Maisgriess, Vollkorn (roh?, bio?)

Narratives Review

"Whole grains shall consist of the intact, ground, cracked or flaked caryopsis, whose principal anatomical compo-nents—the starchy endosperm, germ, and bran—are pres-ent in the same relative proportions as they exist in the intact caryopsis."

"Soaking of corn in water with lime (calcium oxide), called nixti-malization, improves the availability of certain essential amino acids and releases the niacin from niacytin, which are both important for the prevention of niacin deficiency (pellagra)."

"Some websites and authors suggest that flour milled between stones (which has neither been separated nor recombined) de-livers more nutrients than grains crushed between metal rollers. This theory is based on the supposition that grains crushed by stones would not reach a temperature as high as grains crushed by steel rollers. However, this is only true if the grinding is very slow and labile components are not exposed to temperatures that enhance vitamin loss (56).A study comparing roller, plate, hammer, and stone mills showed that the highest temperatures were generated when grinding wheat between stones, with temperatures reaching as high as 90°C. In contrast, roller mills reached temperatures of 35°C, and plate and hammer mills reached intermediate temperatures within this range."

"Whole grain flours are produced using different milling tech-niques. The majority of whole grain flour is produced using modern milling techniques, usually with steel rollers, through processes in which a batch of grain is separated into multiple millstreams, sifted, and then recombined. In other cases con-stituent millstreams are purchased and combined by a supplier or end user to achieve a reconstituted whole grain flour or meal that has the desired functional, food safety, and nutritional prop-erties. In a very small number of cases whole grain flours are stone-ground, with the grain kernels crushed between rotating stones. The techniques of separating, sifting, and recombining millstreams have been practiced for centuries."

DOI: 10.1094/CFW-60-3-0130

Study: weak evidence

Narrativer Review in wissenschaftlichem Journal

"Bioactive peptides can be found in abundance in corn, having very diverse biological effects that include analgesic, opioid and antihypertensive activities. Other compounds with biological activity found in pigmented corn are resistant starches, some fatty acids, phytosterols, policosanols, phospholipids, ferulic acid and phlobaphenes, as well as a great variety of vitamins, elements and fibers."

"The consumption of corn and other whole-grain products has been linked to the reduced risk of chronic diseases including cardiovascular disease, type 2 diabetes, obesity, some cancers and with the improvement of digestive tract health."

"Phenolic compounds and anthocyanins are some of the most studied and representative compounds in these grasses, with a wide range of health properties, mainly the reduction of pro-oxidant molecules. Carotenoids are a group of molecules belonging to the terpenic compounds, present in a large number of pigmented corn breeds, mainly the yellow ones, whose biological activity incorporates a wide spectrum."

"Currently, corn is grown in different shapes and kernel shades, such as blue, black, cherry, purple and red, known as pigmented corn. Pigmented corns are those that, unlike white corn, contain phenolic and/or carotenoid compounds (terpenic compounds) in one or more of the kernel structures: pericarp, aleurone and/or endosperm. These terpenic and phenolic compounds (mainly anthocyanins) give the kernels shades ranging from blue–violet to almost black, to red."

"Pigmented corns contain anthocyanins in different ranges, depending on the breed and variety, which give them colorful colors, as well as carotenoid compounds (carotenes and xanthophylls). These phytochemical compounds give pigmented corn a nutraceutical advantage over white and even yellow corn, despite the latter’s high carotenoid content. Anthocyanins can be found in the pericarp and aleurone, or only in one of them. Pigments have also been observed in its endosperm. The location of the pigments is of great importance because it is an indication of the amount of pigments that can be extracted and allows one to decide on the best way to use these compounds without degrading them. Other groups of compounds found in pigmented corn, although in smaller quantities, are free phenols, non-anthocyanidic flavonoids, ferulic acid, lutein, zeaxanthin, cryptoxanthin, alpha and beta carotenes, among others."

