Nutritional Composition and .ALPHA.-Glucosidase Inhibitory Activity of Five Chinese Vinegars

Abstract

Vinegar has been consumed as a food condiment and preservative in the Chinese diet for more than 3,000 years. There are currently at least 14 main types on the market for different raw material and processing technologies, including Zhenjiang aromatic vinegar (ZAV), Shanxi aged vinegar (SAV), Jiangzhe rose vinegar (JRV), and Baoning bran vinegar (BBV) 20 . Among these, ZAV and SAV are the most famous and mainly popular in the south and north of China, respectively.ZAV generally employs rice and rice bran as major raw materials, whereas SAV uses minor grain crops (sorghum, oat, and tartary buckwheat) as the main raw materials with a very large dosage of great koji (composed of wheat bran and pea, and comprising around half the raw materials). These minor grain crops are traditionally treasured as health foods for their special nutritive value and functional activity. The manufacturing flowcharts for both types of vinegars are shown in Fig. 1. With respect to processing procedures, ZAV employ liquid-state fermentation in saccharification and alcohol fermentation, and solid-state fermentation in acetic acid fermentation respectively, while the entire SAV process takes place in the solid state. In particular, ZAV has only an aging process of less than three months without a roasting process following acetic acid fermentation, while SAV has a 6-day fuming (roasting) period and at least 18 months of aging. These processes endow SAV with increased concentrations of organic acids, flavor and nutrients due to chemical and enzymatic reactions 20 , which explains the great variation in quality and nutri- AbstractShanxi aged vinegar (SAV) and Zhenjiang aromatic vinegars (ZAV) are representative of minor grain crop vinegars in the north of China and rice vinegars in the south, respectively. The nutritional composition of five Chinese vinegars, including three typical SAV and two ZAV, were determined. Investigations showed that these vinegars differed from each other in terms of the organic acid content (75.32-175.95 g/L), and amino acids (1215.9-2878.8 mg/100 g). SAV, especially oat vinegar, were 9-40, 2-211, 4-210, 1-3 and 1-1.5 times higher than ZAV in calcium, phosphorus, iron, zinc, and manganese contents, respectively. Nicotinic acid, nicotinamide, phenolics, alkaloids and saponin in these vinegars were shown to be 2.33-37.83 mg/100g, 1.23-35.03 mg/100g, 382.4-4518.1 μg/mL, 0.088-1.209 mg/mL, and 0.183-0.662 mg/mL, respectively. SAV seemed relatively better than ZAV in terms of essential amino acids, minerals and vitamins and also exhibited strong α-glucosidase inhibitory activities. These results suggested that both types of typical Chinese vinegars could be used as health foods, despite their different raw materials and processing technologies.

Vinegar: functional aspects

“…Gu et al (2012) found that the consumption of Chinese white rice vinegar helped in controlling blood glucose; Fan et al (2011) obtained similar results, verifying inhibitory activity of α-glucosidase, which can be useful for diabetics. Other studies have demonstrated benefits across the immune system (Hashimoto et al, 2013) and anti-hypertensive effect (Kondo et al, 2001).…”

“…Given the importance of beta cells and hepatocytes protection in the development of diabetes and the importance of glycemic control, vinegar can be considered a dietary supplement promising for diabetics. Fan et al (2011) studied five different Chinese vinegars, in order to characterize their composition and determine the inhibitory activity of α-glucosidase. On laboratory analysis, it was observed a strong inhibitory activity of α-glucosidase, an enzyme that slows carbohydrate digestion in the intestinal tract, which indicates application to studies on diabetics.…”

“…The Chinese also already knew it, as they use vinegar for more than 3000 years; in addition to flavoring and preservative, it has been used for medicinal purposes in traditional Chinese medicine (Fan et al, 2011).…”

Determination of rheological property and its effect on key aroma release of Shanxi aged vinegar

“…Total polyphenol content ranged from 0.88 to 25.94 g/L, and the highest level was found in SAV with 20 ageing years. The phenolic content of SAV was comparable to that of wine and other Chinese vinegar, and ranged from 0.38 to 4.51 g/L (Budak and Guzel-Seydim 2010; Fan et al 2011). In particular, the content of glucose, total polyphenol, NaCl, acetic acid, lactic acid and values of pH, density and o Bx of SAV all increased with ageing time.…”

Health Promoting Properties of Cereal Vinegars

“…Cereal vinegars present an inhibition effect on α-glucosidase, and therefore may be used to prevent or medically treat type II diabetes by reducing the absorption of dietary carbohydrates. Fan et al [ 23 ] studied Chinese cereal SAVs (SoV, OaV and TBV) and ZAVs (Zhenjiang Hengshun vinegar, ZHV, and Liubiju rice vinegar, LRV) and determined an in vitro inhibitory activity over α-glucosidase. More specifically, SoV presented the highest inhibition followed by OaV and TBV.…”