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Lactobacillus

731 bytes added, 14:35, 29 May 2015
added somepitching rate info
===General Advice===
----====Cell Growth====''"I typically grow it by itself anaerobically in [http://www.neogen.com/Acumedia/pdf/ProdInfo/7406_PI.pdf MRS media]. Seems to work very well and results in good growth. I've personally had the best success with MRS media and in an anaerobic environment, though I know some lactobacillus strains grow aerobically just fine. The problem with growing lactic acid bacteria is the acid they produce will eventually inhibit their own growth. MRS contains a buffer to help combat the drop in pH as a result of LAB metabolism, which keeps the pH around 6-6.5 (I think) for optimal growth. I usually grow them at 35 C, but sometimes incubator space is at a premium (like right now) and I just spin it on the benchtop!"''<ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1031115430250004/?comment_id=1031228363572044&offset=0&total_comments=24 Conversation with Nick Impellitteri on Milk The Funk Facebook group. 3/5/2015.]</ref>. ~ Nick Impellitteri from [[The Yeast Bay]] on general Lactobacillus cell growth''':
''"I typically grow it by itself anaerobically in [http://www.neogen.com/Acumedia/pdf/ProdInfo/7406_PI.pdf MRS media]. Seems to work very well and results in good growth. I've personally had the best success with MRS media and in an anaerobic environment, though I know some lactobacillus strains grow aerobically just fine. The problem with growing lactic acid bacteria is the acid they produce will eventually inhibit their own growth. MRS contains a buffer to help combat the drop in pH as a result of LAB metabolism, which keeps the pH around 6-6.5 (I think) for optimal growth. I usually grow them at 35 C, but sometimes incubator space is at a premium (like right now) and I just spin it on the benchtop!"'' <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1031115430250004/?comment_id=1031228363572044&offset=0&total_comments=24 Conversation with Nick Impellitteri on Milk The Funk Facebook group. 3/5/2015.]</ref>.----'''Bryan Heit of [http://suigenerisbrewing.blogspot.com/ Sui Generis Brewing blog] on Lactobacillus and =Hop Tolerance''':====''"There is a fair bit of research into hop tolerance out there; its not a simple topic as a number of factors come into play to produce hop tolerance. To make things even more complicated, hop tolerance is an inducable trait in many lacto species - meaning that a seemingly susceptible strain can become resistant by culturing in ever-increasing doses, and a seemingly resistant strain can become susceptible after a generation or four in a hop-free media. ''~ Bryan Heit of [http://suigenerisbrewing.blogspot.com/ Sui Generis Brewing blog] on Lactobacillus and Hop Tolerance
''Edit: I tried to add (but facebooks aversion to white space almost defeated me) that I've been trying to generate a permanently high-alpha acid resistant lacto strain for a few months now. I've been culturing L. brevis in escalating IBU wort (starting at 10, currently at 25). Every 4th generation (1 generation = a subculture of a stationary-phase lacto culture, not as in # cell divisions) I pass it through 2 generations of an IBU-free media to try and select for strains which maintain this resistance. This seems to have worked upto ~18 IBU, but past that point the resistance appears to remain inducable. I'm hoping a few more generations will provide me with a permanently tolerant strain.''
''I'm hoping to have a blog post on that sometime in the next few months, but life is nuts right now so I offer no guarantee."'' <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1002795743081973/?comment_id=1003625646332316&offset=0&total_comments=16&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with Bryan Heit on Milk The Funk. 01/19/2015.]</ref>
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'''Bryan Heit of [http://suigenerisbrewing.blogspot.com/ Sui Generis Brewing blog] on storing dried Lactobacillus, such as probiotics or [[Dry Yeast for Sour Ales BlackManYeast]]''':
====Storage of Dry Lactobacillus====
''"Yes, refrigerate them. In the lab course I run we compare probiotics stored at room temp versus in the fridge - viable bacterial numbers dip off ~80x faster in non-refrigerated samples."''
And in regards to liquid cultures and storage:
''"I'm not sure about the liquid cultures - I freeze mine at -80°C (lab freezer), which (stores) indefinitely. As a rule refrigerated liquid cultures should last longer... but there is anecdotal evidence (for some species) of poorer survival of refrigerated versus room temp in liquid cultures. IMO, stable temps are likely more important for non-frozen stocks than hitting an 'ideal' temperature."'' <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1067614393266774/ Conversation with Bryan Heit on Milk The Funk. 05/04/2015.]</ref>~ Bryan Heit of [http://suigenerisbrewing.blogspot.com/ Sui Generis Brewing blog] on storing dried Lactobacillus, such as probiotics or [[Dry Yeast for Sour Ales BlackManYeast]] ====Pitching Rates====(In progress)Pitching 1 liter per 5 gallons, or 1 gallon per barrel of beer, of Lactobacillus starter is the general guideline <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1077639885597558/?comment_id=1080061532022060&offset=0&total_comments=11&comment_tracking=%7B%22tn%22%3A%22R0%22%7D Conversation on MTF. 5/29/2015.]</ref>. Exact pitching rates can be difficult to achieve due to the small size of bacteria <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1068323126529234/?comment_id=1068337639861116&offset=0&total_comments=47&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation on MTF with Bryan Heit. 5/6/2015.]</ref>.
== Commercially available Lactobacillus strains and their pH change over time ==
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