scholarly journals Whey pretreatments before ultrafiltration

1994 ◽  
Vol 3 (5) ◽  
pp. 473-479
Author(s):  
Tuomo Tupasela ◽  
Heikki Koskinen ◽  
Pirkko Antila
Keyword(s):  
Protein Content ◽  
Dry Matter ◽  
Whey Proteins ◽  
Ph Adjustment ◽  
Total Solids ◽  
Heat Treated ◽  
Protein Membrane ◽  
Membrane Isolation ◽  
Solids Content ◽  
Β Lactoglobulin

Whey is a by-product of cheesemaking. Whey dry matter contains mainly lactose, but also valuable whey proteins. The aim of this study was to develop improvements to whey protein membrane isolation processes. In our trials CaCl2 -added, pH-adjusted and heat-treated wheys were found to have MF (microfiltration) permeate fluxes about 30% higher than in untreated MF whey. The total solids and protein content of the MF permeates decreased compared to the original wheys. UF (ultrafiltration) trials were conducted using MF whey to compare it with centrifugally separated whey. The MF whey consistently maintained an UF flux about 1.5 to 2.5 times higher than that of the separated whey. Differently treated MF whey UF permeate fluxes also showed a difference. With CaCl2 addition, pH adjustment and heat treatment, the UF permeate fluxes were about 20 to 40% higher than when only MF was used. The total solids content decreased in each trial. The protein content of the UF concentrate also decreased compared to the MF permeate. The (β-lg (β-lactoglobulin) and α-la (α-lactalbumin) content was almost the same in UF concentrates as in MF permeates.

scholarly journals The chemical composition and technological properties of milk obtained from the morning and evening milking

2008 ◽  
Vol 56 (5) ◽  
pp. 187-198 ◽  
Author(s):  
Martin Skýpala ◽  
Gustav Chládek
Keyword(s):  
Protein Content ◽  
Milk Yield ◽  
Milk Fat ◽  
Protein Production ◽  
Milk Protein ◽  
Fat Content ◽  
Total Solids ◽  
Milk Protein Content ◽  
Solids Content ◽  
Morning Milk

Milk yield varies during lactation, following what is termed a lactation curve. ŽIŽLAVSKÝ and MIKŠÍK (1988) recorded changes in milk yield within a day, too. TEPLÝ et al. (1979) a KOUŘIMSKÁ et al. (2007) published variation within a day ± 1.10 kg in milk yield, ± 0.75 % in milk fat content and ± 0.20 % in milk protein content. Milk yield of cows can be expressed in many different ways, for instance, in kilograms per lactation or in kilograms per day. A practical parameter describing milk production is milk yield (kg) per milking.The object of experiment were 12 cows of Holstein cattle on the first lactation from the 100-day of lactation to 200-day of lactation. The samples of milk were collected from January to May 2007, once a month from the morning and evening milking (milking interval 12 h ± 15 min.). The following parameters were monitored: milk production – milk yield (kg), milk protein production (kg), milk fat production (kg); milk composition – milk protein content (%), milk fat content (%), lactose content (%), milk solids-not-fat content (%), milk total solids content (%); technological properties of milk – ti­tra­tab­le acidity (SH), active acidity (pH), rennet coagulation time (s), quality of curd (class) and somatic cell count as a parameter of udder health.Highly significant differences were found (P < 0.01) between morning milk yield (15.7 kg) and evening milk yield (13.8 kg), between morning milk protein production (0.51 kg) and evening milk protein production (0.45 kg) and between evening milk fat content (4.41 %) and morning milk fat content (3.95 %). A significant difference (P < 0.05) was found between morning milk total solids content (12.62 %) and evening milk total solids content (12.07 %). No significant differences were found between morning (M) and evening (E) values of the remaining parameters: milk fat production (M 0.62 kg; E 0.60 kg), milk protein content (M 3.24 %; E 3.27 %), milk lactose content (M 4.78 %; E 4.86 %), milk solids-not-fat content (M 7.69 %; E 7.71 %), somatic cell count (M 80 000/1 mL; E 101 000/1 mL), titratable aci­di­ty (M 7.75 SH; E 7.64 SH), active acidity (M pH 6.58; E pH 6.61), rennet coagulation time (M 189 s.; E 191 s.), quality of curd (M 1.60 class; E 1.57 class).

