Oxidation and textural characteristics of butter and ice cream with modified fatty acid profiles

Effect of temperature on the rheological, textural, and sensory properties of butters from New Zealand market

Texture and sensory studies at various temperatures are important in evaluating and improving the functionality of butter. While literature is scarce, we evaluated and compared the effect of temperature (5-25°C) on the texture, rheological and sensory properties of commercial butter samples (salted, unsalted, cultured, and spreadable) from the New Zealand market. In addition, the instrumental analyses were compared with the sensory evaluation, to understand the possibility of using instrumental analysis to evaluate consumer liking for different butters. Butter type, temperature, and their type-temperature interaction exhibited significant differences for all instrumental textural parameters. As expected, higher temperature produced softer butter that was more spreadable, liquid-like, less adhesive, less cohesive, had lower storage modulus (G') and lower loss modulus (G″) with the melting of milk fat crystals; however, the rate of change varied for the different butter samples. We have established meltability as the parameter for evaluating butter selection for different applications. The spreadable butter sample exhibited the lowest hardness and G', and highest spreadability (p < .05) at all temperatures, owing to its low solid fat content and the abundance of low-melting triglycerides. The cultured butter sample had the highest melting point, owing to compositional differences. The instrumental and sensory texture analyses were highly correlated, indicating the comparative effectiveness of both approaches for studying the effects of different temperatures on butter textural properties. Overall, our findings provide detailed reference to the dairy industry for butter manufacture, considering variation in fatty acid composition, texture analysis, rheology, and sensory analysis, over the range of storage/usage temperatures.

Single-step genome-wide association for selected milk fatty acids in Dual-Purpose Belgian Blue cows

The aim of this study was to estimate genetic parameters and identify genomic regions associated with selected individual and groups of milk fatty acids (FA) predicted by milk mid-infrared spectrometry in Dual-Purpose Belgian Blue cows. The used data were 69,349 test-day records of milk yield, fat percentage, and protein percentage along with selected individual and groups FA of milk (g/dL milk) collected from 2007 to 2020 on 7,392 first-parity (40,903 test-day records), and 5,185 second-parity (28,446 test-day records) cows distributed in 104 herds in the Walloon Region of Belgium. Data of 28,466 SNPs, located on 29 Bos taurus autosomes (BTA), of 1,699 animals (639 males and 1,060 females) were used. Random regression test-day models were used to estimate genetic parameters through the Bayesian Gibbs sampling method. The SNP solutions were estimated using a single-step genomic best linear unbiased prediction approach. The proportion of genetic variance explained by each 25-SNP sliding window (with an average size of ~2 Mb) was calculated, and regions accounting for at least 1.0% of the total additive genetic variance were used to search for candidate genes. Average daily heritability estimated for the included milk FA traits ranged from 0.01 (C4:0) to 0.48 (C12:0) and 0.01 (C4:0) to 0.42 (C12:0) in the first and second parities, respectively. Genetic correlations found between milk yield and the studied individual milk FA, except for C18:0, C18:1 trans, C18:1 cis-9, were positive. The results showed that fat percentage and protein percentage were positively genetically correlated with all studied individual milk FA. Genome-wide association analyses identified 11 genomic regions distributed over 8 chromosomes [BTA1, BTA4, BTA10, BTA14 (4 regions), BTA19, BTA22, BTA24, and BTA26] associated with the studied FA traits, though those found on BTA14 partly overlapped. The genomic regions identified differed between parities and lactation stages. Although these differences in genomic regions detected may be due to the power of quantitative trait locus detection, it also suggests that candidate genes underlie the phenotypic expression of the studied traits may vary between parities and lactation stages. These findings increase our understanding about the genetic background of milk FA and can be used for the future implementation of genomic evaluation to improve milk FA profile in Dual-Purpose Belgian Blue cows.

Legume protein/polysaccharide food hydrogels: Preparation methods, improvement strategies and applications

For the development of innovative foods and nutritional fortification, research into food gel is essential. As two types of rich natural gel material, both legume proteins and polysaccharides have high nutritional value and excellent application potential, attracting wide attention worldwide. Research has focused on combining legume proteins with polysaccharides to form hybrid hydrogels as their combinations show improved texture and water retention compared to single legume protein or single polysaccharide gels, and these properties can be tailored for specific applications. This article reviews hydrogels of common legume proteins and discusses heat induction, pH induction, salt ion induction, and enzyme-induced assembly of legume protein/polysaccharide mixtures. The applications of these hydrogels in fat replacement, satiety enhancement, and delivery of bioactive ingredients are discussed. Challenges for future work are also highlighted.

Evaluation of the impact of hydrogen-rich water on the quality attribute notes of butter

The effects of washing raw butter with hydrogen-rich water (HRW), prepared with hydrogen (H₂) and/or magnesium (Mg), on butter quality were investigated in this research paper. During the washing process, titratable acidity (TA) decreased by 12% for all washed samples. During the storage period, TA increased by 28% and 93% (control), 14% and 58% (H₂), and 10% and 66% (Mg) for the 60^th and 90^th days, respectively. Peroxide value (mEq O₂/kg) increased to 2.76 and 8.83 (control), 1.92 and 7.25 (H₂), and 2.02 and 8.12 (Mg) for the 60^th and 90^th days. HRW samples showed the lowest acid degree value (ADV) and the highest color notes (L*, C*, and h). The HRW treatment of raw butter has shown improving effects on the product without any harmful residuals in the final product or the environment.

