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1.
Lipids Health Dis ; 19(1): 74, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293468

RESUMO

BACKGROUND: In the manufacturing of set yoghurt, after reaching 4.6 pH, post fermentation cooling is applied to stop the bacterial activity. Depending upon the required textural and flavor attributes, one phase and two phase cooling patterns are accordingly selected. In one phase cooling, temperature of the yoghurt is rapidly decreased below 10 °C using blast freezing and then it is gradually dropped to 4-5 °C. In two phase cooling, temperature of yogurt is rapidly decreased to less than 20 °C and then it is gradually decreased to 4-5 °C. These cooling phases have a significant impact on textural and flavor perspectives of yoghurt. It is necessary to study the impact of industrially adopted cooling patterns on fatty acid profile, antioxidant characteristics, lipid oxidation and sensory characteristics of cow and buffalo milk set yoghurt. METHODS: This experiment was organized in a completely randomized design and every treatment was replicated five times to minimize the variation. Whole cow and buffalo milk without any standardization were converted to set yoghurt (400 g cups) using Strepotococcus thermophillus and Lactobacillus bulgaricus as starter bacteria. After reaching 4.6 pH, cow and buffalo yoghurt samples were exposed to three different cooling patterns. In first trial, samples of cow and buffalo yoghurt were cooled from 43 °C to 25 °C in 1 h and finally cooled to 4-5 °C in another hr. (T1). In second trial, samples were cooled from 43 °C to 18 °C in 1 hr. and finally cooled down to 4-5 °C in another 1 h. (T2). In third trial, samples were cooled from 43 °C to 4-5 °C in 2 h (T1). Alteration in fatty acid profile, total antioxidant capacity, reducing power, free fatty acids, peroxide value, conjugated dienes, vitamin A, E, color and flavor of cow and buffalo yoghurt samples were assessed for 20 days at the frequency of 10 days. RESULTS: All the three cooling patterns had a non-significant effect on compositional attributes of yoghurt. Buffalo milk yogurt had higher percentage of fat, protein and total solids than yoghurt prepared from cow milk (p < 0.05). At zero day, DPPH free radical scavenging activity of T2 and T3 was significantly higher than T1. This may be due to the longer exposure of T1 at relatively higher temperature than T2 and T3. Effect of storage period up to 10 days was non-significant in T2 and T3. Reducing power of cow and buffalo milk yoghurt was also significantly affected by the cooling patterns applied. Reducing power of T2 and T3 was considerably higher than T1 (p < 0.05). At zero-day, total antioxidant capacity of cow and buffalo milk yoghurt in T3 was 42.6 and 61.4%, respectively. At zero day, total antioxidant capacity of T2 and T3 was significantly higher than T1. Effect of storage on total antioxidant capacity of T2 and T3 remained non-significant till 10 days of storage. At zero day, the impact of cooling patterns on fatty acid profile of T1, T2 and T3 was non-significant, whereas, storage period had a marked impact on fatty acid profile. After 10 days, T1 was considerably different in fatty acids from T2 and T3. After 10 days of storage of cow milk yoghurt in T1, concentration of C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C16:0, C18:0, C18:1 and C18:2 decreased by 0.1, 0.11, 0.09, 0.07, 0.21, 0.38, 0.28, 0.27, 0.44 and 0.06%, respectively. Cow milk yoghurt in T1 after 10 days of storage, concentration of C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C16:0, C18:0, C18:1 and C18:2 decreased by 0.07, 0.15, 0.04, 0.17, 0.20, 0.34, 0.27, 0.36 and 0.04%, respectively. After 10 days of storage in T2 and T3, loss of fatty acids was 1.2 and 3.61% from C4:0 to C10:0, respectively. Milk type had no effect on peroxide value of yoghurt. Cooling of cow and buffalo yoghurt from 43 °C to 25 °C had a pronounced effect on peroxide value. At zero day, peroxide values of cow and buffalo yoghurt in T1 were 0.32 and 0.33 (MeqO2/kg). At zero day, peroxide value of cow and buffalo yoghurt in T2 were 0.24 and 0.26 (MeqO2/kg). At zero day, peroxide value cow and buffalo yoghurt in T3 were 0.23 and 0.25 (MeqO2/kg). Cooling patterns i.e. from 43 °C to 25, 18 and 5 °C (T1, T2 and T3) had a significant effect on the amount of vitamin A and E. Concentration of vitamin A and E in T1 were significantly less than T2 and T3. Cooling patterns had a significant effect on texture, T1 had a thick texture with higher viscosity as compared to T2 and T3. Thickness of yoghurt was in the order of T1 > T2 > T3 with no difference in color and flavor score till 10 days of storage. CONCLUSION: Results of current investigation indicated that milk type and post fermentation cooling patterns had a pronounced effect on antioxidant characteristics, fatty acid profile, lipid oxidation and textural characteristics of yoghurt. Buffalo milk based yoghurt had more fat, protein, higher antioxidant capacity and vitamin content. Antioxidant and sensory characteristics of T1 were optimum till 10 days of storage.