Peculiarities of extraction of β-lactoglobuline in protein mineral concentrates at electroactivation of whey

2020 ◽  
Vol 2 (1) ◽  
pp. 52-68
Author(s):  
Mircea BOLOGA ◽  
Elvira VRABIE ◽  
Irina PALADII ◽  
Olga ILIASENCO ◽  
Tatiana STEPURINA ◽  
...  
Keyword(s):  
Protein Content ◽  
Whey Proteins ◽  
Sodium Dodecyl ◽  
Total Protein Content ◽  
Treatment Regimens ◽  
Sds Page ◽  
Different Types ◽  
Lower Protein ◽  
Β Lactoglobulin ◽  
Excellent Source

Introduction. Whey is a by-product and an excellent source of proteins that is rather aggressive due to a large amount of organic substances it contains. The electro-activation of whey applied in the experiments is a wasteless method that allows the va-lorification of all whey components. β-lactoglobulin (β-Lg) makes up 50% of the whey proteins and 12% of the total protein content in milk. Material and methods. The recovery of β-Lg in protein-mineral concentrates (PMC) by electro-activation processing of different types of whey with different initial protein content was investigated in seven configurations. The recovery of protein fractions in the PMCs were analyzed via electrophoresis with sodium dodecyl sulfate (SDS-PAGE) and 15% non-denaturing polyacrylamide gel (PAAG).      Results. Whey electro-fractionation and the obtaining of PMCs with predetermined protein content, namely of β-Lg, were studied on three whey types, processed at different treatment regimens and in seven configurations. The proper management of electroactivation by varying the treatment regimens will allow the electro-fractionation of different types of dairy by-products. Conclusions. The maximum amount of β-Lg recovered in PMCs on electroactivation is  66-71% depending on the processed whey and on the treatment regimens. Obviously, the extraction of β-Lg from initially lower protein content shows a higher recovery degree of β-Lg. The registered temperatures allows formation of PMCs without thermal denaturation.

Use of Lycopersicon cheesmanii and L. chmielewskii to increase dry matter content of tomato fruit

1993 ◽  
Vol 73 (1) ◽  
pp. 273-279 ◽  
Author(s):  
V. Poysa
Keyword(s):  
Lycopersicon Esculentum ◽  
Dry Matter ◽  
Tomato Fruit ◽  
Fruit Size ◽  
Fruit Yield ◽  
Soluble Solids ◽  
High Yield ◽  
Dry Matter Content ◽  
Total Solids ◽  
Solids Content

Advanced lines and backcrosses from interspecific hybridization of processing tomato (Lycopersicon esculentum Mill.) with six L. chmielewskii (Rick, Kesicki, Fobes and Holle) and L. cheesmanii (Riley) accessions were evaluated in the field over 2 yr for soluble solids content (SSC), total solids content (TSC), fruit yield and fruit size to determine the effectiveness of combining elevated solids levels with high fruit yield and size following early generation selection. More than a quarter of the lines had significantly higher SSC levels than the recurrent tomato parent, Purdue 812 (P812). Several lines combined high SSC and TSC with high fruit yield and large fruit size to produce more dry matter yield per hectare or per fruit than P812. Two backcrosses were optimal for combining high SSC and high yield. SSC and TSC were negatively correlated with fruit size and, to a lesser degree, with fruit yield. Key words: Lycopersicon esculentum, soluble solids, total solids

Potassium iodate-induced proteolysis in ultra heat treated milk during storage: the role of β-lactoglobulin and plasmin

1986 ◽  
Vol 53 (4) ◽  
pp. 601-613 ◽  
Author(s):  
Mary B. Grufferty ◽  
Patrick F. Fox
Keyword(s):  
Whey Proteins ◽  
Inhibitory Effect ◽  
Casein Micelle ◽  
Ph Optimum ◽  
Heat Treated ◽  
Sh Group ◽  
90 C 30 ◽  
C 30 ◽  
Subsequent Storage ◽  
Β Lactoglobulin

