Final notes

Animal tissues vary widely in…

Moisture content, protein content, fat content, pigmentation, ability to bind fat and water

bind or binding

water tension capabilities of lean meat or surface cohesion of meat cuchkns binding to each other. In sausage batters it includes both water tension and fat stabilization.

A low binding ability in meat is because of …

high in fat content, connective tissues, or smooth muscle

ex. tounge, giblets, esophagus, hanging teder

A high binging ability in meat is because of ….

it is high in myofibular proteins

ex. cow/bull meat, beef chucks, pork shoulder, lean pork (80%), poultry meat (no skin)

Intermediate binding…

have more fat and connective tissues

ex. cheeck and head meat, beef falnks and shanks, pork (50%), briskets, hearts, jowls

filler meat binding ability….

high in connective tissues, smmoth muscle, dont have lots of skeletal muscle

ex. lips,livers, skin, tripe, snouts

How heating and cooling effect binding…

during cooking the collagen will shrink and take up water, but as it continues to cook collagen will denature and loses its water binding ability and fat particles melt and are least stable. once it cools the collagen will gelatinize, but contributes very little to fat stabilization and over all structure of the cooked sausage.

moisture:

accounts for 45-60% of finished weight of processed mear products

reasons for adding water to products

\-many would be dry and unpalatable, if moisture only came from meat products

\-improve tenderness and juiciness of products

\-ice keeps down temp. during comminution step

\-water serves as a carrier for distributing curing ingredients, especially in non-comminuted meat such as hams and backs

\-improves yield of finished products

why extenders

\-improve meat batter stability

\-improve water binding capacity

\-enhance texture or flavor

\-reduce shrinkage during cooking

\-improve slicing characteristics

\-reduce formulation costs

extenders commonly used in sausage

whey and soy

seasonings

a general term applied to any ingredients added to improve or modify flavor in processed meat products

Antioxidants

limited to certain types of fresh and precooked sausage, dry sausage, and dried meats

types of casings

Natural and manufactured

advantages of natural casings

\-preamble to moisture and smoke

\-shrink and remain in close contact to surface of product

\-digestible and can be eaten

\-impart resistance to chewing

four classes of manufactured casings

Cellulose, inedible collagen, edible collagen, plastic

cellulose casing

Advantages - easy to use, variety in sizes, uniformity of size, strong, low microbial load

disadvantages- not digestible

Inedible collagen casing

combines advantages of cellulose and natural, strength and uniformity, it shrinks

Edible collagen casing

used for fresh breakfast sausage links

Plastic

Impermeable to smoke and moisture, protection against oxidative changes and the growth of acrobial organisms

restructured meat products

raw material lack tenderness without particle size and reduction, acceptable tenderness as well as texture resembling intact cuts

The objective of restructuring it to produce exudates on all meat surfaces that will “set” as a gel and bind pieces together prior and during heating

\-salt and phosphate to extract proteins

\-finally chopped meat batters and sometimes non-meat products are added to preform the binding function

heat processing

65-77 degrees Celsius

heat processing results

\-pasteurize the product, kill most of the microbes

\-firm up and set the structure, develops as a result of protein transformation. salt-soluble proteins undergo heat induced gelatin

\-develop and fix cured meat pigment, by developing reducing conditions and denaturation of nitric oxide myoglobin

Smoking

the process of exposing products to wood smoke at some point during processing

smoking results

\-develop specific flavors and improve appearance

\-some preservative effect, bacteriostatic or bacterialoiciadat and antioxidant properties

fermentation

microbial fermentation (lactic acid producing bacteria) results in a distinct tangy flavor. usually from a stater culture to provide uniformity

dehydration and aging

drying (preserve product) reducing water content males a product shelf stable. aging in for proper cure development, two textural changes during drying and aging, more tender firmer and harder due to loss of moisture

purposes for such holder

\-flavor development

\-textural changes

\-complete various curing reactions

\-dry and harden the product

Deterioration during storage and handling caused by…

\-microorganisms (bacteria, mold, yeast)

