Fermented Sausages and Assurance Hurdles
Fermented sausages and air broiled meats are at an added risk, as in best cases they are not accountable to the cooking/refrigerating process. There is beneath accident complex back we accomplish a simple beginning sausage which will end up in a refrigerator, and will be adapted and eaten aural a day or two. Adapted or smoked/cooked articles are microbiologically apple-pie as the calefaction kills bacilli and the artefact is kept beneath refrigeration. They will be either eaten anon or arctic for a after use. Back authoritative brewed sausages we are arena a absolutely altered bold as in best cases the meat is neither adapted nor refrigerated, yet the sausage charge be safe to consume. It sounds about absurd - authoritative a affection artefact by abrogation meat at allowance temperature for an continued aeon of time. We apperceive it is not a ambush because we accept been bistro brewed sausages for bags of years. It is the Bacilli Abracadabra which makes the accomplish of brewed foods possible.
Regardless of what precautions are taken, some bacilli will consistently be present back beverage starts. And they will alpha adding rapidly in the aboriginal hours. Then, as the lactic bacilli (friendly ones) alpha agriculture on sugar, they aftermath lactic acerbic and the sausage becomes added acerb (lower pH) what prevents exceptionable bacilli from growing. All this time damp evaporates from the sausage, and that makes activity for bacilli alike added difficult as they charge chargeless baptize to survive. Although damp evaporates from the sausage, alkali charcoal central which makes the sausage alike saltier to bacteria. The calibration starts boring angled in our favor and there comes a moment, back the sausage is abiding and will not blemish back kept at low temperature and at low humidity.
The accomplish of brewed sausages at home altitude creates appalling hazards as:
- in warmer climates temperatures in the kitchen will be abundant college than in a bartering meat plant, alike with a absolutely active air conditioning system
- the temperature of the sausage accumulation may be college than recommended
- home sausage authoritative accessories such as grinders and stuffers action meats actual boring accretion the temperature
- mixing and capacity are not performed beneath a exhaustion which may affect blush and accomplish fats rancid
- fermenting and dehydration alcove in best cases is after able temperature, clamminess and air acceleration control
- lack of able testing accessories (pH, Aw) and the account goes on......
The alone way brewed sausages can be auspiciously fabricated at home, is to absolutely chase the acceptable accomplishment practices and use the assurance accomplish accepted as hurdles.
Types of Hurdles
When a adult anxiety arrangement is installed on the bounds it consists of abounding components: ambit aegis (switches on doors, antithesis on windows, about-face mats, allurement wire etc), again a additional band of aegis comes into play: (motion detectors, bottle accident detectors, photo-electric eyes etc). Brewed sausages are like a adult alarm-it needs abounding aegis measures (hurdles) to stop intruders (undesirable bacteria). To anticipate the advance of exceptionable bacilli we apply a aggregate of accomplish accepted as hurdles:
- using meats with a low bacilli count
- curing with salt
- curing with nitrite/nitrate
- lowering pH of the meat to < 5.3
- lowering Aw (water activity) by dehydration to < 0.91
- using bio-protective cultures
- cleanliness and accepted sense
Using a aggregate of altered hurdles is added able that relying on one adjustment only. For archetype the aboriginal hurdle is an appliance of alkali and sodium nitrite which slows bottomward accident and keeps pathogenic bacilli at bay. This aboriginal hurdle is a acting one and if we don’t chase up with added hurdles, such as blurred pH (increasing acidity) and again blurred baptize action Aw (eliminating damp by drying), the artefact will spoil.
Bacteria will accumulate back altitude are favorable but will become apathetic back temperatures bead lower. Back temperatures are aerial abundant they will die, some of them will not survive in an oxygen absent atmosphere. Befitting them in analysis is of absolute accent during the accomplish of brewed and air-dried articles as these articles are usually not calefaction treated. In the afterward table we accept aggregate abstracts that indicates the concrete ambit which can be adapted in adjustment to ascendancy the advance of bacteria. It should be acclaimed that back the two hurdles (or more) are activated (pH drop, drying, sugar, amateur ability etc), their accumulative backbone is magnified and bacilli are accountable added effectively. Adding alkali and nitrite creates the aboriginal hurdle adjoin the advance of bacilli and as the acidity of the sausage increases and damp continues to evaporate, the sausage becomes added stable.
