Curing Flashcards
Addition to meats of some combination of salt, sugar, nitrite, or nitrate for preservation, color, and flavoring
Curing
Curing
Production of thermally stable meat pigment and cured meat flavor by the action of sodium nitrite, NaCl, sugar, and other cure ingredients
Curing is synonymous with
Pickling, infusing, marinating
Principle of curing
Small amount of nitrite (dry salt or salt solution in water) reacts with the muscle pigment, myoglobin.
NaNO2 + myoglobin =
Distinct cured meat color
Nitrosomyoglobin
Salt
Helps in dehydrating food
Imparts flavor
Sugar
Added to lessen the hardness of the straight-cure process
Makes the product more appetizing
To provide energy for the nitrate-reducing bacteria
Ascorbates
Na ascorbate (0.1 - 0.2% of meat weight)
Stabilizes pigments
Facilitate rxns of nitrite with myoglobin
Has the ability to react with the red meat pigment (myoglobin) to produce the heat-stable red curing color
Sodium nitrite
According to the Codex Alimentarius (1991), the max ingoing amount for processed meat products is normally up tp
200 mg/kg of product
Nitrite concentration should be
Equal or less than 0.02%
Residual level of nitrite upon reaction with myoglobin
50-100 ppm
True or false. Traces of nitrite are poisonous and should not be in food.
False
A curing salt usually used
Prague powder no. 1
Prague powder no. 2
Prague powder no. 1
6.25% sodium nitrite
93.75% table salt
True or false. Sodium nitrite is available in the market.
False.
True or false. Almost all nitrite will react with myoglobin
False. Half
Nitrite is also inherently present in
Vegetables
Prague powder no. 1 is used for
Sausages and corned beef
Prague powder no. 2
6.75% NaNO2
4.00% NaNO3
89.25% NaCl
Prague powder no. 2 is usually used for
Meats that require longer cures, hard salami and ham
Salt petre
Na or K NO3
Salt petre is used for
Dry cured products: raw hams, require long curing and aging periods
In salt petre, nitrate must be
Broken down by bacteria to nitrite
Beneficial properties of nitrite
To create a heat-resistant red color — makes cured product more attractive to customers
Inhibits bacteria growth (C. botulinum)
Attributes a specific desirable curing flavor
Stabilizes of fats and retards rancidity (antioxidant effect)
True or false. Nitrites always form nitrosamines.
False. Under certain conditions only.
Under certain conditions, nitrites form
Nitrosamines
Nitrosamines are
Carcinogenic substances found in strongly cooked or fried meats that were cured with nitrite
What curing ingredients reduce nitrosamine levels?
Effective
- Sodium erythorbate
- Sodium ascorbate
Concentration-dependent
- NaCl
Curing agents used
NaNO3
NaNO2
Color development reaction
Nitrate is reduced by bacteria to nitrite
Nitrite is chemically reduced to nitric oxide (NO)
NO + H —> HNO (nitrous acid)
HNO + myoglobin (at pH 5.4 - 6.8 - induced by ascorbic acid) —> nitrosomyoglobin
Light pink: typical color of cured meat
Nitrosohemochrome
Bright red: typical fresh meat color
Oxymyoglobin
Purple red: freshly cut surface
Myoglobin
Dark red
Nitrosomyoglobin
Brown color of meat
Metmyoglobin
Gray-brown cooked meat color
Denatured metmyoglobin
pH needed to react HNO with myoglobin
5.4-6.8
2 methods of curing
Dry curing
Wet curing
Dry curing
Curing ingredient is directly rubbed on meat
Dry curing uses…
Dry salting
Periodic rearrangement or rotation of meat piles (equalize drippings)
Advantages and disadvantages of dry curing
Advantages
- relatively high priced specialty products are produced
- less perishable because of their dryness and firmness
- more flavor
Disadvantages
- high cost due to poor space utilization and amount of labor required
- high inventory due to slowness of curing
- harsh salty favor
Wet curing
Curing mixture is dissolved in water and applied by soaking the meat or injefting the solution
Other terms for wet curing
Brine curing and pickling
Advantage and disadvantages of wet curing
A
- less harsh flavor
D:
- poor utilization of space
- slow turnover of meat inventories
Curing brine is injected into the muscle tissue
Curing brine injection
How does curing brine injection accelerate the curing process?
Curing solution reacts immediately with the myoglobin inside the tissues.
Curing brine injection is used for
Pork
- hams and picnic shoulders
Beef
- briskets
Thermal or hot cures
Heat is applied during the curing process
Problems in curing
Spoilage
Incomplete color development
Nitrite burn
Color fading during storage
Souring, putrefaction, tainting
Mold or yeast growth
Spoilage
Souring, putrefaction, tainting
Mold or yeast growth
green color and bad smell
pink/white spots, slimy
Excess and/or uneven application of nitrite
Nitrite burn
Effect of oxidation in nitrite burns
Dark, undesirable color
Incomplete development of color ratio
Nitrite:metmyoglobin ratio
5:1
True or false. Adding more nitrite during incomplete color development will achieve desired color.
False. Will not be useful; food color
Smoking and UV light
Color fading during storage
Nitrite-free meat products
Color -
Antioxidant -
Flavor -
Antibacterial
Color - PCCMP or CCMP - red blood cells of animals
Antioxidant - BHA, STPP, TBHQ - prevent lipid oxidation
Flavor - synthesized cured meat flavor
Antibacterial- not necessary - sorbic acid, K salts, lactic acid, propylparabens
Nitrate from vegetable sources is reduced to nitrite by what microorganism?
Staphylococcus carnosus
Examples of starter cultures
Celery powder
Sugar-vinegar blends
Natural nitrate sources
Celery juice
Cherry powder
Swiss chard
Carcinogen Classification
Red meat
Processed meat
Red meat
- group 2A
- probably carcinogenic
- limited evidence
Processed meat
- group 1
- carcinogenic
- Sufficient evidence
What type of cancer are identified to may have/have positive associations with the consumption of red meats/processed meats?
Colorectal cancer
Is eating processed meat as dangerous as tobacco smoking or exposure to asbestos?
No.
What organization has classified cured meat as carcinogenic? What was their advice?
WHO
Moderate consumption to reduce risk of cancer
Aside from cancer, high cured meat consumption also leads to
Higher risk of COPD
Worsening of asthma symptoms over time
Risks increases with the
Amount of meat consumed
True or false. There is no established safe level of cured meat consumption.
True.
50 g of meat eaten daily increases the risk of colorectal cancer by
18%