\-insects

\-endogenous enzymes

\-exogenous enzymes

\-chemical reactants

\-physical effects (freezer burn or drip)

sources of contamination

\- non-streial knifes

\-hides,feet,manure,and viscera

\-equipment ,clothing,hands

\-water, air, walls

lag phase

1st

cells increase in size

Logarithmic phase

2nd

increase in number of microorganisms

Stationary phase

3rd

rate of growth slows and becomes constant

death phase

4th

destruction of microorganisms

Extrinsic factors

\-temp.

\-relative humidity

\-presence/absence of oxygen

\-physical form of meat

psychrophiles

temp. lower than 20

thermophiles

temp. higher than 45

mesophiles

temp. between the two, 20-45

aerobic organisms

require oxygen to grow

anaerobic organisms

grow in the absence of oxygen

Facultative organisms

grow with or without oxygen

physical state

Communication creates a problem, larger areas of exposed surfaces, more readily available water and nutrients for bacteria, greater oxygen penetration and availability, chopping and mixing can distribute bacteria throughout the entire production

Intrinsic factors

\-moisture content

\-pH

\-oxidation reduction potential

\-nutrients available

\-presence/absences of inhibitory substances

PSE

microbial growth is reduced (lower pH)

DFD

very susceptible to microbial growth (high pH)

SSOP

Sanitary standard operating procedures

HACCP

hazard analysis critical control point

pre-operational sanitation steps

\- dry cleaning

\-detergent foam

\-hot water rinse

\-sanitizer

Personal

hair coverings, clean clothing, hand washing

Equipment

cleaned during breaks

slaughter procedures

minimize animal content , especially once hide is removed, procedures covering hides and evisceration

Trimming

all visible contamination must be trimmed, preffered over washing because of water spray

Organic acid

reduces pH and kills bacteria on surface, 1-2% solution lactic acid or acetic acid

steam pasteurization

steam vacuum or steam cabinet

irradiation

cuts or other meat products

Characterization of spoiled meat

equated with decomposition and purification resulting from microbes. not due solely from microbial action, but also factors line intristic infection and intrictic enzyme and oxidative reaction

chemical changes

Digression of proteins lipids and carbs into simplified versions, is accomplished by action of endogenous hydrolytic enzymes present in meat as well as enzymes produced by microbes

physical changes

\-color

\-odor

\-flavor

\-tenderness

\-processing properties

aerobic spoilage

bacteria and yeast usually result in slime, unstandable odors, flavors, and color changes. molds result in sticky surfaces. limited to meat surfaces

Anaerobic spoilage

occurs in meat interiors, vaccum packaged products, or seald containers, sours or taints caused by anaerobic bacteria that may have been present in lymph nodes, bone, joints, or may have gained entrance along bones during storage and processing

oxidative rancidity

polyunstaurated fatty acids including phospholipids are more susceptable to auto oxidation than monostaurated or saturated fatty acid. rate of auto oxidation us enhanced by pro-oxidants= NaCl, some metal ions, heat, UV light, low pH, ect.

discoloration

usually due to the presence of metmyoglobin. brown color dentection when 60% of myoglobin is in the metmybolin form

dehydration

surface discoloration because of loss of moisture and concentration of pigments and loss of intracellular water reducing light reflection

Shrinkage

due to moisture loss-economic loss

absorption of off-flavors

aromartic compounds from other foods, such as, apples, onions , are readily absorbed by meat tissues

Freezer burn or drip

excessive loss of moisture from surface of meat resulting in localized areas of dehydration and discoloration

