Chlorogenic acid (CQA), the ester of caffeic acid with quinic acid, has been one of the most studied polyphenols due to its potential biological activity and usefulness in pharmaceutical treatment. We found that in an aqueous solution of each chlorogenic acid isomer, 3-, 4- and 5-CQA, its two complexes with water are formed. In the RP chromatographic system, these CQA-water derivatives differ in retention data from that of their precursors and do not decompose, which indicates their considerable stability. The formation of CQA-water complexes has not been reported yet. Comprehensive NMR research of CQA-water derivatives complexes shows that their significant stability results from the formation of hydrogen bonds between water and CQA isomer – e.g., between water and OH3, OH4 and ester groups of CQA molecule in the case of 5-CQA-water derivative. The existence of CQA-water derivatives in CQA containing food products was in the paper shown. It should be noted that the stable CQA-water complexes may exhibit a different biological activity than CQA. This issue requires separate biomedical research.

In this study, Sea Water Bread (SWB), made with food grade sea water was compared with control bread made with Tap Water (TWB). Sea water’s influence on chemical-nutritional properties of bread was investigated. Contents of salt, macro/micro-elements, basic nutrients, polyphenols, antioxidant activity, olfactory characteristics, and volatile components were analyzed. Chlorides’ analysis showed SWB had a lower salt content than TWB and it was confirmed by ICP-OES investigation. An electronic nose confirmed differences between the groups of aromatic molecules of the bread typologies, as well as the profiles of the volatile molecules by GC-MS.

The valorisation and management of agri‐food waste are currently hot investigation topics which probe the recovery of valuable compounds, such as polyphenols. In this study, high‐pressure/high‐temperature extraction (HPTE) and ultrasound‐assisted extraction (UAE) have been used to study the recovery of phenolic compounds from grape marc and olive pomace in hydroalcoholic solutions. The main phenolic compounds in both extracts were identified by HPLC‐DAD. Besides extraction yield (total polyphenol and flavonoid content) and the antiradical power, polyphenol degradation under HPTE and UAE has also been studied. HPTE with ethanol 75% gave higher phenolic extraction yields: 73.8 ± 1.4 mg of gallic acid equivalents per gram of dried matter and 60.0 mg of caffeic acid equivalents per gram of dried matter for grape marc and olive pomace, respectively. In this study, the efficient combination of ethanol/water mixture with HPTE or UAE has been used to enhance the recovery of phenolic compounds from grape marc and olive pomace. HPLC‐DAD showed that UAE prevents phenolic species degradation damage because of its milder operative conditions.

Concerns regarding sustainability have prompted the search of value in the by-products of food manufacturing. Such is the case of the cooking water (CW) of chickpeas, which has shown its potential as a vegan egg white replacement. This study aimed to characterize and compare the CW from three novel legumes (black soybeans, BSB; yellow soybeans, YSB; and small black beans, SBB) obtained from the processing of Korean soybean foods, and the widely used CW from chickpeas (CH), with regard to total polyphenol, total carbohydrate, and protein contents, and further compare their foaming and emulsifying abilities and stabilities. Compositional analysis revealed that all the studied legumes possessed higher values than CH for all parameters. Furthermore, the CW from these legumes exhibited enhanced functional properties, particularly foaming capacity and stability. Taken together, our results suggest that the CW from BSB, YSB, and SBB, sourced from the manufacturing of legume food products, has the potential of being revalorized as a plant-based functional ingredient for vegan product development.

Food colorants are an important class of food additives that give the first impression to consumers about the quality of food. Ce(IV)-reducing antioxidant capacity assay originally developed in our laboratories was adapted to the determination of synthetic food colorants for the first time. This method allowing for total antioxidant capacity assay of dietary polyphenols, flavonoids, and ascorbic acid in plant extracts is based on the room temperature oxidation of antioxidant compounds with Ce(IV) sulfate in dilute H2SO4 solution and measurement of the absorbance of unreacted Ce(IV) at 320 nm. The results of the proposed method were correlated with high-performance liquid chromatography (HPLC) findings. Individual standard solutions, synthetic mixtures of synthetic colorants, and colorant extracts were identified and quantified with HPLC on a C18 column equipped with a diode array detector, and slight modifications on the existing HPLC method were made to analyze synthetic colorant mixtures. This work proposes Ce(IV)-oxidative spectrophotometry as a complementary technique to HPLC in the analysis of food colorants.