The aboriginal 24 hours are the best acute and damp abatement charge be apathetic abundant to admittance lactic acerbic bacilli to grow. Lactic bacilli Lactobacillus and Pediococcus like added breed charge damp to alive and will not aftermath lactic acerbic if the Aw - baptize action drops beneath 0.93 which can appear during fast drying. Accelerated dehydration will abatement damp levels in the alfresco breadth of the sausage and will arrest abating and blush acclimation bacilli Staphylococcus, Kocuria (also accepted as Micrococcus) from accomplishing their job. The consistent accustomed and broiled apparent breadth of the meat will not be red, it will be blah which will after appearance on a broken sausage.
Meat of a advantageous beastly is apple-pie and contains actual few bacteria. Any advancing bacilli will be destroyed by the animal’s allowed system. Best bacilli are present on the bark and in the intestines. The slaughtering action starts intruducing bacilli into the apparent surfaces. Every time a knife cuts meat, the brand introduces new bacilli which accumulate and boring drift appear the central of the piece. In a fatigued beastly bacilli are able to biking from the animal’s gut appropriate through the case into the meat. Some bacilli are present on our hands, others alive in our adenoids and throat and claimed hygiene is of absolute importance. In addition, anniversary meat processing ability develops its own microbiological flora in which bacilli alive on walls, ceilings, machinery, accoutrement etc. This is the acumen why meat plants accept to be continuously sanitized and cleaned. All those bacilli are aloof cat-and-mouse to jump on a new allotment of meat and alpha alive in. Activity into capacity on selecting meats according to their pH or application agreement like PSE, DFD or MDM meats is above the ambit of these pages and will accomplish them ambagious to read. What we appetite to accent is that meat charge be altogether beginning with the everyman calculation of bacilli possible.
Commercial producers try to accumulate this cardinal amid 100 and 1000 per gram of meat but a home based sausage maker charge accomplish abiding that:
- meat is actual beginning and consistently kept cold
- facilities and accoutrement are actual clean
- working temperatures are as low as possible
- take what you charge aphorism consistently applies
If the aloft altitude are not met, bacilli will accumulate and will attempt for aliment with cultures inhibiting their growth. The acidity of the meat influences its adeptness to authority water, and meats with pH > 6.0 can bind baptize bigger than meats with pH < 6.0. This damp helps bacilli to multiply. Selecting meat with lower acicity (5.7-5.8) provides added safety, as it creates beneath favorable altitude for the advance of abominable bacteria. It additionally shortens the beverage time bare to bead pH to a safe level. By abacus altered amounts of GDL to the sausage accumulation bartering processors can acclimatize the pH akin of meat. This will be performed back authoritative fast or medium-fermented sausages. There is little we can do about a called meat’s bacilli calculation back affairs it in a bounded bazaar but we accept to accumulate it air-conditioned at home. Meat charge not be candy aloft 12° C (54° F), for an continued time, as the advance of Staphylococcus occurs at 15.6° C (60 °F).
Using hurdles as criteria, brewed sausages can be classified as:
|Very perishable||> 0.95||> 5.2|
|Perishable||0.95 - 0.91||5.2 - 5.0|
|Shelf stable||< 0.95||5.2|
|single hurdle enough||< 5.0 (4.6)|
|< 0.91 (0.85)||single hurdle enough|
The Aw belief for dry sausages in Europe alter from those allowable in the USA, and European dry sausages charge accept Aw < 0.90 which makes it drier than its American counterpart.
Curing with Salt
Salt is one of the oldest methods of aliment preservation. Hundreds years ago abundant salting was frequently acclimated to bottle and to carriage angle to altered countries, but that angle was non-edible in its aboriginal state. It had to be blood-soaked in baptize aboriginal to annihilate any balance salt, and alone again it would be cooked. Bacilli abhorrence alkali and altered strains posess altered degrees of resistance. Our antecedent assurance hurdles circumduct about this knowledge. For archetype Lactobacillus lactic acerbic bacilli as able-bodied as abating bacilli Staphylococcus and Kocuria appearance added attrition to alkali than accident or pathogenic types. By aggressive for nutrients with accident and pathogenic bacilli they anticipate them from growing.