"Cereals, including corn, are the most important source of ferulic acid, derived from cinnamic acid (intake ranges from 0.092 to 0.32 g). ... Ferulic acid has low toxicity and possesses many physiological functions, including anti-inflammatory, antimicrobial, anticancer (e.g., lung, breast, colon and skin cancer), antiarrhythmic and antithrombotic activity. It also demonstrated anti-diabetic effects and immunostimulant properties, as well as reduced nerve cell damage, and may help repair damaged cells."

Table 2 (neben blauem und rotem Mais, enthalten auch white und yellow corn Phenole, Ferulasäure und Anthocyane)

"Anthocyanins have demonstrated antioxidant potential in both in vitro and in vivo studies and the consumption of anthocyanin-rich foods has been linked to lower risks of chronic diseases."

"The benefits of pigmented corn on human health go beyond its high antioxidant capacity, as many of its compounds can act as transcription factors in the regulation of a large number of genes related to the coding of antioxidant enzymes, the regulation of signaling pathways related to aging, insulin resistance, obesity, inflammation, oxidative stress, among others. Likewise, pigmented maize has the potential to regulate the intestinal microbiota and its metabolites, as well as to chelate metal ions and toxins from the diet."

DOI: 10.3390/biom14030338

Study: weak evidence

Nährstofftabellen.

Website

Narratives Review in wissenschaftlichem Journal

"Human clinical trials, epidemiological studies, and some animal studies have implicated that regular consumption of corn and its derived whole grain products is associated with reduced risk of developing chronic diseases such as cardiovascular disease, type 2 diabetes, and obesity. The high amylose content in corn contributes to the digestive health by its nature of resistance to digestion thus bringing bioactive compounds to the colon. Therefore, dietary modifications of increasing corn and other whole grain consumption is a practical strategy to optimize health and reduce the risk of chronic diseases."

"Corn nutrients and phytochemicals include vitamins (A, B, E, and K), minerals (Mg, P, and K), phenolic acids (ferulic acid, coumaric acid, and syringic acid), carotenoids and flavonoids (anthocyanins), and dietary fiber."

"The major components of corn kernel include endosperm, germ and bran, and each of them contains a different phytochemical profiles. Along with the health promoting compounds such as amylase in corn endosperm, a wide range of phytochemicals such as total phenolics and phenolic acids (vannilic acid, syringic acid, courmaric acid, ferulic acid and caffeic acid) are found in corn bran and germ fractions at high concentrations. Adom &Liu et el. discovered that the majority phytochemicals in corn with beneficial effects on human health are presented in the bran and germ fractions and not the endosperm, with about 87% of total phenolic content (TPC) presented in the bran and germ fractions. Thus, corn flour with ground germ, endosperm and bran contains higher bioactive compounds than refined cornstarch and refined corn oil."

"Like many other grain products, phytochemicals in corn are also distributed mainly in the kernel and bran. Phytochemicals composition varies among different type of corn. Carotenoids are concentrated in yellow and red corn, anthocyanins are concentrated in red, blue, purple and black corn, and phytosterols are concentrated in kernel part of corn."

"Corn has the highest total antioxidant activity (181.4 ± 0.86 μmol of vitamin C equiv/g of grain) among all common grains such as rice, wheat and oats. Phytochemicals are the major contributors to the total antioxidant activity in corn. Flavonoids and ferulic acids contribute to the total phenolics in corn and are directly related to the total antioxidant activity, 87% of them were in bound form. Thermal processing increases the antioxidant activity of sweet corn by releasing bound form phytochemicals. Dewanto et al. firstly reported that thermal processed sweet corn had higher antioxidant activity than the unprocessed sweet corn."

DOI: 10.1016/j.fshw.2018.09.003

Study: weak evidence

Experimentelle Lebensmittel-/Verarbeitungsstudie in wissenschaftlichem Journal

"The proximate and mineral composition of corn and its products provides substantive nutritional information on corn, for effective guide on dietetics. The data from the study indicates that eating whole corn which is high in carbohydrate and protein is more beneficial as compared to flours where removal of the bran or germ resulted in removal of the vital component of the maize."

