Milk and Dairy Foods ANS 232 John A. Partridge 2100B South Anthony Hall [email_address]

Definition of milk. "The lacteal secretion, practically free from colostrum, obtained by the complete milking of one or more healthy cows, which contains not less then 3.25% of milkfat and not less then 8.25% milk‑solids‑not‑fat.” PMO - Pasteurized Milk Ordinance (Food secreted for newborns)

"The lacteal secretion, practically free from colostrum, obtained by the complete milking of one or more healthy cows, which contains not less then 3.25% of milkfat and not less then 8.25% milk‑solids‑not‑fat.”

PMO - Pasteurized Milk Ordinance

(Food secreted for newborns)

Table 1. Per Capita Consumption of Milk and Milk Products in Various Countries. Country Beverage Flavored Fermented Cheeses Cream Butter Finland 186.3 37.1 11.8 1.9 16.0 Norway 164.7 14.7 13.5 2.4 8.6 Sweden 145.1 27.2 15.4 2.9 8.7 Netherlands 91.2 21.0 19.1 14.9 1.0 7.2 France 78.1 6.0 13.6 21.8 0.9 14.1 Germany 70.1 8.6 10.5 16.8 1.7 14.9 Austria 134.1 2.5 9.5 9.6 1.2 8.8 Italy 79.5 3.3 17.5 0.8 2.3 Greece 54.2 1.7 6.0 22.2 0.3 2.7 UK 123.4 0.7 3.6 7.5 0.8 8.4 Ireland 182.7 3.2 4.9 0.7 11.8 USA 96.9 4.4 2.1 10.9 0.6 3.8 Canada 102.6 4.2 3.2 11.7 1.0 7.8 India 48.3 4.2 0.2 0.0 21.1 Australia 96.0 9.7 3.0 8.5 1.2 6.4 Japan 38.0 6.2 7.2 1.0 0.1 1.1 Source: International Dairy Federation

Gross Chemical Composition . Average composition. 87.3% Water 3.7% Fat 3.4% Protein 4.9% Lactose 0.7% Ash

Average composition. 87.3% Water 3.7% Fat 3.4% Protein 4.9% Lactose 0.7% Ash

Species Table 3. Composition of Milk from Different Mammalian Species (per 100 g fresh milk). Protein (g) Fat (g) Carbohydrate (g) Energy (kcal) Cow 3.2 3.7 4.6 66 Human 1.1 4.2 7.0 72 Water Buffalo 4.1 9.0 4.8 118 Goat 2.9 3.8 4.7 67 Donkey 1.9 0.6 6.1 38 Elephant 4.0 5.0 5.3 85 Monkey, rhesus 1.6 4.0 7.0 73 Mouse 9.0 13.1 3.0 171 Whale 10.9 42.3 1.3 443 Seal 10.2 49.4 0.1 502

Cow's Milk Breed Table 4. Gross composition of milk of various breeds, g/100g. Body Wt. Milk Yield Fat Protein Lactose Ash Total Solids (kg) (kg) (%) (%) (%) (%) (%) Holstein 640 7360 3.54 3.29 4.68 0.72 12.16 Brown Swiss 640 6100 3.99 3.64 4.94 0.74 13.08 Ayrshire 520 5760 3.95 3.48 4.60 0.72 12.77 Guernsey 500 5270 4.72 3.75 4.71 0.76 14.04 Jersey 430 5060 5.13 3.98 4.83 0.77 14.42 Shorthorn 530 5370 4.0 3.32 4.89 0.73 12.9 Holstein: 12.16% T.S. x 7360 kg/lactation = 895 kg of total solids produced/lactation (140% of her body wt.!) Jersey: 14.42% T.S. x 5060 kg/lactation = 730 kg of total solids produced/lactation (170% of her body wt.!)

Grades of Milk Grade A Temperature<45 F(7C) in 2 h Bacteria 100,000/ml (300,000/ml commingled) Antibiotics.005 IU detection limit (16mm zone) Somatic cells 1,000,000/ml Grade B or Manufacturing Milk

Grade A

Temperature<45 F(7C) in 2 h

Bacteria 100,000/ml (300,000/ml commingled)

Antibiotics.005 IU detection limit (16mm zone)

Somatic cells 1,000,000/ml

Grade B or Manufacturing Milk

Facilities and Equipment Types of milking systems Parlors Around the barn Bucket

Types of milking systems

Parlors

Around the barn

Bucket

Precautions at the producer level. Herd Health Disease affects milk composition (economic (Ec) issue) Antibiotics (public health (PH) issue) Added Water (Ec) Pesticides and other chemicals (PH) Aflatoxin and other toxins from natural sources (PH) Sanitation program (PH and Ec)

Herd Health

Disease affects milk composition (economic (Ec) issue)