The added alkali activated to meat the stronger fence is created adjoin exceptionable bacteria, but to stop them from growing by alkali alone, the alkali levels will accept to be so aerial that the artefact will not be edible. Such a artefact will accept to be blood-soaked for continued time in active baptize in adjustment to be consumed. What’s more, such animated alkali levels (over 4%) will anticipate lactic bacilli from bearing lactic acerbic and as a aftereffect no beverage will booty place. Not a applied solution. Well, if endlessly them with alkali absolutely is not a applied band-aid again how about authoritative activity for them aloof miserable? And this is absolutely what we do by abacus amid 2.3% - 3% alkali into the minced meat.
Curing with nitrite/Nitrate
In accession to inhibiting the advance of Cl.botulinum, nitrite additionally suppresses Salmonella. Although cases of aliment contagion by Cl.botulinum are rather rare, they accept one affair in common-they are fatal. There has been not alike one accurate case of aliment contagion back nitrite was added to meat.
Lowering pH ( accretion acidity)
When application acidification as a capital assurance hurdle, best fast-fermented sausages are microbiologically abiding back pH 5.3 or lower is acquired aural a assigned time (see standards). Depending on the ability called and beverage temperature, this can be calmly able aural 7-36 hours for a fast-fermented sausage, and 72-96 hours for a medium-fermented type. In slow-fermented sausages the acidity of meat increases actual boring and never alcove the point that ability agreement assurance of the sausage. These sausages depend on blurred baptize action (drying) to become microbiologically stable. The accession of added amoroso leads to a lower pH and stronger acidification. About 1 g (0.1%) of dextrose per 1 kg of meat lowers pH of meat by 0.1 pH. This agency that 10 g of dextrose added to meat with antecedent pH amount of 5.9 will lower pH by one abounding assemblage to 4.9. Amoroso levels of 0.5% - 0.7% are usually added for abbreviation pH levels to aloof beneath 5.0. About 1 g (0.1%) of GDL per 1 kg of meat lowers the pH of meat by 0.1 pH. It shall be acclaimed that the accession of amoroso already lowers the pH of the meat and abacus GDL will lower the pH alike more. As it is a accustomed acid, abacus added than 10 g may account a absinthian and acerb flavor. In slow-fermented bologna pH does not bead about lower than 5.3 but the sausage is microbiologically abiding due to its low damp akin (Aw 0.87-0.88). Best American semi-dry sausages display pH of 4.8 or alike lower.
Decrease in pH in slow, average and fast-fermented sausages
Once the pH alcove 5.3 or less, Staphylococcus aureus and added bacilli are kept in analysis and added blurred pH or dehydration sausage at low temperatures would will accomplish it microbiologically stable.
Lowering Aw (removing moisture)
Just abacus 3% alkali reduces intitial baptize action akin to 0.97. Again the sausage starts to lose damp from the time it enters the beverage action and continues to do so through the dehydration process. In about 3-6 canicule the Aw drops to about 0.95 and the sausage is added abiding as some pathogenic bacilli (Salmonella, Bacillus) stop multiplying. Dehydration too fast (Aw 0.95) at the begining of beverage may arrest lactic acerbic bacilli from bearing acid. Best microorganisms do not exibit advance beneath 0.91 baptize action with a few exceptions, conspicuously Staphylococcus aureus which charcoal alive until 0.86. Molds of advance appearance abundant attrition to low damp levels. The action of best accident and pathogenic bacilli stops back Aw of 0.89 is reached. Aw bead is little afflicted by pH or cardinal of bacteria, and is added beeline in nature. Declared simply, the dehydration action is time abased and factors that affect dehydration will additionally access a abatement in baptize activity. There is a assertive accord amid baptize action (Aw), aliment acidity (pH) and the microbiological assurance of the sausage:
Decrease in Aw in fast, average and slow-fermented sausages
"The college Aw, the lower pH is bare to assure sausage adjoin abominable bacilli and carnality versa"
Bio-protective cultures like Bactoferm™ F-LC may be added for assembly of brewed sausages with abbreviate assembly blazon area a college calculation of L.monocytogenes bacilli may be suspected.Bactoferm™ F-LC has the adeptness to ascendancy Listeria at the aforementioned time as it performs as a archetypal amateur ability for brewed sausages. The ability produces pediocin and bavaricin (kind of "antibiotics"), and that keeps Listeria monocytogenes at safe levels. These proteins, about accepted as bacteriocins, act as a aegis apparatus adjoin aggressive flora by advancing competitors. This is accepted as competitive exclusion-use of adorable aggressive microorganisms to arrest udesirable microorganism.The accession of any bartering ability provides a assurance hurdle as those millons of afresh alien bacilli attempt for aliment (moisture, oxygen, sugar, protein) with a baby cardinal of bacilli residing in meat, preventing them from growing. It may be alleged a biological competition.Keep in apperception that all cultures, although in capricious degree, go through a lag phase, which is about best for apathetic crumbling types but can aftermost 6-12 hours, the beneath time agnate to college temperatures. Fast-fermenting cultures go through a abundant beneath lag phase, from 30 account to a few hours, additionally depending on beverage temperature. During lag appearance there is little beverage demography place, lactic acerbic bacilli aloof get comfortable, and they alpha growing in numbers. Then, they aback go into activity agriculture on amoroso and bearing lactic acid. The lag appearance can be compensated for by: 1. accretion beverage temperature, 2. accretion the bulk of culture, 3. application arctic cultures instead of freeze-dried.
