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Rafael Jiménez-flores - One of the best experts on this subject based on the ideXlab platform.
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Compositional and sensory differences of products of sweet-cream and whey Buttermilk produced by microfiltration, diafiltration, and supercritical CO21
Journal of dairy science, 2015Co-Authors: Ammar Olabi, S. Jinjarak, Rafael Jiménez-flores, John H. Walker, Hamza DaroubAbstract:Abstract The objectives of this work were to assess the compositional properties and sensory characteristics of ingredients produced by treating sweet-cream and whey-cream Buttermilks with microfiltration (MF), diafiltration (DF), and supercritical CO 2 (SFE) extraction. Sweet-cream Buttermilk (CBM) and Buttermilk resulting from churning the residual fat from whey processing (whey Buttermilk, WBM) were used. Using MF or microfiltration followed by diafiltration (MF-DF), we obtained resulting retentates that were dried and then were subjected to SFE treatment. Control Buttermilks, SFE resulting products, and MF and MF-DF SFE and all treated retentates products totaled 16 samples (2 types × 4 treatments × 2 batches). Eleven trained panelists assessed samples using descriptive analysis. Sweet-cream Buttermilk was higher in protein and lactose, whereas the WBM had similar total protein, mainly β-LG and α-LA but very low lactose. The resulting samples in order of concentration for fat and lactose were control samples>SFE treated>MF treated>DF=MF-SFE and DF-SFE. Sodium dodecyl sulfate-PAGE protein profiling showed negligible casein for WBM versus CBM and less whey proteins for CBM versus WBM, as expected. Whey Buttermilk was more yellow, salty, sour, and rancid than CBM. Regarding the treatments, significant differences were obtained on homogeneity, opacity, rancid odor, cardboard and sour flavors, sweet and salty tastes, viscosity, and mouthcoating, where SFE-treated samples showed lowest rancid odor and cardboard flavor.
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Phospholipid enrichment in sweet and whey cream Buttermilk powders using supercritical fluid extraction.
Journal of dairy science, 2009Co-Authors: A.j. Spence, Rafael Jiménez-flores, Michael C. Qian, L. GoddikAbstract:Milk fat globule membrane contains many complex lipids implicated in an assortment of biological processes. Microfiltration coupled with supercritical fluid extraction (SFE) has been shown to provide a method of concentrating these nutritionally valuable lipids into a novel ingredient. In the dairy industry there are several by-products that are rich in phospholipids (PL) such as Buttermilk, whey, and whey cream. However, PL are present at low concentrations. To enrich PL in Buttermilk powders, regular Buttermilk and whey Buttermilk (by-product of whey cream after making butter) were microfiltered and then treated with SFE after drying. The total fat, namely nonpolar lipids, in the powders was reduced by 38 to 55%, and phospholipids were concentrated by a factor of 5-fold. Characterization of the PL demonstrated specific molecular fatty amide combinations on the sphingosine (18:1) backbone of sphingomyelin with the greatest proportion being saturated; the most common were 16:0, 20:0, 21:0, 22:0, 23:0, and 24:0. Two unsaturated fatty amide chains, 23:1 and 24:1, were shown to be elevated in a whey cream Buttermilk sample compared with the others. However, most unsaturated species were not as abundant.
