Emulsionanti e Idrocolloidi

Premessa

Gli idrocolloidi e gli emulsionanti sono entrambi additivi alimentari, ma hanno funzioni diverse. Gli idrocolloidi sono sostanze che addensano, gelificano o stabilizzano alimenti, mentre gli emulsionanti aiutano a miscelare sostanze immiscibili come olio e acqua.

Idrocolloidi
Sono sostanze che, in soluzione acquosa, formano un sistema colloidale, aumentando la viscosità o formando gel.
La loro funzione principale è quella di modificare la consistenza degli alimenti, rendendoli più densi, cremosi o gelatinosi.
Possono anche stabilizzare le emulsioni o le sospensioni, impedendo la separazione delle fasi.
Alcuni esempi di idrocolloidi: agar-agar, amidi modificati, beta-glucani, carragenine, pectina, semi di carruba, fibre di bambù, fibre di patata, fibre di pisello, gelatine, gomma arabica, gomma xantana, guar, inulina. In quali prodotti è più facile trovarli: prodotti da forno e da pasticceria, biscotti, gelati, yogurt, bevande sportive (in particolare maltodestrine).

Emulsionanti:
Sono molecole che hanno una parte idrofoba (amante del grasso) e una parte idrofila (amante dell’acqua).
Questa struttura permette loro di stabilizzare le emulsioni, ovvero miscele di liquidi immiscibili come olio e acqua.
Gli emulsionanti si dispongono tra le due fasi, riducendo la tensione superficiale e prevenendo la separazione.
Esempi comuni includono lecitina, mono e digliceridi degli acidi grassi e polisorbatati.
In sintesi, mentre gli idrocolloidi modificano la consistenza generale di un alimento, gli emulsionanti lavorano specificamente per mantenere stabili le emulsioni, evitando la separazione di olio e acqua. Alcuni idrocolloidi, come la lecitina, possono anche avere proprietà emulsionanti.

Emulsionanti

In evidenza 
Un recente studio, pubblicato su The Lancet Diabetes & Endocrinology ha valutato per la prima volta l’associazione tra emulsionanti e rischio di sviluppare diabete di tipo 2

I – Emulsionanti e rischio diabete: lo studio di Lancet
Dopo essere stati accusati di contribuire al rischio di obesità, cancro e malattie cardiovascolari, un’analisi recente condotta sullo studio prospettico di coorte NutriNet Santé li identifica come fattori che aumentano il rischio di diabete di tipo 2.
Sebbene le Autorità Sanitarie considerino sicuro il loro uso in quantità definite, basandosi su criteri di citotossicità e genotossicità, di recente stanno emergendo prove dei loro effetti negativi sul microbiota intestinale, che a sua volta innescano infiammazione e alterazioni metaboliche.
Un recente studio, pubblicato su The Lancet Diabetes & Endocrinology ha valutato per la prima volta l’associazione tra emulsionanti e rischio di sviluppare diabete di tipo 2. Gli Autori hanno analizzato i dati di oltre 104 mila adulti arruolati dal 2009 al 2023 a cui è stato chiesto di compilare registri dietetici di 24 ore ogni 6 mesi. L’obiettivo era valutare l’esposizione agli emulsionanti.
L’1% del campione, ha sviluppato diabete di tipo 2 durante il follow up di 6-8 anni.
Dei 61 additivi identificati, sono sette gli emulsionanti ‘attenzionati’ associati a un potenziale aumento del rischio di diabete (occhi, quindi, alle etichette!):
E407 (carragenine totali);
E340 (esteri di poliglicerolo);
E472e (esteri di acidi grassi);
E331 (citrato di sodio);
E412 (gomma di guar);
E414 (gomma arabica);
E415 (gomma di xantano);
oltre ad un gruppo chiamato ‘carragenine’.
Gli additivi emulsionanti sono stati assunti nel 5% da frutta e verdure ultra lavorate (come verdure in scatola e frutta sciroppata), nel 14.7% da torte e biscotti, nel 10% da prodotti lattiero-caseari.
Tre conseguenze sottolineate dal prof. Angelo Avogaro, Presidente SID
1. La necessità di contenere il consumo di cibi ultra-processati;
2. l’appello a una maggiore attenzione alle etichette;
3. la necessità di chiedere una regolamentazione più stringente allo scopo di proteggere i consumatori.
“Sebbene siano necessari ulteriori studi a lungo termine, le alterazioni del microbiota intestinale, fanno ritenere che potrebbe essere necessario rivedere gli RDA (Recommended Daily Allowance, livelli giornalieri di assunzione). Precedenti prove che legavano l’assunzione di carragenina all’infiammazione intestinale hanno portato l’JECFA a limitarne l’uso nelle formule e negli alimenti per neonati. Stiamo assistendo a un preoccupante aumento del diabete di tipo 2 anche tra bambini e adolescenti” sottolinea la Prof.ssa Raffaella Buzzetti, Presidente eletto SID.
References
Cosa sono gli emulsionanti e quali sono gli esempi comuni di tali sostanze utilizzate negli alimenti?
Food additive emulsifiers and the risk of type 2 diabetes: analysis of data from the NutriNet-Santé prospective cohort study. The Lancet Diabete and Endocrinology, volume 12, issue 5, p339-349, May 2024.

