Novel encapsulation approaches for phytosterols and their importance in food products: A review

Abstract

Phytosterols are naturally occurring plant cell membranes, which have received greater attention in food industries due to their potential health benefits especially lowering low‐density lipoprotein (LDL) cholesterol levels within the human body. However, the application of phytosterols in various foods (aqueous‐based) is challenging due to their low water solubility and poor stability resulting in poor bioavailability/bioaccessibility. The encapsulation technique is considered as an alternative approach to protect phytosterols from various factors, thus improving their bioavailability and stability. This review aims in presenting a detailed study on techniques and technologies currently employed to encapsulate phytosterols. Based on recent studies, mostly used techniques are spray drying, freeze drying, spray chilling, emulsification, liposome entrapment, extrusion, electro‐spinning, and electro‐spraying. Various processing factors affecting phytosterol stability in fortified food have been outlined as well. Practical Applications Phytosterols are plant‐based bioactive compounds that have been commonly linked to having anti‐diabetic, anti‐inflammatory properties and cholesterol‐lowering effects. Consumption of processed and ready‐to‐eat foods lowers the intake of plant sterols in the human diet. Additionally, their availability in plant‐based foods is also limited. Phytosterol fortified foods are now available to fulfill the phytosterol requirement in our diet. The consumption of phytosterol enriched foods or supplements can be an alternative option to lower cholesterol levels in the human body. However, phytosterols are insoluble in water which results in poor bioavailability and stability. Furthermore, the incorporation of phytosterols in food products is difficult due to the probability of oxidation at higher processing temperatures and storage. Hence, encapsulation is an alternative approach to enhance phytosterols' stability and bioavailability.

Effects of food formulation on bioavailability of phytosterols: phytosterol structures, delivery carriers, and food matrices

“…3) have been designed to defend PSs from a variety of environmental factors and mechanical forces, minimize their crystallization during processing and storage, regulate the release of PSs in the GIT, and increase their absorption in the GIT. 5,22,38 The usage of delivery carriers in food has expanded the scope of PS applications in food and significantly improved their bioavailability.…”

“…Nanoemulsions are emulsions with a droplet size of 100–500 nm, usually prepared by treatment of high-pressure homogenizers, microfluidizers, sonicators, etc . 5 PSs in the nanoemulsion also show better stabilities and lower crystallizations due to their smaller drop sizes. 40 The reduction of the droplet size can also promote the hydrolysis of fat and the release of PSs for increasing the contact area between fat and digestive enzymes.…”

“…regulate the release of PSs in the GIT, and increase their absorption in the GIT. 5,22,38 The usage of delivery carriers in food has expanded the scope of PS applications in food and significantly improved their bioavailability.…”

“…4 The European Food Safety Authority (EFSA) and the Food and Drug Administration (FDA) recommend a daily intake of about 2-3 g of PSs to reduce cholesterol levels by 10%. 5 A previous study showed that the cholesterol-lowering activity of PSs can be achieved by precipitating cholesterol or competing with cholesterol to incorporate mixed micelles. 6 In subsequent studies, it was found that PSs can also inhibit the synthesis and transport of cholesterol by influencing the formation of certain related enzymes and carrier proteins.…”

Effect of pH and biopolymer ratio on phase behavior, rheology, and structural characteristics of pea protein isolate‐locust bean gum coacervates

“…3 Proteins, lipids, and carbohydrates plays a significant role in holding the structure-property relationships. [4][5][6][7] Previously, animal-based protein and polysaccharide sources like whey, casein, gelatin, and chitosan had been used as shell/wall materials due to their better technofunctional properties. 8,9 However, utilization of these sources shows a downward trend due to dietary restrictions, allergic nature, and sustainability issues.…”