Lactic Souring

Production methods from starch to sugars.

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Uncle Jesse
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Lactic Souring

Post by Uncle Jesse »

Some information, rather lengthy.

From "The Alcohol Textbook", the chapter entitled Production of Scotch and Irish whiskies: their history and evolution. Scotch does not rely on lactic souring though as you'll see it's not as absent as people might guess.
Whisky worts usually have a specific gravity in the range 1.050-1.080, a pH value of around 5.0, a total acid content of 0.1% and an optical rotation of +30 degrees. After inoculation, the yeast content is 5-20 million cells/ml. The bacterial count varies with the cleanliness of the plant and the extent to which the raw materials were endowed with microbial flora. Scotch grain whisky fermentations create little if any foam because of their large content of suspended solids. However, in most Scotch malt whisky fermentations only a small proportion of the suspended solids in the mash is retained in the fermentation vessel. These fermentations tend to foam and the distillers have resorted to the use of various types of antifoams.

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Changes over the time course of a typical fermentation in a Scotch malt whisky distillery are depicted in Figure 6. Fermentation proceeds vigorously for the first 30 hrs, during which time the specific gravity falls to 1.000 or below and the optical rotation to around zero. The sugars in the wort are utilized in a particular sequence with glucose and fructose being fermented first, followed by maltose and then maltotriose. The removal of sugars during fermentation of a Scotch grain whisky mash is show in Figure 7 (Pyke, 1965). Over the first 30 hrs the pH value, after declining to around 4.2, rises to around 4.5. During the first 30 hrs the speicifc gravity drops at a rate of about 0.5 per hour accompanied by a massive evolution of heat. While many of the larger grain whisky distilleries have fermenters fitted with cooling coils, these coils are absent, or if fitted are relatively inefficient in most malt whisky distilleries where temperature can rise by the end of fermentation to as high as 35-37C. The distiller is concerned about the temperature rise during fermentation since this can cause the fermentation to stop or become 'stuck'. Temperature rise can be controlled by using a lower starting temperature or, because glycolysis of sugar is a heat-producing process, by using a lower initial concentration. Strains of Saccharomyces cerevisiae are well suited for malt whisky distillery fermentations since they can ferment efficiently over a wide temperature range. Fermentation is usually continued for at least 36 hrs and frequently longer, at which time the ethanol content of the wash is 7-11% (ABV). In larger distilleries, particularly those in the U.S., the carbon dioxide evolved is collected, liquefied and sold. Smaller distilleries, particularly the malt whisky distilleries in Scotland, usually do not have this facility.

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It should be noted that mashes in malt whisky distilleries are not boiled, so any enzyme activity manifested at the temperature of the mash and any microorganisms that can survive at that temperature will continue to be active during the fermentation. The continued activity of limit dextrinases in unboiled distillery mashes increases the concentration of sugars available for fermentation by the yeast. Hopkins and Wiener (1955) calculated that with amylases alone the yeast cannot metabolize the equivalent of the final 12-16% of the starch.

Another important consequence of using non-sterile conditions in distillery fermentations is the activity of bacteria that pass through in the mash, which are encouraged to some extent by the relatively high temperatures to which the fermentations can rise. In addition to lactic acid bacteria, the flora can include other Gram-positive as well as Gram-negative strains. The concentration of the flora depends on a number of factors including the extent to which the lactic acid bacteria grew during yeast propagation, the extent of the flora on the cereal raw materials and on the standard of hygiene in the distillery. There is no doubt, however, that the controlled activity of this bacterial flora, and particularly of the lactic acid bacteria, is accompanied by excretion of compounds that contribute to the organoleptic qualities of the final whisky (Geddes and Riffkin, 1989).

