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Phenolic compounds are known to degrade and/or undergo changes during food production and storage. Reaction kinetic modeling is generally used to define kinetic parameters of a food system and predict changes during thermal processing and storage. Data for phenolic acids and flavonoids, such as anthocyanins and flavan-3-ols, have been reviewed in detail, but the flavonoid sub-classes, dihydrochalcones and flavanones, have been mostly neglected. Other neglected phenolic classes are xanthones and benzophenones. The stability of these types of compounds is important as they are present in fruits and exposed to heat when processed into juice and jam. Other sources of the compounds are herbal teas, which are also subjected to thermal processing, either during the primary processing of the plant material, or the production of extracts for use as food ingredients. The theoretical background is given to understand the review of literature on these classes/sub-classes. Results of research on kinetic modeling are discussed in detail, while research on compound stability without the application of reaction kinetic modeling is briefly mentioned to provide context. The studies discussed included those focusing on heating during the processing and storage of model solutions, liquid foods, plant material, dried extracts, and extracts formulated with other food ingredients. [ABSTRACT FROM AUTHOR]

Phytosomes consist of a phytochemical bound to the hydrophilic choline head of a phospholipid. Their use in food products is gaining interest. However, literature on the use of food‐grade solvents, crude plant extracts as opposed to pure compounds, and unrefined phospholipids to prepare phytosomes is limited. Furthermore, studies on compound stability are lacking. This study aimed to develop nano‐phytosome vesicles prepared from inexpensive food‐grade ingredients to improve the stability of polyphenolic compounds. Cyclopia subternata extract (CSE) was selected as a source of phenolic compounds. It contains substantial quantities of C‐glucosyl xanthones, benzophenones, and dihydrochalcones, compounds largely neglected to date. The effect of process conditions on the complexation of CSE polyphenols with minimally refined food‐grade fat‐free soybean lecithin (PC) was studied. The PC:CSE ratio, sonication time, and reaction temperature were varied. This resulted in phytosomes ranging in vesicle size (113.7–312.7 nm), polydispersity index (0.31–0.48), and zeta potential (−55.0 to −38.9 mV). Variation was also observed in the yield (93.5%–96.0%), encapsulation efficiency (3.7%–79.0%), and loading capacity (LC, 1.3%–14.7%). Vesicle size and LC could be tailored by adjusting the sonication time and PC:CSE ratio, respectively. Chemical interaction between the lipid and the phenolic compounds was confirmed with nuclear magnetic resonance. Phytosomal formulation protected the compounds against degradation when freeze‐dried samples were stored at 25 and 40°C for 6 months at low relative humidity. The study provided valuable information on the importance of specific process parameters in producing food‐grade phytosomes with improved phenolic stability. [ABSTRACT FROM AUTHOR]