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Fujitsu harvests low-potassium lettuce grown in semiconductor plant

japantimes.co.jp

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Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#31

Post by nkurz »

ChuckMcM wrote: post #24
mikegreen wrote: post #17

Earlier quoted context omitted.

Growing more food per acre in an indoor hydroponic farm is a reality today. The problem is your romaine from that hydro farm down the road is $3.99, and from the traditional farm shipped across the country is $1.99. Lights are a big part of the equation. Most plants need 10+ hours of sunlight a day, so even if you put the plants on a rotisserie you still have to supplement with artificial light ($$$). The amount of w…

Do you have any links/references for a large scale hydroponics operation? This was the last significant piece I read ( http://modernfarmer.com/2013/06/dirt-free-farming-will-hydro... ) which was from last June that talked primarily about the costs. There are externalities that are increasing the cost of 'land' farming, among them water availability, GMO concerns, pest control, and land/labor costs. At some point robo…

These guys are large scale and down your way: http://www.viridisaquaponics.com/

They have 8 acres of greenhouse in Watsonville, and a producing some really impressive quantities of greens: more than 10 times per acre per year over conventional. They are aquaponic, which means they are growing both vegetables and fish (mostly sturgeon in their case). I have a friend with lots of traditional ag experience who visited them recently, and he seemed close to proclaiming they were the path to the future. I'll join you if you wrangle a tour.

Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#32

Post by ars »

chc wrote: post #30
ars wrote: post #23

Earlier quoted context omitted.

> it stays fresh for about two weeks That's hardly special. I've stored lettuce that I bought commercially for 4 weeks and it was fine. So that's 4 weeks plus however long it took to get to me. (I bought too much by mistake.)

Was that at 10°C or higher?

No, it was lower. In a fridge.

Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#33

Post by chc »

ars wrote: post #32
chc wrote: post #30

Earlier quoted context omitted.

Was that at 10°C or higher?

No, it was lower. In a fridge.

Then it sounds like better preservation would be expected. The article says it lasts two weeks at 10°C. I have no idea how exceptional that is as I've never knowingly stored lettuce at 10°C, but it probably doesn't last as long as lettuce as refrigerator temperatures.

Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#34

Post by andor »

ChuckMcM wrote: post #24
mikegreen wrote: post #17

Earlier quoted context omitted.

Growing more food per acre in an indoor hydroponic farm is a reality today. The problem is your romaine from that hydro farm down the road is $3.99, and from the traditional farm shipped across the country is $1.99. Lights are a big part of the equation. Most plants need 10+ hours of sunlight a day, so even if you put the plants on a rotisserie you still have to supplement with artificial light ($$$). The amount of w…

Do you have any links/references for a large scale hydroponics operation? This was the last significant piece I read ( http://modernfarmer.com/2013/06/dirt-free-farming-will-hydro... ) which was from last June that talked primarily about the costs. There are externalities that are increasing the cost of 'land' farming, among them water availability, GMO concerns, pest control, and land/labor costs. At some point robo…

Do you have any links/references for a large scale hydroponics operation?

According to [0] from 2000, about 8% of the greenhouses in Almeria, Spain use hydroponics. [1] from 2010 says it's now 10%. The pictures in [2] show that 10% is still a lot...

[0] http://www.schundler.com/spain.htm

[1] http://books.google.com/books?id=5Ag-wT0rLEMC&pg=PA47&lpg=PA...

[2] http://www.amusingplanet.com/2013/08/the-greenhouses-of-alme...

Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#35

Post by ChuckMcM »

nkurz wrote: post #31
ChuckMcM wrote: post #24

Earlier quoted context omitted.

Do you have any links/references for a large scale hydroponics operation? This was the last significant piece I read ( http://modernfarmer.com/2013/06/dirt-free-farming-will-hydro... ) which was from last June that talked primarily about the costs. There are externalities that are increasing the cost of 'land' farming, among them water availability, GMO concerns, pest control, and land/labor costs. At some point robo…

These guys are large scale and down your way: http://www.viridisaquaponics.com/ They have 8 acres of greenhouse in Watsonville, and a producing some really impressive quantities of greens: more than 10 times per acre per year over conventional. They are aquaponic, which means they are growing both vegetables and fish (mostly sturgeon in their case). I have a friend with lots of traditional ag experience who visited t…

Nice! I've 'reached out' to them, to use the vernacular, to see if they are open to informal tours. I'd love to see the control systems they use in a place like that. And understand where their current challenges are.

Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#36

Post by seandougall »

walshemj wrote: post #15
MrBuddyCasino wrote: post #4

Previously: https://news.ycombinator.com/item?id=7749595 They grow that stuff for people with kidney problems, they have to follow a diet that is low in potassium.

Indeed we do - though my advice from the renal dieticians didn't mention lettuce - will have to ask at my next checkup. Ironically when I aske about the lo-salt versions of things like soy sauce she commented no the crap they put in to replace salt is worse :-)

I've been seeing nephrologists (some of the best in the country) for almost a decade, and none of them has ever been remotely useful in planning out a diet. Neither have the nutritionists they've sent me to. They all know lots about nutrition, but they don't know anything about food. They also get really cagey/evasive when you try to ask for quantifiable guidelines -- like "tell me how many milligrams of potassium to stay under per day".

And don't get me started on hospital food. (Short version: my "renal diet" at Cedars Sinai was just half-portions of the regular diet -- including half a banana, and a 4-oz container of orange juice. No joke.)

Watching serving sizes is the trick, because "suggested" serving sizes are usually totally unrealistic. People will tell you to avoid spinach like the plague because they're used to thinking of it as a crapton of leaves boiled down to a few spoonfuls. But they might make you so paranoid that you avoid a sandwich that has three leaves of fresh spinach on it, despite the fact that there's more potassium in the bread! And conversely, they might not mention potatoes, because the suggested serving size is so small, but you'll get a ton of potassium if you eat a giant plate of french fries (potato skins even more so).

Some things nobody told me:

1) A baked potato has twice as much potassium as a banana.

2) So does an avocado.

3) Some fancy grains, like quinoa, are reasonably high in potassium.

4) Foods claiming to be "a good source of potassium" aren't always the most potassium-rich; that's just marketing, and tells you more about the calories per unit potassium than it does about the potassium per serving.

5) The USDA nutritional database is one of the most useful things our government has ever done: http://ndb.nal.usda.gov/ndb/search/list

Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#37

Post by Someone »

chc wrote: post #33
ars wrote: post #32

Earlier quoted context omitted.

No, it was lower. In a fridge.

Then it sounds like better preservation would be expected. The article says it lasts two weeks at 10°C. I have no idea how exceptional that is as I've never knowingly stored lettuce at 10°C, but it probably doesn't last as long as lettuce as refrigerator temperatures.

Http://cooking.stackexchange.com/questions/33540/does-a-head-of-lettuce-really-need-to-be-refrigerated gives a table showing that leaf lettuce at 10 degrees C evaporates only about 30% faster than leaf lettuce at 5 degrees C. That difference isn't that large.

It also gives head lettuce at best two weeks at five degrees centigrade. So, two weeks at 10 degrees seems a good result.

On the other hand, the article says _about_ two weeks; they might mean 'ten days plus', and 'freshness' may be highly subjective (I bet there is a standard for measuring lettuce freshness)

Re: Fujitsu harvests low-potassium lettuce grown in semiconductor plant

#38

Post by mikegreen »

Someone wrote: post #37
chc wrote: post #33

Earlier quoted context omitted.

Then it sounds like better preservation would be expected. The article says it lasts two weeks at 10°C. I have no idea how exceptional that is as I've never knowingly stored lettuce at 10°C, but it probably doesn't last as long as lettuce as refrigerator temperatures.

Http://cooking.stackexchange.com/questions/33540/does-a-head-of-lettuce-really-need-to-be-refrigerated gives a table showing that leaf lettuce at 10 degrees C evaporates only about 30% faster than leaf lettuce at 5 degrees C. That difference isn't that large. It also gives head lettuce at best two weeks at five degrees centigrade. So, two weeks at 10 degrees seems a good result. On the other hand, the article says _a…

Humidity is a huge component of lettuce lifespan. You can't just plop lettuce into your fridge near 0c as it is quite dry (hence why fridges have crispers that maintain higher humidity for veggies, and are selectable to low humidity for fruits).

Frankly, if you're not using a head of lettuce in 2 weeks something is wrong with your eating and/or buying decision making :-)

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