Simplify the following text for a Grade 7 native English-speaking person.
Original: Prior to Heinz ( and his fellow innovators ) , commercial tomato ketchups of that time were watery and thin , in part due to the use of unripe tomatoes , which were low in pectin .
Simplified: Prior to Heinz ( and his fellow innovators ) , commercial tomato ketchups of that time were watery and thin . This was due to the use of unripe tomatoes .