The High Content of Quercetin and Catechin in Airen Grape Juice Supports Its Application in Functional Food Production

Abstract

Ensuring healthy lives and well-being constitutes one of the Sustainable Development Goals of the UN 2030 agenda. Consequently, research into how natural products may promote health is essential for the new generation of nutraceuticals and functional foods that are in high demand today. Grape juice is a natural foodstuff composed of water, sugars, minerals, vitamins and a wide array of polyphenols. Polyphenols are bioactive compounds of great interest due to their antioxidant properties and benefits to health, supporting antimicrobial, anti-aging, and anticarcinogenic activity. The majority of grape juice produced in the world is used for the production of wine, although a small part is used in the food industry, mainly in baby food and sports drinks. The aim of this work is to determine the polyphenol content in the natural and concentrated juice of Airen grapes, the main white grape variety produced in Spain. For this, fresh juices from five grape varietals (Airen, Sauvignon Blanc, Gewürztraminer, Verdejo and Tempranillo) and concentrated Airen juice were analyzed and compared. Results showed similar contents of phenolic acids and stilbenes in all grape varietals studied, although the Airen variety demonstrated a higher concentration of two flavonoids: quercetin and catechin. It can be concluded that the grape juice concentration process negatively affects the stability of these compounds, causing a reduction in the polyphenol content that ranges between 54–71%, with the exception of quercetin and catechin.

Elaboration of an organic beverage based on grape juice with positive nutritional properties

“…Grape juices consist of water (81%–86%) and a high concentration of sugars (glucose and fructose), with high acidity owing to the existence of organic acids that balance the sweet and sour tastes. They present small amounts of minerals, vitamins, and other phenolic aromatic compounds that provide sensory characteristics of grape juices (color, taste, and flavor) (Cosme et al., 2018 ; Dutra et al., 2021 ; García‐Martínez et al., 2021 ). Among the phenolic compounds found in grape juice are flavonols (kaempferol, quercetin, and myricetin), flavanols (catechin, epicatechin, and procyanidins), anthocyanins (malvidin, cyanidin, delphinidin, petunidin, peonidin, and pelargonidin), phenolic acids, and the stilbene resveratrol (Burin et al., 2010 ; Lima et al., 2014 ; Nadeem et al., 2018 ; O’Byrne et al., 2002 ; Xia et al., 2010 ).…”

“…Consumption of grape juice has positive health advantages due to effective antioxidant, anticarcinogenic, antibacterial, antidiabetic, antiaging, and anti‐inflammatory activities as well as cardioprotective, hepatoprotective, and neuroprotective effects (Nadeem et al., 2018 ; Wu et al., 2021 ), which develop endothelial function, increasing the antioxidant capacity of serum and low‐density lipoproteins, minimizing native plasma protein oxidation, and reducing platelet aggregation (Burin et al., 2010 ; Dávalos et al., 2005 ). Moreover, studies have shown the beneficial effects of resveratrol and quercetin in the treatment of cancer and cardiovascular diseases (García‐Martínez et al., 2021 ).…”

Biogenic Phytochemicals Modulating Obesity: From Molecular Mechanism to Preventive and Therapeutic Approaches

“…Some other flavonoids and genistein increase the HDL (high-density lipoprotein) and decrease the BMI (body mass index). Naringin and berberine reduce the hypercholesterolemic level, decrease the blood lipid and quercetin molecules, and increase the blood HDL [ 134 , 135 ]. Alkaloid with antiobesity property isolated, synephrine from Citrus aurantium , nuciferine from Nelumbo nucifera , piperine and piperlongumine from Piper nigrum .…”

Contribution of Grape Juice to Develop New Isotonic Drinks With Antioxidant Capacity and Interesting Sensory Properties

“…The United States, Spain, China, Italy, France, Turkey, and Chile are the top producers of grape juice ( 41 ). Grape juice contains water, high concentration of sugars and organic acids ( 42 , 44 , 45 ), and minerals, phenolic compounds, and other nutrients such as vitamins, proteins, fatty acids, and amino acids ( 46 , 47 ). Carbohydrates are found in the form of fructose and glucose ( 48 ).…”