scholarly journals Influence of enzymes with different activity on dynamics of buffalo milk coagulation parameters

2020 ◽  
Vol 12 (3) ◽  
pp. 282-287
Author(s):  
Y. Karacheviev ◽  
V. Galabov ◽  
Т. Аngelova ◽  
D. Yordanova ◽  
V. Karabashev

Abstract: The aim of the present study was to evaluate the effect of 5 species of chymosin with different concentrations on the dynamics of the traits measured by mechanical lactodynamograph, characterizing the coagulation ability of buffalo milk. The coagulation properties of buffalo milk were evaluated on 420 milk samples taken during morning milking from whole milk. Five enzymes (MAXIREN 600, FROMASE 750, MAHIREN XDS, MAXIREN 180 and MAXIREN PREM P) were tested with 4 concentrations each and one control group with a standard, recommended by the manufacturer of the biosensor – mechanical lactodynamometer chymosin (Polo Trade – Computerized Renneting Meter, Italy). The effect of the concentration of each enzyme was determined by examining 20 milk samples. The use of enzymes at various concentrations resulted in substantial variation in the magnitude and direction of changes. Different chymosins with different concentrations actively affect the curd firmness. The shorter coagulation time will provide sufficient time for the curd firming time and its curd firmness. Over 50% of milk samples coagulate by 6 minutes. The effects of enzymes and their different concentrations on measurement were in different groups, which in our opinion was a good prerequisite for using the obtained data for modelling of the measurement process.

2008 ◽  
Vol 16 (3) ◽  
pp. 222 ◽  
Author(s):  
I. JÕUDU ◽  
M. HENNO ◽  
S. VÄRV

The genetic variation of ás1-, â- and ê-caseins and b-lactoglobulin was determined and their effects on the rennet coagulation properties were examined using 335 milk samples from 118 Estonian Native (EN) cows. We found 16 aggregate casein genotypes (ás1-, â-, ê-caseins), of which four . namely, BB A2A2 AA (21.2%), BB A1A2 AB (16.9%), BB A1A2 AA (14.4%), and BB A2A2 AB (10.2%) – occurred among nearly two-thirds of the analysed cows. Aggregate casein genotype had a significant overall effect on rennet coagulation parameters. Better rennet coagulation properties were found for aggregate casein genotypes CC A2A2 AB and BC A1A2 BB, among frequent genotypes for BB A1A2 AB. Of the cattle breeds raised in Estonia, milk from EN had the best coagulation properties and highest frequency of favourable ê-Cn B allele.;


2016 ◽  
Vol 83 (2) ◽  
pp. 242-248 ◽  
Author(s):  
Mauro Penasa ◽  
Valentina Toffanin ◽  
Nicola Cologna ◽  
Martino Cassandro ◽  
Massimo De Marchi

The objective of the present study was to investigate the effect of environmental factors, milk casein content and titratable acidity on milk coagulation properties (MCP) of samples routinely collected in the Trento province (northeast Italy) under field conditions. Rennet coagulation time (RCT, min), curd-firming time (k20, min) and curd firmness (a30, mm) were determined by Formagraph on 14 971 samples from 635 herds associated to 17 dairy factories. Besides MCP, fat, protein, and casein percentages, titratable acidity (TA), and somatic cell and bacterial counts were available. A standardised index of milk aptitude to coagulate (IAC) was derived using information of RCT and a30. An analysis of variance was conducted on MCP and IAC using a fixed effects linear model. Approximately 3% of milk samples did not form a curd within the testing time (30 min) and k20 was missing for 26% of milks. The percentage of samples without information on k20 largely differed among dairy factories (1·7–20·9%). Significant differences were estimated between the best and the worst dairy factory for RCT (−2 min), k20 (−1·2 min), a30 (+3·4 mm) and IAC (+2·6 points). Milk casein content and TA were important factors in explaining the variation of MCP and IAC, supporting the central role of these two traits on technological properties. The Trento province is heterogeneous in terms of dairy systems and this could explain the differences among dairy factories.


