Compositional: basic chemical composition of raw material and by processing e. . Quality of butter made from fat of milk (can’t put in grape seed oil) 5. Physiological functionality, nutrition, technological functionality: qualitative function, whip egg whites, boiled Solution: Emulsion: Colloidal suspension: Milk composition: the quantities of the various main constituents of milk can vary considerably between cows of different breeds and between individual cows of the same breed.
Therefore only limit values can be stated for the variations o Casein proteins (3. 5% vow): o Casein in micelles With Ca * P, sensitive to enzymes and acid, does tot taste owe (20%a+;illogicality): in serum, intercultural properties, not acid sensitive, sensitive to heat; more complete protein than casein o During denomination, casein adheres to beta-illogicality o Lactose (4. % w/v): disaccharide (glucose + calaboose) o limited sweetness (unsuitable as a sweetening agent,can be improved by hydrolysis) o reducing sugar (Millard RSN upon heating) o limited solubility in water (crystallization in highly concentrated dairy foods: ice cream’, whey cheese, sweetened condensed milk) o bacteria utilize lactose in fermentations (LAB) Lactose intolerance: do not secrete enough lactate, lactose escapes digestion, builds up in colon and gets fermented; natural occurrence in all mammals.
Industry responds: ; Lactose hydrolysis milk (lactated, lactose): in vitro breakdown of lactose by enzymes to monasteries by Beta-Classified o Fat (3. 5% in globules! 36-egg tat in IL milk; found in TAG, 2% other components soluble in fat phosphoric, cholesterol, carotids, vitamins DAD, 0. 1-0. % FAA): o Fat globules with globule membranes o Saturated (70%) Unsaturated (30%: MEJIA, TEA): the milk VA are rived almost equally from two sources, the feed and the microbial activity in the rumen of the cow o Size/ behavior o Density, creaming o Sensory effects o Health effects o Soluble in organic solvents o Minerals (Ca * P) (1% w/v): soluble (Nasal), colloidal (Cal o Free and micelle calcium: holds micelles together, related to cheese making, gel formation o Most abundant = potassium o Water (87% w/v): solvent (solutes decrease freezing point) o Other compounds: o Enzymes: plasmid, lipase, alkaline phosphates (role in cheese ripening) ; Proteases, propitiates, peptidases; major protease is Plasmid: some are inactivated by heat and some not. Protein degradation can be undesirable and result in bitter off-flavor or it may provide a desirable texture to cheese during ripening. Lipase: agitation during processing may bring LIP into contact with the milk fat resulting in fat degradation and off-flavors, bastardization will inactivate the lipase in milk and increase shelf life ; Phosphates (alkaline, acid): heat sensitive enzyme used as indicator of bastardization, If properly pastured, alkaline phosphates (and electrophoresis) is inactivated o Microbial enzymes: shortstops -? spoilage vitamins (riboflavin, thiamine, C + D) Bulk Milk: Mastitis: microbial infection of the udder . Accompanied by increases in bacterial numbers (Inc. Human pathogens) . Dramatic increase in somatic cells: leukocytes (WEB) epithelial cells from the udder . Sub-clinical and clinical mastitis: health aspects, milk yield . Antibiotics in milk (allergy, antibiotic resistant microorganisms, fermentation) .
Shortstops still could be a problem (even if rapidly cooled to less than 2 degrees, which would inhibit pathogenic and spoilage bacteria): capable of surviving or thriving in a cold environment Bacteria Count in V-arm Milk: S 50 thousand is good, 50 – 500 thousand is average, and 0. – 5 million is poor (3 days) Casein Micelle: 2 glues: k-casein & calcium phosphate Aim of Bastardization: complete deactivation of vegetative forms of microorganisms (pathogenic, potentially pathogenic, toxicologist), reduction in numbers of other spoilage organisms, partial deactivation of enzymes; mycobacterium tuberculosis + collegial burnet Microorganisms that survive are putrefactive (protein breakdown, acidity development) Types of Bastardization: 1. TEST: High Temperature Short Time a.