Acceptability is affected by…

\-appearance

\-purchase price

\-aroma during cooking

\-cooking loss

\-ease of preparation for serving

\-edible portion

\-tenderness

\-juiceness

\-flavor

\-perceived nutrient value

Raw color

consumers expect attractive color

dark-lack of freshness, animals could be older or under long term stress

fat- consumers desire creamy white , yellow fat (less appealing )

cooked color

brown surface-crispness and unique flavor

interior color influences palatability depending on desired doneness

cooked texture

imparts sensory in persons related to adhesions, mealiness, or fragmentation. overcooked meat is stringy in appearance and associated with previous experience with dryness and lock of flavor

muscles, bone, and fat

affects appearance and palatability

Perception of tenderness

\-softness of the tongue and cheek

\-resistance to teeth pressure

\-ease of fragmentation

\-mealiness

\-adhesion

\-reside after chewing

major components of tenderness, three groups

connective , muscle, and adipose tissue

connective tissue

Background effect

associated with animal age, muscle location, and sex class

increase in collagen and increase in permanent crosslinks, all are associated with tenderness

muscle fiber structure

\-actomyosin effect

\-contractile state

\-fermentation of cross-bridges occurs in the absence of shortening during rigor mortis

\-during aging calpains cause degreation of myofibrillar structures and loss of z-discs leads to an increase in fragmentation

three theories of marbling level and tenderness interact

\-bite theory, fat is less dense than muscle

\-lubrication theory, produce more saliva so perceived as more tender

\-insurance theory, meat is juicer and perceived as more tender

Marbling

Enhance juiciness indirectly. melted fat becomes translocated along the preimysical connective tissue. uniform distribution may act as a barrier to moisurte loss during cooking

water

Because fat free water content is relatively uniform, differences in juiciness relate primarily to the ability of muscle to retain water during cooking . aged meat is juicer than unaged

flavor and aroma

stimulates saliva and gastric juices, aid in digestion

Perception of flavor

bitter, sweet, salty, sour, umami

temp.

both cooking and endpoint temp. have a greater influence on palatability than marbling

cooking losses

increase in cooking and endpoint temp. , increase in cook loss, degrease in juiciness, and decrease in flavor

protein hardening

induced by cooking at high temp., decrease in tenderness

collagen solubilization

when meat is cooked rapidly , not enough time for collagen solubilization to occur

effects of heat on meat color

external color is a combination of dehydration and sugar amine brewing reactions, brewing occurs at readitivly high temps. (90).

internal color progessive loss of redness with increasing temp. results from progress denaturation of pigments

effects of heat on meat texture

muscles may appear soft, hard, course, or smooth

adipose tissue may appear soft or crisp

effects of heat on meats structural

loos of native structure of protein under goes several changes in confermation , denaturtiation, accomplished by aggration or clumping or coogulation

effects of heat on meats myofibrillar proteins

fiber microstructure is recognized after heating but disintreagtion of filimens and unltimently z-disks, occurs progressivly at higher temp.

effects of heat on meats collagen

physical shortening of the fiber to 1/3 of the orginal length. after cooling it will gelatinize

effects of heat on meats tenderness

heat causes both tenderness and toughing of meat

very rare

56-58

rare to medium rare

62-64

Medium

72-74

effect of heat on meats juiciness

the greater the degree of doneness the less juicy the meat will be

effect of heat on meats flavor and aroma

certain voliatlie materials are driven off during cooking, that contribute to the unique flavor and aroma

dry heat

surround the meat with hot dry air , appropriate for tender cuts of meat, because heating period is for a short amount of time and there is moderate time to achieve connective tissue hydrolysis

moist heat

Extra liquid during cooking , recommended for cuts with relatively lager amounts of connective tissues. the liquid provides all the water necessary for complete hydrolysis of collagen. low temps. over a long period of time all for conversion of connective tissue without protein hardening

microwave

heating occurs from conversion of microwave energy to heat by friction faster than conventional methods, some varying in doneness and textural properties. NOT recommended for less tender cuts. it is recommended for processed meats

carving

allow to stand for a few minutes, allow it to remain more juiciness, carry over cooking, and firmer and easier to carve. cut perpendicular to grain