Development of Phytocosmeceutical Microemulgel Containing Flaxseed Extract and Its In Vitro and In Vivo Characterization

Antioxidants from natural sources are extensively attaining consideration to avert the skin from damage and aging caused by free radicals. Flaxseed (Linum usitatissimum L.), a natural therapeutic agent, was meant to be explored cosmeceutical by quantifying its potential phytoconstituents and to be incorporated into a microemulgel for topical use. Hydroalcoholic fractions (both methanolic and ethanolic; 80%) flaxseed extracts were subjected to phytochemical screening by quantifying total phenolic content (TPC), total flavonoid content (TFC), and high-performance liquid chromatography-ultraviolet (HPLC-UV), and for biological activities through 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, tyrosinase inhibition assay, and sun protection factor (SPF). Ethanolic fraction was selected for further study by TPC (18.75 mg gallic acid equivalent/g) and TFC (1.34 mg quercetin equivalent/g). HPLC-UV analysis showed the existence of benzoic, quercetin, caffeic, vanillic, p-coumaric, gallic, cinnamic, syringic, and sinapic acids. Biological activities showed 87.00%, 72.00%, and 21.75 values for DPPH assay, tyrosinase inhibition, and SPF assays, respectively. An oil-in-water (OW) microemulsion containing the flaxseed extract, with 99.20 nm Zeta size, −19.3 Zeta potential and 0.434 polydispersity index was developed and incorporated in Carbopol-940 gel matrix to formulate an active microemulgel with 59.15% release in in vitro studies. The successfully formulated stable active microemulgel produced statistically significant effects (p < 0.05), in comparison to a placebo, on skin erythema, melanin, sebum, moisture, and elasticity, in a noninvasive in vivo study performed on 13 healthy human female volunteers. Other cosmeceutical products can also be formulated from flaxseed, making it a considerable candidate for further utilization in the pharmaceutical industry.

Lacticaseibacillus paracasei as a Modulator of Fatty Acid Compositions and Vitamin D3 in Cream

Butter is an important source of essential fatty acids, lipid-soluble vitamins, and antioxidants in the diet. However, this study showed that the presence of the Lacticaseibacillus paracasei strain has a great influence on the fatty acid profile as well as provitamin D3 and vitamin D3 content in the cream—the raw material from which the butter is obtained. The addition of this lactic acid bacteria enriches the cream in 9-hexadecenoic acid, oleic acid, octadeca-9,12-dienoic acid, and conjugated linoleic acid, which exhibit antimutagenic and anticarcinogenic properties. Moreover, a higher level of monounsaturated fatty acids can extend the shelf life of butter in the future. In the present work, we observed that the presence of lactic acid bacteria contributed to an increase in the level of provitamin D after 6 h of incubation and an increase in the levels of vitamin D3 after 24 and 48 h. Fatty acid profiles and the content of vitamins were largely dependent on the presence of light and mixing, which are probably associated with the status of lipid peroxidation.

Effect of microcapsules of chia oil on Ω-3 fatty acids, antioxidant characteristics and oxidative stability of butter

Background

Ω-3 fatty acids perform several therapeutic functions in the body, however, their applications are limited due to the inferior oxidative stability. To improve the oxidative stability and release properties of Ω-3 fatty acids, microencapsulation is performed. Butter is a good source of fat-soluble vitamins and antioxidant systems however, it is not a good source of Ω-3 fatty acids. Supplementation of butter with microcapsules of vegetable oils rich in Ω-3 fatty acids is not reported in literature.

Methods

Microcapsules of chia oil (MCO) were prepared using chitosan as encapsulating material by spray drying at lower temperature. Unsalted butter prepared from cultured cream using Lactococcus lactis ssp. Lactis at 21 °C for 16 Hrs. Cream was churned at 12 °C and microcapsules of chia oil were added to the butter during the working stage at four different concentrations i.e. 2, 4, 6 and 8% (T₁, T₂, T₃ and T₄, respectively). Butter without supplementation of MCO were kept as control. Butter samples were stored for 90 days at -10 °C. Butter composition, antioxidant capacity, fatty acid profile, induction period, free fatty acids, peroxide value and sensory evaluation were performed at 0, 45 and 90 days of storage.

Results

Addition of MCO in butter did not have any effect on standards of identity of butter. Microencapsulation had no effect on fatty acid profile of microcapsules of chia oil. Concentration of alpha-linolenic acid (ALA) in control, T₁, T₂, T₃ and T₄ were 0.49, 4.29, 8.41, 13.21 and 17.44%, respectively. Concentration of ALA in fresh and 90 days stored butter samples were 17.44 and 17.11%, respectively. After 90 days of storage, loss of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) were 0.07%, 0.05 and 0.03%, respectively. At 0, 45 and 90 days of storage, 2, 2-Diphenyl-1-picrylhydrazyle (DPPH) free radical scavenging activity of free chia oil was 39.81, 71.22 and 62.18%, respectively. However, microcapsules of chia oil had superior antioxidant activity. DPPH free radical scavenging activity of microcapsules at 0, 45 and 90 days of storage was 36.51, 36.43 and 35.96%, respectively (p > 0.05). Total antioxidant capacity of microcapsules at 0, 45 and 90 days of storage was 70.53, 69.88 and 68.52%, respectively (p > 0.05). It was recorded that induction period of free chia oil and microcapsules was only 2.86 h and 8.55 h. Among the butter samples, control revealed the lowest induction period. While, induction period of experimental samples was not different from each other. Peroxide value and free fatty acids of the butter samples at the end of storage period (90 days) was less than the European Union standards limit (10MeqO₂/kg and 0.2%). Sensory characteristics of experimental samples were similar to the control. MCO can be added in butter to improve its functional value.

