A heat sealing apparatus including a first sealing bar having a first sealing bar contact surface with a first resistance heating element extending along the upper sealing bar contact surface; a second sealing bar having a second sealing bar contact surface; a sealing bar moving mechanism for moving the first sealing bar and the second sealing bar away from and toward each other into compression contact; a power pulsing mechanism including a microprocessor running a computer program for delivering electric power pulses to the first resistance heating element in selected pulse durations separated by at least one selected interval duration and at a frequency between 0.001 and 5000 Hertz; an electric power source and an apparatus circuit including the first resistance heating element and the sealing bar moving mechanism.