Modelling formation and removal of biofilms in secondary dairy raw materials

Introduction. Microorganisms of dairy raw materials tend to adhere to the surfaces of processing equipment and form sustainable biofilms, which is a serious issue in the dairy industry. The goal of the present work was to investigate formation of biofilms on a glass surface in static model conditions, and removal of such biofilms by cleaning. Study objects and methods. The study objects were the permeates of skim milk, sweet whey and acid whey, as well as the biofilms formed and washings from glass slides. Biofilms were removed from the glass with detergents used in the dairy industry. Standard methods of determining microbiological and physicochemical properties were used to characterize the permeates. The biofilm structure and morphology of microorganisms participating in biofilm formation were investigated with a light spectroscopy. The efficiency of biofilm removal in a cleaning process was quantified with optical density of washings. Results and discussion. Biofilms in whey permeates formed slower compared to those in skimmed milk permeate during the first 24 h. Yeasts contributed significantly to the biofilm microflora in acid whey permeate throughout 5 days of biofilm growth. Well adhered biofilm layers were the most stable in skimmed milk permeate. The highest growth of both well and poorly adhered biofilm layers was observed in sweet whey permeate after 3–5 days. It was established that the primary attachment of microorganisms to a glass surface occurred within 8 h, mature multicultural biofilms formed within 48 h, and their partial destruction occurred within 72 h. Conclusion. The research results can be used to improve the cleaning equipment procedures in processing secondary dairy raw materials.

Download Full-text

LACTOSE HYDROLYSIS IN MILK AND MILK PRODUCTS BY BOUND FUNGAL BETA-GALACTOSIDASE

Journal of Milk and Food Technology ◽

10.4315/0022-2747-36.1.31 ◽

1973 ◽

Vol 36 (1) ◽

pp. 31-33 ◽

Cited By ~ 37

Author(s):

J. H. Woychik ◽

M. V. Wondolowski

Keyword(s):

Aspergillus Niger ◽

Skim Milk ◽

Lactose Hydrolysis ◽

Batch Reactors ◽

Galactosidase Activity ◽

Milk Products ◽

Sweet Whey ◽

Acid Whey ◽

Hydrolysis Of ◽

Beta Galactosidase

The β-galactosidase of Aspergillus niger was immobilized by glutaraldehyde coupling to porous glass beads and the bound enzyme evaluated for its applicability to hydrolysis of lactose in milk and milk products. Lactose in sweet whey and skim milk was hydrolyzed at approximately one-third the rate in acid whey. Non-lactose solids inhibited β-galactosidase activity. Greater efficiency of lactose hydrolysis was obtained with the bound enzyme in column operations than in stirred batch reactors.

Download Full-text

Estimation of Lactose Hydrolysis by Freezing Point Measurement in Milk and Whey Substrates Treated with Lactases from Various Microorganisms

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/64.6.1414 ◽

1981 ◽

Vol 64 (6) ◽

pp. 1414-1419

Author(s):

Shih-Ling Yeh Chen ◽

Joseph F Frank ◽

Morrison Loewenstein

Keyword(s):

Freezing Point ◽

Skim Milk ◽

Great Accuracy ◽

Lactose Hydrolysis ◽

Freezing Point Depression ◽

Low Fat ◽

Commercial Enzymes ◽

Sweet Whey ◽

Acid Whey ◽

Protein Components

Abstract β-Galactosidase concentrates obtained from several microorganisms were used to hydrolyze skim milk, low fat (2%) milk, sweet whey, acid whey, acid whey permeate, and acid whey concentrate. Among acid substrates, the freezing point depression for each 1% lactose hydrolyzed was the greatest with the lactase from Aspergillus niger (0.0501°H); among neutral substrates, the depression was greater in sweet whey (0.0495°H) and lesser in low fat milk (0.0445°H). All data were statistically significant. The average freezing point depression for each 1% lactose hydrolyzed was 0.0468°H (range 0.0436-0.0501°H). Oligosaccharides formed in the lactose hydrolysis, inconsistent freezing point readings of the cryoscope at the low freezing points measured, and protease contamination in some lactases may affect the precision of freezing point determination. Hydration and volume of non-protein components in commercial enzymes, unstable color complex formed by lactose in methylamine solution, and difficulty in the use of methylamine solution might cause variations in determination of lactose by the analytical procedure. These factors can be eliminated or minimized. This method is the simplest and quickest estimation of lactose hydrolysis, and it offers great accuracy and consistency

Download Full-text

Impact of Bovine Diet on Metabolomic Profile of Skim Milk and Whey Protein Ingredients

Metabolites ◽

10.3390/metabo9120305 ◽

2019 ◽

Vol 9 (12) ◽

pp. 305 ◽

Cited By ~ 3

Author(s):

Jonathan B. Magan ◽

Tom F. O’Callaghan ◽

Jiamin Zheng ◽

Lun Zhang ◽

Rupasri Mandal ◽

...

