Biomaterial Database

The effect of immunoglobulins and somatic cells on the gravity separation of fat, bacteria, and spores in pasteurized whole milk. 2014

S R Geer, and D M Barbano

Northeast Dairy Food Research Center, Department of Food Science, Cornell University, Ithaca, NY 14853.

Our objective was to determine the role that immunoglobulins and somatic cells (SC) play in the gravity separation of milk. The experiment comprised 9 treatments: (1) low-temperature pasteurized (LTP; 72°C for 17.31s) whole milk; (2) LTP (72°C for 17.31s) whole milk with added bacteria and spores; (3) recombined LTP (72°C for 17.31s) whole milk with added bacteria and spores; (4) high-temperature pasteurized (HTP; 76°C for 7min) whole milk with added bacteria and spores; (5) HTP (76°C for 7min) whole milk with added bacteria and spores and added colostrum; (6) HTP (76°C for 7min) centrifugally separated, gravity-separated (CS GS) skim milk with HTP (76°C for 7min) low-SC cream with added bacteria and spores; (7) HTP (76°C for 7min) CS GS skim milk with HTP (76°C for 7min) high-SC cream with added bacteria and spores; (8) HTP (76°C for 7min) CS GS skim milk with HTP (76°C for 7min) low-SC cream with added bacteria and spores and added colostrum; and (9) HTP (76°C for 7min) CS GS skim milk with HTP (76°C for 7min) high-SC cream with added bacteria and spores and added colostrum. The milks in the 9 treatments were gravity separated at 4°C for 23h in glass columns. Five fractions were collected by weight from each of the column treatments, starting from the bottom of the glass column: 0 to 5%, 5 to 90%, 90 to 96%, 96 to 98%, and 98 to 100%. The SC, fat, bacteria, and spores were measured in each of the fractions. The experiment was replicated 3 times in different weeks using a different batch of milk and different colostrum. Portions of the same batch of the frozen bacteria and spore solutions were used for all 3 replicates. The presence of both SC and immunoglobulins were necessary for normal gravity separation (i.e., rising to the top) of fat, bacteria, and spores in whole milk. The presence of immunoglobulins alone without SC was not sufficient to cause bacteria, fat, and spores to rise to the top. The interaction between SC and immunoglobulins was necessary to cause aggregates of fat, SC, bacteria, and spores to rise during gravity separation. The SC may provide the buoyancy required for the aggregates to rise to the top due to gas within the SC. More research is needed to understand the mechanism of the gravity-separation process.

UI	MeSH Term	Description	Entries
D007136	Immunoglobulins	Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.	Globulins, Immune,Immune Globulin,Immune Globulins,Immunoglobulin,Globulin, Immune
D008892	Milk	The off-white liquid secreted by the mammary glands of humans and other mammals. It contains proteins, sugar, lipids, vitamins, and minerals.	Cow Milk,Cow's Milk,Milk, Cow,Milk, Cow's
D003126	Colostrum	The thin, yellow, serous fluid secreted by the mammary glands during pregnancy and immediately postpartum before lactation begins. It consists of immunologically active substances, white blood cells, water, protein, fat, and carbohydrates.	Colostrums
D004041	Dietary Fats	Fats present in food, especially in animal products such as meat, meat products, butter, ghee. They are present in lower amounts in nuts, seeds, and avocados.	Fats, Dietary,Dietary Fat,Fat, Dietary
D005504	Food Analysis	Measurement and evaluation of the components of substances to be taken as FOOD.	Analysis, Food,Analyses, Food,Food Analyses
D005506	Food Contamination	The presence in food of harmful, unpalatable, or otherwise objectionable foreign substances, e.g. chemicals, microorganisms or diluents, before, during, or after processing or storage.	Food Adulteration,Adulteration, Food,Adulterations, Food,Contamination, Food,Contaminations, Food,Food Adulterations,Food Contaminations
D005516	Food Microbiology	The presence of bacteria, viruses, and fungi in food and food products. This term is not restricted to pathogenic organisms: the presence of various non-pathogenic bacteria and fungi in cheeses and wines, for example, is included in this concept.	Microbiology, Food
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013171	Spores, Bacterial	Heat and stain resistant, metabolically inactive bodies formed within the vegetative cells of bacteria of the genera Bacillus and Clostridium.	Bacterial Spores,Bacterial Spore,Spore, Bacterial