Assuntos
Temperatura Baixa , Ácidos Graxos/análise , Manipulação de Alimentos , Iogurte/análise , Animais , Búfalos , Bovinos , Ácidos Graxos/química , Fermentação , Peroxidação de Lipídeos , Leite , Oxirredução , Iogurte/microbiologia
2.
Lipids Health Dis ; 18(1): 41, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717735

RESUMO

Milk and dairy products are integral part of human nutrition and they are considered as the carriers of higher biological value proteins, calcium, essential fatty acids, amino acids, fat, water soluble vitamins and several bioactive compounds that are highly significant for several biochemical and physiological functions. In recent years, foods containing natural antioxidants are becoming popular all over the world as antioxidants can neutralize and scavenge the free radicals and their harmful effects, which are continuously produced in the biological body. Uncontrolled free radicals activity can lead to oxidative stresses, which have been implicated in breakdown of vital biochemical compounds such as lipids, protein, DNA which may lead to diabetes, accelerated ageing, carcinogenesis and cardiovascular diseases. Antioxidant capacity of milk and milk products is mainly due to sulfur containing amino acids, such as cysteine, phosphate, vitamins A, E, carotenoids, zinc, selenium, enzyme systems, superoxide dismutase, catalase, glutathione peroxidase, milk oligosaccharides and peptides that are produced during fermentation and cheese ripening. Antioxidant activity of milk and dairy products can be enhanced by phytochemicals supplementation while fermented dairy products have been reported contained higher antioxidant capacity as compared to the non-fermented dairy products. Literature review has shown that milk and dairy products have antioxidant capacity, however, information regarding the antioxidant capacity of milk and dairy products has not been previously compiled. This review briefly describes the nutritional and antioxidant capacity of milk and dairy products.


Assuntos
Antioxidantes/metabolismo , Laticínios , Leite , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Búfalos , Caseínas/metabolismo , Caseínas/farmacologia , Bovinos , Cabras , Humanos , Leite/química , Leite/metabolismo , Valor Nutritivo , Ovinos , Proteínas do Soro do Leite/metabolismo , Proteínas do Soro do Leite/farmacologia
3.
Lipids Health Dis ; 18(1): 59, 2019 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-30851732