Conclusion

Concentration of Ω-3 fatty acids in butter up to 8% can be increased through microcapsules of chia oil with reasonable oxidative stability and no effect on sensory characteristics.

Effect of Feeding Cows with Unsaturated Fatty Acid Sources on Milk Production, Milk Composition, Milk Fatty Acid Profile, and Physicochemical and Sensory Characteristics of Ice Cream

Simple Summary

The objective of this study was to evaluate the effects of supplementation of dairy cows’ diets with different fatty acid (FA) sources on milk production, milk composition, milk fatty acid profile, and physicochemical and sensory characteristics of ice cream. Supplementation (3% dry matter (DM)) of diets with soybean oil (SO) and fish oil (FO) did not have detrimental effects on milk production, milk composition, or ice cream physicochemical and sensory characteristics. From a human standpoint, SO and FO improved the FA profile of milk.

Abstract

The objective of this study was to evaluate the effects of supplementation of dairy cows with different fatty acid sources (soybean oil (SO) and fish oil (FO)) on milk production, milk composition, milk fatty acid profile, and physicochemical and sensory characteristics of ice cream. During 63 days, fifteen Holstein cows averaging 198 ± 35 days in milk were assigned to three groups: control diet with no added lipid (n = 5 cows); and supplemented diets with SO (n = 5 cows; unrefined SO; 30 g/kg DM) or FO (n = 5 cows; FO from unrefined salmon oil; 30 g/kg DM). Milk production, milk fat, and milk protein were not affected by treatments. Saturated fatty acids in milk fat were decreased with SO and FO compared with control. C18:2 cis-9, cis-12 was increased with SO whereas C18:2 cis-9, trans-11, C20:3n-3, C20:3n-6, C20:5n-3, and C22:6n-3 were the highest with FO. Draw temperature and firmness were higher in SO compared to control and FO ice creams. Melting resistance was higher in FO compared with control and SO ice creams. Supplementation of cow diets with SO and FO did not have detrimental effects on milk production, or ice cream physicochemical and sensory characteristics.

Volatile Organic Compound and Fatty Acid Profile of Milk from Cows and Buffaloes Fed Mycorrhizal or Nonmycorrhizal Ensiled Forage

Seed inoculation of forage crops by arbuscular mycorrhizal fungi (AMF) generally results in higher profitability, but also modifies the chemical composition of silage in terms of increased biomass, protein, and dry matter. Raw milk aroma is affected by the type of feed. This work investigated the influence of ensiled forage obtained by seed inoculation with AMF on the volatile fractions and fatty acid composition of milk. Two experiments were carried out: in the first, buffaloes were fed maize silage, and in the second, cows were fed sorghum silage. The volatile fractions of milk were quantified by headspace solid-phase micro-extraction (HS-SPME), combined with gas chromatography-mass spectrometry (GC-MS), and fatty acids by gas chromatography (GC). The ensiled forage obtained with AMF increased saturated fatty acids (SFAs), and decreased monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) in both experiments. The volatile fraction in milk samples obtained from bovines fed mycorrhizal ensiled forage showed an increase of free fatty acids and ketones, responsible for cheesy and fruity odors. Aldehydes, responsible for green and grassy notes, increased only in the milk from buffaloes fed ensiled maize. Our results suggest that inoculation of maize and sorghum seed with AMF, combined with a low rate of fertilizers, leads to ensiled forage that could slightly affect the FA profile and odor quality of milk.

Impact of vitamin E and selenium on antioxidant capacity and lipid oxidation of cheddar cheese in accelerated ripening

Background

Ripening of cheddar cheese is a time taking process, duration of the ripening may be as long as one year. Long ripening time is a big hindrance in the popularity of cheese in developing countries. Further, energy resources in these countries are either insufficient or very expensive. Therefore, those methods of cheese ripening should be discovered which can significantly reduce the ripening time without compromising the quality characteristics of cheddar cheese. In accelerated ripening, cheese is usually ripened at higher temperature than traditional ripening temperatures. Ripening of cheddar cheese at high temperature with the addition of vitamin E and selenium is not previously studied. This investigation aimed to study the antioxidant activity of selenium and vitamin E in accelerated ripening using cheddar cheese as an oxidation substrate.