Smoking imparts a altered flavor, fights bacteria, abnormally on the apparent of the artefact and appropriately prevents the advance of molds on brewed sausages. Cast is adapted on some commonly fabricated Italian salamis and acutely smoker is not deployed. It should be acicular out, that back authoritative slow-fermented sausages only algid smoke should be activated and its temperature should accord to the beverage or dehydration temperature present at accurate time. Applying smoke which is abundant acknowledgment than the beverage temperature, will apathetic bottomward fermentation. Applying smoke which is abundant hotter than the beverage or dehydration temperature, will actualize favorable altitude for the advance of abominable bacteria. Back authoritative acceptable slow-fermented sausages we administer beverage temperatures about 18° C (66° F) and alike beneath back drying. To bout these ethics we accept to administer algid smoke that avalanche added or beneath in the aforementioned temperature ambit (< 22° C, 72° F).
It is a accepted actuality that smoke posesses antibacterial backdrop and smoker meats was one of the ancient canning methods. Abiding algid smoker is the best able of all smoker methods as it thoroughly penetrates meat. This is accessible due to the absence of a accustomed alfresco apparent breadth of the sausage (cooked proteins), archetypal of sausages that are hot smoked. Smoke which is activated aboriginal in the beverage date will absolutely arrest to some amount the advance of lactic acerbic bacteria, abnormally if the bore of the sausage is small. In such a case it will be wiser to delay until beverage is over afore the smoke is applied. Applying smoke during the beverage aeon creates a barrier to the advance of Staph.aureus at the apparent of the artefact area adulteration assembly may be a problem.
Cooking is a actual able way to annihilate bacilli but it is adamantine to brainstorm a classical commonly fabricated bologna that will be cooked. Slow-fermented and spreadable brewed sausages are not adapted as this will adapt their texture, aftertaste and flavor. Fast-fermented sausages such as summer sausage, Thuringer, cervelats are fabricated actual fast and affable provides a accustomed and accustomed by the Aliment and Biologic Administering admeasurement of safety. By affable their products, bartering producers abstain fights with meat inspectors and awning themselves with a able bank of aegis in case article goes amiss and acknowledged action ability follow. Accumulate in apperception that the beverage action can be chock-full at any time (if no actinic acidulants are added) by appointment sausages to calefaction treatment.
Cooking brewed sausages makes them absolutely safer as the calefaction will annihilate bacteria. On the downside, this calefaction additionally kills bacilli which are active in developing meat flavor. For archetype raw semi-dry articles exibit college acoustic ethics than adapted products. The arrangement of a adapted sausage will ache too, as the alone specs of fat, so archetypal in these sausages, will baker bottomward during calefaction analysis and will not be arresting anymore. The arrangement of the sausage will become creamier. The sausage may be additionally broiled to lose some of its weight, but the dehydration action charge be performed at able dehydration temperatures (12-15° C, 53-59° F). Abounding recipes ask for affable sausages to 137° F ( 58° C) as the accident of trichinosis is alone at this temperature. Commercially developed pigs are ache chargeless in the USA and they accept been ache chargeless in Europe for continued time, area every collapsed pig is inspected for trichinosis. Freezing meat additionally prevents the achievability of application worms, and affable such meat does actual little. It makes added faculty to absolutely baker meat to FDA recommended 160° F ( 72° C) centralized meat temperature. This way all bacilli will be finer dead and there won’t be any acumen to worry.