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Compositional and Functional Properties of Buttermilk: A Comparison Between Sweet, Sour, and Whey Buttermilk
Journal of dairy science, 2006Co-Authors: I Sodini, Pierre Morin, Ammar Olabi, Rafael Jiménez-floresAbstract:Buttermilk is a dairy ingredient widely used in the food industry because of its emulsifying capacity and its positive impact on flavor. Commercial Buttermilk is sweet Buttermilk, a by-product from churning sweet cream into butter. However, other sources of Buttermilk exist, including cultured and whey Buttermilk obtained from churning of cultured cream and whey cream, respectively. The compositional and functional properties (protein solubility, viscosity, emulsifying and foaming properties) of sweet, sour, and whey Buttermilk were determined at different pH levels and compared with those of skim milk and whey. Composition of sweet and cultured Buttermilk was similar to skim milk, and composition of whey Buttermilk was similar to whey, with the exception of fat content, which was higher in Buttermilk than in skim milk or whey (6 to 20% vs. 0.3 to 0.4%). Functional properties of whey Buttermilk were independent of pH, whereas sweet and cultured Buttermilk exhibited lower protein solubility and emulsifying properties as well as a higher viscosity at low pH (pH
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A Comparative Study of the Fractionation of Regular Buttermilk and Whey Buttermilk by Microfiltration
Journal of Food Engineering, 2006Co-Authors: Pierre Morin, Yves Pouliot, Rafael Jiménez-floresAbstract:The use of a ceramic microfiltration (MF) membrane for the fractionation of Buttermilk and whey Buttermilk obtained from pilot scale churning of cream and whey cream from industrial sources has been studied. Whey Buttermilk contained comparable amounts of phospholipids compared to regular Buttermilk but its protein content was lower due to the absence of caseins. However, it was found that lipid content of whey cream did vary significantly between lots resulting in important variations in the fat content of whey Buttermilk. A twofold MF concentration of regular Buttermilk doubled its phospholipids content whereas that of whey Buttermilk was increased by 50%. The overall efficiency of the MF processing of regular Buttermilk was limited by the amount of caseins retained by the MF membrane. Analysis of the protein profile of permeates and retentates showed that the transmission of milk fat globule membrane proteins by the MF membrane was lower when using whey Buttermilk as compared to regular Buttermilk possibly indicating the influence of casein micelles in fractionation or some structural differences between both products.
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Sensory Evaluation of Whey and Sweet Cream Buttermilk
Journal of dairy science, 2006Co-Authors: S. Jinjarak, I Sodini, Ammar Olabi, Rafael Jiménez-flores, John H. WalkerAbstract:The objective of this work was to characterize the sensory attributes of sweet cream Buttermilk (CBM) and a nontraditional product, whey Buttermilk (WBM). Whey Buttermilk results from processing whey cream into butter. The products were evaluated as fresh liquid Buttermilk obtained directly from the butter churn, and as reconstituted Buttermilk or whey Buttermilk powders. Sweet cream Buttermilk and WBM were produced either at the Dairy Products Technology Center (experimental samples, n = 2) or provided by the industry (n = 2 from 2 different commercial sources). Nine panelists were trained for twenty-four 1-h sessions; they then rated samples on a 15-cm line scale in triplicate using descriptive analysis. Data obtained were analyzed using SAS statistical software. Results indicated that WBM had similar sensory characteristics as regular CBM; however, there was a marked color difference between them. Liquid Buttermilk was not significantly different from reconstituted Buttermilk powder on many attributes. However, WBM was significantly more yellow, more sour, and more astringent than the CBM samples, and it had more cardboard flavor than the commercially produced CBM. Liquid Buttermilk was not significantly different from reconstituted Buttermilk powder on many attributes. However, some Buttermilk types had more cardboard aroma and flavor in their powdered form than in liquid form. Most attributes showed no significant differences across replicates, indicating consistency of rating. Principal component analysis showed that attributes were separated on the 2 principal components based on production site and processing form (fresh vs. reconstituted).
Vikram V. Mistry - One of the best experts on this subject based on the ideXlab platform.
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Application of Ultrafiltered Sweet Buttermilk in the Manufacture of Reduced Fat Process Cheese
Journal of Dairy Science, 1999Co-Authors: D.m. Raval, Vikram V. MistryAbstract:Reduced fat Cheddar cheeses, manufactured from pasteurized milk or from pasteurized milk supplemented with 5% ultrafiltered sweet Buttermilk, were used to manufacture reduced fat process cheeses (48% moisture, 14.8% fat). A 1:1 blend of 8- and 16-wk-old reduced fat Cheddar cheese and disodium phosphate and trisodium citrate (1:1 blend) at 0.50, 1.25, or 2.00% (wt/wt) were used for each cheese treatment. Process cheeses with added Buttermilk had lower fat contents than did the controls (14.48% vs. 15.10%) and had harder bodies because of compositional differences between Cheddar cheeses. Ash and pH were not affected by Buttermilk but increased with emulsifying salts. Hardness decreased with emulsifying salts. At similar levels of emulsifying salts process cheeses made with added Buttermilk had lower free oil and meltability than did control cheeses but had higher apparent viscosity. Meltability increased in cheeses containing Buttermilk by increasing emulsifying salts up to 1.25%. Microstructure studies revealed a finer dispersion of fat in reduced fat process cheeses from the Buttermilk treatment at 0.50 and 1.25% emulsifying salts.
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Manufacture of reduced fat Mozzarella cheese using ultrafiltered sweet Buttermilk and homogenized cream.
