Effect of sucrose on the anthocyanin and antioxidant capacity of mulberry extract during high temperature heating

Unveiling the multifaceted world of anthocyanins: Biosynthesis pathway, natural sources, extraction methods, copigmentation, encapsulation techniques, and future food applications

Numerous datasets regarding anthocyanins have been noted elsewhere. These previous studies emphasized that all processes must be carried out meticulously from the source used to obtain anthocyanins to their inclusion in relevant applications. However, today, full standardization has not yet been achieved for these processes. For this, presenting the latest developments regarding anthocyanins under one roof would be a useful approach to guide the scientific literature. The current review was designed to serve the stated points. In this context, their biosynthesis pathway was elaborated. Superior potential of fruits and certain by-products in obtaining anthocyanins was revealed compared to their other counterparts. Health-promoting benefits of anthocyanins were detailed. Also, the situation of innovative techniques (ultrasound-assisted extraction, subcritical water extraction, pulse electrical field extraction, and so on) in the anthocyanin extraction was explained. The stability issues, which is one of the most important problems limiting the use of anthocyanins in applications were discussed. The role of copigmentation and various encapsulation techniques in solving these stability problems was summarized. This critical review is a map that provides detailed information about the processes from obtaining anthocyanins, which stand out with their functional properties, to their incorporation into various systems.

Bioavailability of Anthocyanins: Whole Foods versus Extracts

Anthocyanins have gained significant popularity in recent years for their diverse health benefits, yet their limited bioavailability poses a challenge. To address this concern, technologies have emerged to enhance anthocyanin concentration, often isolating these compounds from other food constituents. However, the extent to which isolated anthocyanins confer health benefits compared to their whole-food counterparts remains unclear. This review explores the current literature on anthocyanin bioavailability and metabolism in the body, with a focus on comparing bioavailability when consumed as extracts versus whole foods rich in anthocyanins, drawing from in vitro, in vivo, and human clinical studies. While direct comparisons between anthocyanin bioavailability in whole foods versus isolates are scarce, prevailing evidence favours whole-food consumption over anthocyanin extracts. Further clinical investigations, preferably with direct comparisons, are needed to validate these findings and elucidate the nuanced interplay between anthocyanins and food matrices, informing future research directions and practical recommendations.

Dye stability of black cherry plum anthocyanins in the interaction with co-pigments and sucrose sweetener

In this research, the co-pigmentation reactions between black cherry plum (Prunus cerasifera Ehrh. cv. Pissardii Nigra) anthocyanins and caffeic, gallic, 4-hydroxybenzoic, malic, and tannic acids with different concentrations (0, 120, 240, 480, and 960 mg L-1) at various temperatures (20, 40, 60, 80, and 100°C) were investigated at pH 3.5. The strongest immediate co-pigmentations resulted at 960 mg L-1, being significantly highest using tannic acid at all temperatures. In addition, the anthocyanin stability and the brown polymeric color formation were investigated in the presence of different concentrations of sucrose sweetener (0, 30, and 60%) and different pHs (2 and 3) in the range of 0-60 h. Also, the amount of furfural was measured in the presence of 0% and 30% sucrose concentrations at pH 2 after 20 h at 90°C by HPLC (high-performance liquid chromatography), and the most polymeric color formation was observed in the concentration of 60% sucrose at pH 2 after 60 h.

Effects of sucrose and copigment sources on the major anthocyanins isolated from sour cherries

Cyanidin-3-O-glucosylrutinoside and cyanidin-3-O-rutinoside were isolated from sour cherry juice concentrate (SCJC). Sucrose and copigments [gallic acid (GA), cherry stem extract (CSE) and pomegranate rind extract (PRE)] were added to these anthocyanins. Effects of sucrose and copigments on the isolated anthocyanins were studied during storage at 20 °C for 140 days. All copigment sources provided protection against degradation effect of sucrose on the isolated anthocyanins before storage. Although GA increased the stabilities of both isolated anthocyanins, only CSE had copigmentation effect on both isolated anthocyanins. Copigmentation effect on cyanidin-3-O-glucosylrutinoside continued throughout storage. However, this effect on cyanidin-3-O-rutinoside continued for only 56 days of storage. Cyanidin-3-O-glucosylrutinoside containing three sugar moieties was more prone to copigmentation than cyanidine-3-rutinoside containing two sugar moieties. Results showed that the presence of more than one anthocyanin in a media changed stability of copigmentation. We recommend CSE for enhancement in colour density, but GA for enhancement in anthocyanin stability.