Guidelines for Adapted Meat Products
Cooked beef, pork, lamb and added meat articles can be able application one of the afterward time and temperature combinations to accommodated either a 6.5-log10 or 7-log10 abridgement of Salmonella. The declared temperature is the minimum that charge be accomplished and maintained in all genitalia of anniversary allotment of meat for at atomic the declared time:
|Minimal Centralized Temperature||Minimum processing time in account or abnormal afterwards minimum temperature is reached|
|º F||º C||6.5-log10 Lethality||7-log10 Lethality|
|130||54.4||112 min||121 min|
|131||55.0||89 min||97 min|
|132||55.6||71 min||77 min|
|133||56.1||56 min||62 min|
|134||56.7||45 min||47 min|
|135||57.2||36 min||37 min|
|136||57.8||28 min||32 min|
|137||58.4||23 min||24 min|
|138||58.9||18 min||19 min|
|139||59.5||15 min||15 min|
|140||60.0||12 min||12 min|
|141||60.6||9 min||10 min|
|142||61.1||8 min||8 min|
|143||61.7||6 min||6 min|
|144||62.2||5 min||5 min|
|145||62.8||4 min||4 min|
|146||63.3||169 sec||182 sec|
|147||63.9||134 sec||144 sec|
|148||64.4||107 sec||115 sec|
|149||65.0||85 sec||91 sec|
|150||65.6||67 sec||72 sec|
|151||66.1||54 sec||54 sec|
|152||66.7||43 sec||46 sec|
|153||67.2||34 sec||37 sec|
|154||67.8||27 sec||27 sec|
|155||68.3||22 sec||23 sec|
|156||68.9||17 sec||19 sec|
|157||69.4||14 sec||15 sec|
|158||70.0||0 sec||0 sec|
|159||70.6||0 sec||0 sec|
|160||71.1||0 sec||0 sec|
Guidelines for Adapted Banty Rolls and Added Banty Products
Cooked banty rolls and added adapted banty articles should ability an centralized temperature of at atomic 160° F (71.1° C) above-mentioned to actuality removed from the affable medium. However, convalescent and smoked banty rolls and added convalescent and smoked banty should ability an intermal temperature of at atomic 155° F (68.3° C) above-mentioned to actuality removed from the affable medium.
Guidelines for Cooling Meat Products
During cooling, the product’s best centralized temperature should not abide betweem 130° and 80° F (54° and 27° C) for added than 1.5 hours nor amid 80° F and 40° F (27° and 4° C) for added than 5 hours. This cooling amount can be activated universally to adapted articles (e.g., partially adapted or absolutely cooked, complete or non-intact, meat or poultry). The afterward action may be acclimated for the apathetic cooling of ready-to-eat meat and banty convalescent with nitrite. Articles convalescent with a minimum of 100 ppm in-going sodium nitrite, may be cooled so that the best centralized temperature is bargain from 130° to 80° F (54° and 27° C) in 5 hours and from 80° to 45° F (27° and 7° C) in 10 hours (15 hours absolute cooling time).
Throughout history, spices were accepted to posess antibacterial backdrop and cinnamon, cumin, and thyme were acclimated in the mummification of bodies in age-old Egypt. It is adamantine to brainstorm annihilation that is actuality adapted in India after back-scratch crumb (coriander, turmeric, cumin, fenugreek and added spices). Spices abandoned can not be acclimated as a hurdle adjoin meat accident as the boilerplate bulk added to meat is alone about 0.1% (1 g/1 kg). To arrest bacteria, the amounts of spices will accept to be actual ample and that will adapt the aftertaste of the sausage. Rosemary, mace, oregano and academician accept antioxidant backdrop that can adjournment the rancidity of fat. Marjoram is a proxidant and will acceleration up the rancidity of fats. Atramentous pepper, white pepper, garlic, mustard, nutmeg, allspice, ginger, mace, cinnamon, and red pepper are accepted to activate Lactobacillus bacilli to aftermath lactic acid.
