The crew of the Jupiter 2 go on short rations two or three times during their adventures in Lost in Space and have to rely on protein pills to maintain themselves, but on the whole they seem to enjoy a balanced diet with a lot of variety in it. This in itself raises questions insofar as while the source of fresh vegetables (the hydroponic garden) can justify some of the variety, the simple question of storage space seems to preclude the abundance of tinned food, flour, sugar, coffee, and meat (chicken and meatloaf are specifically mentioned or seen in different episodes) that appear regularly. And then there is also the question of eggs…
In “There Were Giants in the Earth” Judy is planting crops in the newly erected hydroponic garden. When questioned by Dr. Smith, we learn that the Robinsons will supplement their stored food with asparagus, corn, potatoes and peas. One has to assume that hydroponics has advanced a great deal by 1997 to allow vegetables like these to be grown in any significant quantity in about three square metres of bedding, but there you have it. Other plants that appear in the hydroponic garden are celery, carrots, and cabbage.
In “Attack of the Monster Plants” Dr. Smith’s campsite has a number of tinned provisions (notably pork and beans) stored off to the side against a rock. Even granting that some of them are reproductions thanks to the plants he encounters, and even assuming that he only received his share of stores from the Jupiter 2, one is forced to believe that the Jupiter 2 has vast amounts of preserved food on board. Storage space was indeed seen on occasion, but still, the amount they used versus the amount they could have been carrying in storage just don't jibe.
Maureen suggests using the last of the flour to make celebratory biscuits on one occasion, although sandwiches figure in later episodes. Perhaps the corn crop came in and they were able to use corn meal instead (although the sandwiches look like kaiser rolls, not corn bread). Despite the apparent lack of eggs on Priplanus (and one can safely assume in the stores of the Jupiter 2), Penny does find an egg in the wild (“Return from Outer Space”). Despite this, breakfast scenes often seem to show lashings of scrambled eggs on the table. Coffee and the ingredients for cakes never seem to be in short supply either.
In true die-hard want-it-to-be-true fan fashion, I do think there is an answer, and it is not too far-fetched. In the galley one wall was covered with a number of transparent plastic bubbles which held different coloured contents. Given their location in the galley (and Maureen being a biophysicist) one might assume that these items were the chemical building blocks the advanced galley uses to create food for the Robinsons (pace what the Alpha Control Reference Manual says). It is conceivable that storing such elements would pose less of a problem than tinned food, sides of beef, and sacks of sugar, flour, and coffee. There are one or two occasions when Maureen says she wonders what has been prepared for them to eat, then presses a button and their meal emerges down the conveyor belt in the middle of the table; this does seem to imply that the food is being “built” from available resources, especially since the results are occasionally less than appetising.