Keyword(s):

Mass Spectrometry ◽

Amino Acid ◽

Amino Acid Composition ◽

Perennial Ryegrass ◽

Milk Powder ◽

Skim Milk ◽

Skim Milk Powder ◽

Total Amino Acid ◽

Sweet Whey ◽

Acid Whey

The influence of bovine diet on the metabolome of reconstituted skim milk powder (SMP) and protein ingredients produced from the milk of cows fed on pasture or concentrate-based diets was investigated. Cows were randomly assigned to diets consisting of perennial ryegrass only (GRS), perennial ryegrass/white clover sward (CLV), or indoor total mixed ration (TMR) for an entire lactation. Raw milk obtained from each group was processed at pilot scale, to produce SMP and sweet whey, and SMP was further processed at laboratory scale, to yield ideal whey and acid whey. The total amino acid composition and metabolome of each sample were analyzed, using high-performance cation exchange and a targeted combination of direct-injection mass spectrometry and reverse-phase liquid chromatography–tandem mass spectrometry (LC–MS/MS), respectively. The nitrogen composition of the products from each of the diets was similar, with one exception being the significantly higher nonprotein nitrogen content in TMR-derived skim milk powder than that from the GRS system. Total amino acid analysis showed significantly higher concentrations of glycine in GRS- and CLV-derived sweet whey and acid whey than in those from TMR. The cysteine contents of CLV-derived ideal whey and acid whey were significantly higher than for TMR, while the valine content of GRS-derived acid whey was significantly higher than TMR. The phenylalanine content of GRS-derived ideal whey was significantly higher than that from CLV. Metabolomic analysis showed significantly higher concentrations of the metabolites glutamine, valine, and phosphocreatine in each ingredient type derived from TMR than those from GRS or CLV, while the serine content of each GRS-derived ingredient type was significantly higher than that in TMR-derived ingredients. These results demonstrate that the type of bovine feeding system used can have a significant effect on the amino acid composition and metabolome of skim milk and whey powders and may aid in the selection of raw materials for product manufacture, while the clear separation between the samples gives further evidence for distinguishing milk products produced from different feeding systems based on LC–MS/MS.

Download Full-text

Whey as an indicator for standardizing cow’s milk fat percentage for cheese production

International Journal of Business and Applied Social Science ◽

10.33642/ijbass.v6n3p3 ◽

2020 ◽

pp. 33-39

Author(s):

Prof. Asoc. Dr. Shurki MAXHUNI ◽

Prof.Asiss.Dr.Nerimane BAJRAKTARI

Keyword(s):

Milk Fat ◽

Economic Indicator ◽

Peculiar Feature ◽

Cow’S Milk ◽

Fat Percentage ◽

Cow's Milk ◽

Physical Chemical ◽

Heated Milk ◽

Sweet Whey ◽

Acid Whey

The dairy industry seems to have convinced the food industry that whey is a miracle product. The list of supposed benefits it gives to food is as long as your arm. Some of the benefits may be real. Whey is the liquid remaining after milk has been curdled and strained. It is a by-product of the manufacture of cheese or casein and has several commercial uses. To produce cheese, rennet or an edible acid is added to heated milk. This makes the milk coagulate or curdle, separating the milk solids (curds) from the liquid whey. Sweet whey is the byproduct of rennet-coagulated cheese and acid whey (also called sour whey) is the byproduct of acid-coagulated cheese. Sweet whey has a pH greater than or equal to 5.6, acid whey has a pH less than or equal to 5.1. Whey is also a great way to add sweetness to a product without having to list sugar as an ingredient as whey contains up to 75% lactose. And it sounds healthy. This study is done to research the examinations for the production of mozzarella cheese from Cow’s milk, after research and analyses of a physical-chemical peculiar feature of whey from coagulum. We have followed the processes from the drying of whey from the coagulum analyzer's physical-chemical peculiar feature. We carried out three experiments. For every experiment, we took three patterns and analyzed the physical-chemical. The calculation was appraised statistically. This paper deals with the research of% of whey fat during the process of milk production from standardized to non-standardized milk. Where% of whey fat should be an economic indicator for standardizing milk for dairy production.

Download Full-text

Effect of the electro-dialysis treatment temperature on the microflora of skim milk permeate

Dairy Industry ◽

10.31515/1019-8946-2018-10-14-15 ◽

2018 ◽

pp. 14-15

Author(s):

Anisimov G.S. ◽

◽

Evdokimov I.A. ◽

Ryabtseva S.A. ◽

Donskih A.N. ◽

...

