timpoblete

Made a mac & cheese flavor today, using Ruben's method (magnetic spinning hot plate) and 100g of cheese mix per standard ice cream mix. Turned out like ice cream cheese whiz. Will try it on some Ritz crackers tomorrow.

In terms of homogenization after processing, I usually use a handblender to mix the mixture in a stainless steel bowl in an ice bath. This homogenizes and also speeds up the cooling process. I don't know how long the cooling times are for the plastic bag method, but this takes 10-15mins to get the mix down to <10C.

Ruben, How do you find the current recipe with the powdered milk differs from your standard 60min recipe? Is one better than the other. I've been using the 1 hr method for years now to the delight of everyone that helps me finish off the ice cream and if you're saying we can switch over to 25 mins without negatively effecting the final product then I'm on board. BTW I have a spinning hot plate (per Ruben's post on his blog) and have had great results to date. I do incorporate some gelatin into the mix, per Momofuku Milk Bar (check out their Mind of a Chef episode on Netflix on desserts. Awesome stuff).

Paulraphael, I noticed that in your past posts you've used both gelatin and two yolks in your recipes. How do you incorporate the gelatin into the mix (bloom in liquid or right in and heat for a while, etc)? And does aging in the fridge with the gelatin affect anything?

I think the main concern would be that the liquid is not circulating? Would there be an issue with the liquid at the surfaces solidifying? The reason the stirring magnet is needed is to move the liquid around so that the liquid at the bottom of the bowl doesn't sit there and solidify.

Ruben, does the temperature probe feed temperature information to the machine so that the machine adjusts appropriately or does the machine simply power the probe? Haven't decided if I need one yet.

This is the magnetic stirring hot plate that I'm using. I believe it's an older model of what Ruben is using. I purchase a large triangle shaped stirring rod for this. Also, the pot that I'm using in this picture is not the one that I'm current using (this pic was of my first attempt before purchasing the right size stainless steel mixing bowl from Muji).

I've been using a stirring hot plate for about 2 months now. Works well, keeps hands free, but it takes a little bit of time (about 15 mins to get break 70C) to bring mixes up to temperature. Not a big deal if you're heating the mixture for an hour. I use a stainless steel mixing bowl with a wide surface area at the base, thinner the base the better. Metal should work just a as well as glass since it's just heat transfer

You may also want to check your freezer temperature setting. I recently had issues when someone turned the temperature up on the freezer.

One of the local ice cream shop, Delise Dessert Cafe, uses fruit pectin as the stabilizer in their sorbets.

Bojana - The Jasmine Rhubard combination sounds good! From what I understand from Corvitto's book he claims that it's Lactose in the skimmed milk powder that binds to water. This should mean then that lactose in milk will bind to water. Lactose is a sugar and in readings from icecreamscience it's denatured proteins that bind up water molecules, which is also present in skimmed milk powder (50% lactose, 38% casein protein, which is likely denatured by the evaporation process to turn it into powder), not lactose, which is a sugar (sugars have an anti-feeezing capability which also aid to make the ice cream softer). Someone please correct me if there's a hole in my logic (outside of that massive run on sentence :-)) Back to the ice cream, I ended up substituting the proper amount of whole milk for the skimmed milk powder and water in Corvito's chocolate recipe to maintain the casein/lactose levels, which is achieved after heat treat at 71.4C for 35 mins in a 30cm pan (which is equivalent evaporation time to 60 mins in a 23cm pan). Everything seemed to bind up pretty well and I ended up with a good consistency. The chocolate mix (Mast Brothers chocolate) is aging in the fridge and I'll throw it into the machine later today.

Bojana, or anyone that has read Corvitto and Ruben (icecreamscience) - I'd rather not use skimmed milk powder. Has anyone tried to substitute whole milk or skimmed milk in Corvitto's recipes and heat-treating the milk according to Ruben's technique? Also, how does the target 6-10% fat end up? I plan on trying one of his chocolate recipes today, which limits the fat to 8%. By the way, after having read Corvitto's work, which seems to be geared towards more industrial machinery in terms of his recipes, I did find that his explanations on the Anti-Freezing Power and balancing this against the Negative Anti-Freezing Power (or Hardening Power) of ingredients was very helpful.

paulraphael - thanks for the info on the drawing temperature. Hadn't seen any measurable guidelines on when to actually stop the machine until now.

Yogurt is milk that has had bacteria added to it. The bacteria processes the lactose in the milk (turns it into glucose and galactose I think?), but I don't believe that it does anything to the proteins or the fats that would make them act differently. Thus, frozen yogurt should be treated primary like milk or cream, using proportions based on the fat content and expected protein content. If your frozen yogurt is coming out rock solid, then I would assume it's because the fat content isn't high enough and other factors discussed in this thread regarding ice crystallization and making soft ice cream. On a side note, I've started experimenting with adding yogurt bacteria to ice cream after the heating process (per Ruben's procedure). - The ice cream mix is brought down to 110F-120F and a small scoop of yogurt (on the order of tablespoons) is added and whisked in. - The mixture is maintained at no more than 120F for several hours, just like you would make yogurt at home. - Then the mixture is then chilled. Out of the fridge it's very thick. - The mix is thrown into the machine and outcomes basically frozen ice yogurt/cream. The sweetness is dramatically reduced (due to the bacteria eating up the sugars) and the texture was pretty smooth (didn't have much time in freezer after). It was also tangy, much like yogurt. Only made a very small batch so I've still got some more experimenting to do. The reason to add bacteria to the mixture is if you want probiotics in there to aid with digestion. I'm still figuring out if the bacteria does anything to the texture, but the next several batches will determine if there's anything down this road other than probiotics.

Exactly. And there is no "extra fructose." Invert sugar has the same amount of fructose as the table sugar it's made from. I have never seen real evidence even hinting at health (or other) reasons to avoid it. Beware the pseudoscience of the blogosphere. If you were ever to find a real reason to reduce fructose, you'd want to avoid fruit. After some quick googling, it seems that table sugar (sucrose) is fructose and glucose combined into one molecule that is larger than fructose and glucose individually. Invert sugar has the same ratio of fructose:glucose as sucrose, but the fructose and glucose are separated. Because they are separated (and are smaller molecules) they tend to retain moisture and are less prone to crystallisation than sucrose. I think I'll give Invert Sugar a try. As for the evidence against fructose, it was the article in the NYTimes (http://www.nytimes.com/2011/04/17/magazine/mag-17Sugar-t.html?pagewanted=all&_r=0) and the lecture by UCSF Professor Robert Lustig (posted on YouTube ) that initially motivated me to reduce my fructose intake several years ago. All this ice cream making certainly doesn't help, but I compensate in other ways. Don't need to go into the details and if anyone's interested they can go into the links posted. Fruit does contain Fructose (it's the sweet component of fruit), but all of the other ingredients in fruit, such as the fiber, help to reduce the body's absorption of Fructose and the positive elements of fruit help outweigh the negatives from the Fructose.