L – Abstract.
Background: Epidemiologic evidence and animal studies implicate dietary emulsifiers in contributing to the increased prevalence of diseases associated with intestinal inflammation, including inflammatory bowel diseases and metabolic syndrome. Two synthetic emulsifiers in particular, carboxymethylcellulose and polysorbate 80, profoundly impact intestinal microbiota in a manner that promotes gut inflammation and associated disease states. In contrast, the extent to which other food additives with emulsifying properties might impact intestinal microbiota composition and function is not yet known.
….omissis. Conclusions: These results indicate that numerous, but not all, commonly used emulsifiers can directly alter gut microbiota in a manner expected to promote intestinal inflammation. Moreover, these data suggest that clinical trials are needed to reduce the usage of the most detrimental compounds in favor of the use of emulsifying agents with no or low impact on the microbiota. Direct impact of commonly used dietary emulsifiers on human gut microbiota. Sabrine Naimi. https://doi.org/10.1186/s40168-020-00996-6.

M- …………omissis. We found dietary emulsifiers to significantly alter human gut microbiota toward a composition and functionality with potentially higher pro-inflammatory properties. While donor-dependent differences in microbiota response were observed, our in vitro experimental setup showed these effects to be primarily emulsifierdependent. Rhamnolipids and sophorolipids had the strongest impact with a sharp decrease in intact cell counts, an increased abundance in potentially pathogenic genera-like Escherichia/Shigella and Fusobacterium, a decreased abundance of beneficial Bacteroidetes and Barnesiella, and a predicted increase in flagellar assembly and general motility. The latter was not substantiated through direct measurements, though. The effects were less pronounced for soy lecithin, while chemical emulsifiers P80 and CMC showed the smallest effects. Short chain fatty acid production, with butyrate production, in particular, was also affected by the respective emulsifiers, again in an emulsifier‐ and donordependent manner.

….omissis. One of the most profound impacts of emulsifier treatment toward gut microbiota was the decline in intact microbial cell counts. The degree of microbiome elimination in this study seems comparable to what has been observed for antibiotic treatments (Francino, 2016; Guirro et al., 2019). Since antibiotics are considered detrimental for gut ecology, this may serve as a warning sign with respect to emulsifier usage. Emulsifiers also act as surfactants, which are known for their membrane solubilizing properties (Jones, 1999). The fact that the observed decline in microbial viability was dependent on emulsifier dose and on the emulsifying potential of the supplemented compound, as measured by the aqueous surface tension reduction (Table 1), leads us to conclude that the dietary emulsifiers attack the bacterial cells principally at the level of the cell membrane.

………….omissis. A last important element in the putative health impact from dietary emulsifiers concern’s interindividual variability. An individual’s unique microbiota and metabolism are important determinants of the potential health effects dietary emulsifiers could cause. While the overall effects from the different emulsifiers toward microbiota composition and functionality were quite consistent in our study, important interindividual differences in susceptibility of the microbiota were noted. Understanding what underlying factors and determinants drive this interindividual variability will be crucial to future health risk assessment of novel and existing dietary emulsifiers.

N – Common dietary emulsifiers promote metabolic disorders and intestinal microbiota dysbiosis in mice. Suraphan Panyod et al. 2024 https://doi.org/10.1038/s42003-024-06224-3.

Dietary emulsifiers are linked to various diseases. The recent discovery of the role of gut microbiota–host interactions on health and disease warrants the safety reassessment of dietary emulsifiers through the lens of gut microbiota. Lecithin, sucrose fatty acid esters, carboxymethylcellulose (CMC), and mono- and diglycerides (MDG) emulsifiers are common dietary emulsifiers with high exposure levelsin the population. This study demonstrates that sucrose fatty acid esters and carboxymethylcellulose induce hyperglycemia and hyperinsulinemia in a mouse model. Lecithin, sucrose fatty acid esters, and CMC disrupt glucose homeostasis in the in vitro insulinresistance model. MDG impairs circulating lipid and glucose metabolism. All emulsifiers change the intestinal microbiota diversity and induce gut microbiota dysbiosis. Lecithin, sucrose fatty acid esters, and CMC do not impact mucus–bacterial interactions, whereas MDG tends to cause bacterial encroachment into the inner mucus layer and enhance inflammation potential by raising circulating lipopolysaccharide. Our findings demonstrate the safety concerns associated with using dietary emulsifiers, suggesting that they could lead to metabolic syndromes.

