Tofu isoflavones

Isoflavonoids Soybeans, tofu, isoflavone supplements Linear (+) THAP, DHB 318... 

The effects of phytoestrogens on cognitive function have also been investigated in humans. However, the results of these studies were inconclusive. White et al, (2000) concluded that tofu consumption in midlife was associated with diminished cognitive function later in life. In contrast. File et al. (2001) reported that short-term consumption of high levels of isoflavones (100 mg/day) may improve memory. 

Before 1990 the composition of isoflavones in soy foods was thought to be largely determined by whether the food had been fermented. Fermented foods (e.g., miso and tempeh) contain the unconjugated isoflavones agycones, while non-fermented food (e.g., tofu, soy flower, and soy milk) contain the conjugated glucoside. Subsequent experiments have demonstrated that fermentation of soy decreased the isoflavone content of the food product, but increased the urinary isoflavonoid recovery, suggesting that fermentation increases availability of isoflavones in soy (Slavin et al., 1998). 

Isoflavones Daidzein Genistein Glycitein Soy flour, soybeans boiled, tofu, soy milk... 

Epidemiological studies (Aldercreutz et al., 1991 Aldercreutz, 1998) indicate that consumption of tofu and other soy foods may be associated with the low incidence of breast cancer in Japanese women. This discovery has led numerous researchers in recent years to search for the biochemical components in soybean that are responsible for the cancer risk-lowering effect. Aside from the potential cancer prevention effect (Wu et al., 1996 Cline and Hughes, 1998 Griffiths et al., 1998 Messina and Bennink, 1998 Stephens, 1999), isoflavones also have been found to have other potential health benefits, including heart disease prevention (Anthony et al., 1998), bone mass density increase to prevent osteoporosis (Anderson and Camer, 1997) and the reduction of postmenopausal syndromes in women (Knight et al., 1996). 

Table 10.10. Fraction Weight, Moisture and isoflavone Contents in Soymilk and Tofu Processing (Wang Murphy, 1996) ...

Other soy protein products include dried soy milk and tofu (see the Chapter Food Use of Whole Soybeans), as well as mixtures of SF, SPC, or SPI with milk or egg protein, gelatin, or other components for specific functional applications. Extruder-texturized fburs and concentrates and spun fiber isolates, which resemble meat in appearance, may be made at the point of use but usually are supplied in bulk from strategically located production facilities. Edible co-products of soy protein ingredient manufacture include the hulls and the cotyledon fiber (cell walls) from SPI or soymilk production. The extract by-product from SPC may be used as the feedstock for isolating isoflavones. 

Isoflavones may be found in small amounts in soy-based infant formulas [10]. Isoflavones are found in whole soybeans and products including tofu, tempeh, and soy milk. Isoflavones are classified as both phytoestrogens (plant estrogens) and selective estrogen receptor modnlators. The phytoestrogenic effects of isoflavones have led to the use of soy foods and isoflavone supplements as alternatives to conventional hormone therapy. However, studies have found no long-term complications associated with isoflavones in infants fed soy-based formulas [10,17]. 

Isoflavones (2) have usually been found as small amount phytochemicals from the legumes, grains and vegetables, and their processed foods such as traditional tofu and Indonesian tempeh which is a traditional soy product originally from Indonesia [Indonesian tempeh is made by a natural culturing and controlled fermentation process that binds soybeans into a cake form of similar to a very firm vegetarian burger patty], miso, natto, soya milk, bean curds and bean sprouts. 

Dietary isoflavones come from traditional soy foods (SF), modem soy products (a new source of isoflavones in Western populations, e g., soy buigers, soy yoghurts), and commonly consumed foodstuffs which contain soy flour or soy protein isolates (SPI). The isoflavone content of traditional SF, e g., miso, soy milk, tofu, and modem soy products vary... 

Isoflavones, such as genistein (see Fig. 1) and daidzein, are found in Just a few botanical families, e.g., soy. Up to 3 mg/g of genistein and daidzein and their (1 glycosides are present in soybeans. Information on isofiavone content in soy products, such as soy milk, tofu, and fermented products such as miso, soy sauce, and tempeh, is given by Coward [92] and Wang [93]. 

Japanese women and women of Japanese origin living in Hawaii but who consume a diet similar to the traditional Japanese diet (rich in soy products) have a low breast cancer incidence and mortality. Women in the Far East who have low rates of breast cancer are thought to consume approximately 30-50 times more soy products than women in the United States. A case-control study in Singapore found that premenopausal women who consumed 55 g of soy per day had a 50% reduced risk of breast cancer compared to women who infrequently consumed soy foods. A high intake of miso soup has been associated with a reduced risk of breast cancer in Japanese women. In prospective trials, a trend toward an inverse association between intake of tofu and subsequent risk of breast cancer and an inverse association between intake of miso soup and development of breast cancer have been found. However, a large prospective study in Japan did not show any effect of soy consumption on breast cancer risk, although this may be because dietary intake was studied in adult women rather than in children or adolescents. A number of studies in rodents have indicated that a protective effect of a soy isoflavone-rich diet may... 

---