Keyword(s):

Skim Milk ◽

Treatment Temperature ◽

Dialysis Treatment ◽

Milk Permeate

Download Full-text

Formation and removal of biofilms in skim milk permeate

Dairy Industry ◽

10.31515/1019-8946-2019-6-48-50 ◽

2019 ◽

pp. 48-50 ◽

Cited By ~ 1

Author(s):

O.V. Salova ◽

◽

S.A. Ryabtseva ◽

Y.A. Tabakova ◽

G.S. Anisimov ◽

...

Keyword(s):

Skim Milk ◽

Milk Permeate

Download Full-text

Efficiency of sweet whey fermentation with psychrophilic methanogens

Environmental Science and Pollution Research ◽

10.1007/s11356-021-14095-y ◽

2021 ◽

Author(s):

Marcin Dębowski ◽

Ewa Korzeniewska ◽

Joanna Kazimierowicz ◽

Marcin Zieliński

Keyword(s):

Removal Efficiency ◽

Natural Environment ◽

Waste Product ◽

Dairy Industry ◽

Psychrophilic Bacteria ◽

Methane Fermentation ◽

Anaerobic Bioreactors ◽

Type Flow ◽

Sweet Whey ◽

Flow Through

AbstractSweet whey is a waste product from the dairy industry that is difficult to manage. High hopes are fostered regarding its neutralization in the methane fermentation. An economically viable alternative to a typical mesophilic fermentation seems to be the process involving psychrophilic bacteria isolated from the natural environment. This study aimed to determine the feasibility of exploiting psychrophilic microorganisms in methane fermentation of sweet whey. The experiments were carried out under dynamic conditions using Bio Flo 310 type flow-through anaerobic bioreactors. The temperature inside the reactors was 10 ± 1 °C. The HRT was 20 days and the OLR was 0.2 g COD/dm3/day. The study yielded 132.7 ± 13.8 mL biogas/gCODremoved. The CH4 concentration in the biogas was 32.7 ± 1.6%, that of H2 was 8.7 ± 4.7%, whereas that of CO2 reached 58.42 ± 2.47%. Other gases were also determined, though in lower concentrations. The COD and BOD5 removal efficiency reached 21.4 ± 0.6% and 17.6 ± 1.0%, respectively.

Download Full-text

DRIED SKIMMED MILK, BREAST-FEEDING, AND ILLNESS EPISODES

PEDIATRICS ◽

10.1542/peds.70.2.245 ◽

1982 ◽

Vol 70 (2) ◽

pp. 245-245

Author(s):

Robert J. Haggerty

Keyword(s):

Breast Feeding ◽

Controlled Trial ◽

Skim Milk ◽

Food Supplement ◽

Health Clinics ◽

Significant Difference ◽

Methodological Problems ◽

Skimmed Milk ◽

Health Institutions ◽

And Child Health

In a controlled trial mothers and children attending urban maternal and child health clinics in Khartoum Province were given a fortnightly take-home food supplement of 1 kilogram of dried skimmed milk or an equivalent amount of local beans. There were approximately 300 children aged 6 to 26 months in each group and each child was followed for three to six months. A comparison of the two groups showed: (a) that the dried skimmed milk group mothers were more likely to continue breast-feeding; (b) there was no evidence to associate dried skim milk with an increased incidence of episodes of diarrhea, fever, or vomiting; (c) the utilization of health institutions was very similar in the two groups; and (d) there was no significant difference in the mothers' assessment of the proportion of children with a "poor" appetite in either group. This trial met with considerable methodological problems and the results should therefore be interpreted cautiously. There is a great need for more and better designed trials to assess the possible adverse effects of dried skim milk.

Download Full-text

Potential Transmission of Foot-and-Mouth Disease in Whey Constituents1

Journal of Food Protection ◽

10.4315/0362-028x-41.8.631 ◽

1978 ◽

Vol 41 (8) ◽

pp. 631-633 ◽

Cited By ~ 5

Author(s):

J. H. BLACKWELL

Keyword(s):

Foot And Mouth Disease ◽

Mouth Disease ◽

Fmd Virus ◽

Sweet Whey ◽

Foot And Mouth ◽

Acid Whey ◽

Camembert Cheese ◽

Β Lactoglobulin

Whey and whey constituents were prepared from the milk of cows infected with foot-and-mouth disease (FMD) virus. The virus was detected in the sweet whey by-product of Cheddar and Camembert cheese but was not detected in the acid whey by-product of casein manufacture. Whey constituents, α-lactalbumin, β-lactoglobulin, and lactose, produced from sweet whey were noninfectious when inoculated into cattle. These products do not appear as likely candidates for the transmission of FMD.

Download Full-text