During the first 30 hrs or so of malt whisky fermentation there is vigorous fermentation and the majority of the aerobic bacteria die. This, however, provides ideal conditions for grown of anaerobic or microaerophilic bacteria, principally lactic acid bacteria (mainly strains of Lactobacillus brevis, L. fermenti and Streptococcus lactis) with the result that the concentration of lactic acid in the fermented mash can be as high as 30 mg/L (MacKenzie and Kenny, 1965.) A wide range of lactobacillus species have been identified in Scotch whisky fermentations including L. fermentum, L. brevis, L. delbrueckii, L. plantarum, L. casei and a bacterium resembling L. collinoides, in addition to Leuconostoc spp., Streptococcus lactis and Pediococcus cerevisiae (Bryan-Jones, 1976). More recently Barbour (1983) isolated many species that did not conform to recognized species of lactic acid bacteria, a point emphasized by Walker et al. (1990) who used DNA hybridization techniques to classify distillery bacteria. Growth of lactic acid bacteria is probably enhanced by yeast excretion of nitrogenous nutrients at the end of a vigorous fermentation. Kulka (1953) demonstrated the ideal nature of yeast autolysate for growth of lactobacilli. Bacterial activity in the fermenting wort also leads to removal of some acids. Actively growing yeast secrete citric and malic acids, but MacKenzie and Kenny (1965) attribute the lower concentrations of these acids in malt distillery worts (as compared to brewery worts) to their partial removal by bacteria.

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Occasionally, the extent of the bacterial flora in the fermenting wort can become too large. This causes problems due to sugar utilization by the bacteria that lead to an overall decrease in spirit yield. In addition, the bacteria may produce organoleptically-undesirable compounds and also release hydrogen ions causing the pH value of the wort to fall too low, thereby providing suboptimal conditions for action of certain enzymes. Examples of undesirable compounds that may be excreted by bacteria are hydrogen sulfide and other sulfur-containing compounds (Anderson et al., 1972). Lactobacilli can also metabolize glycerol (excreted by the yeast during fermentation) to produce B-hydroxypropionaldehyde, which subsequently breaks down on distillation to give acrolein (Harrison and Graham, 1970). Acrolein imparts a pungent, burnt and often peppery odor to the whisky (Lyons, 1974). In a later paper, Dolan (1976) concentrated on the problems arising in malt whisky distilleries when there is an unacceptably high concentration of bacteria in the mash. Table 3 shows changes in the concentrations of Gram-negative and Gram-positive bacteria and (separately) of lactobacilli during fermentation of a minimally-infected mash and of a heavily-infected mash. The time course of fermentation of an unacceptably-infected malt distillery mash (Figure 8 ) shows, in comparison with similar data for fermentation of an acceptable mash (Figure 6), a greater rise in the acid content of the mash after about 35 hrs and a lower optical rotation of the mash after about 40 hrs. In the fermentations there is often a difference of up to 4 hrs from the time a rise in the acid content is detected to the point when the pH value of the fermentation begins to fall. Dolan (1976) attributes this to the buffering capacity of the mash. The data in Table 4 show the effect of different levels of infection after 30 hrs fermentation of a malt distillery mash on spirit yield and the associated financial losses to the distiller. Dolan (1976) recommends upper limits of 1,500 bacteria, 50 Gram-positive and 10 lactic acid-producing bacteria per million yeast cells in the mash at the start of fermentation.

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Much less has been published on the effect of retaining solid material in the fermenting mash. However, marine microbiologists have long known that the presence of solid particles in a liquid medium can affect bacterial growth, probably because of the concentration of nutrients at the solid-liquid interface (Heukelekian and Heller, 1940; Zobell, 1943). Moreover, Cromwell and Guymon (1963) found that formation of higher alcohols during fermentation of grape juice is stimulated by the presence of grape skins or inert solids. Beech (1972) made similar observations on cider fermentations. Merritt (1967), in the only detailed report on the role of solids in whisky distillery fermentations, states that a dry solid concentration of 50mg/100 ml might typically be expected, although much will clearly depend on the design of the mash tuns used in individual distilleries. Merritt went on to report that a concentration of dry solids as low as 5 mg/100 ml causes an increase in yeast growth, and that solids also enhance the rate of production of ethanol and glycerol. There was also an effect on production of higher alcohols by the yeast (Table 5). With tth possible exception of n-propanol, production of all of the major higher alcohols was increased in the presence of solids, the effect being particularly noticeable with isobutanol and 2-methylbutanol.

