The Effect of Yellow Tea Leaves Camellia sinensis on the Quality of Stored Chocolate Confectionery

Research on Application of Japanese Quince (Chaenomeles L.) and Pork Collagen in Dark Chocolate-Benefits in Prevention of Inflammation In Vitro Model

In the present study, the effect of the addition of quince and collagen type I and III to dessert chocolate on its functional properties was determined. The study evaluated the antioxidant potential of the tested formulations using the FRAP method and the linoleic acid oxidation test and beta-carotene bleaching test. The tested samples were also evaluated for inhibitory activity against enzymes important in preventive health (inflammation and neurodegenerative disorders) namely: AChE, BChE, GR, GPx, COX, and SOD. The addition of quince and collagen to the chocolate samples resulted in higher activity compared to the control sample, as indicated by the FRAP test. The experiment highlighted the impact of including quince fruit on the antioxidant activity of the chocolate samples. Interestingly, merely increasing the quince fruit amount did not consistently enhance antioxidant potential. Specifically, chocolate samples with a lower proportion of quince fruit (2 g/100 g) exhibited greater antioxidant activity when supplemented with collagen I. Conversely, in samples with higher quince percentages (3 g and 4 g), those enriched with collagen III showed higher antioxidant activity. Similar correlations were observed in the linoleic acid oxidation test. Notably, samples containing 3 g and 4 g of quince and type III collagen demonstrated statistically similar highest antioxidant properties. Regardless of the collagen type used, there was no observed increase in activity towards the tested enzymes for samples with the lowest percentage of quince fruit. Both collagen types exhibited the highest activity in the inhibition assay against acetylcholinesterase and butyrylcholinesterase when combined with 3 g and 4 g of quince. Overall, the experimental incorporation of both fruit and collagen enhanced the chocolates' activity. Similarly to the antioxidant activity findings, chocolates with lower quince fruit quantities showed increased activity when supplemented with collagen III, while those with higher quince content (3 g and 4 g) displayed higher activity with collagen I. Bitter chocolate by itself is an attractive food product, rich in many bioactive compounds. However, enriching it with other attractive raw materials can make its properties and taste even more attractive.

Yellow tea: more than turning green leaves to yellow

Yellow tea (YT), a slightly-fermented tea originated from Ming Dynasty with distinctive "Three yellows," mild-sweet smell, and mellow taste attributed to the unique yellowing process. Based on current literature and our previous work, we aim to comprehensively illustrate the key processing procedures, characteristic chemical compounds, health benefits and applications, as well as the interlocking relationships among them. Yellowing is the most vital procedure anchored on the organoleptic quality, characteristic chemical components, and bioactivities of YT, which is influenced by temperature, moisture content, duration, and ventilation conditions. Pheophorbides, carotenoids, thearubigins and theabrownins are the major pigments contributing to the "three yellows" appearance. Alcohols, such as terpinol and nerol, are attributed to the refreshing and sweet aroma of bud and small-leaf YT, while heterocyclics and aromatics forming during roasting result in the crispy rice-like large-leaf YT. Hygrothermal effects and enzymatic reactions during yellowing result in the decline of astringent substances. Meanwhile, multiple bioactive compounds such as catechins, ellagitannins, and vitexin, endow YT with antioxidant, anti-metabolic syndrome, anti-cancer, gut microbiota regulation, and organ injury protection effects. Future studies focusing on the standard yellowing process technology, quality evaluation system, and functional factors and mechanisms, possible orientations, and perspectives are guaranteed.

Impact of Bioactive Compounds of Plant Leaf Powders in White Chocolate Production: Changes in Antioxidant Properties during the Technological Processes

Bioactive compounds present in the powdered leaves of matcha green tea (Camellia sinensis L.) (MGTP) and moringa (Moringa oleifera) (MOLP) seem to be related to health benefits due to their antioxidant properties. The growing accessibility of these powders has led to their being more widely used in food production. The aim of this study was to evaluate the total phenolic content (TPC) and antioxidant capacity (AC) of white chocolate (WCh) supplemented with MGTP and MOLP. AC was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric ion-reducing antioxidant capacity (CUPRAC), and ferric-reducing antioxidant power (FRAP) assays, whereas TPC was determined by the Folin–Ciocalteu (FC) method. Both additives were incorporated at four levels (1, 2, 3 and 4%) in two chocolate processing steps (conching and tempering). Additionally, the amounts of phenolic acids, tocopherols, and carotenoids in WCh samples enriched by MGTP and MOLP were determined to explain their influence on AC. The results showed that the chocolates supplemented with MGTP were characterized by higher antioxidant properties than those with MOLP. In turn, MOLP significantly increased the content of lipophilic antioxidants in chocolates, tocopherols and carotenoids, which also exhibit pro-health effects. Furthermore, the incorporation of these additives during the tempering process was more relevant to the improvement of the antioxidant properties of WCh.

Processing, chemical signature and food industry applications of Camellia sinensis teas: An overview

The plant Camellia sinensis is the source of different teas (white, green, yellow, oolong, black, and pu-ehr) consumed worldwide, which are classified by the oxidation degree of their bioactive compounds. The sensory (taste, aroma, and body of the drink) and functional properties of teas are affected by the amount of methylxanthines (caffeine and theobromine), amino acids (l-theanine) and reducing sugars in their composition. Additionally, flavan-3-ols, mainly characterized by epicatechins, catechins, and their derivatives, represent on average, 60% of the bioactive compounds in teas. These secondary metabolites from teas are widely recognized for their antioxidant, anti-cancer, and anti-inflammatory properties. Thus, Camellia sinensis extracts and their isolated compounds have been increasingly used by the food industry. However, bioactive compounds are very susceptible to the oxidation caused by processing and degradation under physiological conditions of gastrointestinal digestion. In this context, new approaches/technologies have been developed for the preservation of these compounds. This review presents the main stages involved in production of Camellia sinensis teas following a description of their main bioactive compounds, biological properties, stability and bioaccessibility. Besides, and updated view of Camellia sinensis teas in the field of food science and technology was provided by focusing on novel findings and innovations published in scientific literature over the last five years.

Physicochemical, Antioxidant, Microstructural Properties and Bioaccessibility of Dark Chocolate with Plant Extracts

In this study, dark chocolates (DCh) containing zinc lactate (ZnL) were enriched with extracts from elderberries (EFrE), elderflowers (EFlE), and chokeberries (ChFrE) to improve their functional properties. Both dried plant extracts and chocolates were analyzed for antioxidant capacity (AC) using four different analytical methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric ion-reducing antioxidant capacity (CUPRAC), and ferric-reducing antioxidant power (FRAP), while total phenolic content (TPC) was determined by Folin-Ciocalteu (F-C) assay. An increase in antioxidant properties of fortified chocolates was found, and the bioaccessibility of their antioxidants was evaluated. The highest AC and TPC were found in ChFrE and chocolate with chokeberries (DCh + ChFrE) before and after simulated in vitro digestion. Bioaccessibility studies indicated that during the simulated digestion the AC of all chocolates reduced significantly, whereas insignificant differences in TPC results were observed between chemical and physiological extracts. Moreover, the influence of plant extracts on physicochemical parameters such as moisture content (MC), fat content (FC), and viscosity of chocolates was estimated. Furthermore, scanning electron microscopy with dispersive energy spectroscopy (SEM-EDS) was used to analyze surface properties and differences in the chemical composition of chocolates without and with additives.