Butter Oil Research Articles

Characterization and acid-induced gelation of butter oil emulsions produced from heated whey protein dispersions

Whey protein isolate was dispersed at 4% or 8% (w/v) and heated at neutral pH to produce protein polymers. Butter oil, up to 20%, was homogenized in heated whey protein dispersions at pressure ranging from 10 to 120 MPa. Emulsion gelation was induced by acidification with glucono- δ-lactone. Whey protein polymers produced finely dispersed emulsions with fat droplet diameter ranging from 340 to 900 nm. Homogenization pressure was the main factor influencing droplet size. At low fat volume fraction, the emulsions exhibited Newtonian behaviour. As fat content increased, shear thinning behaviour developed as a result of depletion flocculation. Emulsion consistency index increased with protein and fat concentrations. Increasing homogenization pressure had no effect on Newtonian emulsions but promoted flocculation and significantly increased the consistency of high fat emulsions. Protein concentration was the main factor explaining emulsion gel hardness and syneresis. Syneresis decreased with increasing fat content in the gel.

Emulsifying properties of phospholipids in the reconstitution of cream using butter oil

Phospholipids (PL) extracted from bovine milk and soybeans were tested for their emulsifying properties in reconstituted cream using butter oil. Bovine milk PL dispersed in the oil phase were found to stabilize the cream, whereas soybean PL were found to solidify the cream. Differential scanning calorimetry was carried out on the two creams, revealing that the addition of soybean PL to the butter oil retarded the onset of crystallization during cooling, which consequently led to a lower solid fat content within the fat globules. It was suggested that the difference in the crystallization behavior of butter oil due to the addition of different PL led to the different emulsion stabilities of the reconstituted creams.

The effects of different lipid sources on performance of Koi carp (<i>Cyprinus carpio</i>) L fingerlings

A feeding experiment was carried out to determine the effect of different dietary lipid on the growth and survival of Koi carp (Cyprinus carpio) L fingerlings. Four experimental diets were formulated such that they contained groundnut oil, shea butter oil and palm oil respectively. The control contained no oil. Each diet was fed to a group of 20 fingerlings in a glass aquarium in a completely randomized design. The fingerlings with an initial average weight of 2.6 grams were fed twice daily for 58 days after which their final weights were recorded. The fingerlings fed with groundnut oil diet had the highest mean weight gain. There was no statistical difference (P>0.05) in the survival rate of the experimental fish. The highest feed conversion ratio of 41.0% was obtained with groundnut oil and closely followed by palm oil (28.0%). Keywords: groundnut oil, shea butter oil, palm oil, koi carp, fingerlings Animal Production Research Advances Vol. 1(1) 2005: 45-49

Pan-frying may induce phytosterol oxidation

The oxidative stability of different phytosterol compounds during pan-frying was evaluated. Rapeseed oil, rapeseed oil-based liquid margarine and butter oil were used as lipid matrices. Gas chromatographic–mass spectrometric analyses indicated that pan-frying may induce phytosterol oxidation but has no marked effect on phytostanol oxidation; up to 5.1% of original sitosterol and 0.1% of original sitostanol were found as oxides. High-performance size-exclusion chromatographic determinations also revealed a moderate degree of polymerization of lipid matrices. The extents of these deteriorative reactions were determined by frying temperature and time, but also by unsaturation degree and water content of the lipid matrix as well as by structure of the phytosterol compound added. The highest phytosterol oxide content was measured in saturated butter oil enriched with free phytosterols, whereas the highest matrix dimer and polymer contents were found in free phytosterol-enriched liquid margarine, which contained 20% of water.

The trans fatty acid and conjugated linoleic acid content of Fulani butter oil in Nigeria

From the milk of their cows, the Fulani pastoralists who inhabit northern Nigeria and other regions of the western Sahel produce a high-fat product called man shannu or butter oil. Since cow milk and dairy products contain a variety of trans fatty acids (TFAs) and conjugated linoleic acids (CLAs) which, depending on the particular TFA or CLA, can affect human health either adversely or positively, we were interested in determining the fatty acid composition of the milk fat of Fulani cattle and the butter oil manufactured therefrom. Milk from 12 Fulani cows and three different preparations of man shannu were analyzed for their content of TFAs and CLAs. The average fat content of the Fulani cow milk and man shannu was 3.84% and 62.5%, respectively. The milk fat contained relatively large proportions of trans vaccenic acid (mean, 3.82%) and the CLA, rumenic acid (mean, 1.35%). The percentage of the 4 major trans 18:1 isomers in man shannu was 2.23-fold higher than it was in the milk fat (10.4% versus 4.61%, respectively); in contrast, the c9,t11-18:2 percentage of man shannu was 80% lower than it was in the milk fat of the Fulani cows (0.23% versus 1.35%, respectively). Eighty percent or higher reductions were observed in the proportions of α-linolenic acid, arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid in the man shannu relative to the milk fat. These data show that: (1) the fat of Fulani cow milk and man shannu both contain large amounts of TFAs; and (2) substantial quantities of the healthful CLAs and polyunsaturated fatty acids (PUFAs) are lost during the preparation of man shannu.