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The effect of low insoluble solids content is a factor relevant to congener levels in malt whisky fermentations. In grain whisky production, where 'all-grains-in' fermentations are generally used, the degree of rectification during distillation is the principle determinant of higher alcohol levels in the spirit.
Next, info on a mash which relies on lactic souring - Rye whiskey.
Last edited by Uncle Jesse on Wed Mar 19, 2008 10:49 am, edited 1 time in total.
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pintoshine
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Post by pintoshine »

I really enjoyed this article. I can't wait for the the info on rye whiskey.
BW Redneck
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Post by BW Redneck »

Yes, nice article indeed. However, I do find something odd.
The Alcohol Textbook wrote:It should be noted that mashes in malt whisky distilleries are not boiled, so any enzyme activity manifested at the temperature of the mash and any microorganisms that can survive at that temperature will continue to be active during the fermentation.
Hmm. Their ingredients must be quite microbiologically clean. When I forgot to raise the temperature back up to 75 degC, my all wheat batch stank like a combination of dog shit and toe jam. I haven't ran it yet, so I don't yet know if it's a bad thing.

Can't wait for the next article. Very worthy of being in "research and theory" indeed! :D
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junkyard dawg
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Post by junkyard dawg »

stank like a combination of dog shit and toe jam. I haven't ran it yet, so I don't yet know if it's a bad thing.
dog shit and toe jam in the context of food and drink is rarely a good thing...

I been there... worst smell ever... what is that bug?
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Post by mtnwalker2 »

I look forward to the rye article also.

It was suggested to me, that rye grain naturaly had more good bacteria and yeast present than other grains, to make a sour dough starter. I have used that several time with fantastic results.
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Post by Harry »

Why wait? The chapters have been publicly available in my Library for almost 3 years.
http://distillers.tastylime.net/library/" onclick="window.open(this.href);return false;" rel="nofollow

Slainte!
regards Harry
================
news...

Saturday, 30th April 2005

1. Added four more chapters from "The Alcohol Textbook" by J. E. Murtagh. This will complete the offerings from this book. If you want more you'll have to buy it from a bookstore.

Ch 14 Production of American whiskies: bourbon, corn, rye and Tennesseeby R. Ralph



Ch 15 Production of Tequila from Agave by M. Cedeño Cruz and J. Alvarez-Jacobs



Ch 16 Production of Heavy and Light Rums by J. E. Murtagh



Ch 17 Fuel Ethanol Production by P.W. Madson and D.A. Monceaux

2. Added a nice Alcoholometer Correction Table by Geoff Redman which also shows calcs., graphs etc.

3. Added the Australian Distillation Act 1901 (2004). Essential reading for all Aussie distillers.



Wednesday, 27th April 2005

1. Added two smore chapters from "The Alcohol Textbook" by J. E. Murtagh.

Ch 12 Production of Canadian Rye Whisky by J.A. Morrison

Ch 13 Production of neutral spirits, preparation of gin and vodka by J. E. Murtagh



Tuesday, 26th April 2005

1. Added Column Designing & Costing by Andreas Linninger for the Chemical Engineers among us. Very technical calculations. 30 pages.

2. Added two selected chapters from "The Alcohol Textbook" by J. E. Murtagh, reputed to be the "Bible" for beverage distillers.

Ch 06 Molasses as a Feedstock by J. E. Murtagh

Ch 11 Production of Scotch and Irish Whiskies by T.P. Lyons
stoker
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Post by stoker »

hi Harry, welcome back.

<cut> (found on a russian forum)
Last edited by stoker on Tue Dec 18, 2007 8:09 am, edited 1 time in total.
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...

Post by Uncle Jesse »

well, plagiarizing an entire textbook isn't really my style...

more on rye soon
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Post by stoker »

and I follow the style of the admin :wink:
-I have too much blood in my alcohol system-
Uncle Jesse
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Post by Uncle Jesse »

The chapter on rye is very specific as to equipment and processes. Rye whiskey mashes are done in equipment which can agitate and heat to the point of pasteurization in order to minimize the lactobacillus present in the rye itself. Some excerpts:
The mashing or cooking of rye meal, like that of most other grains, is for the primary purpose of solubilizing carbohydrate components so they can be hydrolyzed to fermentable materials. The solubilization is a two-fold mechanism of hydration and gelatinization. The temperature range in which the processes take place most efficiently is specific for each grain starch used in a distillery (Table 3). Rye grain starch hydrates/gelatinizes over a range of 57 to 70C (MacLeod, 1977). Carbohydrate-hydrolyzing agents such as amylolytic enzymes will act very slowly if at all, on starch that has not undergone hydration and gelatinization.

