As a natural flavonoid, neohesperidin is susceptible to the influence of temperature, pH, light, oxygen and other factors during food processing and storage, resulting in the destruction of its structure or the reduction of its activity, thus affecting its function and stability. To improve its stability in food, it is necessary to start from molecular modification, carrier embedding, environmental control and other aspects, the specific strategies are as follows:
1. Molecular structure modification: to enhance its own stability
Modify the structure of neohesperidoside by chemical or biological means, to improve its tolerance to environmental factors:
Esterification modification: the hydroxyl group of neohesperidoside and fatty acids (e.g., stearic acid, palmitic acid) through the esterification reaction combined to form a fat-soluble derivatives. Such derivatives have improved solubility in fat-based foods (e.g., chocolate, baked goods) and increased resistance to heat and oxidation. For example, esterification of the 3-position hydroxyl group of neohesperidin improves the retention rate by more than 30% under high temperature treatment at 121℃.
Glycosylation modification: Glucose, galactose and other monosaccharides are attached to the glycosidic chain of neohesperidin by glycosyltransferase to increase its water solubility and spatial resistance, and to reduce the destruction of glycosidic bond by pH fluctuation (e.g., in acidic beverages). Studies have shown that the degradation rate of glycosylated neohesperidin in beverages stored at pH 3.0-5.0 for 3 months is reduced by about 50%.
Chelation with metal ions: The phenolic hydroxyl group of neohesperidin can form stable chelates with metal ions such as Ca²⁺ and Zn²⁺, which reduces the attack on the phenolic ring by oxygen and free radicals. In dairy products (e.g., yogurt, milk), chelation can be achieved by utilizing naturally occurring calcium ions, while enhancing the synergistic absorption of minerals.
2. Carrier-embedding technology: building a physical protective barrier
The use of microcapsules, nanoparticles and other carriers to encapsulate neohesperidin, isolated from the external environment (eg, light, oxygen, enzymes), while improving its dispersion:
Liposome-embedding: the use of phospholipids as the wall material to form a liposome vesicle, in which the neohesperidin is encapsulated. The bilayer structure of liposomes protects them from damage by acidic conditions (e.g. fruit juices, carbonated drinks) and high temperature sterilization (e.g. pasteurization), and they can be released slowly in the gut. For example, liposome-embedded neohesperidin was retained at 85% in juice after sterilization at 60°C, compared to 42% in the unembedded group.
Polysaccharide/Protein Complex Embedding: Natural polymers such as gum arabic, chitosan, whey proteins, etc. are used to form microcapsules by spray drying or emulsification. The hydrophilicity of polysaccharides enhances the dispersion of neohesperidin in water-based foods (e.g., beverages, jellies), while the thermal stability of proteins enhances its temperature resistance in baked and fried foods. It was shown that the retention of neohesperidin embedded in chitosan-whey protein composite was increased to more than 70% after baking (180 °C, 15 min) in cookies.
Nanofiber embedding: Neohesperidin was embedded in polylactic acid (PLA) or gelatin nanofibers by electrostatic spinning to form a film-like carrier. Such carriers can be used in food packaging film, not only to protect the stability of the new hesperidin, but also in the food storage process of slow release, play the role of antioxidant, freshness.
3. The environmental control of food system: optimize the application conditions
According to the physicochemical properties of neohesperidin, adjust the formulation of food and processing parameters to reduce the impact of unfavorable factors:
Control of pH range: neohesperidin is more stable under neutral to weakly alkaline conditions (pH 6.0-8.0), while glycosidic hydrolysis is likely to occur in a strongly acidic (pH < 3.0) or strongly alkaline (pH> 9.0) environment. Therefore, in acidic foods (e.g. fruit juices, vinegar drinks), pH can be adjusted to 4.0-5.0 by adding buffering agents (e.g. sodium citrate), and antacids (e.g. dipotassium phosphate) can be used to minimize degradation.
Avoid high temperature and long time processing: New hesperidin is susceptible to thermal degradation under high temperature above 100℃, especially under aerobic conditions. Low-temperature sterilization techniques (e.g. ultra-high pressure sterilization, pulsed electric field sterilization) can be used to replace traditional high-temperature sterilization, or shorten the time of high-temperature treatment (e.g. frying foods at 160℃ or less, duration < 5 minutes).
Synergistic protection with antioxidants: Compound neohesperidin with antioxidants such as vitamin C, tea polyphenols, rosemary extract, etc., and utilize their synergistic effect to scavenge free radicals in the system and reduce oxidative degradation.
Avoid light and oxygen storage: Hesperidin is sensitive to ultraviolet rays and prone to photo-oxidation. Food packaging can be used brown glass bottles, aluminum foil composite film and other light-avoiding materials, while filling the package with nitrogen (such as bottled beverages) isolation.