Storage stability of butter oils produced from sheep’s non-pasteurized and pasteurized milk

The physical and chemical characteristics and thermal stability of butter oil produced from non-pasteurized and pasteurized sheep’s milk were studied. Thermal stability of samples was estimated by using the accelerated shelf-life testing method. Samples were stored at 60, 70 and 80 °C in the dark and the reaction was monitored by measuring peroxide, thiobarbituric acid and free fatty acid values. The peroxide and thiobarbituric acid values increased as the temperature increased. The increase of acid values of the two samples was not significant. A slight increase in free fatty acid value showed that hydrolytic reactions were not responsible for the deterioration of butter oil samples in thermal stability studies. When compared, butter oil produced from pasteurized sheep’s milk has higher thermal stability than butter oil produced from non-pasteurized sheep’s milk. Although butter oil produced from non-pasteurized milk was not exposed to any heat treatment, the shelf-life of this product was lower than the shelf-life of butter oil produced from pasteurized sheep’s milk. Therefore, heat treatment for pasteurization did not affect the thermal stability of butter oil.

Lipids and lipid oxidation with emphasis on cholesterol oxides in some Indian sweets available in London

Ghee (clarified butter oil), a major ingredient in Indian sweets, is an important source of saturated fatty acids, cholesterol and cholesterol oxidation products (COP) that are considered risk factors for atherosclerosis. The high frequency of atherosclerotic complications reported among the Indian immigrants in England prompted determination of lipids and lipid oxidation status of a ghee sample and 15 Indian sweets available in London supermarkets. The fatty acid profile of the samples shows saturated fats (about 73%), mainly composed of myristic, palmitic and stearic acids, except in two samples. There were large variations in thio-barbituric acid reacting substance values (19–260 µg/100 g) and total COP (1.4–51.2 µg/g lipids) among the sweet samples. Regular consumption of some of these sweets can be a source of considerable amounts of saturated fatty acids, cholesterol and COP in the diet and may contribute to atherosclerosis.

Effect of lipid type on water‐in‐oil‐emulsions stabilized by phosphatidylcholine‐depleted lecithin and polyglycerol polyricinoleate

Water-in-oil (W/O, 30:70) emulsions were prepared with phosphatidylcholine-depleted lecithin [PC/(PI,PE) = 0.16] or polyglycerol polyricinoleate (PGPR) as emulsifying agents by means of pressure homogenization. The effect of lipid type (medium-chain triacylglycerols, sunflower, olive, butter oil, or MCT-oil/vegetable fat blends) was investigated in relation to particle size distribution, coalescence stability and the sedimentation of the water droplets. A significant correlation (p <0.05) was observed between the interfacial pressure caused by the addition of lecithin to the pure lipids and the specific surface area of the emulsion droplets (rs = 0.700), and between the viscosity of the lipids used as the continuous phase (reflecting the fatty acid composition) and the specific surface area of the emulsion droplets (rs = 0.8459) on the other hand. Blends of vegetable fat and MCT-oil led to reduced coalescence stability due to the attachment of fat crystals to the emulsion droplets. Lecithin-stabilized W/O emulsions showed significantly higher viscosities compared to those stabilized with PGPR. It was possible to adjust the rheological properties of lecithin-stabilized emulsions by varying the lipid phase.

Kinetic properties of a commercial and a native inoculum for aerobic milk fat degradation

The aerobic fat biodegradation potential and growth characteristics of a commercial and a native inoculum (activated sludge from a dairy wastewater treatment pond), were evaluated. Batch tests were conducted with a medium based on butter oil, as the sole source of carbon, and mineral salts. Residual fat, biomass and CO 2 production were measured. Overall fat removal values were above 78% for both inocula. The growth kinetics of the commercial and native inocula followed Haldane and Monod models respectively. Both inocula showed a similar behaviour when butter oil concentration was under 360 mg/l; at higher values, the difference between the growth rates increased as a consequence of the inhibition exhibited by the commercial inoculum. The selection of an inoculum for bioaugmentation of bioreactors in the wastewater treatment requires a comprehensive knowledge of their degradation ability and tolerance to fluctuating compounds and of the operational conditions that will be utilized.

