All in a Day's Work

Just thought I'd walk you through some of the moments we've had at SAFI while we've been attempting to do research over here.

In case you're wondering where we are, we've refunctioned one of the empty classrooms at SAFI into our research lab. Hence the equations on the chalk board. This room also happens to be where we work out to Jillian Michaels and Rodney Yee after dinner.

The solar dryer needed a bit of fixing up when we arrived, so we had Adam take a look and buy supplies for us (he's quite the handyman). We had to caulk up all the cracks, but we didn't have anything to spread it with. So Whitney and I used our fingers. After a number of other repairs, the solar dryer was good to go!

The hours of research we've put into this project in this conference room are innumerable.

So one of the things we're testing is the effect of osmotically dehydrating the sweet potatoes before we put them into the solar dryer. We do that through using salt and sugar to create brines of various concentrations.
We usually make the brines the night before we start a run. 

Then we peel the sweet potatoes, using the awesome potato peelers that Dr. Lloyd sent to us.
These peelers beat using a pocketknife by a landslide, which is what we had to do the first time around.

After they're peeled, we use the mandoline (that Dr. Lloyd also sent us, what an angel)
to slice the sweet potatoes into even 4 mm slices.

Then we use the scale and a knife to make sure that each 4 mm slice is only 6-8 g each to limit variability in drying times. After all the slices are of the same weight, we dump 1000g worth of slices into each of the four brines we're using where they soak for 120 minutes. 

After the slices are done soaking, we weigh each slice and place them into a prearranged position on either the drying mat or the solar dryer rack. That allows us to take the weight as we take water activity, so we can see how the osmotic dehydration affected moisture loss as opposed to actual water activity. 

After the slices have been weighed and placed onto the solar dryer racks or on the drying mat, we take them outside, and  let the sun do its thing. This is the solar dryer that we're using. 

Three times a day, we take three slices of each pretreatment from both the solar and air-dried samples and take the water activity. Before we can take the water activity though, we have to rerecord its weight to measure water loss. 

The smaller the pieces are, the more accurate the water activity reading will be.
So we chop up all the samples into pretty small pieces. 

Sometimes the electricity goes out, so I take water activity  by flashlight.

If the water activity reading of any one pretreatment is below .8, we record all the weights of the slices of that particular pretreatment and bag them into whirlpak bags. We plan on vacuum-packing them in the future as well.
We're saving them for further sensory and nutritional analysis.

And here's the entire grupo of food science interns. In the back, that's John and Whitney. And then me and Renee in the front. We have a good time, and overall, the research is going well. We just had two successful runs, and are starting our third tomorrow (our first couple runs were busts, although they were certainly learning experiences haha). We usually do water activity right after dinner, which is also when we work out, so hence, why we're all in workout clothes.

Welp, that's what we do when we're not teaching nutrition lessons, interviewing families, taking anthropometric measurements, and traveling around Malawi. Or sitting in our rooms. Or eating. Or just talking. Not everything that we do here is super exciting haha.

We're in a race against time right now, as our calibration liquid for the water activity meter is starting to go bad, and we only have one more tube left. Fingers are crossed. It will be crazy. But afterwards, we'll get to play, more or less. We've got some more projects we've got to finish up, but it won't be nearly as busy.

It's good stuff. It's a good time.