Methods

The ripening of cheddar cheese was performed at 18 °C and to prevent lipid oxidation, vitamin E and selenium were used alone and in combination. The treatments were as: cheddar cheese without any addition of vitamin E and selenium (T1), cheddar cheese added with 100 mg/kg vitamin E (T₂), 200 mg/kg vitamin E (T₃), 800 μg/kg selenium (T₄), 1200 μg/kg selenium (T₅), vitamin E 100 mg/kg + 800 μg/kg selenium (T₆) and vitamin E 200 mg/kg + 1200 μg/kg selenium (T₇). Traditional cheddar cheese ripne ripened at 4-6 °C for 9 months was used as positive control. Cheese samples were ripened at 18 °C for a period of 12 weeks and analyzed for chemical and oxidative stability characteristics at 0, 6 and 12 weeks of storage. All these treatments were compared with a cheddar cheese without vitamin E, selenium and ripened at 4 °C or 12 weeks. Vacuum packaged cheddar cheese was ripened 18 °C for a period of 12 weeks and analyzed for chemical and oxidative stability characteristics at 0, 4 and 8 weeks of storage period.

Results

Addition of Vitamin E and selenium did not have any effect on moisture, fat and protein content of cheddar cheese. After 6 weeks of ripening, total antioxidant capacity of T₁, T₂, T₃, T₄, T₅, T₆, T₇ and standard cheese were 29.61%, 44.7%, 53.6%, 42.5%, 41.4%, 64.1%, 85.1% and 25.4%. After 6 weeks of ripening, reducing power of T₁, T₂, T₃, T₄, T₅, T₆, T₇ and SC cheese were 14.7%, 18.1%, 26.3%, 19.2%, 25.3%, 33.4%, 40.3% and 11.6%. After 6 weeks of ripening, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of T₆ and T₇ were 54.2% and 66.9%. While, DPPH free radical scavenging activity of T₁ and standard cheese after 6 weeks of ripening were, 19.1 and 18.5%, respectively. Free fatty acids of vitamin E and selenium supplemented, non-supplemented and standard cheese were not significantly influenced from each other in 0, 6 and 12 weeks old cheddar cheese. Peroxide values of T₁, T₂, T₃, T₄, T₅, T₆, T₇ and standard cheese after 6 weeks of accelerated ripening were 1.19, 1.05, 0.88, 1.25, 0.29, 0.25, 0.24 and 0.28 (MeqO₂/kg). After 6 weeks of ripening, anisidine value of T₆ and T₇ were 6.55 and 6.14. Conjugated dienes of T₁, T₂, T₃, T₄, T₅, T₆, T₇ and standard cheese, after 6 weeks of accelerated ripening were 0.61, 0.55, 0.42, 0.77, 0.65, 0.17, 0.15 and 0.19. After 6 weeks of accelerated ripening, concentrations unsaturated fatty acids in T₁, T₂, T₃, T₄, T₅, T₆, T₇ and standard cheese decreased by18.19%, 17.45%, 16.82%, 16.19%, 12.71%, 8.48%, 6.92% and 14.71%. After 12 weeks of accelerated ripening, concentration of unsaturated fatty acids in T₁, T₂, T₃, T₄, T₅, T₆ and T₇ and standard cheese decreased by 26.2%, 21.2%, 18.7%, 14.2%, 10.4%, 4.84%, 1.03% and 6.78%. Cheddar cheese samples added with vitamin E, selenium and their combinations produced more organic acids during the ripening period of 12 weeks. After 6 and 12 weeks of ripening, flavor score of T₆ and T₇ was better than standard ripened cheddar cheese.

Conclusions

After 6 weeks of accelerated ripening, sensory characteristics of T₆ and T₇ were similar to cheddar cheese that was ripened at 4 °C for 9 months. Ripening time of cheddar cheese may be reduced to 6 weeks by elevated temperature (18 °C) using vitamin E and selenium as antioxidants at T₆ and T₇ levels.

Modification of Lipid Profile in Commercial Cow Milk Samples before and after Their Expiration Date: Evaluation of Storage Crucial Parameters and Possible Environmentally Friendly Disposal Alternatives

Milk waste is considered a highly polluting material and its disposal is an economic and environmental problem for the dairy sector. Despite this, it can be turned into a source of nutraceutical products and biodiesel substrate. The objective of this study was to determine the qualitative and quantitative variation of single fatty acids in cow milk samples before expiration date and within 28 days after expiration date in order to monitor how the profile of the lipid fraction is influenced by different physicochemical parameters. It was shown that lipolysis in milk is a process independent of time but dependent on the values of pH and total titratable acidity, while crucial parameters for the lipid oxidation are temperature and time of exposure to atmospheric oxygen. All of these factors are at the basis of the efficacy of milk storage conditions. Moreover, our data demonstrate that milk, several weeks after its expiry date, is a rich source of fatty acids that may be recovered as potential substrates for the formulation of economically viable products and eco-friendly diesel-like fuels.

Omega-3 fatty acids and oxidative stability of ice cream supplemented with olein fraction of chia (Salvia hispanica L.) oil

BACKGROUND

Chia (Salvia hispanica L.) has been regarded as good source of polyunsaturated omega-3 fatty acids with cardiac, hepatic, hypotensive, antiallergic and antidiabetic role. Concentration of omega-3 fatty acids in chia oil can be enhanced by fractionation. Olein/low melting fraction of chia oil has higher concentration of omega-3 fatty acids. Therefore, main objective of current investigation was determination of various concentration effect of olein fraction of chia oil on omega-3 fatty acids, oxidative stability and sensory characteristics of ice cream.

METHODS

Ice cream samples were prepared by partially replacing the milk fat with olein fraction of chia oil at 5, 10, 15 and 20% concentrations (T1, T2, T3 and T4), respectively. Ice cream prepared from 100% milk fat was kept as control. Ice cream samples stored at -18 °C for 60 days were analysed at 0, 30 and 60 days of the storage period. Fatty acid profile, total phenolic contents, total flavonoids, free fatty acids, peroxide value, anisidine value and sensory characteristics of ice cream samples was studied.