Journal of Dairy Science, 1999Co-Authors: V.s. Poduval, Vikram V. MistryAbstract:Reduced fat Mozzarella cheese was manufactured from 0.5% fat milk that was standardized with unhomogenized or homogenized cream, from 0.5% fat milk with 3 or 5% ultrafiltered sweet Buttermilk, or from ultrafiltered milk and homogenized cream. Curds were cheddared to a pH of 5.1 to 5.3, iced overnight, hand-stretched, brined for 10.5 h, vacuum-packaged, and stored at 4°C for 5 wk. The fat content in the cheeses ranged from 11.23 to 12.71%, and the moisture content ranged from 48.14 to 50.52%. The homogenization of the cream lowered the free oil content by 49%, and ultrafiltered Buttermilk lowered it further. The percentage of free oil increased over time in all treatments. Homogenization of the cream did not affect the meltability of cheeses, but use of ultrafiltered Buttermilk lowered meltability. Cheeses with 5% ultrafiltered Buttermilk were the softest and had the highest scores for body and texture. Storage had no effect on hardness or on body and texture. Micrographs of cheeses from homogenized cream revealed many small fat globules. Cheeses with ultrafiltered Buttermilk had a spongy and open protein matrix.
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Application of Ultrafiltered Sweet Buttermilk and Sweet Buttermilk Powder in the Manufacture of Nonfat and Low Fat Yogurts
Journal of Dairy Science, 1998Co-Authors: N. Trachoo, Vikram V. MistryAbstract:Nonfat and low fat yogurts are soft, low in solids, and exhibit whey separation unless they are heavily stabilized. In this study, the quality of nonfat (9.55 to 10.39% total solids) and low fat (13.40%) yogurts that had been fortified with ultrafiltered sweet Buttermilk or Buttermilk powder was compared with that of a control yogurt that had been fortified with nonfat dry milk. The titratable acidity and pH of low fat yogurts were higher than those of nonfat yogurts. Low fat yogurt that had been fortified with ultrafiltered sweet Buttermilk had the highest pH and titratable acidity. As shearing speed increased, the apparent viscosity of yogurts decreased, indicating a shear thinning property. At a high shearing speed, shearing time had little effect on the apparent viscosity. Nonfat yogurts with tested ingredients were similar to the control in flavor, appearance, texture, aroma, smoothness, and sourness. At a high level of fortification, ultrafiltered sweet Buttermilk lacked typical yogurt flavor but had good appearance. The microstructures of nonfat yogurts were more open than those of low fat yogurts, possibly because of the higher protein contents of the latter. Ultrafiltered sweet Buttermilk yielded the densest matrix. The addition of up to 4.8% sweet Buttermilk powder to low fat yogurt mixes yielded a soft and smooth product.
Yves Pouliot - One of the best experts on this subject based on the ideXlab platform.
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feeding Buttermilk derived choline forms during gestation and lactation modulates ex vivo t cell response in rat dams
Journal of Nutrition, 2020Co-Authors: Jessy Azarcoyabarrera, Yves Pouliot, Susan Goruk, Erin D Lewis, Jonathan M Curtis, Reid Steele, Emily Wadge, Catherine J Field, Rene L Jacobs, Caroline RichardAbstract:Background Buttermilk contains a mixture of choline forms; it is high in phosphatidylcholine (PC) and sphingomyelin (SM), which could have an impact on immune system development and function. Objectives We aimed to determine the effect of feeding Buttermilk-derived choline forms during pregnancy and lactation on maternal immune function. Methods Sprague Dawley dams (n = 8 per diet) were randomly assigned midway through pregnancy (10 d of gestation) to 1 of 3 experimental diets, containing 1.7 g/kg choline: control [100% free choline (FC)]; Buttermilk [37% PC, 34% SM, 17% glycerophosphocholine (GPC), 7% FC, 5% phosphocholine]; or placebo (50% PC, 25% FC, 25% GPC). Dams consumed the same diet until the end of the lactation period (21 d after parturition). Cell phenotypes and cytokine production by mitogen-stimulated splenocytes were measured and compared using 1-factor ANOVA test in order to asses the effect of diet on immune fuction of lactating dams (main outcome). Results After ConA stimulation, splenocytes from dams in the Buttermilk group produced more IL-2 (30%), TNF-α (30%), and IFN-γ (42%) compared with both the placebo and control diets. Placebo-fed dams had a higher proportion of CD8+ cells expressing CD152+ (22%) in spleen, and splenocytes from dams that were fed the Buttermilk and the placebo diets produced about 50% and 53% more IL-10 after LPS and OVA stimulation, respectively, compared with the control group. Conclusions Feeding Buttermilk-derived choline forms during pregnancy and lactation had a beneficial impact on the immune system of Sprague Dawley rat dams, especially on T-cell function.