2004 ◽  
Vol 10 (6) ◽  
pp. 415-420 ◽  
Author(s):  
L. M. Negri ◽  
M. S. Chavez ◽  
M. A. Taverna ◽  
A. L. Cuatrin ◽  
A. C. Rubiolo

The aim of this work was to study silo raw milk (SRM) compositional parameters that affect the heat stability of whole milk powder (WMP). Seasonal changes of heat stability from SRM and WMP were also characterised. Silo raw milk samples and the corresponding WMP samples were collected twice a month from a local factory from April 2000 to April 2001. Silo raw milk heat coagulation time (HCT), urea and lactose concentrations were found to contribute to milk powder HCT statistical model (R2 = 0.72). High HCT values during summer and low ones during spring were detected for both SRM and WMP samples. Heat coagulation time values of SRM were always higher than those measured in their powders, due to the effects of processing conditions on heat stability


2021 ◽  
pp. 1-10
Author(s):  
H. Thukral ◽  
P. Dhaka ◽  
J. Singh Bedi ◽  
R. Singh Aulakh

Aflatoxin M1 (AFM1) contamination in milk and milk products may pose a major public health concern. The present cross-sectional study was aimed to estimate the prevalence of AFM1 in bovine milk across all districts of Punjab, India and to identify the associated animal and farm level risk factors. A total of 402 milk samples (266 cow milk and 136 buffalo milk) were analysed using commercial ELISA and representative samples were confirmed using HPLC-FLD. The results revealed that 56.2 and 13.4% of the milk samples exceeded the maximum levels of the European Union, i.e. 0.05 μg/l and Food Safety and Standards Authority of India (FSSAI), i.e. 0.5 μg/l for AFM1 in milk, respectively. On analysis of species variation, buffalo milk (prevalence: 56.6%; mean concentration: 0.42±0.9 μg/l) was found to have higher AFM1 levels than cow milk (prevalence: 56.0%; mean concentration: 0.19±0.3 μg/l), with statistically significant difference between mean concentrations (P<0.01) and non-significant difference between AFM1 prevalence (P=0.91). Furthermore, milk from commercial dairy farms (prevalence: 64.7%; mean concentration: 0.34±0.65 μg/l) was found to be more contaminated than from household dairy establishments (prevalence: 47.8%; mean concentration: 0.19±0.65 μg/l). The risk factors ‘above average milk yield/day’ (odds ratio (OR): 2.4) and ‘poor animal hygiene’ (OR: 1.9) were identified at animal level, and ‘intensive dairy farming’ (OR: 3.1) and ‘animal feed without aflatoxin binder’ (OR: 4.7) as farm level risk factors for AFM1 excretion above maximum levels of European Union in milk. Among cow breeds, the milk from ‘non-descript’ breed (OR: 11.5) was found to be most contaminated with AFM1 and the least from Jersey breed (OR: 1.0). The present study highlighted the presence of AFM1 in milk samples; therefore, regular monitoring of AFM1 in milk is required so that high risk regions and associated risk factors can be addressed appropriately.


2004 ◽  
Vol 20 (1-2) ◽  
pp. 109-118 ◽  
Author(s):  
Ognjen Macej ◽  
Snezana Jovanovic ◽  
Miroljub Barac

In this paper, influence of the composition of autohtonous Sjenica cheese and composition of cheese made from cow milk in the type of Sjenica cheese were comparatively investigated. Autohtonous Sjenica cheese, made from ewe's milk and Sjenica type cheese made from cow's milk both had high content of moisture (53.46% and 59.56% respectively), which is the result of production process (coagulation time, curd processing, drying and salting). According to moisture content in fat free basis - MFFB (73.51% and 73.38% respectively) both cheeses belong to soft cheeses group, and according to fat in total solids - FTS (58.66% and 46.75% respectively) they belong to a group of whole milk cheeses. Ripening coefficient of Sjenica cheese made from ewe's milk (21.42%) was larger than ripening coefficient of Sjenica type cheese made from cow's milk (20.41%). Big differences in chemical composition of both cheeses are due to non-uniformly technology, which imposes need to assimilate technology process of Sjenica cheese production and fulfill geographic origin protection of Sjenica cheese as autohthonous cheese characteristic for wider area of Sjenicko-pesterska plateau.