SummaryThe report that addition of KI03 (0·1 mm) to milk before ultra high temperature (UHT) treatment induces extensive proteolysis during subsequent storage at 37 °C was confirmed. None was produced by addition of H202 KMn04 or K2Cr207. The pH optimum for KI03-induced proteolysis was between 7·0 and 8·0 and the temperature optimum 37—45 °C. β-Casein was particularly susceptible and the proteolysis pattern was similar to that caused by indigenous alkaline milk proteinase (MPA, plasmin). Addition of plasmin to milk before UHT treatment (140 °C/10 s) caused slight proteolysis during subsequent storage but addition of 0·1 mm-KI03 and plasmin caused extensive proteolysis which was prevented by addition of soyabean trypsin inhibitor, indicating the probable involvement of plasmin in KI03-induced proteolysis in UHT-treated milk. Equally extensive proteolysis occurred in serum protein-free casein micelle systems (SPFCM), with or without KI03, during storage at 37 °C following UHT treatment, indicating a role for whey proteins in KI03-induced proteolysis. Addition of β-lactoglobulin (β-lg) to a SPFCM system inhibited proteolysis, but extensive proteolysis occurred in a SPFCM system containing both β-lg and KI03. MPA-free Na caseinate (prepared by heating at 140 °C for 7 min) underwent extensive proteolysis when treated with plasmin before UHT treatment; proteolysis was inhibited by addition of °-lg to this system and KI03 reversed the inhibitory effect of β-lg. Plasmin proteolysis of isolated αs1-casein was inhibited by denatured β-lg (90 °C/30 min) at a level of 4 mg/ml but not by native β-lg. When denatured in the presence of KI03, β-lg had a lower free SH content than the control and was less inhibitory for plasmin in proteolysis of isolated αsl-casein. The results show that denatured β-lg inhibits plasmin proteolysis of caseins in UHT milk and that inhibition is prevented by KI03. This inhibition may occur via thiol–disulphide interchange, which is prevented if the SH group of ²-lg is oxidized by KI03, thus permitting the stimulatory effect of KI03 on proteolysis in UHT-treated milk.

scholarly journals Evaluation of the quality of Dahi available in Sylhet Metropolitan City

1970 ◽  
Vol 9 (1) ◽  
pp. 79-84 ◽  
Author(s):  
S Dey ◽  
A Iqbal ◽  
A Ara ◽  
MH Rashid
Keyword(s):  
Protein Content ◽  
Viable Count ◽  
Coliform Bacteria ◽  
Microbial Count ◽  
Total Viable Count ◽  
Total Solids ◽  
Metropolitan City ◽  
Significant Difference ◽  
Solids Content

The study was undertaken to evaluate the quality of Dahi available in Sylhet Metropolitan City. Dahi samples from five different Sweetmeat Shops namely Fulkoli, Banaful, Mohanlal, Modhuban and Shad were collected and analyzed. Significant difference in chemical (protein, fat, total solids, ash, acidity and pH) and microbiological status was found among different Dahi samples. Of the five Dahi Brands examined, Fulkoli Brand Dhai had the highest protein content (4.58 ± 0.24) and Shad Brand Dahi had the lowest protein content (4.01 ± 0.17). Fat content was highest in Fulkoli Brand (4.02 ± 0.13) and lowest in Shad Brand (2.10 ± 0.21). The highest total solids content was found in Dahi of Shad Brand (38.00 ± 2.23) and lowest total solids content was found in Banaful Brand Dahi (32.02 ±1.50). Highest Total Viable Count (log cfu/ml.) was recorded in the Dahi of Shad Brand (5.92±0.09) and lowest Total Viable Count was recorded in Mohanlal Brand Dahi (5.84±0.06). Coliform bacteria, Yeast and Mould were present in all the samples. From this experiment, it was found that Fulkoli Brand Dahi was the best in quality . Dahi of Banaful and Mohanlal were in 2nd and 3rd position in quality. Keywords: Fermented milk; Evaluation; Chemical analysis; Microbial count; Total viable count DOI: http://dx.doi.org/10.3329/jbau.v9i1.8748 JBAU 2011; 9(1): 79-83

Compression and impact strength of gels, prepared from fractionated whey proteins, in relation to composition and microstructure