RESUMO

BACKGROUND: Among the dietary lipids, milk fat is most complicated as it contains more than one hundred types of fatty acids and several triglycerides. Huge versatility in triglyceride and fatty composition makes it possible to convert milk fat into various fractions on the basis of melting characteristics. Functional properties of milk fat can be increased by converting it into different fractions. After cow milk, buffalo milk is the second largest source of milk and chemical characteristics of buffalo milk fat has been studied in a limited fashion. The main mandate was determination of triglyceride, fatty acid profile and antioxidant characteristics of low melting point fractions of buffalo milk fat for increased industrial applications. METHODS: Buffalo milk fat (cream) was fractionated at three different temperatures i.e. 25, 15 and 10 °C by dry fractionation technique and packaged in 250 ml amber glass bottles and stored at ambient temperature for 90 days. The fraction of milk fat harvested at 25, 15 and 10 °C were declared as LMPF-25, LMPF-15 and LMPF-10. Unmodified milk fat was used as control (PBMF). Low melting point fractions were analyzed for triglyceride composition, fatty acid profile, total phenolic contents, DPPH free radicals scavenging activity, reducing power, free fatty acids, peroxide value, iodine value and conjugated dienes at 0, 45 and 90 days of storage. RESULTS: In LMPF-10, concentrations of C36, C38, C40, and C42 were 2.58, 3.68, 6.49 and 3.85% lower than PBMF. In LMPF-25, concentrations of C44, C46, C48, C50, C52 and C54 were 0.71, 1.15, 2.53, 4.8, 0.39 and 2.39% higher than PBMF. In LMPF-15, concentrations of C44, C46, C48, C50, C52 and C54 were 2.45, 4.2, 3.47, 5.92, 2.38 and 3.16% higher than PBMF. In LMPF-10, concentrations of C44, C46, C48, C50, C52 and C54 were 2.8, 5.6, 5.37, 7.81, 3.81 and 4.45% higher than PBMF. LMPF-25, LMPF-15 and LMPF-10 had higher concentration of unsaturated fatty acids as compared PBMF. Total phenolic contents of buffalo milk fat and its fractions were in the order of LMPF-10 > LMPF-15, LMPF-25 > PBMF. Storage period of 45 days had a non-significant effect on total flavonoid content. 2, 2-Diphenyl-1-picrylhydrazyl free radical scavenging activity (DPPH) free radical scavenging activity of LMP-25, LMPF-15 and LMPF-10 were 4.8, 13.11 and 25.79% higher than PBMF. Reducing power of PBMF, LMPF-25, LMPF-15 and LMPF-10 were 22.81, 28.47, 37.51 and 48.14, respectively. Estimation of free fatty acids after the 90 days of storage duration, no significant difference was found in content of free fatty acids in unmodified milk fat and low melting point fractions. Testing of peroxide value in 90 days old samples showed that peroxide value of PBMF, LMPF-25, LMPF-15 and LMPF-10 was 0.54, 0.98, 1.46 and 2.22 (MeqO2/kg), respectively. Storage period up to 45 days had a non-significant effect on anisidine value, iodine value and conjugated dienes. CONCLUSION: Low melting point fractions of buffalo milk fat had higher concentration of unsaturated fatty acids and more antioxidant capacity than unmodified milk fat with reasonable storage stability.


Assuntos
Antioxidantes/análise , Búfalos , Ácidos Graxos/análise , Leite/química , Triglicerídeos/análise , Animais , Ácidos Graxos/química , Flavonoides/análise , Glicolipídeos/análise , Glicolipídeos/química , Glicoproteínas/análise , Glicoproteínas/química , Gotículas Lipídicas , Fenóis/análise , Temperatura de Transição
4.
Lipids Health Dis ; 17(1): 228, 2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30285870