1956 ◽  
Vol 34 (1) ◽  
pp. 689-712 ◽  
Author(s):  
C. G. Drake ◽  
J. J. Seguin ◽  
G. W. Stavraky

The effects of removal of one motor cortex, a frontal lobe, or a complete cerebral hemisphere on the action of various convulsant agents were studied in chronic cats and in spinal preparations. In both sets of experiments, previously decentralized neurons responded to smaller quantities of convulsant drugs than did the intact ones, and pentylenetetrazol, camphor, and picrotoxin, as well as strychnine and acetylcholine, evoked greater and more prolonged responses from these neurons when sufficient time was allowed for sensitization due to partial isolation to take place (in the majority of experiments two to eight months).This was ascertained in myographic recordings and in studies of the electrical activity of the anterior horn cells in high spinal cats and white rats, as well as in photographic and statistical analyses of convulsions induced in chronic animals. The latter study revealed that the convulsions were asymmetrical in the operated cats, the muscular contractions being exaggerated and prolonged contralaterally to the cerebral ablation. The median convulsant dose (CD50) of pentylenetetrazol for the control cats was 7.8 mgm./kgm. (95% confidence limits 7.4–8.1) while that for the operated group was 6.8 mgm./kgm. (95% confidence limits 6.3–7.2). The latent period following the injection of pentylenetetrazol was significantly shorter for the operated group than for the control one, and the convulsions lasted longer in the operated cats than in intact animals. The longer duration of convulsions in the operated group depended on a significantly longer tonic and terminal clonic phase of the convulsion. Two patterns of convulsions could be elicited—a clonic and a more severe clonic–tonic–clonic (CTC) one. In the control group clonic convulsions were more frequent at low dosages of pentylenetetrazol while CTC convulsions pre-dominated at high dosages. In the operated group CTC convulsions were prevalent throughout the range of doses used and occurred in a greater percentage of animals than in the control group. Chemically induced convulsions play a prominent part in the study of epilepsy and in the treatment of some mental derangements, and it is felt that this investigation may contribute to the understanding of the mechanism of action of convulsant agents on the nervous system in which abnormal conditions prevail.


1980 ◽  
Vol 43 (5) ◽  
pp. 376-380 ◽  
Author(s):  
R. S. SINGH ◽  
B. RANGANATHAN

Three Escherichia coli cultures (0111:B4, 0127:B8 and NP) were selected to study their heat-resistant characteristics when in cow skim, cow whole and buffalo whole milk. The temperatures of heat-treatment included in this study were 50, 55, 60 and 63 C. The time interval during heat-treatment was 10 min at 50 and 55 C and 5 min at 60 and 63 C. Marked differences in heat-resistance were observed in the three E. coli cultures. The z-values obtained for strain 0111:B4 were 8.3, 9.0 and 10.2 when tested in cow skim milk, cow whole milk and buffalo milk, respectively. The z-values for 0127:B8 and NP were 17.5, 18.0 and 19.2 and 18.8, 19.0 and 20.3, respectively, for the three types of milk.


1984 ◽  
Vol 47 (9) ◽  
pp. 690-693 ◽  
Author(s):  
C. W. DILL ◽  
C. T. CHEN ◽  
E. S. ALFORD ◽  
R. L. EDWARDS ◽  
R. L. RICHTER ◽  
...  