1989 ◽  
Vol 56 (2) ◽  
pp. 275-284 ◽  
Author(s):  
Keith R. Langley ◽  
Margaret L. Green
Keyword(s):  
Impact Strength ◽  
Protein Content ◽  
Standard Method ◽  
Elastic Moduli ◽  
Whey Proteins ◽  
Surface Friction ◽  
Honeycomb Structure ◽  
Poisson's Ratio ◽  
Open Network ◽  
Β Lactoglobulin

SummaryGels varying in protein content and composition were prepared from whey proteins by a standard method and their compression and impact strengths were determined. No surface friction could be observed between the gels and the compression plates, and the Poisson's ratio was close to 0·5. Thus, the elastic moduli of the gels were determined. Compression and impact strengths and elastic moduli were related logarithmically to the β-lactoglobulin content of the protein powders. The strength and manner of fracture of the gels depended on the gel microstructure. Strong gels had a honeycomb structure consisting of a very tightly bound network, and failed by cracking on impact and by shear along cleavage planes in compression. Weaker gels had a loose open network with no definite means of fracture.

Heat-induced and other chemical changes in commercial UHT milks

2005 ◽  
Vol 72 (4) ◽  
pp. 442-446 ◽  
Author(s):  
Anthony J Elliott ◽  
Nivedita Datta ◽  
Boka Amenu ◽  
Hilton C Deeth
Keyword(s):  
Heat Treatment ◽  
Bovine Serum Albumin ◽  
Bovine Serum ◽  
Room Temperature ◽  
Whey Proteins ◽  
Thermally Induced ◽  
Heated Milk ◽  
Heat Treated ◽  
Induced Changes ◽  
Β Lactoglobulin

The properties of commercial directly and indirectly heated UHT milks, both after heating and during storage at room temperature for 24 weeks, were studied. Thermally induced changes were examined by changes in lactulose, furosine and acid-soluble whey proteins. The results confirmed previous reports that directly heated UHT milks suffer less heat damage than indirectly heated milk. During storage, furosine increased and bovine serum albumin in directly heat-treated milks decreased significantly. The changes in lactulose, α-lactalbumin and β-lactoglobulin were not statistically significant. The data suggest that heat treatment indicators should be measured as soon as possible after processing to avoid any misinterpretations of the intensity of the heat treatment.

Thermal denaturation of α-lactalbumin and β-lactoglobulin in cheese whey: effect of total solids concentration and pH

1979 ◽  
Vol 46 (1) ◽  
pp. 103-111 ◽  
Author(s):  
Robyn M. Hillier ◽  
Richard L. J. Lyster ◽  
Gordon C. Cheeseman
Keyword(s):  
Genetic Variants ◽  
Thermal Denaturation ◽  
Cheese Whey ◽  
Polyacrylamide Gel Electrophoresis ◽  
Electrostatic Charge ◽  
Total Solids ◽  
Solids Concentration ◽  
Lactose Concentration ◽  
Solids Content ◽  
Β Lactoglobulin

SUMMARYMeasurements of residual native protein remaining after heat treatment of cheese whey have been made using quantitative polyacrylamide gel electrophoresis. The results have been expressed in terms of kinetic constants. The effect of concentration was investigated up to 3 times the normal total solids content, dialysis treatments were used to study the effect of non-protein constituents, and the effect of pH was studied at pH 4, 6 and 9. The results indicated that increased total solids (TS) concentration slowed the denaturation of β-lactoglobulin A and B (β-lg A, β-lg B) but hastened the denaturation of α-lactalbumin (α-la). However, increased lactose concentration slowed the denaturation of both α-la and β-lg, perhaps by preventing formation of heat-induced complexes. Increased Ca concentration, up to 0.4 mg/ml, tended to slow the denaturation of both proteins, but further increase in Ca up to 0.9 mg/;ml produced little effect. The rate of denaturation of both α-la and β-lg was slower at pH 4 than at pH 6 or 9, and was probably slowest at the isoelectric point. However, not all the changes associated with pH could be explained in terms of net molecular electrostatic charge. The genetic variants of ′β-lg showed different heat stabilities – below 90 °C β-lgA was more stable than β-lgB, but above 90 °C the situation was reversed at all TS concentrations, and pH 6. However, at pH 4 and 9, °-lgA was less stable than °-lgB over the entire temperature range at normal concentration.

