So, after a lot of searching after what are the recommended daily intake in terms of nutrient requirements and other stuff, I used a couple of sources to make an average of what is actually needed, and starting from this extrapolated a need.
Here are my basis per day, for the average astronaut (average between male and female need) with a moderate physical activity:
- Proteins: 50 grams
- Fat: 65 grams
- Carbohydrates: 320 grams
- Sugars: 60 grams
- Sodium: 1.5 grams
- Fiber: 25 grams
- Mixed vitamins: 1 gram (wild shot here based on what is needed and could not be provided by the rest of the ingested food)
The sources for these were from an average of several documents, mainly this document from the European Food Safety Authority, this document from WHO and this document from UK FDF. The amounts where chosen with respect for the upper limits proposed by those authorities.
Overall physical activity in space is usually lower than on Earth, since there are no gravity, but there are some forced physical activity to maintain the state of bones and muscles, so I tended to a moderate physical activity.
This should amount to about 10000 kJ per day (using the 9.4kcal/g for fat, 4.7kcal/g for protein, 3.9kcal/g for carbohydrates and sugar and 2.5kcal/g for fiber). Source for these value are this document.
The bulk of this food amount to a total of 522.5 grams per day, per astronaut.
Please note this is dry food only.
This NASA Document (from the previous answer) gives the information of 120 grams for packaging for the meals.
The same document also gives a reference value of 710 grams of food. However, this amount does seem to include some water since most of the food on the ISS is not dried food.
So per year, this gives about 191kg worth of food and 44kg worth of packaging (or 235kg overall).
Your ballpark was not that far off, and in the right range. The NASA Document for the ISS gives a bit more (260kg of food per year), but this probably includes wet food.
This estimate could probably be reduced by better controlling the activity of the astronauts and a better control of the environment (a bit hotter than needed to reduce the thermogenesis of the body for example).
Small edit to add a bit more information. I fell into the powder food trap and spent the last few days looking for more information.
Some companies are creating their own mix of powdered food, where you just need to add water. If we don't take into account the impact of food quality on astronauts morale, this could be a viable solution to reduce the weight, since they manage to achieve about 150gr of dry powder per meal. This would take the food weight down to 164kg. Also, this kind of powdered food is usually packaged in pouches, so this could significantly lighten the load too if we have a 50gr pouch for each day, that would be a total of 18kg of packaging and a total weight of 182kg.