Monday, February 24, 2014

Comparison Of Two Kickstarter-funded Sous Vide Devices

Sous Vide

Sous vide cooking requires heating a tub of water to a precise temperature and holding it there over a long period of time (often several hours), putting food in plastic bags, evacuating the air from the bags (typically), and dropping the bags in the water for the desired period of time. Often this is followed by removing the food from the bags and normal-cooking it for a brief period (for example, to add a nice charred/seared finish).

There are two basic approaches for keeping temperature constant:
  1. A water bath with heating elements underneath (and sometimes also on the sides) that relies on convection to produce an even temperature throughout. One vendor of these calls them "water ovens".
  2. An immersion circulator that provides heat, plus actively circulates the water to ensure even temperature.
Both approaches use accurate thermometers and control devices (typically PIDs) to avoid thermal undershoot and overshoot. Both approaches have safety features such as low-level sensors, etc.

Advocates for immersion circulators have demonstrated unwanted temperature gradients in water ovens, by dropping a lot of frozen food in the water at once. Water-oven advocates claim this was an unfair test, at least for home use, because the quantity of frozen food was unrealistic. They may or may not have a point.

The one undeniable drawback to the water-oven approach is the size of the machine. In a restaurant, this is perhaps not a concern, but in a house it actually matters. The leading model of water ovens is as big as a bread maker, and for casual home use could be a boat anchor if it's not used all the time (which is true come to think of it of bread makers too). In contrast, an immersion circulator can be clipped into any large pot the home cook already owns, and can be stored in a small volume when not in use.

So, we wanted to buy an immersion circulator instead of a water oven.

Early sous vide experimenters repurposed expensive lab equipment, and at least one lab-equipment vendor (PolyScience) was smart enough to realize they had a new sales channel, and start making purpose-built immersion circulators.

But they were still expensive.

Note: PolyScience sells lower-priced immersion circulators: https://www.cuisinetechnology.com/sousvide-professional-comparison.php. But we didn't know about them at the time, or perhaps they were recently introduced. We only knew about immersion circulators costing $700 or more.

Kickstarters

While we were looking for an affordable model, Nomiku did a Kickstarter for a lower-cost (but still high-quality) immersion circulator: https://www.kickstarter.com/projects/nomiku/nomiku-bring-sous-vide-into-your-kitchen.

We invested in one.

Then Sansaire did a Kickstarter for another immersion circulator: https://www.kickstarter.com/projects/seattlefoodgeek/sansaire-sous-vide-circulator-for-199.

We invested in one of those as well, in case the Nomiku failed to deliver, or wasn't any good.

(Note that both projects were funded quickly and greatly exceeded their funding goals. There was obviously pent-up demand for such a product.)

Comparisons

Having now received both units and tried them out, here is our evaluation:

Nomiku
  • Smaller (width and height)
  • Quieter
  • More expensive
  • Cover is recommended to keep heat in, and pre-notched cover is not available from vendor
  • Slower to reach desired temperature
  • Smaller range of water levels
  • Harder to clean inside
Sansaire
  • Bigger (width and height)
  • Louder (but still not very loud)
  • Less expensive
  • No cover needed
  • Reaches desired temperature quickly
  • Larger range of water levels
  • Easier to clean inside
  • Some burrs on mounting clip (they're working on improving this)
Both
  • Well-designed
  • Well-manufactured
  • Well-documented
  • Well-packaged
  • Excellent customer support
  • Prompt shipping
  • Hold constant temperature correctly with little or no variance once equilibrium is reached
We haven't used either unit long enough to comment on long-term reliability. At some point I'll post an update.

Recommendations

If space is at a premium and/or if you plan to only cook small amounts, get the Nomiku. Otherwise, get the Sansaire.

Misc

Despite showing metal pots on their websites, both vendors recommend using Cambro polycarbonate tubs (12 quart for Nomiku: http://www.amazon.com/gp/product/B0001MRUKA/, 4.75 gallon for Sansaire: http://www.amazon.com/gp/product/B00ADPF9V2/). The tub recommended for the Sansaire has ridges on the underside that provide some insulation from cold countertops.

Although not required for the Sansaire, a cover will reduce evaporation, and holds in heat (which reduces energy cost, but does not affect the ability of the Sansaire to keep constant temperature). No pre-notched cover is available for the Sansaire (same as for the Nomiku), and cutting one would be problematic for a Sansaire because the hole would need to be some distance from the edge, producing a long void that would leak heat. If you want a cover with the Sansaire, you can use floating plastic balls, which are available from usplastics.com (case of 1000, 20mm, polypropylene floating spheres: http://www.usplastic.com/catalog/item.aspx?itemid=62936&catid=641). These are also sold by PolyScience, in smaller quantity, for a lot more money.

(PolyScience sells tubs and pre-cut covers, in various sizes, for their immersion circulators. It would be helpful if Nomiku did the same.)

Photos

Side-by-side comparison of Sansaire and Nomiku, in recommended tubs:


Nomiku cover, courtesy of my brother. Hole was cut with 2+1/4" hole saw in a drill. Notch connecting edge to hole was cut with fine-toothed hacksaw. Edges were lightly sanded, but googling around for advice on how to cut polycarbonate, some posts recommend lightly running a butane torch flame over the cuts, which will (they claim) melt them gently into a smooth finish.

If you screw up, you can get another top from Amazon for about $9.




Similar review on another site: http://mobile.seriouseats.com/2013/12/sous-vide-circulator-review-sansaire-nomiku-anova.html.

3 comments:

  1. The one undeniable drawback to the water-oven approach is the size of the machine. In a restaurant, this is perhaps not a concern, but in a house it actually matters.

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