Natural and wild wine processes, or wine processes that relate to mixed fermentation brewing.
- 1 Wine Making Processes
- 2 Biochemistry
- 3 Beer and Wine Hybrids
- 4 Comparisons to Mixed Fermentation Beer
- 5 See Also
- 6 References
Wine Making Processes
- "Carbonic Maceration: Art of Nouveau" by Erika Szymanski, November 18, 2010. See also related MTF thread.
- "Whole bunches and stems in red winemaking" by Jamie Goode.
See the Cider page.
- "Understanding Difficult Malolactic Fermentations" by Dr. Molly Kelly, Enology Extension Educator, Department of Food Science.
Lactic Acid Bacteria
Lactobacillus plantarum has been found to produce 3-sulfanylhexan-1-ol (3SH) from precursors in wine (3SH-S-cys and 3SH-S-cysgly) at a more efficient rate than wine yeast. 3SH is a volatile thiol that has a grapefruit-like flavor and aroma and is considered to be an important flavor component of some wines . 50 ppm of total SO2 can inhibit the growth of lactic acid bacteria in finished wine , although some species/strains require between 100-256 mg/L total SO2 in order to be inhibited (see Pediococcus) .
Lactic acid bacteria are often suppressed by yeast fermentation, which is caused in part by the yeast consuming nutrients. Very low levels of alcohol (1.5%) have been shown to stimulate early growth of LAB, but growth and MLF begin to become inhibited around 6% ABV. Yeast produce SO2, which can also inhibit LAB. However, other studies have suggested that alcohol, SO2, and low nutrients are not the only suppressors to LAB. Studies have also shown that there can be an antagonistic relationship between O. oeni and Pediococcus in wine, which may be due to toxins produced by one that affects the other known as "bacteriocins". Bacteriocins have been proposed to winemakers by scientists as a way to reduce the populations of unwanted lactic acid bacteria, although further research is needed to perfect this approach to winemaking .
The pH of the wine can have an impact on which lactic acid bacteria species will grow. Below a pH of 3.5, O. oeni is the most dominant LAB species. Lactobacillus and Pediococcus are more common in wines above a pH of 3.5, with Pediococcus being most common in wines with a pH between 3.8 and 4.0, although Pediococcus has also been found in wines with a pH as low as 3.2 .
Biogenic amines are produced by all living things and are present in many fermented beverages. High dosages can lead to health issues such as vomiting, headache, asthma, hypotension, and cardiac palpitation. Thus, biogenic amines have been studied intensely . For more information, see "Fact or Fiction – Biogenic Amines in Beer" by Dr. Bryan Heit.
- Biogenic amines in spontaneously fermented beer.
- Biogenic amine production in Pediococcus.
- Biogenic amine production in Brettanomyces.
Beer and Wine Hybrids
Legal limits of Must in Beer
Advice from James Howat of Black Project Spontaneous Ales on how much must can be added to beer legally for commercial brewers: contact the TTB and your local state government to present your formula and find out how much must is allowed. The state law may not match with the TTB law. Once they answer, ask for the code for the law for your records .
- Barrel fermented porter with 100 lbs of Cabernet Sauvignon grapes with stems, fermented with red wine yeast (BM45) and B. bruxellensis by Dara McMains on MTF. More tips on using Brettanomyces in wine from Dara McMains here and 100% fermented B. claussenii wine from Malvasia, Petite Manseng and Viognier grapes.
- Using northern climate cold hardy varietals with a lot of malic acid (Frontenac, Frontenac gris, etc.), and selecting bacteria for malolactic fermentation.
Threads on using wine pomace:
Threads on harvesting yeast from wine grapes:
- Harvesting yeast from hybrid Regent and Cabernet Jura grapes, and a sub-thread on the validity of the term "natural wines".
Comparisons to Mixed Fermentation Beer
- Dara McMains on the leather quality of Bordeaux, Chateauneuf du Pape, old vine Cabernet Sauvignon especially.
Additional Articles on MTF Wiki
- Impact of Lactobacillus plantarum on thiol precursor biotransformation leading to production of 3-sulfanylhexan-1-ol. Hideki Takasea, Kanako Sasakib, Daiki Kiyomichib, Hironori Kobayashia, Hironori Matsuoa, Ryoji Takatab. 2018. Doi: https://doi.org/10.1016/j.foodchem.2018.03.116.
- Dr. Molly Kelly. "Understanding Difficult Malolactic Fermentations". Wine & Grapes U. 10/26/2018. Retrieved 11/22/2018.
- Role of Pediococcus in winemaking. M.E. Wade, M.T. Strickland, J.P. Osborn, C.G. Edwards. 2018. DOI: https://doi.org/10.1111/ajgw.12366.
- James Howat. Milk The Funk Facebook group on how much wine must can legally be added to beer. 09/16/2017.