Highlights

Abstract

Keywords

List of abbreviations

۱٫ Introduction

۲٫ Food digestion

۳٫ Absorption of nanoparticles

۴٫ Intracellular fate of endocytosed particulates

۵٫ Absorption of food colloids

۶٫ In-vivo transportation and biodistribution

۷٫ Dynamic formation and disassembly process of food colloids

۸٫ Safety issue

۹٫ Conclusions and future trends

Funding

Declaration of competing interest

References

Background: Food can be considered as a natural pool of biopolymer-based colloidal particles diverse in size, morphology, and functionalities. There remains considerable controversy on whether these particles can be absorbed from the intestinal lumen in their intact form even though numerous studies have confirmed the possibility of the absorption of intact nanoparticles across the intestinal wall. Scope and approach: In this review, we comprehensively summarize the absorption process of nanoparticles, including mucus-penetrating, cellular uptake, and intracellular transportation. We then perform a detailed study on the absorption of food colloidal particles composed of protein, lipid and carbohydrate. The in-vivo transportation and biodistribution of nanoparticles is then summarized. We also specially discuss the dynamic colloidal aspects of food components which is of great importance to the food digestion and absorption. Finally, we analyze the safety issue of food nanoparticles since an increasing concern on this arises in the past decades. Key findings and conclusions: External nanoparticles can be absorbed into cells through endocytosis, which can occur via different mechanisms. Like various fabricated nanoparticles, food colloidal particles potentially can also be absorbed in their intact form. However, previous studies rarely touch upon the absorption, biological fate, potential health effects, and safety of these colloidal particles. Their dynamic formation and disassembly process is also ignored. All these issues are of great importance to the food digestion and absorption mechanism and worth to be thoroughly studied. We attempt to coin all these relevant studies as “Colloidal Nutrition Science”, which aim to understand the food-body interaction from colloidal aspects.

۱٫ Introduction

Many chemicals naturally found in food matrix are present in a colloidal state such as globulins a few nanometers in diameter, starch granules (~100 nm), or fatty acids several nanometers in length. Traditional processing (e.g., emulsification, heating, or cooling) can generate a variety of multiscale colloidal structures such as micelles, emulsions, foams, gels, or dispersions (Bellmann et al., 2015). There are also endogenous colloidal nanoparticles physiologically produced from ions in the mammalian gastrointestinal tract (GIT) (Powell, Faria, Thomas-McKay, & Pele, 2010). All these colloidal structures generally act as the skeleton in foods. They not only maintain the stability, processing and texture characteristics of foods before consumption but also carry the sensory, digestion, and absorption attributes of foods after ingestion (Lu, Nishinari, Matsukawa, & Fang, 2020). Hence, to understand the interaction of food with the body from a perspective of food colloids is a key to completely uncover food digestion and absorption mechanisms, and thus provide essential basis for the development of functional food products that are applicable to common and/or specific populations (Dickinson, 2015).