EVERYTHING YOU NEED TO KNOW ABOUT YOGURT STARTER CULTURE
Posted on June 01 2018
The living cultures in yogurt are called beneficial bacteria because they support digestion and are nourishing.
When beneficial bacteria are taken to improve health, they are considered ‘probiotics’. Essentially yogurt is the product of these beneficial bacteria fermenting milk and turning it into an acidic food that will stay consumable longer than milk itself. In the process, the milk becomes a kind of medicine teeming with millions of gut loving bacteria.
There are different ways to add bacteria culture. You can use a portion of pre-made yogurt, a specific blend of dried bacteria, or a probiotic powder. I go into each in more detail below.
TRADITIONAL ANIMAL MILK YOGURT FERMENTATION
A traditional yogurt starter is a carefully balanced blend of bacteria which consume the lactose in animal milk. These bacteria convert the lactose to lactic acid, which changes the protein structure of the milk, creating a unique tangy taste and a thicker, creamier texture. And here's why you should make real yogurt at home.
Animal milk yogurt is produced using a starter culture made up of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. Lactobacilli and bifidobacteria may also be added.
Yogurt starter cultures are carefully balanced so that the strains work together, but different combinations of these bacteria produce different types of yogurt. A country or region is often known for a specific blend. Depending on the fermentation and time the characteristic tangy flavor of homemade yogurt can range from mildly sour to very tart, plus the texture can vary from drinkable to thick set.
There are other factors also - The type and quality of animal milk you use also impacts the texture. Goat milk yogurt and raw milk yogurt will be runnier than pasteurised cow milk yogurt. Yogurt starter culture can also be used to ferment cream.
NON-DAIRY MILK YOGURT FERMENTATION
In dairy-based yogurt the bacteria in a starter culture feed on the milk’s natural sugar, (lactose) during fermentation. Alternative, non-dairy milk doesn’t have as much natural sugar available to feed the bacteria and ensure the culturing process will take place or continue for the full duration of the fermentation.
Adding a little bit of sugar is enough to aid fermentation and proliferate the bacteria strains. It might seem wrong and naughty but I recommend white sugar. Remember it’s not for you, it is for the bacteria! Healthier sweeteners, such as honey or maple syrup are really not the best food source for bacteria.
There are no specific strains of bacteria required for making non-dairy yogurt. Any combination of sugar loving bacteria, from either a yogurt starter culture or a probiotic capsule or powder will repopulate if the conditions are right. The only 3 things they need are food (a little bit of sugar), warmth and time. But, always follow the directions and use the exact amount specified.
FREEZE-DRIED BACTERIA STARTER CULTURE
If you Google ‘yogurt starter culture’ you will find many varieties to choose from. All of them will contain a combination of bacteria that will make yogurt in both dairy and alternative milks. While yogurt starter cultures can vary in taste and consistency, the one you select ultimately depends on your personal preferences. Unless you have a specific dietary concern that requires eliminating or repopulating a specific species of bacteria, you can confidently buy any yogurt starter culture on the market. It’s really that simple. Click over to our comprehensive list of GAPS & SCD starter cultures and where to buy them.
It is essential that you follow the directions and use the amount specified. It may be tempting to add more starter culture to your yogurt in an attempt to increase the probiotic content, but this can negatively affect the texture and consistency and possibly spoil your yogurt.
DAIRY FREE YOGURT STARTER CULTURE
Most yogurt starters are grown in dairy milk, so if you are vegan or have a dairy allergy, you can buy a starter culture that has been grown in a non-dairy medium.
YOGURT AS A STARTER CULTURE
Using a quantity of existing yogurt is a common way to inoculate milk for a new batch of yogurt. When purchasing commercial yogurts look at the ingredients list and make sure it contains live cultures and does not contain any flavours or additives. Plain Greek yogurt is the best choice.
Furthermore, homemade SCD yogurt can also be used as a starter for another batch. Simply reserve ½ a cup to inoculate the milk. Over time the probiotic strains will weaken so this is not a process to be repeated indefinitely.
Commercial, non-dairy yogurt will contain stabilisers and gelling agents that will interfere with the yogurt culturing process. It is advisable to always use a dried bacteria starter culture or probiotic with non-dairy milk.
PROBIOTIC POWDER AS A STARTER CULTURE
The bacteria in a probiotic pill or powder will multiply in yogurt, however if you are making dairy milk yogurt not all probiotic bacteria will result in true yogurt. In order to make set yogurt, instead of a probiotic drink, the probiotics must contain one of these strains; Lactobacillus bulgaricus, Streprococcus thermophilus, Bifidobacterium lactis or Lactobacillus acidophilus.
It is best to use a premium, multi-strain probiotic that requires refrigeration. Speak to your Naturopath or Pharmacist for a good quality, practitioner brand. Where dairy is a concern, look for brands labelled as ‘dairy-free’ or ‘vegan’.
Probiotics may come as a powder or capsule. To use as a yogurt starter culture, simply add the required dose or open the capsule and pour the contents into your milk. One dose or capsule is enough for 4 cups of milk.
SCD YOGURT STARTER CULTURE
The original Specific Carbohydrate Diet (SCD), from the book ‘Breaking the Vicious Cycle’, calls for a yogurt starter that does not contain Bifidus/Bifidum bacteria because it can ‘take over’ and cause health problems in some cases. While on the early stages of the diet it is best to avoid anything that has 'bifid' in its name. e.g. Bifidobacterium infantis, Bifidobacterium bifidum, Lactobacillus Bifidus, Bifidobacterium longum etc. Click here for a list of SCD friendly starter cultures and commercial yogurt options for making SCD yogurt at home.
Find out why SCD yogurt should be your first go to healing food here.
ADDING SPECIFIC STRAINS OF BACTERIA
Once you are confident making yogurt, you can experiment with adding new strains of bacteria. A few grains of vegetable starter culture or probiotic powder in addition to a yogurt starter culture will produce therapeutic grade yogurt.
Just don’t overdo it; too much bacteria can ruin yogurt. You will know when you have added too much because the texture will be runny or slimy. You needn’t throw it out though. Eating this yogurt will not necessarily harm you. Be guided by your nose. If it smells off or has grown mould, definitely don’t eat it.
BACTERIA ARE HEAT SENSITIVE
Always add your yogurt starter culture to the milk when it is below 108° F (42° C). Temperatures above 43° C will kill bacteria. This step by step recipe will explain further and take the worry out of making yogurt at home.
RECOMMENDED YOGURT STARTER CULTURES
When it comes to probiotics, as with other supplements, there is variation in individual tolerances. At Luvele, we cannot make claims about specific strains or their interaction with your unique body. If your certified GAPS or SCD health practitioner has recommended a particular probiotic brand, we trust their judgment.