RESULTS

Concentration of α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid in T4 was 13.24, 0.58, 0.42 and 0.31%, respectively. Total phenolic contents of control, T1, T2, T3 and T4 were recorded 0.12, 1.65, 3.17, 5.19 and 7.48 mg GAE/mL, respectively. Total flavonoid content of control, T1, T2, T3 and T4 were found 0.08, 0.64, 1.87, 3.16 and 4.29 mg Quercetin Equivalent/mL. 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity of control, T1, T2, T3 and T4 was noted 5.61, 17.43, 36.84, 51.17 and 74.91%, respectively. After 60 days of storage period, the highest peroxide value of 1.84 (MeqO2/kg) was observed in T4, which was much less than allowable limit of 10 (MeqO2/kg). Flavour score was non-significant after 30 days of storage period.

CONCLUSIONS

Supplementation of ice cream with olein fraction of chia oil enhanced the concentration of omega-3 fatty acids and improved the antioxidant perspectives of ice cream. These results suggest that omega-3 fatty acids and antioxidant characteristics of ice cream may be improved with olein fraction of chia oil for discerning consumers.

Promising features of mango (Mangifera indica L.) kernel oil: a review

Mango kernel contains about 15 % good quality edible oil, that is comparable to soybean and cottonseed, which contain about 18-20 % oil. Mango kernel oil (MKO) has lower free fatty acids, carotenoid content and peroxide value, and is usually used without any processing, which is otherwise mandatory for commercial vegetable oils. Palmitic, stearic and oleic acids are the major fatty acids, triglyceride composition and fatty acid profile suggest wide range of trans free options. With 32-36 °C melting point, MKO is solid at room temperature, thus, does not require partial hydrogenation for application in foods. MKO can be used as an alternative of cocoa butter, which is used in chocolates and confectionaries. Total phenolic contents and induction period of MKO is greater than many commercial vegetable oils; thus, it can be used as an alternative of synthetic antioxidants for the preservation of fats and oils. Mangiferin, chlorogenic acid, quercetin and caffeic acid are the major phenolic compounds present in MKO. Functional properties of MKO can be further improved through fractionation, transesterification and interesterification for increased industrial applications.

Intake of butter naturally enriched with cis9,trans11 conjugated linoleic acid reduces systemic inflammatory mediators in healthy young adults

A conjugated linoleic acid (CLA) depletion-repletion study was carried out to investigate the effects of dietary c9,t11 CLA on C-reactive protein, transcription factor NFκB, metalloproteinases 2 and 9, inflammatory mediators (adiponectin, TNFα, IL-2, IL-4, IL-8, IL-10), body composition, and erythrocyte membrane composition in healthy normal-weight human adults. CLA depletion was achieved through an 8-week period of restricted dairy fat intake (depletion phase; CLA intake was 5.2±5.8 mg/day), followed by an 8-week period in which individuals consumed 20 g/day of butter naturally enriched with c9,t11 CLA (repletion phase; CLA intake of 1020±167 mg/day). The participants were 29 healthy adult volunteers (19 women and 10 men, aged 22 to 36 years), with body mass index between 18.0 and 29.9 kg m(-2). Blood samples were collected at baseline and at the end of both depletion and repletion phases. The content of CLA in erythrocytes decreased during CLA-depletion and increased during CLA-repletion. Intake of CLA-enriched butter increased the serum levels of anti-inflammatory IL-10 but reduced transcription factor NFκB in blood and serum levels of TNFα, IL-2, IL-8 and inactive metalloproteinase-9. Moreover, reduced activity of metalloproteinases 2 and 9 in serum was observed during the CLA-repletion period. In contrast, intake of CLA-enriched butter had no effects on body composition (DXA analysis) as well as on serum levels of adiponectin, C-reactive protein, and IL-4. Taken together, our results indicate that the intake of a c9,t11 CLA-enriched butter by normal-weight subjects induces beneficial changes in immune modulators associated with sub-clinical inflammation in overweight individuals.

Qualidade nutricional e estabilidade oxidativa de manteigas produzidas do leite de vacas alimentadas com cana-de-açúcar suplementada com óleo de girassol

O objetivo deste estudo foi avaliar o perfil de ácidos graxos (AG), os índices de qualidade nutricional e a estabilidade oxidativa (EO) de manteigas produzidas do leite de vacas alimentadas com dietas à base de cana-de-açúcar contendo níveis crescentes de óleo de girassol (OG): 0 (controle); 1,5; 3,0 e 4,5% da matéria seca (MS). O perfil de AG das manteigas foi analisado por cromatografia gasosa, e a EO foi determinada utilizando-se o equipamento Rancimat®, modelo 743, operado a 120ºC e fluxo de ar de 20L/h. As concentrações dos AG rumênico (CLA cis-9, trans-11), vacênico (C18:1 trans-11) e oleico (C18:1 cis-9) na gordura das manteigas foram aumentadas em 867, 687 e 148%, respectivamente, à medida que se aumentou de 0 para 4,5% o nível de OG na dieta. Por outro lado, as concentrações dos AG saturados de cadeia média foram linearmente reduzidas (P<0,0001) na gordura das manteigas, em razão do incremento de OG nas dietas. Quanto aos índices de qualidade nutricional, houve redução linear (P<0,0001) no índice de aterogenicidade e no de trombogenicidade e aumento da relação entre AG hipo e hipercolesterolêmicos, em resposta ao aumento do nível de OG na dieta. Consistente com o incremento (P<0,0001) nas concentrações totais dos AG mono e poli-insaturados, a EO da gordura das manteigas foi linearmente reduzida (P<0,0001) em razão do incremento de OG nas dietas. Concluiu-se que a suplementação com OG melhorou a qualidade nutricional das manteigas produzidas do leite de vacas Holandês x Gir devido a mudanças positivas no perfil de AG da gordura. Entretanto, tais mudanças na composição dos AG da gordura foram acompanhadas de redução da EO das manteigas, associada à menor vida de prateleira.

