringenin, and was severely inhibited by naringenin. Changes in genetic expression due to naringenin were determined using single-molecule RNA sequencing.
View Article and Find Full Text PDFThis work examines the use of mild heat treatments in conjunction with 2-pass microfluidization to generate cheese milk for potential use in soft cheeses, such as Queso Fresco. Raw, thermized, and high temperature, short time pasteurized milk samples, standardized to the 3% (wt/wt) fat content used in cheesemaking, were processed at 4 inlet temperature and pressure conditions: 42°C/75 MPa, 42°C/125 MPa, 54°C/125 MPa, and 54°C/170 MPa. Processing-induced changes in the physical, chemical, and microbial properties resulting from the intense pressure, shear, and cavitation that milk experiences as it is microfluidized were compared with nonmicrofluidized controls.
View Article and Find Full Text PDFMaterials (Basel)
September 2016
We report the successful preparation of reinforced electrospun nanofibers and fibrous mats of polyvinyl alcohol (PVA) via a simple and inexpensive method using stable tannic acid (TA) and ferric ion (Fe) assemblies formed by solution mixing and pH adjustment. Changes in solution pH change the number of TA galloyl groups attached to the Fe from one (pH < 2) to two (3 < pH < 6) to three (pH < 7.4) and affect the interactions between PVA and TA.
View Article and Find Full Text PDFApigenin is a major dietary flavonoid with many bioactivities, widely distributed in plants. Apigenin reaches the colon region intact and interacts there with the human gut microbiota, however there is little research on how apigenin affects the gut bacteria. This study investigated the effect of pure apigenin on human gut bacteria, at both the single strain and community levels.
View Article and Find Full Text PDFWe compared the effects of homogenization and heat processing on the chemical and in vitro digestion traits of milk from organic and conventional herds. Raw milk from organic (>50% of dry matter intake from pasture) and conventional (no access to pasture) farms were adjusted to commercial whole and nonfat milk fat standards, and processed with or without homogenization, and with high-temperature-short-time or UHT pasteurization. The milk then underwent in vitro gastrointestinal digestion.
View Article and Find Full Text PDFDevelopment of reduced-sodium cheese to meet the demands of consumers concerned about sodium levels in their diet is challenging when a high-moisture, higher pH, fresh cheese, such as Queso Fresco (QF), depends on its NaCl salt content to obtain its signature flavor and quality traits. This study evaluated the effects of different Na-K salt blends on the compositional, sensorial, microbial, functional, and rheological properties of QF stored for up to 12 wk at 4°C. Queso Fresco curd from each vat was divided into 6 portions and salted with different blends of NaCl-KCl (Na-K, %): 0.
View Article and Find Full Text PDFThere is an increasing interest in applying the technology of electrospinning for making ultrafine fibers from biopolymers for food-grade applications, and using pullulan (PUL) as a carrier to improve the electrospinnability of proteins and other naturally occurring polyelectrolytes. In this study, PUL solutions containing NaCl or Na₃C₆H₅O₇ at different concentrations were electrospun. The inclusion of salts interrupted the hydrogen bonding and altered solution properties, such as viscosity, electric conductivity, and surface tension, as well as physical properties of fibers thus obtained, such as appearance, size, and melting point.
View Article and Find Full Text PDFCellulose acetate (CA) fibrous mats with improved mechanical and antioxidant properties were produced by a simple, scalable and cost-effective electrospinning method. Fibers loaded with small amounts of TA-Fe complexes showed an increase in tensile strength of ∼117% when compared to that of neat CA and were more resistant than those loaded with TA alone. The water uptake of the fibers increased upon TA or TA-Fe incorporation while their thermal behavior was only slightly affected.
View Article and Find Full Text PDFQuercetin is one of the most abundant polyphenols found in fruits and vegetables. The ability of the gut microbiota to metabolize quercetin has been previously documented; however, the effect that quercetin may have on commensal gut microbes remains unclear. In the present study, the effects of quercetin on the commensal gut microbes Ruminococcus gauvreauii, Bifidobacterium catenulatum and Enterococcus caccae were determined through evaluation of growth patterns and cell morphology, and analysis of genetic expression profiles between quercetin treated and non-treated groups using Single Molecule RNA sequencing via Helicos technology.
View Article and Find Full Text PDFProbiotics have shown beneficial effects on health and prevention of diseases in humans. However, a concern for application of probiotics is the loss of viability during storage and gastrointestinal transit. The aim of this study was to develop an encapsulation system to preserve viability of probiotics when they are administrated orally and apply Lactobacillus rhamnosus GG (LGG) as a probiotic model to evaluate the effectiveness of this approach using in vitro and in vivo experiments.
View Article and Find Full Text PDFCentral to commercial fluid milk processing is the use of high temperature, short time (HTST) pasteurization to ensure the safety and quality of milk, and homogenization to prevent creaming of fat-containing milk. Ultra-high-temperature sterilization is also applied to milk and is typically used to extend the shelf life of refrigerated, specialty milk products or to provide shelf-stable milk. The structures of the milk proteins and lipids are affected by processing but little information is available on the effects of the individual processes or sequences of processes on digestibility.
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