Hi Stefanie, it does sound like that might be mold on the sides of the jar, but I don't think your starter is completely hopeless. However, I do think you'll need to change your feeding routine to provide more regular nourishment for your starter when it's stored at room temperature. If your home is warm this time of year, this may be making it more difficult to keep up with your starter's needs, and you might also want to consider storing it in the refrigerator some of the time. Our typical feeding routine consists of twice a day feedings that look like this: 1/2 cup (113g) starter + 1/2 cup (113g) water + 1 scant cup (113g) Unbleached All-Purpose flour. Feeding only once a day and discarding half is leading to starter that is generally sluggish and vulnerable to mold. Ideally, you want to feed your starter when it is ripe (at its highest point of rising, or just beginning to fall) rather than when it has fallen completely. This helps keep yeast activity vigorous and will keep your starter healthy and well-nourished. Adding another feeding per day and discarding all but 1/2 cup (113g) starter will help with this, but if you still find it difficult to line up your twice a day feedings closer to the peak rise, then you also have the option to reduce the percentage of starter, relative to the water/flour you're feeding it. Feeding your starter a larger meal in this way is not harmful and can be a good strategy, particularly during the warmer months when fermentation happens more rapidly. Instead of feeding the usual 1:1:1 (starter:water:flour, by weight), you might want to try something more like 1:4:4, or even 1:5:5. This is obviously easier to accomplish if you have a scale, but in a pinch you could do it by volume. For example, a 1:4:4 feeding would look like this: 1/8 cup (28g) starter + 1/2 cup (113g) water + 1 scant cup (113g) Unbleached All-Purpose flour. 

I would recommend switching to a clean jar (or cleaning your jar thoroughly with very hot water and then air drying it), and then trying 2-3 days of twice a day feedings according to the 1:4:4 feeding routine. Once your starter is rising well and has an improved aroma, then you're back in business! At that point, you also have the option to start refrigerating your starter when you're not planning to bake. Simply give your starter another feeding, let it sit out for 2-4 hours (or until it starts bubbling), and then refrigerate it for up to a week. When you're ready to start baking again, you may find a day or two of twice a day feedings at room temperature will be helpful to improve the activity level of your starter after refrigeration and before baking. Look for your starter to double in size about 6-8 hours after a feeding as a good sign that it is ready to leaven your bread. 

• Reply