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rennet coagulation properties of milk in the presence of mfgm fragments isolated from raw and pasteurised cream Buttermilk
International Dairy Journal, 2018Co-Authors: Mariepierre Gauvin, Michel Britten, Yves PouliotAbstract:Abstract Milk fat globule membrane (MFGM) fragments were isolated from raw- and pasteurised-cream Buttermilks to determine their impact on the rennet coagulation properties of milk. These MFGM fragments were recovered by ultracentrifugation after casein micelle dissociation using sodium citrate. This procedure was also applied to raw skim milk as a control. More protein was recovered from the two types of Buttermilk than from the skim milk upon centrifugation. This protein was mostly MFGM, but significant amounts of caseins and whey proteins were also recovered. This suggests that the churning of cream induces changes in these proteins, favouring their sedimentation upon ultracentrifugation. The isolated material was suspended in reconstituted skim milk, and rennet coagulation kinetics and gel contraction capacity were measured. The MFGM fragments isolated from Buttermilk impaired rennet gel formation and reduced gel contraction capacity, but these effects were not related to the cream pasteurisation treatment.
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Characterization of Buttermilk serum fractions and their effect on rennet-induced coagulation of casein micelle dispersions
International Dairy Journal, 2018Co-Authors: Mariepierre Gauvin, Yves Pouliot, Michel BrittenAbstract:Abstract Upon centrifugation of milk and Buttermilk (BM) the supernatant above the casein micelles pellet separates into three phases: a low-density opalescent fraction, a clear fraction, and a high-density opalescent (HDO) fraction. These fractions were collected and the concentrations of casein, whey and milk fat globule membrane (MFGM) proteins, fat and phospholipids determined. Reference casein micelles were pelleted from skim milk (SM) and re-suspended in the serum fractions. Rennet-induced aggregation, coagulation aptitude and gel syneresis were measured in these suspensions. Buttermilk serum fractions contained more MFGM components than SM fractions did. Overall, BM serum showed a negative impact on rennet-induced aggregation of casein micelles, gel formation and gel syneresis during cooking. This impact was greater for the HDO fraction, which contained much higher concentration of MFGM materials when isolated from Buttermilk than from milk. The negative impact of Buttermilk on rennet-induced coagulation of casein micelles was mainly attributed to the presence of tiny fat droplets and high density MFGM fragments.
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Effect of Buttermilk consumption on blood pressure in moderately hypercholesterolemic men and women.
Nutrition (Burbank Los Angeles County Calif.), 2013Co-Authors: Valérie Conway, Yves Pouliot, Patrick Couture, Sylvie Gauthier, Benoıˇt LamarcheAbstract:Abstract Objectives Milk fat globule membrane (MFGM) found in Buttermilk is rich in unique bioactive proteins. Several studies suggest that MFGM proteins possess biological activities such as cholesterol-lowering, antiviral, antibacterial, and anticancer properties, but data in humans are lacking. Furthermore, to our knowledge, no study has yet investigated the antihypertensive potential of MFGM proteins from Buttermilk. The aim of this study was to investigate the effects of Buttermilk consumption on blood pressure and on markers of the renin–angiotensin–aldosterone (RAS) system in humans. Methods Men and women (N = 34) with plasma low-density lipoprotein cholesterol Results Buttermilk consumption significantly reduced systolic blood pressure (−2.6 mm Hg; P = 0.009), mean arterial blood pressure (−1.7 mm Hg; P = 0.015), and plasma levels of the angiotensin I-converting enzyme (−10.9%; P = 0.003) compared with the placebo, but had no effect on plasma concentrations of angiotensin II and aldosterone. Conclusion Short-term Buttermilk consumption reduces blood pressure in normotensive individuals.
