The vikings are recognised in history as fierce warriors and excellent sailors, but they were also skilled navigators and traders. This led to them discovering many new lands and being the first foreign faces numerous countries had seen in a long time. Their long boats were small in comparison to war ships, but fast and had the advantage of being quite shallow, something that allowed them to get further up rivers than the boats of their rivals.
After it was discovered that a reasonably small vessel could make the voyage to England and back, thousands of ships over the next few hundred years made the voyage to the new lands, to trade goods with some and raid others, but how did they even make it across the ocean when no one else could before?
The distance between Scandinavia and England is about 350 miles at the closest point, a voyage that would take a colonial era ship about 10 days, depending on the wind, so a realistic estimate for a viking longboat would be around 2 weeks. Additional days or weeks could be added depending on where they were going, but generally no more than 2 weeks on open ocean before coast was in sight.
A typical 2 week Viking ships diet per person:
4kg of grain (Oats or Barley, they didn’t have corn and wheat didn’t grow well in the region)
7-10kg vegetables (Only vegetables that could last the voyage were taken, such as turnips, carrots, onions, peas and beans)
1kg sweet food (honey or fruit, normally just apples or pears)
2kg salted meats (salt pork or one of their other readily available meats, or salted/ dried fish)
Meals at sea would have consisted of cereal dishes and stews, made by simply adding all the ingredients at once into some water. Long-ships didn’t have fires built into them, and so all their food would normally have been eaten cold. A load of raw vegetables mashed up in some water doesn’t sound like it would be fun to eat for 2 weeks straight.
This may also seem like a large amount of food for 2 weeks, and these are only estimate as the vikings didn’t tend to write things down, but one thing that’s mentioned about the vikings time and time again in historical documents is that they loved their food. The English describe them as glutenous and talk about how they ate and drank far to much, and this is reflected in their almost over supplying of rations for a reasonably short voyage.
Since Scandinavia is so cold, grain doesn’t grow well there and fruits are very limited, making it harder to stock up on things like hardtack and fruit leather. Fortunately for the vikings the voyage to their newly found lands wasn’t very long in comparison to the 3 month voyage to America people of the 1600’s had to make, and so food wouldn’t be in the form of long lasting preservable goods like pemmican and potted meat.
Voyage food would have consisted of fresh vegetables and salted meats, mostly pork, goat and horse. Cows weren’t largely raised as the land was hilly and cold and wasn’t the best climate for cows or their food, so goat, pig and horse were the main meats.
Dried onions can last for weeks if not months, and carrots can last for a few weeks from the point they are harvested. The little grain they did produce would also be on the ships menu, and salted or dried fish was considered a staple at the time.
Unfortunately the vikings weren’t known for their long term survival foods as they simply didn’t need them. After realising they could reach fresh water and the chance to resupply food after no more than 2 weeks at sea, the vikings didn’t need to invent things to last for long periods of time as so don’t have any historic survival foods attributed to them.
For look at a real struggle at sea and the kind of food you would need to get to America, have a look at How to survive a voyage to America in the 17th century