Modification of fatty acid profile of cow milk by calcium salts of fatty acids and its use in ice cream

This study was conducted to determine the effect of calcium salts of fatty acids (CSFA) on fatty acid profile of milk of "Sahiwal" cows and suitability of milk with modified fatty acids in the formulation of ice cream. Fatty acid profile of cow milk was modified by feeding CSFA to eighteen randomly stratified "Sahiwal" cows of first and early lactation divided into three groups. CSFA were offered at two different levels i.e. T1 (150 g per cow per day) T2 (300 g per cow per day) both treatments were compared with a control (T0) without any addition of calcium salts of fatty acids. Iso caloric and iso nitrogenous feeds were given to both experimental groups and control. Concentrations of short chain fatty acids in T0, T1 and T2 were 9.85 ± 0.48a, 8.8 ± 0.24b and 7.1 ± 0.37c %, respectively and the concentrations of C18:1 and C18:2 increased (P < 0.05) from 27.6 ± 1.32b % to 31.7 ± 1.68a % and 2.15 ± 0.09b % to 2.79 ± 0.05a %, respectively, at T2 level. Incorporation of milk fat of T1 and T2 (modified fatty acids profile) in ice cream did not have any adverse effect on pH, acidity and compositional attributes of ice cream. Viscosity of T1 was 67.94 ± 3.77a as compared to (T0) control 68.75 ± 2.46a (CP). Firmness of experimental samples and control were almost similar (P > 0.05) overall acceptability score of T2 was 7.1 ± 0.28b out of 9 (total score) which was more than 78 ± 2.92 %. It was concluded that CSFA may be successfully incorporated up to T2 level (300 g per cow per day) into the feed of "Sahiwal" cows to produce milk with higher content of unsaturated fatty acids and it may be used in the formulation of ice cream with acceptable sensory characteristics and increased health benefits.

Effect of feeding fresh forage and marine algae on the fatty acid composition and oxidation of milk and butter

This study evaluated the effects of feeding fresh forage either as pasture plus a concentrate (PAS) or as a silage-based total mixed ration (TMR), combined with either a ruminally inert lipid supplement high in saturated fatty acids (-) or a ruminally protected microalgae containing 22 g of docosahexaenoic acid (DHA)/100 g of fatty acids (+) on the fatty acid (FA) composition and oxidation of milk and butter. For the 8 mid-lactation Holstein cows in this study, milk yield was not significantly affected by treatment, averaging 32.3 ± 1.28 kg/d. Milk fat content was higher for PAS⁻, averaging 5.05 compared with 4.10 ± 0.17% for the mean of other treatments, and was significantly depressed with microalgae supplementation (3.97 vs. 4.69 ± 0.17%). The saturated fatty acid level in the milk of cows fed TMR⁻ was significantly higher than that of the other treatments (66.9 vs. 61.2 g/100 g of FA). The level of monounsaturated FA was lowered by feeding TMR⁻ (27.4 vs. 32.0 g/100 g of FA), whereas levels of polyunsaturated FA were elevated by feeding PAS+ compared with the mean of the other treatments (6.54 vs. 5.07 g/100 g of FA). Feeding the rumen-protected microalgae increased the DHA content of milk more than 4-fold (0.06 to 0.26 g/100g of FA) with the PAS treatment. The conjugated linoleic acid content of milk was highest for PAS+ compared with the other treatments (4.18 vs. 3.41 g/100g of FA). In general, the fatty acid composition of butter followed that of milk. Overall, feeding the TMR supplemented with the rumen-protected microalgae increased the levels of volatile products of oxidation in milk and butter. No effect of forage type or microalgae supplementation was observed on the oxidative stability or antioxidant capacity of milk, although the oxidative stability of butter exposed to UV was reduced with microalgae supplementation, particularly with TMR, as assessed by using the ferric reducing ability of plasma assay.