RESUMO

BACKGROUND: Buffalo milk is the second largest source of milk on the globe, it is highly suitable for the preparation of mozzarella cheese, however, it is not suitable for the preparation of cheddar cheese due to high buffering capacity, low acid development, excessive syneresis, lower lipolysis that lead to lower sensory score. Accelerated ripening can enhance lipolysis and improve sensory characteristics of cheddar cheese. Lipolysis and antioxidant capacity of buffalo cheddar cheese in conventional ripening is not previously studied. Optimization of ripening conditions can lead to better utilization of buffalo milk in cheese industry. METHODS: Effect of accelerated ripening on lipolysis and antioxidant properties of cow and buffalo cheddar cheese were investigated. Cheddar cheese prepared from standardized (3.5% fat) cow and buffalo milk was subjected to conventional and accelerated ripening (4 °C and 12 °C) for a period of 120 days. Fatty acid profile, organic acids, free fatty acids, cholesterol, antioxidant activity and sensory characteristics were studied at 0, 40, 80 and 120 days of ripening. RESULTS: Fatty acid profile of cow and buffalo cheddar in conventional (120 days old) and accelerated ripening were different from each other (p < 0.05). Free fatty acids in 120 days old buffalo and control cheddar, in accelerated ripening were 0.55% and 0.62%. After accelerated ripening, cholesterol in buffalo and control cheddars were 16 and 72 mg/100 g. After accelerated ripening, concentrations of formic, pyruvic, lactic, acetic and citric acids in buffalo cheddar cheese were, 922, 136, 19,200, 468 and 2845 ppm. At the end of accelerated ripening (120 days), concentrations of formic, pyruvic, lactic, acetic and citric acids in cow cheddar cheese were 578, 95, 9600, 347 and 1015 ppm. Total antioxidant capacity of control cow and buffalo cheddar in accelerated ripening was 77.26 and 88.30%. Colour, flavour and texture score of rapid ripened 80 and 120 days old buffalo cheddar was not different from cow cheddar. CONCLUSIONS: Results of this investigations showed that flavour profile buffalo cheddar subjected to accelerate ripening was similar to cow cheddar cheese. Accelerated ripening can be used for better utilization of buffalo milk in cheddar cheese industry.


Assuntos
Antioxidantes/análise , Queijo/análise , Ácidos Graxos/metabolismo , Manipulação de Alimentos/métodos , Animais , Búfalos , Bovinos , Ácidos Graxos/análise , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/metabolismo , Feminino , Lipólise , Leite/química
5.
Lipids Health Dis ; 17(1): 79, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29642933

RESUMO

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.


Assuntos
Antioxidantes/farmacologia , Queijo/análise , Metabolismo dos Lipídeos/efeitos dos fármacos , Selênio/farmacologia , Vitamina E/farmacologia , Compostos de Bifenilo/química , Ácidos Graxos/análise , Sequestradores de Radicais Livres/química , Oxirredução , Peróxidos/análise , Picratos/química
6.
Lipids Health Dis ; 17(1): 190, 2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-30115071

RESUMO

BACKGROUND: In many developing countries, milk chilling facilities are not available on the farm where milk is produced, rather these are located at the distance of 10-12 km. After milking, it takes about 2-3 h to reach milk to the chilling facilities. The milk is then chilled and transported to the milk processing plants for thermal processing and value addition. In developing countries, shelf life of pasteurized milk is only 3 days, as compared to 7-10 days in developed countries. The factors which are responsible for the shorter shelf life of pasteurized milk should be discovered for the improvement of dairy sectors of these countries. The magnitude of chemical changes which takes place in un-chilled milk and their effect on fatty acids profile, antioxidant status and lipid oxidation is not previously studied. METHODS: Raw milk samples of the same farm were either rapidly chilled to 4 °C immediately or held at room temperature (35 ± 2 °C) for 2 h followed by rapid chilling to 4 °C. Immediately and delayed chilled raw milk samples were stored at 4 °C for 72 h. Both milk samples were pasteurized at 65 °C, filled in 250 ml transparent PET bottles and stored at 4 °C for 6 days. Fatty acid profile, selenium, zinc, total antioxidant capacity, total flavonoid content and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, free fatty acids, peroxide value and anisidine value were determined at different stages of the experiment. This experiment was repeated with milk of same farm for at least five times. RESULTS: Storing raw milk at ambient temperature (35 ± 2 °C) significantly influenced the pH and lactose content of milk. The loss of short-chain fatty acids in delayed chilled milk was 1.19%, 3.27% and 1.60%, as compared to immediately chilled raw milk. In delayed chilled milk, loss of C18:1 and C18:2 after 3 days of storage period was 6.67% and 01.22. In delayed chilled milk after 6 days of storage, loss of C18:1 and C18:2 was 7.7% and 1.39%, respectively. In immediately chilled milk loss of C18:1 and C18:2 after 3 days of storage was 3.48% and 0.64%. In immediately chilled milk loss of C18:1 and C18:2 after 6 days of storage was 4.57% and 0.9%. Almost 41% vitamin E was lost when raw milk was stored at ambient temperature for 2 hrs. About 21% and 7% vitamin E was lost in delayed and immediately chilled milk, when samples were analyzed immediately after pasteurization. Loss of selenium and zinc contents after 2 h of ambient storage of raw milk were 0.43 and 224 µg/100 g. After 2 h of storage of milk at ambient temperature, free fatty acids increased by 0.03% (p < 0.05). After 6 days of storage, rise of free fatty acids in immediately and delayed chilled milk was 0.06% and 0.14%, respecitively. Rise of 0.13(MeqO2/kg) was recorded, when un-chilled raw milk was stored at ambient temperature for 2 h. After 3 and 6 days of storage, peroxide value of pasteurized milk (delayed chilled) was 0.88 and 1.56 (MeqO2/kg). After 3 and 6 days of storage, peroxide value of pasteurized (immediately chilled) was 0.39 and 0.42(MeqO2/kg). After 2 hrs of ambient storage, 18.41% flavonoids were lost. After 2 hrs of ambient storage of raw milk, loss of total antioxidant capacity and DPPH free radical scavenging activity was 29.31% and 44.53%. After 6 days of pasteurization, loss of total antioxidant capacity and DPPH free radical scavenging activity in delayed chilled raw milk was 72.1% and 89.57%. CONCLUSIONS: The findings of this investigation showed that delayed chilling of raw milk leads to several undesirable chemical changes in lipid fraction of milk.