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The gelatinization temperature range for rye starch is determined microscopically by observing the temperatures at which birefringence or double refraction of the initially crystalline starch granules begins to degrade and is then totally lost. Birefringence refers to the pattern of striations, or dark areas on starch granules, that appear when unheated crystalline starch solutions are viewed through a microscope using plane-polarized light. The birefringence pattern, in combination with the granular shape, is specific for each starch and can be used most effectively for the purpose of identifying starch origins. As the starch granule begins the process of gelatinization the granule swells, loses its crystal form and the birefringence gradually disappear.
When rye undergoes dispersion in heated water, much of the granule is gelatinized and therefore:
The swelling or gelatinizing of the granule and the subsequent starch dissipation will result in a substantial increase in the viscosity of the mash. If suitable liquefaction enzymes are not present, the viscosity will overload most mechanical mixing systems.
...
The gelatinization temperature of a rye grain starch is always exceeded in distillery cooking practice because the second purpose of mashing is sanitization of the mash as a means of microbial control during the fermentation stage. The higher mashing temperatures allow shorter exposure times to be effective for pasteurization and hence a more efficient mashing process is possible. A balance must be struck between using temperatures high enough to effect an efficient sanitization without destroying sensitive carbohydrates. The indigenous enzyme activity in rye meal may under certain cooker conditions produce significant quantities of low molecular weight sugars early in the mashing process. These will be susceptible to some degree of caramelization when exposed to high temperatures and will be lost as fermentables.
It goes on to discuss the fact that it's beneficial to use malt enzymes but that microbial amylases work as well.
Rye grain distilleries using batch cooking conduct the mashing in the following manner. Sufficient city water/recycled steam condensate is mixed with recycled backset (thin stillage) in a clean cooker to create a starting temperature of 30-35C, a pH of 5.8-6.0 and a calcium concentration of 75 ppm. On full agitation the cooker receives rye meal from a micro-processor controlled weighbelt or dropbin and the temperature is raised to 65C by live steam. The microprocessor programs the addition of thermostable A-amylase liquefying enzyme (such as Allcoholase I) at a rate of .05% of the grain weight and allows a hold of 10-30 minutes as required. The length of hold at this point will be determined by whether the viscosity of the mash is causing any impediment to mixing. The viscosity of the mash at this stage will depend on the level of intrinsic enzymes in the rye capable of extensive hydrolysis of the large starch, protein and gum molecules in the mash, if given sufficient time. If intrinsic enzymes are in short supply, quantities of B-glucanase enzyme (such as Allzyme) may be added at 65C and a 30 minute hold put into effect. This is done to lower the molecular weight of the glucan gums (polymers of glucose with B-type linkages) to at least the five glucose unit size.

Steam injection continues until the mash temperature is 85C and then a final gelatinization hold of 10 minutes is allowed. After cooling to 78C, a further addition of liquefying A-amylase enzyme is made at 0.05% of the grain weight. A 10-minute hold is taken and the mash is cooled to 70C. It is then pumped to a holding vessel for transfer through a cooler to the fermenters.

If the production schedule permits a longer mashing period, a final gelatinization hold at 80C for 20 minutes would suffice (instead of 85C for 10 minutes) with a net saving of steam and possibly a decrease in caramelization of low molecular weight sugars. It is certainly worthwhile to stay flexible and to experiment with different mashing techniques now that energy is a major cost item.
...
The agitation and high temperature will maintain the mash in a pasteurized condition until delivery to the fermenter system takes place. Failure to maintain good microbial control at this stage may result in significant lactobacillus contamination with the loss of sugar to lactic acid production. It is also considered good manufacturing practice to have some steam sparged into the holding vessel when empty as a further retardant to bacterial growth.
...
Into a clean fermenter (and thoroughly clean and constantly-steamed lines) sufficient backset stillage (usually 25% of total fermenter dilution) and wash water are combined with three or four cooker mashes (depending on fermenter size) and a 1.88% by volume yeast mash. The mash and backset are cooled to 35-38C by passing through banks of counter-flow pipe coolers. For open-top fermenters with less efficient cleaning, the backset may be acidified as a bacterial control measure. Additionally, the stillage-acid mixture may be used at high temperatures for continuous circulation through coolers and mash lines as a means of bacterial control when production delays occur. The combination of the heat, acid and grain solids in the mixture has an excellent souring action on the cooler and mash lines.