Effect of Vacuum-Condensed or Ultrafiltered Milk on Pasteurized Process Cheese

Milk was concentrated by ultrafiltration (UF) or vacuum condensing (CM) and milks with 2 levels of protein: 4.5% (UF1 and CM1) and 6.0% (UF2 and CM2) for concentrates and a control with 3.2% protein were used for manufacturing 6 replicates of Cheddar cheese. For manufacturing pasteurized process cheese, a 1:1 blend of shredded 18- and 30-wk Cheddar cheese, butter oil, and disodium phosphate (3%) was heated and pasteurized at 74°C for 2min with direct steam injection. The moisture content of the resulting process cheeses was 39.4 (control), 39.3 (UF1), 39.4 (UF2), 39.4 (CM1), and 40.2% (CM2). Fat and protein contents were influenced by level and method of concentration of cheese milk. Fat content was the highest in control (35.0%) and the lowest in UF2 (31.6%), whereas protein content was the lowest in control (19.6%) and the highest in UF2 (22.46%). Ash content increased with increase in level of concentration of cheese milk with no effect of method of concentration. Meltability of process cheeses decreased with increase in level of concentration and was higher in control than in the cheeses made with concentrated milk. Hardness was highest in UF cheeses (8.45 and 9.90kg for UF1 and UF2) followed by CM cheeses (6.27 and 9.13kg, for CM1 and CM2) and controls (3.94kg). Apparent viscosity of molten cheese at 80°C was higher in the 6.0% protein treatments (1043 and 1208 cp, UF2 and CM2) than in 4.5% protein treatments (855 and 867 cp, UF1 and CM1) and in control (557 cp). Free oil in process cheeses was influenced by both level and method of concentration with control (14.3%) being the lowest and CM2 (18.9%) the highest. Overall flavor, body and texture, and acceptability were higher for process cheeses made with the concentrates compared with control. This study demonstrated that the application of concentrated milks (UF or CM) for Cheddar cheese making has an impact on pasteurized process cheese characteristics.

Prediction of migration fat bloom on chocolate

AbstractThe objective of this study was to investigate whether it is possible to predict migration fat bloom based on measurements shortly after production. At different storage times shortly after production (0, 1, 4 h), the chocolate batches, varying in tempering method, tempering degree and amount of added butter oil, were evaluated by DSC, pNMR and texture analysis. Discriminant analysis and principal component analysis were combined to investigate the potential towards prediction. The batches were classified into groups depending on the time when white spots appeared (&lt;8 wk, 8–13 wk, &gt;13 wk). A good separation (100% correct classifications, 100% using cross‐validation) was obtained using the afore‐mentioned analyses and storage times. It was also shown that it is possible to exclude DSC analyses or analyses at 0 h storage time without compromising the classification performances too drastically. The study further elucidated that the tempering method has no significant effect on visual fat bloom development. Furthermore, undertempered chocolates bloomed quicker than well‐tempered ones, while fat bloom was delayed on overtempered chocolates. Addition of 6% butter oil promoted fat bloom development, while no significant difference was detected between chocolate with no added butter oil and chocolate with 3% butter oil added.

Acis-9,trans-11-conjugated linoleic acid-rich oil reduces the outcome of atherogenic process in hyperlipidemic hamster

Conjugated linoleic acid (CLA) mixtures demonstrated antiatherogenic properties in several animal models, including hamsters, but the mechanism of action of the main food-derived CLA isomer is unknown in this species. This study thus focused on cis-9,trans-11-CLA (rumenic acid), and its effect was compared with that of fish oil, which is known to influence several aspects of atherogenesis. Syrian hamsters were fed (for 12 wk) diets containing 20% (wt/wt) butter fat (B diet) or the same diet augmented with either 1% (wt/wt) of a cis-9,trans-11-CLA-rich oil (BR diet) or 1% (wt/wt) fish oil (BF diet). The BR diet induced the lowest aortic lipid deposition (from -30% to -45%) among the butter oil-fed hamsters. In this group, plasma also displayed a reduced non-HDL-to-HDL-cholesterol ratio (21% less than in the butter oil group) and inflammatory serum amyloid A levels (70-80%) and an improvement of anti-oxidized LDL paraoxonase activity (all P < 0.05). Compared with the B group, the beneficial effects of the BR diet could be further explained in part by preventing the high VCAM-1 expression rate, increasing (30%) ATP-binding cassette subfamily A1 expression in the aorta, and downregulating expression of inflammatory-related genes (TNF-alpha, IL-1beta, and cyclooxygenase 2, 2- to 2.8-fold, P < 0.05). This effect was partly associated with an activation of peroxisome proliferator-activating receptor (PPAR)/liver X receptor (LXR)-alpha signaling cascade. Interestingly, activation of PPAR/LXR-alpha signaling was not observed in hamsters fed the BF diet, in which the early signs of atherogenesis were increased. In conclusion, this study demonstrated that milk fat-rich cis-9,trans-11-CLA reduces the atherogenic process in hyperlipidemic hamsters.