Antibiotics (public health (PH) issue)

Added Water (Ec)

Pesticides and other chemicals (PH)

Aflatoxin and other toxins from natural sources (PH)

Sanitation program (PH and Ec)

IV. Milk Processing Filtering Storage (always below 4 C to prevent outgrowth of Staph. aureus) Centrifugal Processes Pasteurization Homogenization Cooling Packaging Storage and Distribution

Filtering

Storage (always below 4 C to prevent outgrowth of Staph. aureus)

Centrifugal Processes

Pasteurization

Homogenization

Cooling

Packaging

Storage and Distribution

Phase I - Preparations Sampling Manhole with dipper Odor and appearance Lab sample for acceptance In-line sampler Inventory & quality control

Sampling

Manhole with dipper

Odor and appearance

Lab sample for acceptance

In-line sampler

Inventory & quality control

Co-mingled sample at the plant

Individual farm samples for antibiotics, composition, somatic cell and bacteria counts

Phase II - Unloading Vents open before pumping commences $$$$ High capacity centrifugal pumps Up to 600 gallons per minute Filtration and/or clarification - optional

Vents open before pumping commences $$$$

High capacity centrifugal pumps

Up to 600 gallons per minute

Filtration and/or clarification - optional

Typical Receiving Operations

Phase III - Cleaning the Tanker CIP (Clean-in-Place) safe effective Tagged before leaving plant. Pump and exterior of the truck are cleaned while CIP is running. NOT while milk is unloading.

CIP (Clean-in-Place)

safe

effective

Tagged before leaving plant.

Pump and exterior of the truck are cleaned while CIP is running.

NOT while milk is unloading.

Receiving Tests Titratable Acidity (TA) Direct Microscopic Count (DMC) Bacteria Screening Somatic Cell Screening Antibiotic Residue Screening Beta Lactam (Penicillin family) every load Others on a random basis

Titratable Acidity (TA)

Direct Microscopic Count (DMC)

Bacteria Screening

Somatic Cell Screening

Antibiotic Residue Screening

Beta Lactam (Penicillin family) every load

Others on a random basis

Silo Tank Equipment 1. Agitator 2. Manhole 3. Temperature indicator 4. Low-level electrode 5. Pneumatic level indicator 6. High-level electrode Note: Tank vents to the interior of the building.

1. Agitator

2. Manhole

3. Temperature indicator

4. Low-level electrode

5. Pneumatic level indicator

6. High-level electrode

Note: Tank vents to the interior of the building.

Milk Storage - Regulatory Requirements Cleaned when emptied. Must be emptied at least every 72 hours. >24 hours in tank 7-day temperature recording device

Cleaned when emptied.

Must be emptied at least every 72 hours.

>24 hours in tank

7-day temperature recording device

Pasteurization Purposes Destroy pathogens --PRIMARY Destroy spoilage Organisms -- Secondary but very important Time-temperature relationships Equivalent heat treatments 145F for 30 m 161F for 15 s 191F for 1 s 212F for .01s Cooked flavor and creamline Overprocessing to obtain shelflife improvements may be more detrimental to product than helpful.

Purposes

Destroy pathogens --PRIMARY

Destroy spoilage Organisms -- Secondary but very important

Time-temperature relationships

Equivalent heat treatments

145F for 30 m

161F for 15 s

191F for 1 s

212F for .01s

Cooked flavor and creamline

Overprocessing to obtain shelflife improvements may be more detrimental to product than helpful.

Plate Heat Exchanger

High-Temperature, Short-Time Pasteurizer

Centrifugal processes.

Separation

Homogenization Reduction of fat globules from 3-20µm to <2µm Same factors that effect the rate of separation in centrifugal processes differences in densities diameter of particles to be separated residence time viscosity drag forces on particle

Reduction of fat globules from 3-20µm to <2µm

Same factors that effect the rate of separation in centrifugal processes

differences in densities

diameter of particles to be separated

residence time

viscosity

drag forces on particle

Raw Milk ( 3-20  m globules)

Homogenized milk ( <2  m globules)

Fluid Milk Products Whole Milk >3.25% Milkfat; >8.25% Milk-solids-not-fat (MSNF) Optional except for school milk: Vitamin D (400 IU/Quart) Reduced Fat Milk 25% reduction in Fat Lowfat Milk > 3 grams fat per serving, 1 cup Vitamin A (2000 IU/Quart) Optional except for school milk: Vitamin D (400 IU/Quart) Non-Fat Milk > 0.5 grams fat per serving, 1 cup Vitamin A (2000 IU/Quart) Optional except for school milk: Vitamin D (400 IU/Quart)

Whole Milk

>3.25% Milkfat; >8.25% Milk-solids-not-fat (MSNF)