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Impact of Buttermilk consumption on plasma lipids and surrogate markers of cholesterol homeostasis in men and women
Nutrition metabolism and cardiovascular diseases : NMCD, 2013Co-Authors: Valérie Conway, Yves Pouliot, Sylvie F. Gauthier, Patrick Couture, Christian Richard, Benoît LamarcheAbstract:Abstract Background and aims Sphingolipids (SL) are important components of the milk fat globule membrane (MFGM) found in Buttermilk. While studies in animal models suggest that dietary SL may have cholesterol-lowering properties, data in human are lacking. The aim of this study was to investigate the impact of Buttermilk consumption on plasma lipids and surrogate markers of cholesterol (C) homeostasis in humans. Methods and results Men and women ( n = 34) with serum LDL-C P = 0.019), LDL-C (−3.1%, P = 0.057) and triacylglycerol (−10.7%, P = 0.007). Buttermilk consumption increased plasma lathosterol concentrations (+12.1%, P = 0.001), but multiple regression analysis indicated that variations in β -sitosterol concentrations ( P = 0.002) were the only significant predictor of the LDL-C response to Buttermilk consumption. Conclusion Buttermilk consumption may be associated with reduced cholesterol concentrations in men and women, primarily through inhibition of intestinal absorption of cholesterol. Registration number This trial is registered at clinicaltrials.gov as NCT01248026.
Pierre Morin - One of the best experts on this subject based on the ideXlab platform.
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effect of Buttermilk made from creams with different heat treatment histories on properties of rennet gels and model cheeses
Journal of Dairy Science, 2008Co-Authors: Pierre Morin, Yves Pouliot, Michel BrittenAbstract:Although many studies have reported negative effects on cheese properties resulting from the use of Buttermilk in cheese milk, the cause of these effects has not been determined. In this study, Buttermilk was manufactured from raw cream and pasteurized cream, as well as from a cream derived from pasteurized whole milk. Skim milks with the same heat treatments were also manufactured to be used as controls. Compositional analysis of the Buttermilks revealed a pH 4.6-insoluble protein content approximately 10% lower than that of the skim milk counterparts. Milk fat globule membrane (MFGM) proteins remained soluble at pH 4.6 in raw cream Buttermilk; however, when heat was applied to cream or whole milk before butter making, MFGM proteins precipitated with the caseins. Rennet gel characterization showed that MFGM material in the Buttermilks decreased the firmness and increased the set-to-cut time of rennet gels, but this effect was amplified when pasteurized cream Buttermilk was added to cheese milk. The microstructure of gels was studied, and it was observed that gel appearance was very different when pasteurized cream Buttermilk was used, as opposed to raw cream Buttermilk. Model cheeses manufactured with Buttermilks tended to have a higher moisture content than cheeses made with skim milks, explaining the higher yields obtained with Buttermilk. Superior retention of MFGM particles was observed in model cheeses made from pasteurized cream Buttermilk compared with raw cream Buttermilk. The results from this study show that pasteurization of cream and of whole milk modifies the surface of MFGM particles, and this may explain why Buttermilk has poor coagulation properties and therefore yields rennet gels with texture defects.
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effect of processing on the composition and microstructure of Buttermilk and its milk fat globule membranes
International Dairy Journal, 2007Co-Authors: Pierre Morin, Rafael Jimenezflores, Yves PouliotAbstract:The effect of cream pasteurization on the composition and microstructure of Buttermilk after pasteurization, evaporation and spray-drying was studied. The composition of milk fat globule membrane (MFGM) isolated from Buttermilk samples was also characterized. Pasteurization of cream resulted in higher lipid recovery in the Buttermilk. Spray-drying of Buttermilk had a significant effect on phospholipid content and composition. After spray-drying, the phospholipid content decreased by 38.2% and 40.6%, respectively in Buttermilk from raw or pasteurized cream when compared with initial Buttermilks. Pasteurization of cream resulted in the highest increase in whey protein recovery in MFGM isolates compared with all other processing steps applied on Buttermilk. A reduction in phospholipid content was also observed in MFGM isolates following spray-drying. Transmission electron microscopy of the microstructure of Buttermilks revealed extremely heterogeneous microstructures but failed to reveal any effect of the treatments.