Antioxidant activities of fresh grape juices prepared using various household processing methods

The purpose of this study was to evaluate and compare the antioxidant activities, and their contents, in grape juices prepared by various household juicers, and grape flesh (GF). The grape juices were prepared using a low-speed masticating (LSM) juicer, a high-speed centrifugal (HSC) juicer, and a blender (BLD). The total polyphenol, total flavonoid, total monomeric anthocyanin, and vitamin C contents were highest in the LSM grape juice, and decreased in the order: LSM > BLD > HSC > GF. The antioxidant activities such as DPPH radical scavenging activity, and SOD-like activity were significantly higher in the LSM juice than in other juices and grape flesh. The antioxidant activities and the quality of grape juices were significantly affected by the household juicing method used, and an LSM juicer is strongly recommended for making healthy grape juice, rich in antioxidants.

MdSnRK1.1 interacts with MdJAZ18 to regulate sucrose-induced anthocyanin and proanthocyanidin accumulation in apple

Sugars induce anthocyanin biosynthesis in plants. As a conserved energy sensor, SnRK1 (SNF1-related kinase 1) is involved in sucrose-induced anthocyanin accumulation. However, the exact molecular mechanism by which SnRK1 regulates the biosynthesis of anthocyanins and proanthocyanidins (PAs) in response to sucrose in plants is not clear. In this study, it was found that MdSnRK1.1 interacted with MdJAZ18 protein which acts as a repressor in the jasmonate (JA) signaling pathway. MdSnRK1.1 then phosphorylated MdJAZ18 to facilitate its 26S proteasome-mediated degradation, which released MdbHLH3 thereby activating the expression of the regulatory and structural genes, thus finally promoting the biosynthesis of anthocyanins and PAs. Taken together, these results demonstrate the involvement of MdSnRK1.1 in sucrose-induced accumulation of anthocyanins and PAs. For the first time, our findings shed light on the molecular mechanism by which the crosstalk of sucrose and JA signaling regulates flavonoid biosynthesis.

Sonodegradation of cyanidin-3-glucosylrutinoside: degradation kinetic analysis and its impact on antioxidant capacity in vitro

BACKGROUND

As an alternative preservation method for thermal treatment, ultrasound comprises a novel non-thermal processing technology that can significantly avoid undesirable nutritional changes. However, the recent literature indicates that anthocyanin degradation occurs when ultrasound is applied in juice at high amplitude parameters. Such work has mainly focussed on the effect of ultrasound on stability, the antioxidant capacity of cyanidin-3-glucosylrutinoside (Cy-3-glc-rut) and the correlation between anthocyanin degradation and ·OH generation in a simulated system.

RESULTS

The spectral intensities of Cy-3-glc-rut at 518 and 282 nm decreased with increasing ultrasound power and treatment time. The degradation of Cy-3-glc-rut was consistent with first-order reaction kinetics (r²  > 0.9000) and there was a good linear correlation between anthocyanin degradation and hydroxyl radical formation induced by ultrasound (r²  = 0.9258). Moreover, a decrease in the antioxidant activity of Cy-3-glc-rut after ultrasound evaluated by the 1,1-diphenyl-2-picrylhydrazyl and ferric reducing antioxidant power methods was observed.

CONCLUSION

Overall, the results of the present study show that ultrasound will accelerate the degradation of Cy-3-glc-rut with the growth of power over time. © 2016 Society of Chemical Industry.

Fortification of dark chocolate with spray dried black mulberry (Morus nigra) waste extract encapsulated in chitosan-coated liposomes and bioaccessability studies

Fine-disperse anionic liposomes containing black mulberry (Morus nigra) extract (BME) were prepared by high pressure homogenization at 25,000 psi. Primary liposomes were coated with cationic chitosan (0.4, w/v%) using the layer-by-layer depositing method and mixed with maltodextrin (MD) (20, w/v%) prior to spray drying. After that, spray dried liposomal powders containing BME were added to chocolates with alkalization degrees (pH 4.5, 6, 7.5) at conching temperatures of 40 °C, 60 °C, and 80 °C. The results showed that, compared to spray dried extract, chitosan coated liposomal powders provided better protection of anthocyanin content in both increased temperature and pH. In addition, encapsulation in liposomes enhanced in vitro bioaccessability of anthocyanins. Chocolate was fortified with encapsulated anthocyanins maximum 76.8% depending on conching temperature and pH.