Butter composition and texture from cows with different milk fatty acid compositions fed fish oil or roasted soybeans

Changing the milk fatty acid composition can improve the nutritional and physical properties of dairy products and their acceptability to consumers. A more healthful milk fatty acid composition can be achieved by altering the cow's diet, for example, by feeding supplemental fish oil (FO) or roasted soybeans (RSB), or by selecting cows with a more unsaturated milk fatty acid composition. We examined whether feeding supplemental FO or RSB to cows that had a more unsaturated milk fatty acid composition acted additively to produce butter with improved fatty acid composition and texture. Using a 3 x 3 Latin square design with 2 replications, we fed diets to multiparous Holstein cows (60 to 200 DIM) chosen for producing either more or less unsaturated milk fatty acid composition (n = 6 for each group) for three 3-wk periods. The control diet contained 3.7% crude fat and the 2 experimental diets contained, on a dry matter basis, 0.8% of additional lipids in the form of 0.9% of FO or 5% of RSB. The milk, collected in the third week of feeding, was used to make butter, which was analyzed for its fatty acid composition and physical properties. Dry matter intake, milk yield, and milk composition were not significantly affected by cow diet or by cow selection. Cows that produced a more unsaturated and healthful milk fat prior to the feeding study, according to a "health-promoting index" [HPI = (sum of % of unsaturated fatty acids)/ (%12:0 + 4 x %14:0 + %16:0)], maintained a higher HPI in their butter during the feeding study than did cows with a low HPI. Milk from cows fed supplemental FO or RSB yielded more unsaturated butters with a higher HPI. This butter also was softer when the cows were fed RSB. Feeding RSB to cows chosen for their high milk HPI yielded the most unsaturated butter with the highest HPI and softest texture. Thus, selecting cows with a more health-promoting milk fatty acid composition and feeding supplemental RSB can be used in combination to produce butter that has a consumer-friendly texture and a healthful fatty acid profile.

Major Advances in Concentrated and Dry Milk Products, Cheese, and Milk Fat-Based Spreads

Advances in dairy foods and dairy foods processing since 1981 have influenced consumers and processors of dairy products. Consumer benefits include dairy products with enhanced nutrition and product functionality for specific applications. Processors convert raw milk to finished product with improved efficiencies and have developed processing technologies to improve traditional products and to introduce new products for expanding the dairy foods market. Membrane processing evolved from a laboratory technique to a major industrial process for milk and whey processing. Ultra-filtration and reverse osmosis have been used extensively in fractionation of milk and whey components. Advances in cheese manufacturing methods have included mechanization of the making process. Membrane processing has allowed uniform composition of the cheese milk and starter cultures have become more predictable. Cheese vats have become larger and enclosed as well as computer controlled. Researchers have learned to control many of the functional properties of cheese by understanding the role of fat and calcium distribution, as bound or unbound, in the cheese matrix. Processed cheese (cheese, foods, spreads, and products) maintain their importance in the industry as many product types can be produced to meet market needs and provide stable products for an extended shelf life. Cheese delivers concentrated nutrients of milk and bio-active peptides to consumers. The technologies for the production of concentrated and dried milk and whey products have not changed greatly in the last 25 yr. The size and efficiencies of the equipment have increased. Use of reverse osmosis in place of vacuum condensing has been proposed. Modifying the fatty acid composition of milkfat to alter the nutritional and functional properties of dairy spread has been a focus of research in the last 2 decades. Conjugated linoleic acid, which can be increased in milkfat by alteration of the cow's diet, has been reported to have anticancer, anti-atherogenic, antidiabetic, and antiobesity effects for human health. Separating milk fat into fractions has been accomplished to provide specific fractions to improve butter spreadability, modulate chocolate meltability, and provide texture for low-fat cheeses.

Factors affecting conjugated linoleic acid content in milk and meat

Conjugated linoleic acid (CLA) has been recently studied mainly because of its potential in protecting against cancer, atherogenesis, and diabetes. Conjugated linoleic acid (CLA) is a collective term for a series of conjugated dienoic positional and geometrical isomers of linoleic acid, which are found in relative abundance in milk and tissue fat of ruminants compared with other foods. The cis-9, trans-11 isomer is the principle dietary form of CLA found in ruminant products and is produced by partial ruminal biohydrogenation of linoleic acid or by endogenous synthesis in the tissues themselves. The CLA content in milk and meat is affected by several factors, such as animal's breed, age, diet, and management factors related to feed supplements affecting the diet. Conjugated linoleic acid in milk or meat has been shown to be a stable compound under normal cooking and storage conditions. Total CLA content in milk or dairy products ranges from 0.34 to 1.07% of total fat. Total CLA content in raw or processed beef ranges from 0.12 to 0.68% of total fat. It is currently estimated that the average adult consumes only one third to one half of the amount of CLA that has been shown to reduce cancer in animal studies. For this reason, increasing the CLA contents of milk and meat has the potential to raise the nutritive and therapeutic values of dairy products and meat.

Flavor and stability of pasteurized milk with elevated levels of conjugated linoleic acid and vaccenic acid

The objectives of this study were to determine if flavor differences between 2% fat pasteurized milks with and without naturally enhanced vaccenic acid (VA) and cis-9, trans-11 conjugated linoleic acids (CLA) levels could be detected over the commercial shelf life of the product and to determine if milk with elevated VA and cis-9, trans-11 CLA levels was more susceptible to development of light-induced oxidative flavor defects. Cows were fed a control diet or the same ration supplemented with 2% soybean oil and 1% fish oil (CLA diet). The milk, standardized to 2% fat, was pasteurized, homogenized, and stored in plastic containers at 4 degrees C. Oxidation was induced by exposing half of the containers to light. Testing was conducted at 1, 7, and 14 d postpasteurization. Average cis-9, trans-11 CLA content of the milks from the control and CLA diet groups was 0.52 and 4.74 g/100 g of fatty acids, respectively (8-fold increase). Average VA content of the milk from the control and CLA diet groups was 1.43 and 12.06 g/100 g of fatty acids, respectively (7.5-fold increase). Together, VA plus CLA represented almost 17% of the total milk fatty acids. There was no effect of light exposure on fatty acid composition initially or over the 14-d storage period. Although VA, cis-9, trans-11 CLA, and degree of unsaturation were significantly elevated in the milk from the CLA diet group, untrained panelists were unable to detect flavor differences initially or over time in 15 of 16 triangle test evaluations. Similarly, sensory results indicated no difference in susceptibility to the development of oxidized off-flavors between the milk from the control and CLA diet groups, even when oxidation was induced by light exposure.