Minimal conditions: ICC for 15 seconds b. Goal: deactivate pathogenic microorganisms (also deactivates other bacteria ND enzymes that increase shelf life) c. Carried out as a continuous process using a plate heat exchanger i. Corrugated stainless steel plates pressed together ii, Alternate flow of water and milk iii. Rapid transfer of heat because flow is very thin film iv, Rubber gaskets preventing mixing of the two streams v. To maximize the heat record. ‘ere, cold milk is heated by the hot pastured milk that is thereby cooled – REGENERATION section. Section can be split with the milk undergoing standardization and or homogeneities during this phase Mi.
Then to holding tube (timing pump) vii. Control thermometer is connected to automatic return valve (improperly pastured diverted back to tank) 2. L T H: Low Temperature Holding a. Batch: ICC for 30 minutes Bastardization < 100 oc ; 90-950C for 1-2 seconds (cream) seconds (yogurts, ferment milk) ; 72-74;C for 15-30 seconds (milk) followed by rapid cooling seconds (cheese, thermization) ; 650C for 30 minutes (farmhouse) For sterilizing-. 100 oc Thermization < 100 oc 65 OCfor 15 seconds ; 85-90CCfor 1-2 ; 65-680Cforfew Ultrapasteurization + no aseptic packaging > 100 co CZ for 4 seconds OUT * aseptic packaging > 100 co ICC for 4-8 seconds
Direct heating: steam into milk or milk into steam, condensation releases latent heat (instant heating), expansion temperature returns to atmospheric pressure (instantaneous cooling) *latent heat tot condensation – latent heat of vaporization Indirect heating: bastardization under pressure (heat exchanger where both fluids are under pressure but heat transfer is not instantaneous) Technological Heating Effectiveness of bastardization for various products: 1. Temperature used _ time of heat exposure 3. The come-up time _ thickness of the heated layer 5. The nature of the product 6. Intensity Of mixing during the heat treatment (laminar vs.. Rebutter) Chemical changes: 1. Some denomination of whey proteins 2. Some destruction of Vitamins 3. Soluble forms of Ca salts of phosphoric acid transferred onto casein micelles 4. Heat treatment at gig causes noticeable changes of smell and taste resulting from Beta-illogicality SSH-groups liberation 5. Significant deactivation of vegetative bacteria Homogeneities: ; prevents the formation off cream layer in full cream milk why a reduction in the size Toyota globules to Imp leads to at least wood increase in the tat globule area ; as a result the stability of the emulsion is improved (secondary fat lobule membrane developed) ; accomplished by equipment called homogeneity ; High pressure homogeneities: high pressure, high flow velocity, minimum temperature Stokes Law: to reduce sedimentation (Velocity approach O) why standardize bore homogenate) – reduce the particle size – increase viscosity Of continuous phase – minimize the density difference Increased surface area Of fat globules covered by the casein and Whey protein molecules Following usually homogeneity: ; market milk ; cream ; condensed milk ; Ice cream mixes ; milk tort yogurt production ; milk for milk powder production Impact of homogeneities: the stability of milk fat emulsion increased, no coalescence of fat droplets, no cream layer formation ; prevents the adhesion of fat on the packaging material surface ;milk with lower fat content has a fuller mouthful ; finer consistency in fermented products ; some argument whether it reduces the size of casein micelles, reducing the time of coagulation, leading to softer curd, holding more whey Pat Separation/Standardization ; continuous centrifuge (disk centrifuge) o one inlet: milk Stream o two outlets: skimmed milk moves outward, cream moves inward (20-40% fat) o the two streams mixed to get desired fat content Elements Of Technology 2 stage: 1. Sterilization of the product outside the package 2. Filling the product into pre-sterilized package a. Activation of the microbial life at the LILT conditions does not lead to complete deactivation of enzymes, thus shelf life limited; best before date applies) Extended Shelf-life Milk (SSL): result of factorization (separation of spores and bacterial cell with the high speed centrifuge) WAP Index: whey protein nitrogen Evaporators (use heat) Drier (use heat) Effects: – lactose: solubility, hygroscopic, crystallization – heat load, sensitivity of whey protein – emulsion characteristics flavor losses – quality effects: solubility, reconstitution’s, hittable, instantiation Hygroscopic: tending of a substance to absorb moisture from the air The principle constituents of normal salted butter (water-in-oil emulsion): 1 (80-82%) 2. Water (15. 6-17. 6%) 3. Salt (1. 2%) 4. Protein, ca, 5. Some fat soluble vitamins – The fat MUST be unadulterated milk fat why?