Influence of dietary fat quantity and composition on glucose tolerance and insulin sensitivity in rats

The hypothesis that dietary fat can influence glucose tolerance and insulin sensitivity adversely or beneficially was tested in rats fed diets supplemented with variable amounts and types of fat. Two concentrations of fat (10% and 20% by weight) diets were prepared and given to male Wistar rats for 5 weeks. The animals supplemented with high fat (20%) diets showed significant increase in body and visceral fat weights as compared to rats fed low fat (10%) diets. Only the rats supplemented with a diet containing 20% butter oil showed impaired glucose tolerance and insulin insensitivity compared to normal rats. However, rats fed olive oil diets had relatively normal glucose tolerance and insulin sensitivity, although they increased body weight and visceral fats in parallel with rats fed butter oil diets. Fish oil conferred protection against obesity induced by olive oil or butter oil diets and also markedly reduced the impairment in glucose tolerance and insulin sensitivity induced by butter oil. In conclusion, these results suggest that diet therapy with fish oil or olive oil may be useful for treatment of patients with impaired glucose tolerance and/or type 2 diabetes.

Physical, chemical and stability properties of buffalo butter oil fractions obtained by multi-step dry fractionation

Chemical, physical and stability properties of buffalo butter oil fractions, obtained by stepwise crystallization at several temperatures between 15 and 40 °C, were investigated. Saponification, iodine, Reichert-Meissl, Polenske and Krishner values of low-melting fractions (LMF) were significantly higher ( P<0.05) than high-melting fractions (HMF) or the original butter oil. Cholesterol, fat-soluble vitamins (A, D and E) and lactones tended to concentrate more in LMF than middle-melting fractions (MMF) and HMF. Refractive index and specific gravity of MMF lie between those of LMF and HMF. LMF showed the lowest stability toward thermal oxidation (5.6 h) when compared to MMF (7.7–11.2 h) and HMF (11.1–16.0 h). Rate of hydrolysis of LMF was the highest (7.8 ml of 4 g/l NaOH) among all the obtained fractions, while HMF was the lowest (4.9–1.6 ml of 4 g/l NaOH). Differences in chemical and physical properties of the fractions were attributed to differences in fatty acid composition.

Lipase-Catalyzed Acidolysis of Butter Oil with Conjugated Linoleic Acid: A Kinetic Study Involving Multiple Reuse of the Immobilized Enzyme

The kinetics of the acidolysis of butter oil with conjugated linoleic acid in the presence of an immobilized lipase from Candida antarctica has been investigated. A uniresponse kinetic model was developed to characterize the rate of consumption of the conjugated linoleic acid and the total rate of release of the fatty acids formed from butter oil. In addition, a multiresponse kinetic model was developed to characterize the individual rates of release of the major fatty acid residues present in the original butter oil. Limited hydrolysis (2−4%) was also observed.

Application of phospholipids extracted from bovine milk to the reconstitution of cream using butter oil

AbstractPhospholipid (PL) extracted from bovine milk was tested for its emulsifying properties in conjunction with the reconstitution of cream using butter oil. PL from bovine milk dispersed in the oil phase was found to stabilize the cream, whereas PL extracted from soybean oil was found to solidify the cream. Different PL species purified from bovine milk PL were tested for their emulsifying properties. PC from bovine milk dispersed in butter oil was shown to stabilize the cream, whereas PE and sphingomyelin had no such effects. PC from soybean oil also was found to have emulsifying abilities. It was suggested that PC stabilized the reconstituted cream, regardless of its origin.