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microfiltration of Buttermilk and washed cream Buttermilk for concentration of milk fat globule membrane components
Journal of Dairy Science, 2007Co-Authors: Pierre Morin, Michel Britten, Rafael Jimenezflores, Yves PouliotAbstract:Buttermilk, the by-product from butter manufacture, has gained much attention lately because of the application potential of its milk fat globule membrane (MFGM) components as health ingredients. Microfiltration (MF) has been studied for Buttermilk fractionation because of its ability to separate particles from dissolved solutes. However, the presence in this by-product of skim milk solids, especially casein micelles, restricts concentration of MFGM. The use of cream washed with skim milk ultrafiltrate to produce Buttermilk with lower casein content was studied as well as fractionation of this Buttermilk by MF. Results have shown that washing the cream prior to churning yields Buttermilk with 74% less protein than normal cream Buttermilk. Analysis of the protein profile of washed cream Buttermilk revealed that caseins and whey proteins were the main classes of proteins removed. The MF of washed cream Buttermilk resulted in permeation fluxes 2-fold higher than with normal cream Buttermilk. The second separation of the cream induced high losses of phospholipids in the skim phase. However, retention of remaining phospholipids in washed cream Buttermilk by the MF membrane was higher resulting in a phospholipids concentration factor 66% higher than that of normal cream Buttermilk. The results presented in this study highlight the impact of casein micelles on the separation of MFGM components as well as their effect on permeation flux during MF.
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compositional and functional properties of Buttermilk a comparison between sweet sour and whey Buttermilk
Journal of Dairy Science, 2006Co-Authors: I Sodini, Pierre Morin, Ammar Olabi, Rafael JimenezfloresAbstract:Buttermilk is a dairy ingredient widely used in the food industry because of its emulsifying capacity and its positive impact on flavor. Commercial Buttermilk is sweet Buttermilk, a by-product from churning sweet cream into butter. However, other sources of Buttermilk exist, including cultured and whey Buttermilk obtained from churning of cultured cream and whey cream, respectively. The compositional and functional properties (protein solubility, viscosity, emulsifying and foaming properties) of sweet, sour, and whey Buttermilk were determined at different pH levels and compared with those of skim milk and whey. Composition of sweet and cultured Buttermilk was similar to skim milk, and composition of whey Buttermilk was similar to whey, with the exception of fat content, which was higher in Buttermilk than in skim milk or whey (6 to 20% vs. 0.3 to 0.4%). Functional properties of whey Buttermilk were independent of pH, whereas sweet and cultured Buttermilk exhibited lower protein solubility and emulsifying properties as well as a higher viscosity at low pH (pH
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Compositional and Functional Properties of Buttermilk: A Comparison Between Sweet, Sour, and Whey Buttermilk
Journal of dairy science, 2006Co-Authors: I Sodini, Pierre Morin, Ammar Olabi, Rafael Jiménez-floresAbstract:Buttermilk is a dairy ingredient widely used in the food industry because of its emulsifying capacity and its positive impact on flavor. Commercial Buttermilk is sweet Buttermilk, a by-product from churning sweet cream into butter. However, other sources of Buttermilk exist, including cultured and whey Buttermilk obtained from churning of cultured cream and whey cream, respectively. The compositional and functional properties (protein solubility, viscosity, emulsifying and foaming properties) of sweet, sour, and whey Buttermilk were determined at different pH levels and compared with those of skim milk and whey. Composition of sweet and cultured Buttermilk was similar to skim milk, and composition of whey Buttermilk was similar to whey, with the exception of fat content, which was higher in Buttermilk than in skim milk or whey (6 to 20% vs. 0.3 to 0.4%). Functional properties of whey Buttermilk were independent of pH, whereas sweet and cultured Buttermilk exhibited lower protein solubility and emulsifying properties as well as a higher viscosity at low pH (pH
Michel Britten - One of the best experts on this subject based on the ideXlab platform.
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rennet coagulation properties of milk in the presence of mfgm fragments isolated from raw and pasteurised cream Buttermilk
International Dairy Journal, 2018Co-Authors: Mariepierre Gauvin, Michel Britten, Yves PouliotAbstract:Abstract Milk fat globule membrane (MFGM) fragments were isolated from raw- and pasteurised-cream Buttermilks to determine their impact on the rennet coagulation properties of milk. These MFGM fragments were recovered by ultracentrifugation after casein micelle dissociation using sodium citrate. This procedure was also applied to raw skim milk as a control. More protein was recovered from the two types of Buttermilk than from the skim milk upon centrifugation. This protein was mostly MFGM, but significant amounts of caseins and whey proteins were also recovered. This suggests that the churning of cream induces changes in these proteins, favouring their sedimentation upon ultracentrifugation. The isolated material was suspended in reconstituted skim milk, and rennet coagulation kinetics and gel contraction capacity were measured. The MFGM fragments isolated from Buttermilk impaired rennet gel formation and reduced gel contraction capacity, but these effects were not related to the cream pasteurisation treatment.