The application of response surface methodology in studying the effect of heat and high hydrostatic pressure on anthocyanins, polyphenol oxidase, and peroxidase of mulberry (Morus nigra) juice

BACKGROUND

Mulberry juice is an excellent source of phytochemicals with medicinal properties. The effects of four independent variables (temperature, heating time, pressure, and pressurising time) on three response variables [% anthocyanin retained, and % residual activities of the enzymes polyphenol oxidase (PPO), and peroxidase (POD)] of mulberry juice were studied using response surface methodology. Mathematical models and optimum levels of the response variables were generated.

RESULTS

Temperature had the greatest effect on all the response variables. The synergistic effect of temperature and pressure had significant effect (P < 0.05) on anthocyanin retained and residual PPO activity. The prediction of the desirability model, based on 95% confidence in the range of the independent variables, gave optimal treatment conditions of 83.39°C, 2.38 min, 480.00 MPa, and 21.67 min, respectively for temperature, heating time, pressure, and pressurising time. At these levels, the corresponding response variables were 91.68%, 44.69% and 20.17% for the amounts of anthocyanin retained, and residual activities of PPO and POD, respectively. The desirability index obtained was 0.741.

CONCLUSION

The results were desirable and the mathematical models developed could be used to predict the outcome of the response variables to a high degree of accuracy.

Composition and antioxidant activity of red fruit liqueurs

Fruits traditionally used for liqueurs are a good source of phenolic compounds endowed with antioxidant activity. The aim of this study was to compare the content of phenolic compounds and anthocyanins and the antioxidant capacity of liqueurs made from red fruits. The liqueurs were made from fruits of 10 species: chokeberry, cornelian cherry, black rose, blackcurrant, blackberry, raspberry, mahonia, sloe, strawberry, and sour cherry. The liqueurs from black rose, chokeberry, sloe and mahonia fruits contained the most of substances which react with the Folin-Ciocalteu reagent (671, 329, 271 and 218 mg GAE/100 mL, respectively) and had the highest antioxidant activity. The samples stored at a temperature of 30 °C had antioxidant activity from 3% to 11% lower than the fresh samples. After 6 months, anthocyanins degraded almost completely in the samples stored at 30 °C and at 15 °C there was from 0% (blackcurrant liqueurs) to 47% (sloe liqueurs) of their initial content and slightly more in sweet liqueurs.

Assessing the effects of different pectins addition on color quality and antioxidant properties of blackberry jam

Background

In the last years pectin and other hydrocolloids were tested for improving the color stability and the retention of bioactive compounds in gelled fruit-based products. In line with these concerns, our study has been directed to quantify the changes in antioxidant status and color indices of blackberry jam obtained with different types of pectin (degree of esterification: DE, degree of amidation: DA) and doses in response to processing and storage for 1, 3 and 6 months at 20°C.

Results

Blackberry jam was obtained by a traditional procedure used in households or small-scale systems with different commercial pectins (HMP: high-methoxyl pectin, LMP: low-methoxyl pectin and LMAP: low-methoxyl amidated pectin) added to three concentrations (0.3, 0.7 and 1.0%) and investigated in terms of total monomeric anthocyanins (TMA), antioxidant capacity expressed as ferric reducing antioxidant power (FRAP), total phenolics (TP), color density (CD) and percent of polymeric color, PC (%). Thermal processing resulted in significant depreciation of analyzed parameters reported to the corresponding values of fresh fruit as follows: TMA (69-82%), TP (33-55%) and FRAP (18-52%). Biologically active compounds and color were best retained one day post-processing in jams with LMAP followed by samples with LMP and HMP. Storage for 6 months brings along additional dramatic losses reported to the values recorded one day post-processing as follows: TMA (31-56%), TP (29-51%) and FRAP (20-41%). Also, both processing and storage resulted in significant increases in PC (%). The pectin type and dosage are very influential factors for limiting the alterations occurring in response to processing and storage. The best color retention and the highest TMA, TP and FRAP were achieved by LMAP, followed by LMP and HMP. Additionally, a high level of bioactive compounds in jam could be related to a high dose of pectin. LMAP to a level of 1% is the most indicated to provide the highest antioxidant properties in jam.

Conclusions

The retention of bioactive compounds and jam color stability were strongly dependent on the pectin type and dosage. By a proper selection of pectin type and dose could be limited the losses recorded in response to processing and storage.