The yeast mash addition can be the liquid yeast mash produced as described later in this chapter, or it can be dried distillers yeast either in dry powder form or after reconstitution in a dilute mash for several hours...A yeast cell count of 250 million cells/ml is recommended for fermenter treatment for efficient conversion of the sugar to alcohol. The liquid dilution of the prepared yeast mash slurry is on the order of 70:1, so the fermenter should have an initial viable yeast count of approximately 3 million cells/ml.
Ok, so far it's been about cleanliness to keep lactic acid out of the picture, but rye does depend on lactic souring and here's how:
The lactic-yeasting operation at rye grain distilleries uses an all-rye grain mash slurry, which is pre-cooked at 65.6C for 30 minutes and then cooled to 53C. A small amount of thermolabile A-amylase enzyme is added for liquefication and the mash is then inoculated with a Lactobacillus delbreuckii culture and maintained at 53C for 9-11 hrs. Initially the lactobacillus inoculum may be grown from an American Type Culture slant incubated at 53C in sterilized rye. However, when the first culture has been grown satisfactorily on a plant scale, pails of the culture can be used as described below for future inoculation.

Rye meal can be used as a yeast mash slurry (unfortified by malt or other nutrients) as it meets the nutritional needs of the yeast. The cooking process promotes the release of starches and proteins from the meal, which in turn undergo conversion by the indigenous rye enzymes to smaller-sized carbohydrates and amino acids. This resultant mash is further converted and altered by the action of the lactobacillus incubation as described below to produce additional nutrients required by the yeast.

During the lactic incubation period the lactobacilli multiply and produce lactic acid, which in turn lowers the pH to about 3.6. A healthy propagation of lactobacilli will generate up to 0.9% lactic acid in the 9-11 hrs and the mash viscosity will be lowered appreciably. Plant process quality control includes periodic pH checks and the titration of a 100 ml mash sample with standard sodium hydroxide to monitor acid development. As inoculum for future use, pails containing 6 US gallons (22 liters) of the completed lactic incubation (with a minimum of 0.9% lactic acid) are collected. Pails are cooled to room temperature, treated with powdered calcium carbonate to raise the pH to 5.5 and quick-frozen in upright freezers.

The deliberate cultivation of a lactobacillus culture in the preparation of a yeast mash is good manufacturing practice with several benefits to the process. The selected temperature of incubation at 53C encourages certain high acid-producing bacteria to predominate in the mash and to produce sufficient lactic acid in 11 hrs to drop the pH to 3.6. Deviations from the 53C incubation temperature will decrease the purity of the population and the amount of lactic acid generated.

The time period and temperature of the lactobacillus incubation create an environment where bacterial spores are encouraged to metamorphose to a more easily-destroyed vegetative form prior to the final sterilization step. The lowered pH enhances sterility by creating an environment in which microbial proteins are made more susceptible to heat denaturation, which leads to the destruction of the organisms.

Finally, because of certain common biochemical pathways with yeast, the lactobacillus cultivation continues the conditioning of the rye mash by releasing certain growth factors that accelerate yeast growth. Presence of these growth factors, along with the nutrients in the rye mash, ensures healthy and prolific yeast cell growth.

On occasion, timetable or maintenance problems make it difficult to allow the yeast mash sufficient time for a proper lactic acid hold. The mash is therefore prepared and precooked in the same manner as before; but the pH is adjusted to around 3.6 with sulfuric acid. This method allows no time for any bacterial spores to vegetate and subsequently be destroyed during sterilization; so an acid mash may undergo bacterial growth of considerable magnitude during the yeast incubation stage. Additionally, the intermediate nutrients mentioned above will not be produced and cannot contribute to a healthy yeast growth. Thus, sulfuric acidification has the potential to produce inferior yeast inoculum for the fermenters. This method should be used only when all other options have been exhausted.

