SWEET NOTHINGS?
Consumer demand for reduced sugar,
no-added-sugar and sugar free foods and beverages has increased, as
people look to cut back on processed foods with added sugars without
cutting sweet treats out of their lives. Sugar alcohols or polyols are
increasingly replacing them in foods and beverages, often along with
intense sweeteners, as they provide similar bulk and texture to sugars
but fewer kilojoules/calories. We put together the following table to
show you how sugar alcohols compare with added table sugar (sucrose).
A couple of points. While sugar alcohols occur naturally in many
plant foods, they are extracted for the food industry from various
starches and sugars. You may also notice that the GI values differ from
some of the claims you will see on-line and on product packaging. This
is because much of the original GI testing was done before ISO
26642:2010 (Food products -- Determination of the glycaemic index (GI) and recommendation for food classification)
was gazetted in 2010. The ISO sets out how much available carbohydrate
each sugar alcohol (polyol)provides and therefore how much is required
for GI testing. Prof Tom Wolever has adjusted older GI test results
based on the amount of available carbohydrate they contain, and it’s his
result we have included.
As they are generally poorly
absorbed in our intestines (with the notable exception of erythritol),
polyols all provide much less energy than regular sugars. But, with the
exception of xylitol, they are not as sweet as sucrose. Therefore, more
polyols need to be used to attain the same sweetness in a product, or
(more typically), they are blended with an intense sweetener to achieve
the same sweetness as sucrose. A very common example is erythritol,
which is on average only 70% as sweet as sucrose. It is typically
blended with steviol glycosides (“stevia”) to achieve a final product
that has a similar bulk, texture and taste as sucrose, that is also
“natural”.
Most have a lower GI and all have a lower
glycemic load (GL) than sucrose. However, most do provide some available
carbohydrate, so if consumed in large amounts, they will have an effect
on blood glucose levels – though much less than sucrose.
Finding
them in the packaged foods or beverages you buy can be tricky. The good
news is that ingredient lists must include the name of individual sugar
alcohols/polyols if they are used. The bad news is that they are not a
mandatory component of the Nutrition Facts panel in most countries, and
therefore are rarely included. The USA is the notable exception where
they must be included under Total Carbohydrate when a “sugar free”, “no
added sugar” or other sugar claim is made.
Given they
are a kind of carbohydrate and excessive consumption can cause wind,
bloating and diarrhoea, we think this “invisibility” could be a problem
for a significant proportion of the population. It also reminds us that
carbohydrates are generally labelled poorly and that it’s not the sugars
that are hidden. It’s the sugar alcohols/polyols.
We
like the following Nutrition Facts panel for ProYo ice cream and would
like to see this approach or something similar widely adopted so people
can see what’s sweetening the processed food they buy.
Ingredient list: Skim Milk, Whole Milk, Whey Protein
Concentrate, Xylitol (Natural Sweetener), Cane Sugar, Inulin, Natural
Flavors, Ground Vanilla Bean
Read more:
- ISO 26642:2010 (Food products -- Determination of the glycaemic index (GI) and recommendation for food classification).
- Wolever, T. The glycaemic index: a physiological classification of dietary carbohydrate.
- US FDA. A food labelling guide: guidance for industry.
Alan Barclay, PhD is a consultant dietitian and chef (Cert III). He worked for Diabetes Australia (NSW) from 1998–2014 . He is author/co-author of more than 30 scientific publications, and author/co-author of The good Carbs Cookbook (Murdoch Books), Reversing Diabetes (Murdoch Books), The Low GI Diet: Managing Type 2 Diabetes (Hachette Australia) and The Ultimate Guide to Sugars and Sweeteners (The Experiment, New York).
Contact: You can follow him on Twitter or check out his website.
