Read this if your homemade yogurt is too sour, lumpy or watery. By Estelle Low
Troubleshoot yogurt-making. Photo: Derennes/photocuisine/Corbis
What’s the best milk to make yogurt with?
Gene: Generally, milk that contains lactose and protein are suitable. I prefer to use full-cream milk for a creamy consistency, though low-fat or skimmed milk works as well. Avoid using milk that contains milk powder, as that might affect the consistency. Personally, I like using Greenfields milk as it has a neutral taste, which makes a good base for toppings like berries, granola, almonds etc. That yogurt is also great for baking, as the neutral taste won’t overpower the main flavour. Taste is subjective, so feel free to experiment with different brands of milk until you find one that suits your taste.
Why do I have to add yogurt to one part of the milk first, instead of the whole milk mixture?
Gene: In short, for smoother consistency. Adding the yogurt to a small part of the milk (as opposed to the entire volume of milk) makes it easier for the yogurt to be well incorporated. Then when you combine the yogurt-milk mixture with the remaining milk, you can be sure of a more even consistency.
Why does my yogurt turn out lumpy?
Gene: Here are some common reasons.
- Not letting the mixture set for long enough. A minimum of four hours is required to let the yogurt-milk mixture form a firm consistency.
- Stirring or moving the mixture while it sets. Doing so breaks the bonds that are required for the yogurt-milk mixture to gel.
- Using flavoured milk instead of plain milk. The flavouring used may be reactive to heat treatment or even acid released by the yogurt’s bacteria, resulting in an inconsistent texture. With this in mind, it’s advisable to flavour the yogurt after fermentation.
- Having an inconsistent temperature during the setting process. 43 to 49 deg C is the optimal temperature range to keep the bacteria in the yogurt alive and active. A higher temperature (above 49 deg C) would kill the bacteria; a lower temperature (below 43 deg C) would mean that the bacteria would not multiply as quickly.
Why does my yogurt turn out watery?
Gene: Certain types of milk have a higher water content, which slows down the gelling process of the yogurt-milk mixture. Typically, full-cream milk gives the creamiest consistency. If you’re using the same milk again, heat it for a longer time to evaporate more water for a thicker texture.
What happens if I left my yogurt out for more than the recommended four to eight hours?
Gene: If you’ve left your yogurt to set for more than eight hours, it is very likely that the holding temperature (43 to 49 deg C) has dropped significantly, which means that there’s a chance that other bacteria has become active. I wouldn’t advise someone to eat it for safety reasons. However, if the temperature was maintained throughout, it’s possible to consume the yogurt — just that it’d be firmer and tarter than what you’d expect.
How long can I keep homemade yogurt for?
Gene: Preferably no more than a week, since there are no preservatives added and there might be other types of bacteria multiplying in the yogurt. Taste wise, the yogurt will become tarter and firmer as it will continue to ferment even in the fridge. To play it safe, make just enough for three to five days.