Effect of temperature and some added compounds on the stability of blood orange marmalade

Jams and marmalades are often wrongly believed to be stable products, as the degradation of pigments such as anthocyanins, browning reactions, and the formation of sugar degradation products may occur during storage. The paper aims at studying some of the degradation reactions occurring in blood orange marmalade stored at 20 °C and 35 °C. The addition of natural (tea extract) and naturally occurring (ascorbic acid, cysteine, gallic acid) compounds to marmalade was addressed at investigating the possible effect on retarding such phenomena. Results highlight the dependence of anthocyans and 5-hydroxymethyl-2-furaldehyde (HMF) levels on the storage temperature. Marmalades added with cysteine, unlike the samples added with phenol compounds, showed higher anthocyans and lower HMF levels just after processing, together with a reduced anthocyan loss kinetics and a slowdown of HMF formation during storage at both temperatures.

PRACTICAL APPLICATION

Transformation of blood oranges into marmalade represents an alternative to fresh market in periods when the high availability of the citrus causes the collapse of prices. Blood orange marmalade is characterized by a high nutritional value, however, it is not widely distributed yet. Its storability is limited by color and organoleptic changes that influence consumers' acceptance. The optimization of blood orange marmalade preparation could help producers improve storability and widen distribution.

Food caramels: a review

Caramel, defined as coloring agent and as an antioxidant, is being used in several kinds of food products. It has been classified into 4 classes to satisfy the requirement of several food and beverage systems. The variation in its consistency owing to its basic content of milk solids, sugars, and fat has been studied. Several methods have been found to estimate the amount of color provided by caramel in food products. Various formulations have been cited for the production of caramel by eradicating the frequent areas of problems during its processing. Caramel has been used as a synthetic colorant replacer in the baking and beverage industries. Researchers have aimed to ascertain the contribution to the antioxidant activity of some caramel-containing soft drinks. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has established an acceptable daily intake (ADI) of Class I caramel color as "not specified"; that of Class II as 0-160 mg/kg body weight; that of Class III as 0-200 mg/kg body weight; and that of Class IV as 0-200 mg/kg body weight. This paper is an overview of the classification, physicochemical nature, formulations, coloring properties, antioxidant properties, and toxicity of caramel in different food systems.

Jam processing and storage effects on blueberry polyphenolics and antioxidant capacity

Fresh blueberries were processed into sugar and sugar-free jams and stored for 6 months at 4 and 25 degrees C. The jams were analyzed immediately after processing and over 6 months of storage for polyphenolic content, percent polymeric color, and antioxidant capacity. Processing resulted in losses of anthocyanins, procyanidins, chlorogenic acid, and ORAC in both jam types, but flavonols were well retained. Marked losses of anthocyanins and procyanidins occurred over 6 months of storage and were accompanied by increased polymeric color values. Chlorogenic acid levels also declined during storage, but flavonols and ORAC changed little. Jams stored at 4 degrees C retained higher levels of anthocyanins, procyanidins, and ORAC and had lower polymeric color values than jams stored at 25 degrees C. Sugar-free jams retained higher levels of anthocyanins and had lower polymeric color values than sugar jams late during storage. Blueberry jams should be refrigerated to better retain polyphenolics and antioxidant capacity.

Influence of postharvest processing and storage on the content of phenolic acids and flavonoids in foods

The review is based on the evaluation of electronically collated data published between 2002 to June 2006. It is based on 325 references dealing with the following subclasses of phenolic compounds: hydroxycinnamic and hydroxybenzoic acids, chalcones, flavanones, flavones, flavonols, monomeric flavanols and anthocyanins. Only publications dealing directly with the effects of storage and postharvest processing on the phenolic acid and flavonoid contents of foods were considered. The expectation that the structural diversity even within each subgroup, and the number of different procedures and of different parameters would make finding homogenous tendencies unlikely, has, in most instances, been confirmed. By adding a database Excel table combined with a focused and unified evaluation, specific additional information was rendered accessible and concise. It holds true for most of the subclasses in question that the effect of storage and food processing on the polyphenol content is negligible in comparison to the differences between different varieties of plants. Variety dependence must always be considered, for all classes of compounds.

Properties of extracts from defatted rice bran by its subcritical water treatment

Defatted rice bran was extracted with water and subcritical water at 50-250 degrees C for 5 min. The highest extract yield was achieved at 200 degrees C, at which the maximum amounts of protein and carbohydrate were also obtained. The total phenolic and furfural contents, radical scavenging activity, and antioxidative activity for the autoxidation of linoleic acid increased with increasing treatment temperature. The bran extracts exhibited emulsifying activity except for the extract prepared at 250 degrees C, which was concomitant with the disappearance of its high-molecular-mass substances. The extract prepared at 200 degrees C also had the highest emulsion-stabilizing activity.