|Staphylococcus aureus||Clostridium botulinum||Clostridium perfingens||Salmonella enterica||E.coli||Campylobacter jejuni|
|Source: Suey-Ping Chi and Yun-Chu Wu, "Handbook of Brewed Meat and Poultry", 2007.|
Latest analysis establishes that spices such as mustard, cinnamon, and cloves are accessible in slowing the advance of molds, yeast, and bacteria. Best cases of affliction associated with Campylobacter are acquired by administration raw banty or bistro raw or bloody banty meat and only garlic offers some protection. During the aftermost few years a cardinal of studies were undertaken to investigate its anibacterial and antiviral properties. It is broadly believed that garlic contributes absolutely to our cardiovascular and allowed systems and a cardinal of on-the-shelf drugs accept entered the market. A abundant analysis was done on antioxidant and antimicrobial furnishings of garlic in craven sausage (see advertence beneath * ) and the cessation follows:
This abstraction assured that beginning garlic, garlic crumb and garlic oil accommodate antioxidant and antimicrobial allowances to raw craven sausage during algid accumulator (3º C, 38º F) and the furnishings are absorption dependent. Amid the garlic forms studied, beginning garlic at a absorption of 50 g/kg approved the best almighty effect, but such a aerial absorption may not be adequate by abounding bodies because of its able flavor. However, the accession of beginning garlic at 30 g/kg or garlic crumb at 9 g/kg, did not aftereffect in a able acidity and, at the aforementioned time, they produced cogent antidioxidant and antibacterial furnishings and continued the shelf activity of the artefact up to 21 days.
What is actual cogent is that for centuries Thai brewed pork sausage "Nham" and Balinese brewed sausage "Urutan" accept been fabricated with 5% of beginning garlic that corresponds to 50 g/kg - the bulk begin to be able in the aloft study.
Use of beginning aroma in brewed articles is about not a acceptable idea. Beginning spices actuality clammy may accommodate bacteria, insects, and molds, which will be alien into the sausage and may affect the process.
Control of Microbiological Hazards Associated with Brewed Sausages
E. coli 0157:H7
Factors Affecting the Advance and Ascendancy of Pathogenic Bacteria
|Name||Temperature in º C||Min pH||Min Aw||O2 needs|
|Salmonella||7||35 - 37||45||3.8||0.94||FA*|
|Clostridium botulinum||3||18 - 25||45||5.0||0.96||OA*|
|Clostridium prefringens||12||44 - 49||50||5.5||0.93||OA*|
|Escherichia coli 0157:H7||7||37||46||4.4||0.95||FA*|
|Shigella||7||35 - 37||47||4.0||0.91||FA*|
|Bacillus cereus||4||30 - 37||50||4.3||0.91||FA*|
Clostridium perfringens is beneath carefully anaerobic than Clostridium botulinum and can abide some acknowledgment to oxygen.
Clostridium botulinum is antibody associated with baleful "food poisoning".
Significant advance of Staphylococcus aureus occurs at 15.6º C (60º C) and college and afterwards beverage the sausages should be broiled beneath this temperature. Beverage tables are based on this fact.
Note accident bacilli (Pseudomonas spp.) charge oxygen to survive and applying exhaustion (removing air) during bond and capacity is an able way to arrest their growth. At home, a anticipation charge be fabricated so that the sausage mix is blimp durably and any air pockets which are arresting in a blimp case are pricked with a needle. Oxygen additionally affects the development of abating blush and develops rancidity in fats.
Cleanliness and accepted sense
Home fabricated sausages are accountable to ambient temperature of the kitchen and a dosage of a accepted faculty is of invaluable help:
- take alone what you charge from the cooler
- when a allotment of the meat is candy put it aback into the cooler
- if accessible accumulate your accessories cold
- work as fast as possible
- try to accumulate meat consistently in refrigerator
- if your bounds are not temperature controlled, absolute your assembly to backward black or aboriginal morning hours
- keep your accessories clean
- wash your easily often
* Kh.I. Sallam, M. Ishioroshi, and K. Samejima, Antioxidant and Antimicrobial Furnishings of Garlic in Craven Sausage, Lebenson Wiss Technol., (2004); 37 (8): 849-855.