Assuntos
Temperatura Baixa , Lipídeos/análise , Lipídeos/química , Leite/química , Pasteurização , Animais , Antioxidantes/análise , Bovinos , Ácidos Graxos/análise , Minerais/análise , Oxirredução , Vitaminas/análise
7.
J Food Sci Technol ; 55(3): 992-1002, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29487441

RESUMO

Effect of mango kernel fat (MKF) on antioxidant characteristics and lipolysis of Gouda cheese was investigated. Milk fat (3.5%) was partially replaced with MKF i.e. 5, 10, 15 and 20% concentrations (T1, T2, T3 and T4). Cheese prepared from 100% milk fat served as control. Cheese samples were ripened for 90 days at 6 ± 1 °C and analysed at 0, 45 and 90 days of ripening. Total phenolic contents of control, T1, T2, T3 and T4 were 14 ± 0.35, 129 ± 0.75, 188 ± 2.52, 267 ± 10.61 and 391 ± 8.46 mg GAE/g. Total flavonoid content of control, T1, T2, T3 and T4 were 0.22 ± 0.03, 1.47 ± 0.09, 3.62 ± 0.15, 5.88 ± 0.35, 8.29 ± 0.63 mg quercetin equivalent/ml. DPPH free radical scavenging activity of control and experimental samples increased throughout the ripening period. DPPH free radicals scavenging activity of 90 days old control, T1, T2, T3 and T4 were 16.38 ± 0.0.26e, 30.47 ± 0.64d, 68.62 ± 0.91c, 73.29 ± 0.85b, 92.61 ± 1.44a %. HPLC characterization revealed the existence of mangiferin, caffeic acid, catechin, quercetin and chlorogenic acid in MKF fortified Gouda cheese. Fortification of MKF increased the concentration of C18:1, C18:2 and C18:3 in cheese. The concentration of C18:1, C18:2 and C18:3 in control were 24.55 ± 0.95, 1.76 ± 0.09 and 0.31 ± 0.02%. While, the concentration of C18:1, C18:2 and C18:3 in T4 were 30.11 ± 1.34, 2.79 ± 2.79 and 0.92 ± 0.11%. MKF fortified Gouda cheese had better oxidative stability and sensory characteristics. These results evidenced that antioxidant capacity, unsaturated fatty acids and oxidative stability of Gouda cheese can be improved with MKF.