scholarly journals Manufacture of dahi from skim milk adding mango juice

2014 ◽  
Vol 43 (2) ◽  
pp. 128-131 ◽  
Author(s):  
MA Kabir ◽  
MH Rashid ◽  
MN Hassan ◽  
MF Afroz ◽  
FH Miraz
Keyword(s):  
Protein Content ◽  
Skim Milk ◽  
The Body ◽  
Total Solids ◽  
Ph Values ◽  
Significant Difference ◽  
Different Types ◽  
Mango Juice ◽  
Solids Content

The aim of this research was to prepare and evaluate the quality of dahi using skim milk fortified with 5, 10 and 15 percent of mango juice. The quality of prepared dahi was measured by organolaptic, chemical and microbiological tests. Significant difference was observed within the smell and taste score (p<0.05), the body and consistency score (p<0.01) and color and texture (p<0.05) of different types of dahi. Fat, ash and total solids content differed significantly (p<0.05) among the different types of dahi with mango juice but protein content and pH values did not differ significantly (p>0.05) among the different types of dahi with mango juice. There was no significant difference (p>0.05) in case of total viable organisms count but significant difference (p<0.05) was found in case of Coliform count among the different types of dahi with mango juice. From this study it was suggested that dahi could be prepared successfully by adding different proportion of mango juice with skim milk and 10% mango juice addition showed better result.DOI: http://dx.doi.org/10.3329/bjas.v43i2.20713 Bang. J. Anim. Sci. 2014. 43 (2): 128-131

Additive and dominance effects of the αs1-casein locus on milk yield and composition traits in dairy goats

2012 ◽  
Vol 79 (3) ◽  
pp. 367-374 ◽  
Author(s):  
Felicitas Vázquez-Flores ◽  
Hugo H Montaldo ◽  
José A Torres-Vázquez ◽  
Rogelio A Alonso-Morales ◽  
Amanda Gayosso-Vázquez ◽  
...  
Keyword(s):  
Protein Content ◽  
Milk Yield ◽  
Milk Fat ◽  
Genetic Effect ◽  
Data Sets ◽  
Dairy Goats ◽  
Total Solids ◽  
Breeding Programmes ◽  
Solids Content ◽  
Positive Effect

The objective of this study was to evaluate the effects of the CSN1S1 locus polymorphism on 305-d records of milk, fat, protein, lactose and total solids yields, fat, protein, lactose and total solids contents in Mexican dairy goats. A total of 514 lactation records belonging to Alpine (n=60), Saanen (n=105) and Toggenburg (n=74) goats, born from 2003 to 2006 in three herds were used. Discrimination between alleles E, F, N, A* (CSN1S1 A, G, H, I, O1 and O2) and B* (CSN1S1 B1, B2, B3, B4, C and L) were made by amplification of fragments of the gene CSN1S1 and digestion with the restriction endonuclease XmnI. In order to estimate additive and dominance effects, data sets including (1) all genotypes, and (2) only homozygote genotypes, were analysed using linear mixed models. The allele A*, had significant additive effects for protein content (0·21±0·07%;P=0·002) and total solids content (0·66±0·23%;P=0·005) when compared with allele F. An unfavourable additive effect of allele A* on milk yield was found in the Alpine breed (−81·4±40·2;P=0·046) when compared with allele F. Favourable dominance effects were found for some genotypes (P<0·05) for milk yield (A*N and B*N), fat yield (A*N and B*E), protein yield (A*N and B*E), lactose yield (A*N) and total solids yield (A*N). Also, unfavourable dominance effects were found (P<0·05) for protein content (A*B* and A*N) and total solids content (A*B*, A*N, and A*F). Allele A* was the only one with a positive effect for protein content. Significant allele-year interaction effects were also observed. The presence of significant dominance effects, estimated between specific pairs of alleles, challenged the purely additive nature of the genetic effect at the CSN1S1 locus. Implications from use of CSN1S1 effects in goat breeding programmes are presented.

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