Does allulose glycate proteins at a higher rate than even glucose?

#1

D-allulose was found to be more reactive than fructose and glucose in glycation reactions.[15]

Rare sugars are defined as monosaccharides and their derivatives that are rarely observed in nature. Most popular rare sugars are D-allulose, D-tagatose, D-allose, and D-sorbose. D-Allulose (also known as D-psicose) is the C-3 epimer of fructose. It is not commonly found in nature and exists in small amounts in the leaves of Itea plant (Zuina), wheat, and some bacteria (Hossain, Yamaguchi, Matsuo, Tsukamoto, & Toyoda, 2015). Since D-allulose is also a reducing sugar, it undergoes Maillard reaction when heated with proteins and produces enhanced functional properties (Hossain et al., 2015). Glycation of α-lactalbumin with D-allulose, fructose, and glucose was investigated and it was found that Maillard reaction rate, antioxidant activity, and the browning degree was the highest at D-allulose modified proteins (Sun et al., 2006; Sun, Hayakawa, Ogawa, Fukada, & Izumori, 2008).

Microwave heating is an alternative to the conventional glycation process since it provides higher heating rates with shorter times. There are few studies about microwave glycation of proteins in the literature and most of the studies concluded that microwave glycation was an effective way for protein modification (Bi et al., 2015; Guan et al., 2011; Nasrollahzadeh, Varidi, Koocheki, & Hadizadeh, 2017). Soy protein isolate (SPI) glycation with microwave heating by using lactose, maltose, dextran and soluble starch as sugar sources revealed that use of microwaves enhanced the mobility of sugar molecules, therefore, increased the reaction rate (Guan, Qiu, Liu, Hua, & Ma, 2006). Moreover, another study reported that the microwave irradiation could be the reason for the increase of water exposure to hydrophobic core residues of protein and breaking of the disulfide bonds, thus increasing the reaction rate (Guan et al., 2011).

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The addition of d-allulose can make products produce a stronger water holding capacity in foods compared with that of sucrose. Soy gels with added d-allulose have a remarkable impact on digestive behavior, a property that can be used to design low-calorie, satiety enhancing confectionery products [62,63]. Unlike sucrose and sorbitol, heating of myofibrillar protein with d-allulose facilitates the formation of both disulfide and non-disulfide crosslinks, which may be related to the mechanical properties and water holding capacity of d-allulose gels [64]. Functional foods and formulas for special medical purposes that utilize d-allulose in the Maillard reaction with proteins are effective in the prevention of dental caries and related diseases caused by oxidative stress. A recent longitudinal study on d-allulose, in which the lifespan of Caenorhabditis elegans was increased under both monogenic and axenic culture conditions, found increased resistance to oxidative stress by d-allulose through a dietary restriction mechanism [65]. These results suggest that d-allulose is an excellent candidate for dietary restriction mimetics.

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#2

Good to know. When I use allulose, I usually add it directly in powdered form to coffee or cereal, or for instance to fresh strawberries rather than cooking w/it. Would be important to know if it also forms AGEs in vivo when ingested without cooking.

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#3

Allulose will form AGEs in vivo after absorption, and it is most certainly a lot more glycating than glucose. On the other hand, it isn’t completely absorbed. Only a majority of it seems to be absorbed, not all of it. Also it has some other benefits so it’s hard to say whether the increased glycation outweighs the other benefits it may have.

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#4

Personally I would avoid all refined sugars and sweeteners, including stevia. I have personally known people who have had reactions to various “sweetners”, from severe chronic headaches (aspartame) to chronic diarrhea (xylitol, any -tol).
An unanticipated effect occurred when I completely stopped eating anything sweet; sweet things began to taste extremely strong and almost poisonous like an acid. Even apples that have been breed to be very sweet are distasteful.

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#5

Per these studies, the Maillard reaction products of allulose (aka psicose) are actually antioxidants with potential health benefits.

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#6

Interesting topic especially given the recent controversy around erythritol.

Blood and tissue concentrations will be much lower than glucose. Even more so than fructose, which is already a couple orders of magnitude lower (which is why some question whether fructose significantly contributes to AGEs https://www.sciencedirect.com/science/article/pii/S2161831323002223). How much does this matter?

Also, is intracellular metabolism required for significant AGE formation? It is not metabolized.

#7

Intracellular damage is harder to measure and way more important than extracellular damage… It’s very relevant for glucose

#8

It can get into cells in a variety of tissues through GLUT5 but don’t know whether entry is enough or whether metabolism is required for significant AGE formation. I don’t know much about that. Here is the tissue distribution in rodents (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4207542/). At least there’s little brain exposure.