Lipolysis was quantitated during storage of fluid and freezedried human whole and skim milks. Fatty acid accumulation was faster in whole fluid milk stored for 1 week at 4°C than in frozen (−20°C) samples stored for 180 d. The rapid accumulation of fatty acids during 24 h of storage at 4°C was enhanced in previously frozen milk samples. While freeze-dried whole milk showed no lipolysis when stored at −20°C, accumulation of free fatty acids was rapid in samples stored at room temperature. Fluid and freeze-dried skim milk samples exhibited no appreciable lipolysis.


Molecules ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 177 ◽  
Author(s):  
Changqin Li ◽  
Miyun Hu ◽  
Shengjun Jiang ◽  
Zhenhua Liang ◽  
Jinmei Wang ◽  
...  

Astragalin, isolated from flowers of Rosa chinensis Jacq., is a kind of flavonoid, with anti-inflammatory, antioxidant, antiviral, analgesic, antibacterial, antiallergic, and antihepatotoxic effects. However, no studieson the procoagulant effect of astragalin have been reported. This study aimed to investigate the procoagulant activity of astragalin and its mechanism. Its procoagulant effect was investigated by activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time (PT), and fibrinogen (FIB) in vitro, and a rat model established by heparin sodium was used to evaluate the mechanism for the procoagulant effect in vivo. The results showed that astragalin had good procoagulant effects compared with the control group in vitro. Compared with the model group in vivo, astragalin could shorten the coagulation time and significantly increase the number of platelets. Meanwhile, astragalin could significantly reduce the effectual time of PT and APTT and increase the content of FIB. The contents of 6-keto-PGF1α and eNOS significantly decreased. Astragalin could increase whole blood viscosity (WBV), plasma viscosity (PV), erythrocyte sedimentation rate (ESR) and packedcell volume (PCV). All of the above revealed that astragalin had good procoagulant effects by promoting the intrinsic and extrinsic coagulation system.


2001 ◽  
Vol 68 (4) ◽  
pp. 579-586 ◽  
Author(s):  
SHIRO KUSHIBIKI ◽  
KOICHI HODATE ◽  
JUNICHI KURISAKI ◽  
HIROYUKI SHINGU ◽  
YASUKO UEDA ◽  
...  

β-Lactoglobulin (β-lg) is the main protein of ruminant milk whey. Although β-lg can bind in vitro to a variety of hydrophobic substrates, mainly retinol and long-chain fatty acids, its physiological function is still unknown. In Exp. 1, we investigated the effect of β-lg on the plasma retinol concentration in preruminant calves. Holstein male calves (n = 20) were fed Holstein whole milk at 40 g/kg body weight (BW) plus vitamin A acetate (500,000 i.u.) with or without β-lg (0·4 g/kg BW). The plasma retinol concentration of 10-d-old calves was greater (P<0·05) in the β-lg-fed group than in the control group during the period from 8 to 12 h and at 24 h after the feeding. The postprandial change of plasma retinol in 40-d-old calves fed milk with β-lg was higher (P<0·05) than that in the control calves only at 12 h after the feeding. In Exp. 2, Holstein male calves (n = 18) were used to investigate the effect of β-lg on plasma triglyceride concentration and fatty acid composition. Calves were fed Holstein whole milk at 40 g/kg BW plus milk fat prepared from whole milk at 2 g/kg BW with or without β-lg (0·4 g/kg BW). Plasma triglyceride concentration at age 10 d was higher (P<0·05) in the β-lg-fed group than in the controls during the periods from 1 to 2 h and from 7 to 11 h after the feeding. At age 40 d, plasma triglyceride in the β-lg-fed group was higher (P<0·05) than in the control group only at 9 h. Ratios of palmitic, stearic, and oleic acids to total plasma lipids were higher (P<0·05) in the calves fed β-lg milk than in the control calves at age 10 d. These results suggest that β-lg enhances the intestinal uptake of retinol, triglyceride, and long-chain fatty acids in preruminant calves.


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