Question

Does high methoxyl or low methoxyl pectin require more dehydrating solute(sucrose)? Explain

Answer 1

Pectin is a naturally-occurring polysacharride found in many plants. It has long been the mechanism by which jams and jellies are thickened. High-methoxyl pectin requires a significant amount of sugar to gel properly, but low-methoxyl pectin requires less, which is why low-methoxyl pectin has become popular for pastries and molecular recipes designed not to be as sweet. Low-methoxyl pectin can be used as a gelling agent, thickening agent and stabilizer. Low-methoxyl pectin can be used as a fat substitute in baked goods and to stabilize acidic protein drinks such as drinking yogurt.

Pectin Function

There are two basic types of pectin, though there are many subtypes of pectin within the two basic types. High-methoxyl pectin is the form of pectin traditionally used for canning applications. It requires high amounts of sugar to gel and is very sensitive to acidity. Low-methoxyl pectin has been used in the food industry to create low-sugar jams because it does not require high sugar levels to gel. It is also less sensitive to acidity and requires calcium to gel. Most molecular recipes call for low-methoxyl pectin.

Pectin Applications

Pectin can be used in molecular gastronomy to make a wide variety of dishes. Pectin can be added to sweets and confections to give them texture. Since it's sensitive to calcium, it can be used for spherification. Pectin can be combined with flavoring ingredients and dehydrated to create thin, transparent sheets or edible films.

To create a brittle opaque film, use 15% glucose powder, 1.5% LM pectin and 0.6% agar with 100% of the desired liquid. Cast mixture into a thin film over silicone mat and dehydrate.

Using the gelling properties of LM Pectin you can make a savory pate de fruit with firm and elastic texture using 2% of LM Pectin and 1% of Calcium Lactate Gluconate.

In smaller amounts, pectin thickens liquids much like the gelatin in a rich stock. At higher concentrations, pectin forms an increasingly stronger gel.

Of note, LM Pectin will form a thermoirreversible gel, which means that it will stay gelled even when heated to temperatures that would normally melt it. This is due to the presence of calcium ions.

Hydration: Will only hydrate in the presence of calcium. Ideally, you should add the LM Pectin to a liquid with known low levels of calcium. Then, once the pectin is dispersed, add the calcium source to induce hydration and gelling. A calcium sequestrant may also be used to reduce calcium levels enough that the pectin can disperse.