After acidification by lactic culture or sulfuric acid, the yeast mash is sterilized by heating to 121C for 1 hr. It is then cooled to 30C and treated with a small amount of thermolabile A-amylase at 79C and a saccharifying enzyme such as glucoamylase mash at 57C, and inoculated with large cans of Saccharomyces cerevisiae yeast culture. These large cans of yeast culture are prepared by standard propagation techniques from working yeast slants using a concentrated malt syrup as the medium. The inoculated yeast tub is incubated under controlled temperature conditions for 16-18 hrs with automatic agitation for 1 minute every 7.5 minutes. At the end of the 16-18 hr time period the yeast tub is cooled to 16C and allowed to remain at that temperature until needed in the fermenters. The yeast propagations are usually out of phase by about 12 hrs so that each yeast vessel may inoculate a series of fermenters with a minimum hold time.
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Post by wineo »

Great stuff jesse!I have a ferment going now with sour corn and rye lacto fermented,and I added amelaze to the lacto starter a few days before I added the whole 2 gallons of it to 23 pounds of mashed malt,wheat,rye that i didnt use a mash out on.It smells right,but I will have to see what kind of flavors I get from it.Im going to leave it alone after it quits for a week to give the lacto more time.Its being fermented cool at 63F.Its been working fine though.Its my first time trying to do the lacto,but the mash smells different.Very much good beer smell,with some sourness.We will see.
Keep up those articles!
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Re: Lactic Souring

Post by jsanders »

this is just a note, but in my reading here I decided to make UJSM. Later I read about letting corn mash sit for a few days, first day smells like puke, gets better 2d day due to other bacteria growning and killing puke bugs and so on. SO I have decided to try UJSM and let it sit open without yeast for 3 days then pitch the yeast. Any ideas? :D
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Re: Lactic Souring

Post by meangene »

Hi gents I'd like to post an observation on this subject. I have some experience with lactic acid fermentation with other foods (kimche) and it struck me that perhaps treating the corn to enhance the conditions for the lactic acid producing bacteria may hold true in this instance so I tried it. I soaked 1 lb of corn in a brine solution (1 cup salt per gallon) and just put another lb of corn in plain distilled water. After a 12 hour soak in the brine I rinsed the corn and covered it with water. After 72 hr the brine soaked corn was in a all out rolling fermentation with no puke smell. The control ( plain corn/water) was fermenting slowly and had a mold growth on top,this didn't smell so sweet either. Thats all I've done with it so far I'll check on it again this weekend.
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Re: Lactic Souring

Post by meangene »

Well it's a week later and both fermentations appear to be done. the brined corn has a sharp clean smell and a yellow fluid on top. The unbrined corn has a thin cap covering a yellow liquid with a cheese smell, while decidedly different it's not objectionable. I suspect that the early species of mold and bacteria may actualy add to the flavor profile as is the case with many other fermented foods. So I suppose after all this I really have no solid conclusion. Perhaps someone would be willing to try both methods in back to back runs and report on the flavor profile of the results.
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Re: Lactic Souring

Post by HookLine »

Thanks for this info.

Do you normally used distilled water for ferments?

Have you run the two ferments through the still? Separately?
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Re: Lactic Souring

Post by meangene »

Yes Hook I use distilled or boiled tap water for my bacterial ferments, I suppose there is no real need for distilled but it's my habit. No I haven't ran either this was just a small scale experiment. I do have a friend whom I may be able to talk into doing some experimental runs later this fall if so I will post a report.
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Re: Lactic Souring

Post by Nies »

Has anyone tried adding a lacto culture to their wort along with the yeast? I am curious because this method seems to give a lot of control to brewers over souring in beers. Could this also be of some value in a wash in order to obtain differing degrees of souring?
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Re: Lactic Souring

Post by trthskr4 »

Nies wrote:Has anyone tried adding a lacto culture to their wort along with the yeast? I am curious because this method seems to give a lot of control to brewers over souring in beers. Could this also be of some value in a wash in order to obtain differing degrees of souring?
Yes I have, I've tried several different methods. The bad thing is that I didn't take very good notes on the lactic souring projects. The yeast just seem to work along side the lactic process but the souring usually takes 7 days or so for me and the washes I make usually ferment dry in 3-5. Adding the lacto culture first 3 days earlier didn't seem to change my flavor profiles much but it did acidify the wash more than usual which wasn't a bad outcome. I've only done this on UJSM type ferments because, to be honest, all-grain is too much work to screw up a good cooking by experimenting and the normal results are just fine on their own IMHO.
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Nies
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Re: Lactic Souring

Post by Nies »