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Characterization of Buttermilk serum fractions and their effect on rennet-induced coagulation of casein micelle dispersions
International Dairy Journal, 2018Co-Authors: Mariepierre Gauvin, Yves Pouliot, Michel BrittenAbstract:Abstract Upon centrifugation of milk and Buttermilk (BM) the supernatant above the casein micelles pellet separates into three phases: a low-density opalescent fraction, a clear fraction, and a high-density opalescent (HDO) fraction. These fractions were collected and the concentrations of casein, whey and milk fat globule membrane (MFGM) proteins, fat and phospholipids determined. Reference casein micelles were pelleted from skim milk (SM) and re-suspended in the serum fractions. Rennet-induced aggregation, coagulation aptitude and gel syneresis were measured in these suspensions. Buttermilk serum fractions contained more MFGM components than SM fractions did. Overall, BM serum showed a negative impact on rennet-induced aggregation of casein micelles, gel formation and gel syneresis during cooking. This impact was greater for the HDO fraction, which contained much higher concentration of MFGM materials when isolated from Buttermilk than from milk. The negative impact of Buttermilk on rennet-induced coagulation of casein micelles was mainly attributed to the presence of tiny fat droplets and high density MFGM fragments.
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effect of Buttermilk made from creams with different heat treatment histories on properties of rennet gels and model cheeses
Journal of Dairy Science, 2008Co-Authors: Pierre Morin, Yves Pouliot, Michel BrittenAbstract:Although many studies have reported negative effects on cheese properties resulting from the use of Buttermilk in cheese milk, the cause of these effects has not been determined. In this study, Buttermilk was manufactured from raw cream and pasteurized cream, as well as from a cream derived from pasteurized whole milk. Skim milks with the same heat treatments were also manufactured to be used as controls. Compositional analysis of the Buttermilks revealed a pH 4.6-insoluble protein content approximately 10% lower than that of the skim milk counterparts. Milk fat globule membrane (MFGM) proteins remained soluble at pH 4.6 in raw cream Buttermilk; however, when heat was applied to cream or whole milk before butter making, MFGM proteins precipitated with the caseins. Rennet gel characterization showed that MFGM material in the Buttermilks decreased the firmness and increased the set-to-cut time of rennet gels, but this effect was amplified when pasteurized cream Buttermilk was added to cheese milk. The microstructure of gels was studied, and it was observed that gel appearance was very different when pasteurized cream Buttermilk was used, as opposed to raw cream Buttermilk. Model cheeses manufactured with Buttermilks tended to have a higher moisture content than cheeses made with skim milks, explaining the higher yields obtained with Buttermilk. Superior retention of MFGM particles was observed in model cheeses made from pasteurized cream Buttermilk compared with raw cream Buttermilk. The results from this study show that pasteurization of cream and of whole milk modifies the surface of MFGM particles, and this may explain why Buttermilk has poor coagulation properties and therefore yields rennet gels with texture defects.
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microfiltration of Buttermilk and washed cream Buttermilk for concentration of milk fat globule membrane components
Journal of Dairy Science, 2007Co-Authors: Pierre Morin, Michel Britten, Rafael Jimenezflores, Yves PouliotAbstract:Buttermilk, the by-product from butter manufacture, has gained much attention lately because of the application potential of its milk fat globule membrane (MFGM) components as health ingredients. Microfiltration (MF) has been studied for Buttermilk fractionation because of its ability to separate particles from dissolved solutes. However, the presence in this by-product of skim milk solids, especially casein micelles, restricts concentration of MFGM. The use of cream washed with skim milk ultrafiltrate to produce Buttermilk with lower casein content was studied as well as fractionation of this Buttermilk by MF. Results have shown that washing the cream prior to churning yields Buttermilk with 74% less protein than normal cream Buttermilk. Analysis of the protein profile of washed cream Buttermilk revealed that caseins and whey proteins were the main classes of proteins removed. The MF of washed cream Buttermilk resulted in permeation fluxes 2-fold higher than with normal cream Buttermilk. The second separation of the cream induced high losses of phospholipids in the skim phase. However, retention of remaining phospholipids in washed cream Buttermilk by the MF membrane was higher resulting in a phospholipids concentration factor 66% higher than that of normal cream Buttermilk. The results presented in this study highlight the impact of casein micelles on the separation of MFGM components as well as their effect on permeation flux during MF.