Advances in pasture management for animal productivity and health

A wide range of management techniques is available to enhance quantity and quality of forage supply to grazing animals throughout the annual production cycle. Within broad limits, dry matter (DM) production is relatively insensitive to management of defoliation frequency, severity and duration. However defoliation management has effects on feed quality which can be enhanced, in particular, by control of pasture growth in the spring through maintenance of relatively low average pasture masses. Treading damage can have significant immediate and ongoing effects on pasture production and farmers can use a range of management techniques to minimise these. Fertiliser application practices have a potent influence on pasture production and seasonality of that production. Available soil nitrogen is the primary nutrient deficiency limiting production in New Zealand's characteristically grass-dominant pastures. Nitrogen fertiliser usage has increased markedly in recent years, particularly to grow substantially greater amounts of forage during the cool season, and this trend looks set to continue. However, the use of nitrogen fertiliser has important environmental implications. Pasture renewal and forage crop use has also increased in recent years. Care needs to be taken in conducting cost-benefit analyses, selecting the options that best meet the needs, and in establishment and subsequent management practices. Ryegrass (perennial and hybrids) and white clover remain the primary choice for permanent pasture renewal, the availability of safe endophytes having largely alleviated effects of endophyte toxicosis. Special-purpose mixtures are used, especially in dry environments. Italian ryegrasses, brassicas and chicory are common choices for forage crops. A range of management techniques can be used to alleviate deleterious effects of some forages, including ryegrass endophyte toxicosis, facial eczema, and toxins associated with Fusarium fungi. Generally these techniques are not totally effective. More research is required to increase our understanding of these disorders, and in order to develop more effective and reliable management practices.

Modifying milk fat composition of dairy cows to enhance fatty acids beneficial to human health

There is increased consumer awareness that foods contain microcomponents that may have beneficial effects on health maintenance and disease prevention. In milk fat these functional food components include EPA, DHA, and CLA. The opportunity to enhance the content of these FA in milk has improved as a result of recent advances that have better defined the interrelationships between rumen fermentation, lipid metabolism, and milk fat synthesis. Dietary lipids undergo extensive hydrolysis and biohydrogenation in the rumen. Milk fat is predominantly TG, and de novo FA synthesis and the uptake of circulating FA contribute nearly equal amounts (molar basis) to the FA in milk fat. Transfer of dietary EPA and DHA to milk fat is very low (<4%); this is, to a large extent, related to their extensive biohydrogenation in the rumen, and also partly due to the fact that they are not transported in the plasma lipid fractions that serve as major mammary sources of FA uptake (TG and nonesterified FA). Milk contains over 20 isomers of CLA but the predominant one is cis-9,trans-11 (75-90% of total CLA). Biomedical studies with animal models have shown that this isomer has anticarcinogenic and anti-atherogenic activities. cis-9,trans-11-CLA is produced as an intermediate in the rumen biohydrogenation of linoleic acid but not of linolenic acid. However, it is only a transient intermediate, and the major source of milk fat CLA is from endogenous synthesis. Vaccenic acid, produced as a rumen biohydrogenation intermediate from both linoleic acid and linolenic acid, is the substrate, and delta9-desaturase in the mammary gland and other tissues catalyzes the reaction. Diet can markedly affect milk fat CLA content, and there are also substantial differences among individual cows. Thus, strategies to enhance milk fat CLA involve increasing rumen outflow of vaccenic acid and increasing delta9-desaturase activity, and through these, several-fold increases in the content of CLA in milk fat can be routinely achieved. Overall, concentrations of CLA, and to a lesser extent EPA and DHA, can be significantly enhanced through the use of diet formulation and nutritional management of dairy cows.

Texture of butter from cows with different milk fatty acid compositions

Milk fatty acid composition and textural properties of butter are known to be affected by the cows' diets. We examined the phenotypic variation in milk fatty acid composition among cows fed the same diet to see if the variation was sufficient to produce butter with different textural properties. Ten cows were selected that tested higher (n = 5) or lower (n = 5) in their proportion of milk unsaturated fatty acids. Milk samples were collected a week after testing, and butter was prepared from the individual samples. Milk and butter samples were again analyzed for fatty acid composition. Butter at 5 degrees C was evaluated by a sensory panel for spreadability and by a texture analyzer at both 5 and 23 degrees C for hardness and adhesiveness. Milk and butter samples from cows with a more unsaturated milk fatty acid composition had a lower atherogenic index, and the butter samples were more spreadable, softer, and less adhesive. Thus, phenotypic variation in milk fatty acid composition among cows fed the same diet is sufficient to produce butter with different textural properties.