GINGER BUG - BEER Natural-wild fermentation of ginger in water
Ginger bug soda is essentially a ginger beer, made from ginger, water and sugar, that is wild fermented. Ginger bug can also refer to the culture itself. Natural bacteria (usually lactic acid bacteria) and wild yeasts on the ginger consume the added sugar and produce fermentation byproducts. The liquid is filtered from the solids producing a beverage or beer. Many fermentation epicureans refer to this as probiotic, but it may or may not be. Not all lactic acid bacteria are probiotic.
HACCP Category: Food Code 3-502.11 Special Process - Ginger bug is a wild yeast/lactic acid bacterial fermentation of ginger, sugar, and water. With yeast present, it may contain alcohol and possibly ≥ 0.5 ABV if the starting level of sugar is high.
Ingredients: ginger, water, sugar and optionally: fruit, fruit juice, or spices.
- Ginger "bug". Mix 2 tablespoons chopped ginger (skin included), 2 tablespoons sugar and 2 cups water in a mason jar or container.
- Cover loosely or fit with an airlock to let gas to escape. Leave at ambient temperature.
- Each day, for several days, stir in 1 additional tablespoon of chopped ginger and 1 tablespoon sugar.
- Ferment until the pH ≤ 4.6. Refrigerate the "bug" culture to use within a week or so.
- Ginger soda beer. Start with fruit juice or tea with sugar. Add 1/4 cup ginger bug culture to 1 quart of "soda beer" mixture.
- Ferment at ambient temperature until the pH ≤ 4.6 or lower as desired.
- Package. Note: if residual sugar is left in excess in the soda beer, it will ferment inside sealed containers leading to over-pressure and seal failure or worse.
The culture is often referred to as "ginger bug" presumably because these are the "bugs" from a wild fermentation of ginger. The exact combination of bacteria and yeasts will always vary and will likely contain yeasts and bacteria. The desired bacteria to grow are the lactic acid bacteria. As a wild culture the lactics will be from both LAB groups (homo- and hetero- fermentative). To ensure consistency and absence of pathogens, a *commercial source for your ginger bug is desired. Wild or natural cultures may contain pathogens. *none available known to the author.
Dairy kefir ingredients before fermentation are considered a Temperature Control for Safety Food (TCS food). Water kefir with sugar alone is TCS. The addition of fruit before fermentation may reduce the pH ≤ 4.2 resulting in it no longer being TCS.
GInger bug is generally considered to be safe due to the lack of evidence of foodborne illness events related to it. Properly fermented ginger bug (pH ≤ 4.5) inhibits many pathogens, but not Escherichia coli, Listeria monocytogenes, and Salmonella spp. These pathogens may grow very slowly or just survive. Care therefore must be taken in the fermentation of ginger bug to prevent the access or growth of these microorganisms. There are no pasteurization or heating steps.
- Vegetative bacteria (e.g. E. coli O157, Listeria moncytogenes, Salmonella, and similar). Vibrio and Campylobacter are not expected in these types of foods.
- Vegetative bacteria that produce toxins (Staphylococcus aureus)
- Sporeforming bacteria that produce toxins (Clostridium botulinum, C. perfringens, and Bacillus cereus). B. cereus is associated with outbreaks in starches and grains.
The food safety of flavoring ingredients, fruits, fruit juices, or spices must be assessed when they are added after the fermentation step (generally right before bottling or packaging).
CCP1: Pasteurize all of the ingredients except for the fermentation of ginger ≥ 145°F for 30 minutes or ≥ 161°F immediately). This will destroy all of the vegetative pathogens that might be present.
CCP2: Ferment RAPIDLY with an active culture to get the Ginger bug pH ≤ 5 and optionally ≤ 4.2. At pH ≤ 5 with refrigeration, no pathogen can grow. At any temperature and pH ≤ 4.6 C. botulinum cannot grow and at pH ≤ 4.2 no foodborne illness bacteria can grow.
CCP3: Ginger bug that has a pH > 4.2 must be refrigerated ≤ 41F. SOP: Ginger bug with a pH ≤ 4.2 should be refrigerated to minimize continued fermentation (quality).