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Effects of Food Processing, Storage, and Cooking on Nutrients in Plant-Based Foods
Published in Nicole M. Farmer, Andres Victor Ardisson Korat, Cooking for Health and Disease Prevention, 2022
The nixtamalization process changes the concentrations of several nutrients found in corn. For instance, masa made with nixtamalized corn retained about 64% of its original carotenoid content compared to the original raw material (Trono, 2019). The alkaline environment during nixtamalization results in substantial polyphenol losses (54%–66% of total polyphenols and almost all of anthocyanins) (Suri & Tanumihardjo, 2016). Nixtamalization tends to decrease the overall concentration of most vitamins. For instance, levels of thiamin, riboflavin, and niacin decrease by 30%–50%. However, nixtamalization increases the bioavailability of niacin by releasing it from cell wall materials (Suri & Tanumihardjo, 2016). Nixtamalization results in small decreases in concentrations of iron, magnesium, phosphorus, and copper, but it substantially increases its calcium content because of the calcium contributions of limewater (calcium hydroxide) (Suri & Tanumihardjo, 2016).
Grains
Published in Christopher Cumo, Ancestral Diets and Nutrition, 2020
Hominy, whose preparation leveraged an intuitive understanding of chemistry, fed Mesoamerica. Its production necessitated immersing corn kernels in alkaline water. Such liquid, having a pH over 7—the number signifying neutrality—may be obtained by dissolving ashes in water. Another option is calcium hydroxide [Ca(OH)2], known as limewater, whose pH is also above 7. Numbers over 7 signify bases, whereas those below 7 are acids. The greater the pH, the more caustic the solution. Alkaline water is caustic enough to loosen the husk, whose removal increases digestibility of nutrients and calories. For example, the solution separates vitamin B3 from indigestible hemicellulose, permitting the vitamin’s absorption. Greater availability of B3 and amino acid tryptophan protects against pellagra. Husk’s removal eases grinding the rest of the kernel and forming dough. Lacking gluten, the dough does not leaven and is not hominy: the remains of kernels after alkaline water treatment, a process known as nixtamalization. Nixtamalization removes some bran, raising the issue of whether hominy is a whole grain. The USDA categorized nixtamalized corn as whole grain, specifying tortillas made from it as such but omitting reference to hominy.149 Boston, Massachusetts’ Whole Grains Council likewise withheld judgment about hominy.
The nineteenth century
Published in Michael J. O’Dowd, The History of Medications for Women, 2020
At the close of the nineteenth century Sidney Ringer, professor of the principles and practices of medicine at University College Hospital, London, summarized the materia medica for women in his ‘Index to Diseases’. Of interest is the new reliance on chemicals and the reduced number of plant medications, in contrast to previous centuries. Limewater, mentioned by both Samuel Bard and Sidney Ringer, referred to a suspension of calcium hydroxide in water. The lime was obtained from slaked limestone (calcium carbonate).
Betel nut: the prevalence of a carcinogenic substance as a social food—a study based on Xiangtan, Hunan province, China
Published in Journal of Substance Use, 2023
Hong Wen, Hong Zheng, Lifang Li, Fengshan Li, Sheng Mingke
The BN chewing habit amongst the Xiangtan public has also promoted the development of the BN processing industry in the local area. In the Qing Dynasty, the local BN industry first formed a series of management systems. Traditionally, people either chew area nuts directly, wrap them in leaves, or dip them in lime water before chewing (Singh et al., 2020). However, since the Xiangtan area is far from the origin of betel nut cultivation, these ways of chewing are challenging to store and transport BN, and it is even more difficult to commercialize and sell them. From the Guangxu period to the Republic of China, the social turmoil and economic downturn inspired a series of improvements in technology, ingredients, and BN sales, which greatly broadened its acceptance amongst the public. Before the liberation period, BN had been transformed into localization in the Xiangtan area and became a necessity widely used by the public in various festivals, social activities, and ceremonies.
Assessment of an anti-scale low-frequency electromagnetic field device on drinking water biofilms
Published in Biofouling, 2018
F. Gosselin, L. Mathieu, J.-C. Block, C. Carteret, H. Muhr, F. P. A. Jorand
The Carbonate assays (with tap water oversaturated with respect to CaCO3 and exposed to the EMF) were performed with reactor R2*. For example, at day 80 the cell densities for both SS and PVC coupons were ∼107, 3.1–3.6 × 106, and 1.3–2.1 × 105 cm−2, for total cells, membrane-damaged cells, and CFU, respectively (Figure S5). In comparison with reactors R1* or R3*, without lime water, there were no significant differences: the cell densities for both SS and PVC coupons were 1.1–1.8 × 107, 0.8–1.3 × 107, and 1–2 × 105 cm−2, for total cells, membrane-damaged cells and CFU, respectively (Figures S4, at day 90). In this assay with CaCO3 oversaturated water, the higher pH (∼9) resulting from the addition of lime water had no negative effect on the bacterial density. The Δbiofilm between Carbonate and Control and Δbiofilm between Carbonate and Assay was calculated (Figure 4b and c). Again, the results seemed to be slightly influenced by the reactor (higher values with R3). However, here also the statistical analysis indicates that no significant differences can be assigned between the reactors exposed or not to EMF and fed or not with oversaturated water (Table 2). Therefore, neither the EMF treatment nor the presence of CaCO3 was found to significantly affect the biofilm accumulation on SS and PVC coupons.