Cryo-TEM of isolated milk fat globule membrane structures in cream

This study has focused on structures formed through the release of lipid membrane material from milk fat globules. The aim of the study was to describe vesicles in the cream plasma and processing-induced vesicular structures in cream and buttermilk. The dairy samples were divided into three fractions through centrifugation, using D2O for density control. These fractions were examined using cryogenic transmission electron microscopy (cryo-TEM). The cream layer contains submicron-sized emulsion droplets, which are spherical and partly covered with loosely associated protein aggregates. The structures of the coalescence-induced vesicles are mostly unilamellar but bilamellar and multilamellar vesicles are also present. Some spherical structures are observed but facetted particles dominate. In the buttermilk sample, spherical and slightly deformed vesicles are visible but no facetted structures are observed. The butter oil serum sample shows interesting membrane vesicle-fat globule aggregate. These types of structures were also visible in the skim milk sample. The results show that that vesicular material may be found in a range of dairy products. To our knowledge this is the first time that the existence of these types of structure has been unambiguously demonstrated in these systems.

Fungal metabolism of butter and shea oils by Penicillium roquefortii in solid state cultures

AbstractMonoacylglycerols (monoglycerides, MAGs) were produced from butter oil and shea stearin fraction (shea oil) by two strains of Penicillium roquefortii, FRR 2456 (isolated from a spoilt melon) and Wisbey PJ (a commercial dairy strain), at pH 7.0 at 10 and 25 °C. The system was designed as a model of cheese using modified Czapek medium in solid state cultures. Shea oil with its unique fatty acid profile (stearic, oleic and palmitic acids) was used for comparison with butter oil. Yields of MAGs, which ranged from 3 to 14 g kg−1 oil, were higher with butter than with shea oil and higher when the spoilage strain FRR 2456 was used. Monoacylglycerols produced by mycelium‐bound lipases from both fungal strains were mainly sn‐1(3) or α isomers (60–70 mol%). Monopalmitin was the major MAG produced from both butter and shea oils. The production and use of MAGs alone or in combination with free fatty acids (FFAs) as food preservatives are discussed. It is implied that sn‐1(3) MAGs together with free fatty acids may be part of a natural antimicrobial system in relatively high‐pH foods such as blue mould‐ripened cheese where growth of foodborne pathogens such as Listeria monocytogenes can be a problem. Copyright © 2003 Society of Chemical Industry

Effect of Dietary Fats on Glucose Tolerance, Insulin Sensitivity and Membrane Free Fatty Acids in Rats

The present work was designed to assess the possible effects of n-3 polyunsaturated fatty acid (n-3 PUFA) as fish oil, monounsaturated fatty acid (MUFA) as olive oil (OO), saturated fatty acid (SFA) as butter oil (BO) and their combinations on glucose tolerance, insulin sensitivity and membrane free fatty acid levels. Relatively high fat (20% w/w, 40% energy) content diets were prepared and supplemented to adult male Wistar rats for 5-weeks. Body growth, intravenous glucose tolerance, insulin sensitivity and membrane free fatty acid levels in hepatic cells and erythrocytes were measured. Mean body weights and total body fats were significantly increased in both SFA and MUFA diets fed rats as compared to control and n-3 PUFA dietary groups respectively. Significant impaired glucose tolerance and insulin insensitivity was observed in rats supplemented with SFA diet as compared to all other dietary groups. However, MUFA diet has not shown any significant effect on glucose tolerance and insulin sensitivity, although it significantly induced obesity in rats. The presence of (10%) fish oil in the diet corrected the adiposity affect of SFA and significantly reduced the impairment in glucose tolerance and insulin insensitivity. In conclusion, the results provide evidence that replacing SFA with MUFA is most beneficial even though MUFA promotes the obesity. Fish oil proven the protective effect against the impairment of glucose tolerance, insulin insensitivity and obesity which induced by butter oil.

Desenvolvimento do perfil sensorial e aceitação de requeijão cremoso

O perfil sensorial de requeijao cremoso foi desenvolvido por meio da Analise Descritiva Quantitativa (ADQ) utilizando-se quatro marcas comerciais do produto. Onze termos descritivos foram desenvolvidos por uma equipe de provadores selecionados, que geraram tambem a definicao de cada termo e as amostras-referencia. Os dados obtidos foram submetidos a ANOVA, teste de Tukey e Analise de Componentes Principais. O requeijao da marca A caracterizou-se por apresentar baixa consistencia e aparencia lisa, enquanto a caracteristica predominante na marca B foi o sabor salgado muito intenso. Os produtos das marcas C e D apresentaram perfis sensoriais semelhantes entre si e distintos da marca A, por serem mais consistentes. Foi tambem realizado um teste de aceitacao utilizando escala hedonica de nove pontos. Todas as marcas apresentaram alta aceitabilidade global, nao apresentando diferenca significativa entre si. A aceitacao dos consumidores foi baseada no manuseio do produto, os quais gostaram mais das amostras mais consistentes e com menor formacao de fio.