Fuente: WIPO "meat" Cell lines that can be utilized in fed-batch processes are provided. In preferred embodiments, the cell lines have been modified to reduce or eliminate the production of byproduct(s) that adversely impact cell proliferation and/or viability in fed-batch processes. In some embodiments, the cells are modified by inactivating one or more genes that encode for lactate production. Exemplary genes include lactate dehydrogenase A (LDHA) and pyruvate dehydrogenase kinase 1 (PDK1). Also provided are methods of making and using the cells, for example in food products.