Sweet cream butter: is butter from cream that is not allowed to sour (just about any butter); should taste tot cream Cultured (sour) cream butter: made from cream fermented why suitable cultures producing lactic acid and dedicated (silky): should taste of dedicated. The aroma is richer, the butter yield higher and there is less risk of reinsertion after temperature treatment as the bacteria culture suppresses undesirable micro-organisms. If ripening is desired for the production of cultured butter, mixed cultures of S. Careerism, S, lactic vary, deescalating, or Leucosis are used and the cream is ripened to pH 5. 5 @ICC and then pH 4. 6 @ 130. Most flavor development occurs between pH 5. 46; ripening usually takes 12-ours SIN = solids non-fat Butter making is based on the controlled desalination of the oil-in-water emulsion Of cream, selective concentration Of the lipid components by removal Of he aqueous fraction (buttermilk) and subsequent formation of a stable water-in- Oil (semisolid emulsion). TWO principle technological avenues for the conversion of the ON/ into W/O emulsion: 1. Churning a. Traditional batch churning b. Continuous churning (Frizz process) 2. High-fat content cream (Moleskin process): repeat centrifugation and final conversion Anhydrous milk tat: Butter is at least 80% fat (and the rest is It the rest is removed, the final product is 100% milk fat, no water, thus AMP (in Indian ghee), Ghee is made by melting butter and removing the heavier aqueous phase
Emulsion: a find dispersion of minute droplets of one liquid in another in which it is not soluble or miscible ICE CREAM: – A mixture of ice crystals embedded in – Unfrozen highly supersaturated solution that also contains fat clusters and globules – An emulsion with air whipped in during the freezing process FOAM Fermented (cultured) dairy products + cheese Microbial transformations: ; Lactose: fermented into lactic acid ; Casein: broken down to peptides (manufacture, ripening) ; Fat (transformations during cheese ripening) ; Carbon dioxide, acetic acid, dedicated, accidentally, stones, and several other absences are formed in the conversion process, and these give the products their characteristic taste and aroma (cottage cheese/quark these include some elements of checkmating i. E. Separation of whey but no ripening) Technological transformations 1. Fermented products: one phase – manufacturing 2.
Cheese: two phases – manufacturing & ripening (initial acidity development by dairy starter cultures, milk clotting by enzymes, separation of curd (casein and fat) from the liquid (whey) and then ripening (in most cases) a, Ripening: breakdown of protein, tat, lactose by microorganisms and/or their enzymes, there reactions, mechanical handling 1st Step in cheese making: coagulation of milk casein 1. Acid coagulation: a. Souring by LAB b. Addition of acid (lactic acid, tartaric acid, acetic acid, glucose-lactose) 2. Rennet coagulation (breaks down casein) a. Proteolysis enzymes (produced in any mammalian stomach): commission, pepsin b. Plant enzymes c. Microbial enzymes From genetically modified engineered vectors. Does yogurt contain lactose? Yogurt contain all components? T or Why is food preservation important?
Types of preservation: KNOW 3 Fermentation With yeast * collaboration – produces vinegar (a good preservative) Sterilized Pastured Dried Syrup Frozen Salting Smoking Retrogression’s of preserving food by cooking in a sealed airtight container Question: Criteria for Food Quality good Deterioration: ; Loss of safety ; Loss of nutrition ; Low of shelf life ; Loss Of Reorganization desirability (acting or involving the use Of the sense organs) Major Causes of Food Deterioration: (occur simultaneously) I. Biochemical: a. Growth of microorganisms, bacteria, yeasts, and molds ; Beneficial: LAB, yeast, extractor or collaboration, molds ; Spoilage: mold, souring, rancid, lollipops ; Pathogenic b.