Trthsk4 wrote:Yes I have, I've tried several different methods. The bad thing is that I didn't take very good notes on the lactic souring projects. The yeast just seem to work along side the lactic process but the souring usually takes 7 days or so for me and the washes I make usually ferment dry in 3-5. Adding the lacto culture first 3 days earlier didn't seem to change my flavor profiles much but it did acidify the wash more than usual which wasn't a bad outcome. I've only done this on UJSM type ferments because, to be honest, all-grain is too much work to screw up a good cooking by experimenting and the normal results are just fine on their own IMHO.
So if a guy is willing to take the time, You could vary your souring base on that alone. This is good stuff. You see I like sour beverages , sour mash whiskeys, sour beers, its all good.
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Re: Lactic Souring

Post by Nightforce »

I guess I'm going to try a soured batch myself. I wasn't intending on a sour wash but the last corn/barley ferment I did seemed to kick off after the transfer to the better bottle. I thought it was just becuse it was cold in the garage and had warmed up enough to kick off the yeast again. Then I noticed a different cap forming, almost frothy, and gave it the ole sniff test. Sure enough, puke. I'll either run it for a sour run or run it in the bok for fire starter. LOL
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Re: Lactic Souring

Post by Midday Moon »

Has anyone tried the 53C inoculation temperature mentioned in the Alcohol Textbook? I've been getting the puke smell from my rye experiments. Though the taste is good after fermentation, and the smell seems to fade in subsequent steps, I'm wondering if I should be doing more with bacterial development. I'll probably try letting the mash sit for a few days before adding yeast next. Has anyone had success with this?

I wish I had an incubator...
Nightforce
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Re: Lactic Souring

Post by Nightforce »

I've been doing all grain lately and I've been having some issues with lactic souring myself. I've found that if I mix up a starter the night before, typically about a ¼ cup of sugar, a teaspoon of DAP (diammonium phosphate)and a pinch of Epsom salt in about ½-¾ quart of water with 2 packets of yeast (Red Star Premier Cuvee) and pitch that as soon as the temp. is down around 100-105°F the next day, it kicks off really quickly and the yeast seem to get ahead of the bacteria. I guess the alcohol kills off the bacteria; a good speedy ferment I think is key, just like the mentors on here state often. I guess they do know what they are talking about. hehehe.
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Re: Lactic Souring

Post by Bro-sephus »

I know this is a year old thread, but I've had some success in the last couple months using lacto soured field corn. The first batch I made I coverd my cracked field corn in double the water to the volume of corn and let it go for a week. Day two and three were gross, smelled like barf, but after day four the smell became sour but pleasant. First batch I mashed 6 lbs of lacto soured feed corn in about 3 ga of water (that it had soured in), boiling first to kill the nasties, then mashed at 155 with about 2 lbs of home malted wheat berries milled to flour. I got nervous and tossed in a couple pounds of refined cane sugar (as this was the first time I'd done almost all grains... :silent: ). After fermenting for a week using red star bakers yeast, I made some of my best likker yet. I kept it white and have been nursing it along for almost two months now!

My second batch, I soured the cracked field corn (about 9 lbs) for over a month, gelatinized around 155-160, and mashed with 3 lbs ground malted barley a good buddy gave me (thanks Joe!). I let it ferment aerobic for 24 hrs and it's been going anerobic for the last 6 hrs now. I'm really pleased so far with the lacto sour whiskey I've made, it's got a better, fuller flavor and it takes alot less time to gelatinize (this last batch gelatinized in 30 minutes).

Cheers,
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Re: Lactic Souring

Post by NcHooch »

meangene wrote:Hi gents I'd like to post an observation on this subject. I have some experience with lactic acid fermentation with other foods (kimche) and it struck me that perhaps treating the corn to enhance the conditions for the lactic acid producing bacteria may hold true in this instance so I tried it. I soaked 1 lb of corn in a brine solution (1 cup salt per gallon) and just put another lb of corn in plain distilled water. After a 12 hour soak in the brine I rinsed the corn and covered it with water. After 72 hr the brine soaked corn was in a all out rolling fermentation with no puke smell. The control ( plain corn/water) was fermenting slowly and had a mold growth on top,this didn't smell so sweet either. Thats all I've done with it so far I'll check on it again this weekend.
This one here has my attention ...
according to the OP, he soaked cracked corn in a brine solution for 12 hours, , then rinsed it, then covered with fresh water, and 3 days later he found it in an all-out rolling ferment with no puke smell.