Optional except for school milk: Vitamin D (400 IU/Quart)

Reduced Fat Milk

25% reduction in Fat

Lowfat Milk

> 3 grams fat per serving, 1 cup

Vitamin A (2000 IU/Quart)

Optional except for school milk: Vitamin D (400 IU/Quart)

Non-Fat Milk

> 0.5 grams fat per serving, 1 cup

Vitamin A (2000 IU/Quart)

Optional except for school milk: Vitamin D (400 IU/Quart)

Fluid Milk Products Heavy Cream > 36% milkfat Light Whipping Cream > 30% but <36% milkfat Light Cream > 18% but <30% milkfat Half-and-Half > 10.5% but <18% milkfat

Heavy Cream

> 36% milkfat

Light Whipping Cream

> 30% but <36% milkfat

Light Cream

> 18% but <30% milkfat

Half-and-Half

> 10.5% but <18% milkfat

Butter and Powder Butter Whole milk Powder Non Fat Dry Milk (NFDM) Powder Specialty Powders Evaporated milk

Butter

Whole milk Powder

Non Fat Dry Milk (NFDM) Powder

Specialty Powders

Evaporated milk

Cheese

Color is added to the milk and allowed to mix thoroughly.

Rennet is used to coagulate the curd and to separate the whey, or watery portion of milk, from the solids.

After addition of the rennet, the milk is allowed to sit undisturbed. The resulting curd is tested with a knife.

The curds are stirred as they are heated in a cooking step.

The cut curds are allowed to rest so the culture can grow. The pieces are turned every 15 minutes.

The cheese molds are filled in preparation for pressing.

Pressed, unripened cheese.

Dairy Processing Handbook Automated Cheddar Cheese Manufacture

Cheese Classification Fresh Cheeses Cottage, Cream Acid coagulation Bacterial w/o Eyes Rennet Coagulation Cheddar, Colby, Jack Bacterial w/ Eyes Carbon Dioxide, Propionic Acid Swiss, Dagano Mold Ripened Blue, Camembert Bacteria Smear Limburger, Muenster Pasta Filata (Pulled Curd) Mozzarella, Provalone

Fresh Cheeses

Cottage, Cream

Acid coagulation

Bacterial w/o Eyes

Rennet Coagulation

Cheddar, Colby, Jack

Bacterial w/ Eyes

Carbon Dioxide, Propionic Acid

Swiss, Dagano

Mold Ripened

Blue, Camembert

Bacteria Smear

Limburger, Muenster

Pasta Filata (Pulled Curd)

Mozzarella, Provalone

Cheese and Related Products cont’d Pasteurized Processed American Slices Velvetta Cold Pack Chocolate Cheese Wispread Whey Whey powder Whey protein concentrate

Pasteurized Processed

American Slices

Velvetta

Cold Pack

Chocolate Cheese

Wispread

Whey

Whey powder

Whey protein concentrate

Fermented Dairy Foods Yogurt fob vs prestirred Spoonable vs drinkable Probiotic Cultures Buttermilk Sour Cream Non-fat?

Yogurt

fob vs prestirred

Spoonable vs drinkable

Probiotic Cultures

Buttermilk

Sour Cream

Non-fat?

Ice Cream and Frozen Desserts Compositional Requirements Ice Cream > 10% milkfat; > 20% total milk solids Must weigh > 4.5 lb/gallon Must contain > 1.6 lb Total Solids/gallon Reduced Fat Ice Cream 25% reduction in fat content ( < 7.5% and > 3% milkfat) Lowfat Ice Cream 3 g fat per serving (½ cup) (<3% milkfat) Nonfat Ice Cream ½ g milkfat per serving (½ cup) NLEA vs. Old Standards of Identity

Compositional Requirements

Ice Cream

> 10% milkfat; > 20% total milk solids

Must weigh > 4.5 lb/gallon

Must contain > 1.6 lb Total Solids/gallon

Reduced Fat Ice Cream

25% reduction in fat content ( < 7.5% and > 3% milkfat)

Lowfat Ice Cream

3 g fat per serving (½ cup) (<3% milkfat)

Nonfat Ice Cream

½ g milkfat per serving (½ cup)

NLEA vs. Old Standards of Identity

Ice Cream Ingredients Water Milk-Solids-Not-Fat Butterfat Sweetener Emulsifier Stabilizer Flavorings Colors

Water

Milk-Solids-Not-Fat

Butterfat

Sweetener

Emulsifier

Stabilizer

Flavorings

Colors

The Freezing Process Scraped Surface Heat Exchange Batch Continuous Quality Attributes Ice crystal size Overrun Heat shock

Scraped Surface Heat Exchange

Batch

Continuous

Quality Attributes

Ice crystal size

Overrun

Heat shock