M – Abstract Objective Carboxymethylcellulose (CMC), one of the most common emulsifiers used in the food industry, has been reported to promote chronic inflammatory diseases, but its impact on acute inflammatory diseases, e.g., acute pancreatitis (AP), remains unclear. This study investigates the detrimental effects of CMC on AP and the potential for mitigation through Akkermansia muciniphila or butyrate supplementation.

Design C57BL/6 mice were given pure water or CMC solution (1%) for 4 weeks and then subjected to caeruleininduced AP. The pancreas, colon, and blood were sampled for molecular and immune parameters associated with AP severity. Gut microbiota composition was assessed using 16S rRNA gene amplicon sequencing. Fecal microbiota transplantation (FMT) was used to illustrate gut microbiota’s role in mediating the effects of CMC on host mice. Additional investigations included single-cell RNA sequencing, monocytes-specific C/EBPδ knockdown, LPS blocking, fecal short-chain fatty acids (SCFAs) quantification, and Akkermansia muciniphila or butyrate supplementation. Finally, the gut microbiota of AP patients with different severity was analyzed.
Results CMC exacerbated AP with gut dysbiosis. FMT from CMC-fed mice transferred such adverse effects to recipient mice, while single-cell analysis showed an increase in classical monocytes in blood. LPS-stimulated C/EBPδ, caused by an impaired gut barrier, drives monocytes towards classical phenotype. LPS antagonist (eritoran), Akkermansia muciniphila or butyrate supplementation ameliorates CMC-induced AP exacerbation. Fecal Akkermansia muciniphila abundance was negatively correlated with AP severity in patients.
Dietary emulsifier carboxymethylcellulose-induced gut dysbiosis and SCFA reduction aggravate acute pancreatitis through classical monocyte activation. Feng et al. Microbiome (2025) 13:83 https://doi.org/10.1186/s40168-025-02074-1

NOTA

L’Efsa (l’Autorità europea per la sicurezza alimentare) ha stabilito che i prodotti che riportano i claim sui benefici dell’idrossipropilmetilcellulosa devono riportare anche l’avvertimento della possibilità di soffocamento in caso di difficoltà di deglutizione o se ingeriti con una quantità di fluidi insufficienti. Per questi motivi è importante assumere l’idrossipropilmetilcellulosa insieme ad acqua abbondante, in modo da assicurarsi che raggiunga lo stomaco. L’idrossipropilmetilcellulosa E464 svolge diversi compiti, principalmente è usato come agente addensante, fibra alimentare, agente anti-aggregante e filmogeno. È simile alla cellulosa, ma presenta una migliore solubilità in acqua. Trova impiego nelle farine e nei prodotti gluten-free dove viene impiegata per migliorare le caratteristiche reologiche degli impasti e quelle organolettiche dei prodotti per celiaci.

In sintesi
Emulsifiers and microbiome
some studies suggest that certain emulsifiers can promote gut dysbiosis, an imbalance in the gut microbiome. This can lead to inflammation and potentially contribute to metabolic disorders and other health issues.
Here’s a more detailed explanation:
Emulsifiers and Gut Microbiota:
Emulsifiers are substances that help mix liquids that don’t normally combine, like oil and water. They are commonly found in processed foods. Research indicates that some emulsifiers can alter the composition and function of gut bacteria.
How Emulsifiers Might Cause Dysbiosis:
Increased Permeability: Emulsifiers may increase the permeability of the intestinal barrier, allowing bacteria and their byproducts to leak into the bloodstream.
Changes in Bacterial Populations: Some emulsifiers have been shown to decrease the diversity of gut bacteria and increase the abundance of certain bacteria linked to inflammation.
Metabolic Impacts: These changes in the gut microbiome can contribute to metabolic disorders like obesity, insulin resistance, and inflammation.
Examples of Emulsifiers:
Studies have focused on emulsifiers like polysorbate 80 (P80) and carboxymethylcellulose (CMC), finding that they can disrupt the gut barrier and promote inflammation.
Implications for Health:
Gut dysbiosis, particularly when influenced by emulsifiers, has been linked to conditions like metabolic syndrome, inflammatory bowel disease, and other chronic inflammatory diseases.
It’s important to note:
The effects of emulsifiers on the gut microbiome can vary depending on the specific emulsifier, the individual’s microbiome, and other dietary factors.
More research is needed to fully understand the long-term effects of emulsifier consumption on human health.
Some emulsifiers, like mono- and diglycerides, have been associated with negative health outcomes, while others, like inulin, may help to restore a healthy gut microbiome.