Can I assume that the lacto performed the starch extraction and conversion,
and the yeast present on the corn was responsible for the ferment?

I'm gonna go back and read that article again, but sounds interesting.
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Re: Lactic Souring

Post by NcHooch »

I wanted to follow up on my prev post just so newbs didn't get led astray ...

near as I can tell,
a lactic fermentation doesn't produce alcohol, it produces acid (lactic), and C02.
Some lactics can produce alcohol, but it looks like they need sugars, as opposed to starches.
a lactic ferment can look just like a alcohol ferment, but usually doesn't smell the same.

I'll admit that I don't know a lot of details about this subject, but it seems pretty likely that some enzymes and yeast need to be intruduced the get the complete job done.

full report at 11:00 ;)
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Re: Lactic Souring

Post by NcHooch »

A week ago, I took 10 pounds for cracked corn and soaked it in 2 gallons of brine for 12 hours ..at that time I drained off the brine and rinsed the cracked corn ....then covered it with 5 gallons of fresh water .....it's been slowly bubbling for a week ...today, it smelled like an old corn siloh when I opened it ... Mrs Hooch said get it outa the house ! :problem:

So I tossed it in the BOP and fired up the propane burner ...I musta smelled up half the county heatin that corn ....did a 3-step cook and by the time I hit 200, it was really thick! ...
once it cooled to 150, I tossed in 3 pounds of crushed 6-row ...and that thinned it out a lot.

after it cooled to 110F, I poured 3.5 gallons each into 2 fermenter buckets and topped off each with 1.5 gallons of cold water...that dropped it to 90... pitched a packet of bakers yeast in each one.

Let the second ferment begin!

I tell ya what , if it dont smell better in a week, we might hafta write this one off. :lolno:
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Re: Lactic Souring

Post by NcHooch »

Turned out at the end of the ferment , it smelled just a little more sour than the usual Carolina bourbon ferment, so I ran it, and based upon the output, the conversion was good . I split the run into two and ended up with almost 2 quarts
of 80%
The hearts smell very nice (corn/barley) and are tasty too.
I'd judge it a success.
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Re: Lactic Souring

Post by pope »

Does anyone know from which text Uncle Jesse's post on rye mashing and lactic souring originated? I have the Alcohol Textbook (4th ed.), but can't find this section in the book. I'm wondering if it's from an older edition of the book, as the 5th edition wasn't published until after his post was made. I'm interested in getting a copy of the text if it's from a different book.

The 4th edition has a fairly short write-up on lactic souring, not mentioning any bacterial strain specifically, but generally stating that small grains, rye and malted barley [although wheat seems acceptable as well], are used for yeasting. The yeasting batch is cooked separately and the pH is adjusted to 3.8 with lactic acid bacteria, with a sterilizing 30-minute boil prior to fermenting the yeasting mash, which is shown to be 1/10th the volume of the final mash. The yeasting mash is then fermented from 22 degrees Plato to 11 before pitching into the main mash. The text specifically states that corn is not used for a yeast mash because it doesn't contain the growth factors required for yeast and lactic bacteria growth. The text refers to the yeasting tub as a dona tank.

I have a packet of Lactobacillus Delbrueckii culture on order, and I'll be reporting back after I've employed it to lower the pH per both the processes I've outlined above and the notes posted by Uncle Jesse on working with rye and lactic souring.
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Re: Lactic Souring

Post by Prairiepiss »

You can download the 4th edition online. If you look for it. I think you can even read it in Google books. I don't have it with me so I can't tell you if its in there. But you mite as well look through it anyway.
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Re: Lactic Souring

Post by pope »

I can't say that I've read the entire book, but I do have it in pdf format and have queried several key terms and phrases from the quotes on the rye/lactic and haven't found it. I couldn't find a single use of the term (species) 'delbreuckii/delbrueckii'. Anyway the diction certainly sounds like it's from the same book, and some of the scotch whiskey information matches up from the second of Uncle Jesse's posts, so I assume it's just an older edition. I just find it interesting that if it is from the same book, how much information has changed between editions - a lot of what he has included on rye mashing and lactic souring seems to have been dropped from the 4th edition altogether, and it just makes me wonder what other gems of knowledge didn't get carried forward. The TOC for the 5th edition suggests there are a few new chapters in there as well. Sorry for getting a little off-topic.
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