Jose Andres (of minibar, America Eats, Jaleo, Zaytinya, and Oyamel) came to Harvard again this semester to talk to us about “Gelation.” He is still a very awesome guest lecturer. Different from last year? Rather than talk and watch video demos, Jose and his team demonstrated the behavior of water with each of the different gelation methods: gelatin (made from animal collagen), pectin (from fruit), agar agar (seaweed derived), kappa (seaweed derived), iota (seaweed derived), gellan (bacteria derived), and methil/methyl cellulose (plant derived).
Well, ok, he didn’t do much with the pectin. He just showed us the inside of a tomato.
Anyway, he showed us the different textures of water when mixed with 1 sheet, 2 sheets, and 3 sheets of gelatin. With just 1 sheet, the water is thick but still fluid. It’s very sauce like. Once you get to 3 sheets though, you definitely have a type of solid. If you wanted to, you could make a sauce from 1 sheet of gelatin and carrot juice and then make gelatin carrot from 3-4 sheets of gelatin and carrot juice.
With 2 cups of water, some gelatin, and a cream whipper with N2O cartridges, you can make 6 cups of mousse. The water can easily replaced with strawberry juice to make a strawberry mousse. On the same idea, you can take a stand mixer, water, and 4 sheets of gelatin and let it mix for 10 minutes to create a dense cloud of foam. It will have a texture not unlike a meringue. You can mix gelatin, sucrose, and water using an immersion blender to make an airy foam like sea foam. Jose’s favorite use of this is to make a salty foam to serve with margaritas instead of the traditional glass with a salted rim.
Gelatin, however, cannot be served warm/hot. It will melt. Agar agar can be heated and keep it’s shape to 80C. You can make “noodles” out of a liquid and agar agar by letting the mixture spread out thinly on a rimmed baking sheet. When it has set, cut the gel into strips not unlike making tagliatelle or pappardelle. Since agar agar will not melt so easily, the noodles can be served with a heated sauce. (My friend Seth, who came out to see what all the lecture hullabaloo was about, was quick to suggest that kimchi pasta be made with agar agar. I can imagine that – if you use the kimchi sauce – but I don’t know what would make a good sauce for it right now.)
Moving onto carrageenan seaweeds, kappa and iota were demonstrated. Kappa makes a hard and breakable product. On the other hand, iota is soft and elastic. The team made in front of the audience jelly droplets made from iota. Another interesting detail of iota is that if you break up your iota structures and then put it back into a mold, the gelation will re-form. (When Dave Arnold was here, he showed us that agar agar will not reform when broken into pieces. This is not necessarily a bad thing if you use this as a process for clarifying a liquid.)
For gellan, our bacteria derived product and the most recent out of all the gelation products, a gellan disk was zested on a Microplane to make a quick and easy replacement for shark fin (as in shark fin soup).
Like last year, for methyl cellulose (in which gelation happens upon addition of heat), Jose demonstrated a baby corn made from baby corn kernels glued to a tube of agar agar by methyl cellulose. (The agar agar tube would ideally be corn water.) It looks similar to the real thing but Jose promises that it tastes much better.
To finish, Jose and his team demonstrated spherification using 1) a calcium chloride bath to make spheres of alginate+liquid and 2) an alginate bath to make spheres of yogurt (which has calcium already in it. The interaction of alginate and calcium will create a thin membrane while letting the inside stay in liquid form. (However, if you let it sit for too long, the center will eventually turn into a solid as well.)
The subject matter wasn’t different from last year but the delivery was. Regardless, it is hard to dislike Jose Andres. He’s funny, passionate and engaging. Both my sister and my friend Seth who sat in the audience with me thoroughly enjoyed themselves. I am almost tempted to say that if you could only attend one Science and Cooking lecture ever, make sure that it’s with Jose Andres. (Almost… I’m really looking forward to David Chang’s lecture in November, and I hope Dave Arnold comes back next year.)