8.
Lipids Health Dis ; 16(1): 163, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28836975

RESUMO

BACKGROUND: Antioxidant capacity of milk is largely due to vitamins A, E, carotenoids, zinc, selenium, superoxide dismutase, catalase, glutathione peroxidase and enzyme systems. Cow milk has antioxidant capacity while the antioxidant capacity of buffalo milk has been studied in a limited way. The information regarding the effect of pasteurization and boiling on antioxidant capacity of cow and buffalo milk is also scared. METHODS: Cow and buffalo milk was exposed to two different heat treatments i.e. 65 °C for 30 min and boiling for 1 min. After heat treatments, milk samples were cooled down to 4 °C packaged in transparent 250 ml polyethylene PET bottles and stored at 4 °C for 6 days. Milk composition, total flavonoid content, total antioxidant capacity, reducing power, DPPH free radical scavenging activity, antioxidant activity in linoleic acid, vitamin C, A, E, selenium, Zinc, fatty acid profile, peroxide value and sensory characteristics were studied in raw, pasteurized and boiled cow and buffalo milk at 0, 3 and 6 days of storage period. RESULTS: Total antioxidant capacity (TAC) of raw, pasteurized and boiled milk for cow (42.1, 41.3 and 40.7%) and buffalo (58.4, 57.6 and 56.5%) samples was found, respectively. Reducing power (RP) of raw cow and buffalo milk was 6.74 and 13.7 while pasteurization and boiling did not showed significant effect on RP of both cow and buffalo milk. DPPH activity of raw, pasteurized and boiled milk for cow (24.3, 23.8 and 23.6%) and buffalo (31.8, 31.5 and 30.4%) samples was noted, respectively. Storage period up to 3 days was non-significant while DPPH assay after 6 days of storage period indicated significant decline in antioxidant activity of milk samples. Antioxidant activity in linoleic acid (AALA) of buffalo and cow milk were recorded 11.7 and 17.4%, respectively. Pasteurization and boiling did not showed any impact on antioxidant capacity of cow and buffalo milk. The Loss of vitamin C in pasteurization (40 and 42%) and boiling (82 and 61%) of cow and buffalo milk was recorded, respectively. Concentration of vitamin A and E in pasteurized cow and buffalo milk was not significantly different from raw milk samples of cow and buffalo. Concentration of selenium and zinc was not influenced by the heat treatment in both cow and buffalo milk samples. After 3 days of refrigerated storage, antioxidant capacity of both cow and buffalo milk decreased. Concentrations of short-chain and medium-chain fatty acids increased in pasteurized and boiled cow and buffalo milk, while long-chain fatty acids decreased in pasteurized and boiled cow and buffalo milk, with no effect on colour and flavor score. Peroxide value of pasteurized and boiled cow and buffalo milk was not influenced by the storage up to 3 days. CONCLUSIONS: These results suggest that buffalo milk had a higher antioxidant capacity than cow milk and pasteurized milk should be consumed within 3 days of refrigerated storage for better antioxidant perspectives.


Assuntos
Antioxidantes/química , Ácidos Graxos/química , Leite/química , Animais , Búfalos , Bovinos , Conservação de Alimentos , Temperatura Alta , Ácido Linoleico/química , Pasteurização , Selênio/química , Vitamina A/química , Vitamina E/química , Zinco/química
9.
Vet World ; 12(1): 12-33, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30936650

RESUMO

The current rate of population growth is so fast that, to feed this massive population, a 2-fold increase in land is required for the production of quality food. Improved dietary products such as milk and its products with antioxidant properties and functional foods of animal origin have been utilized to prevent chronic diseases. The designer milk contains low fat and less lactose, more protein, modified level of fatty acids, and desired amino acid profiles. The importance of milk and its products is due to the presence of protein, bioactive peptides, conjugated linoleic acid, omega-3 fatty acid, Vitamin D, selenium, and calcium. These constituents are present in milk product, play a key role in the physiological activities in human bodies, and act as anti-inflammatory, anti-tumor, antioxidant, hypocholesterolemic, immune boosting, and antimicrobial activities. Consumer awareness regarding benefits of designer foods such as milk and its products is almost non-existent worldwide and needs to be established to reach the benefits of designer food technologies in the near future. The main objective of this review was to collect data on the antioxidant properties of milk and its constituents which keep milk-derived products safe and preserved.

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