"Hence, our study supports preferential use of corn and its products for better human health and also suggests the inclusion of corn in the regular diet due to its higher phenolic acid content and xanthophylls lutein and zeaxanthin which are antioxidants and constitutes for the macular pigment. Hence, Corn is a vital food source for much of the world’s population and represents a vehicle for sustenance and deficiency intervention and there are several industrial processes which can generate a wide variety of maize products to meet consumer’s habits and preferences."

"The TPC was high in raw dent corn and steamed dent corn with 14.53 mg GAE/100 g and 12.61 mg GAE/100 g respectively and it was less in corn flour raw (1.26 mg GAE/100 g) and boiled (1.16 mg GAE/100 g) which could be due to the degradation of bioactive compounds and absorption of water during boiling resulting in the dilution of active compounds (Podsedek 2007)."

"Lower levels of zeaxanthin was reported in precooked corn flour when compared to canned corn (De Oliveira and Rodriguez-Amaya 2007) similar decrease was observed in our study in the corn flour when compared to other corn products and there was significant decrease between the raw and the boiled corn flour."

"Lutein concentration was highest in yellow prepared and processed corn (394.38 µg/100 g in raw and 313.66 µg/100 g in steamed) which was also reported by de la Parra et al.(2007), while it was not traceable in corn flour which can be attributed to the fact that corn flour is a processed product obtained from milling the endosperm of the maize germ after the removal of germ and outer layer which results in the loss of nutrients while yellow dent corn is a fresh product which was a prepared product."

Table 4: carotenoids / Table 5: total polyphenolic content (z.B: 4-OH Benzoic acid, Vanillic acid, Syringic acid)

DOI: 10.1007/s13197-017-2547-2

Study: weak evidence

"Süsser Mais, Maismehl und andere Maisprodukte üben eine schützende Wirkung auf die Darmschleimhäute aus. Weil Mais kein Gluten enthält, wird er auch von angegriffenen Verdauungssystemen gut vertragen."

"Untergewicht im Allgemeinen: Mais in jeder Form wird zur Gewichtszunahme empfohlen."

Book

"Die Maisallergie betrifft Kinder und Erwachsene gleichermassen und kommt leider immer öfter vor. Wer nach dem Verzehr von Mais oder Maisprodukten ein Jucken im Mund oder das anschwellen von Lippen und Zunge bemerkt könnte eine Allergie gegen Mais entwickelt haben. Mais wird fast überall auf der Welt angebaut und gegessen, in unzähligen Produkten kommt Mais vor, zb. in Salaten, Cornflakes, Popcorn, Erdnussflips, Maisstärke, Maismehl. Mais wird auch zu Oel verarbeitet und bei Pflegeprodukten oder zum Kochen eingesetzt. Ja selbst Bier und Schnaps werden aus Mais gebraut und können Allergien auslösen."

"Eine Allergie auf Mais-Pollen ist relativ selten, aber es können durchaus Kreuzreaktionen vorkommen, zumeist kommen hierfür Gräser wie Weizen, Roggen, Weidelgras oder Hafer in betracht. Allergische Kreuzreaktionen auf andere Lebensmittel kommen sehr selten vor."

Website

Doppelblinde, placebokontrollierte Provokationsstudie (Interventionsstudie)

"Maize is a cause of IgE-mediated allergic reactions to foods in adults and children."

DOI: 10.1111/j.1365-2222.2008.03094.x

Study: strong evidence

Experimentelle Laborstudie in wissenschaftlichem Journal

"Zeaxanthin, along with its isomer lutein, are the major carotenoids contributing to the characteristic colour of yellow sweet-corn. From a human health perspective, these two carotenoids are also specifically accumulated in the human macula, and are thought to protect the photoreceptor cells of the eye from blue light oxidative damage and to improve visual acuity."

DOI: 10.1016/j.abb.2015.01.015

Study: weak evidence

Experimentelle Laborstudie in wissenschaftlichem Journal

"The total phenol and anthocyanin contents correlate with the observed antioxidant capacity. The most biological active corn samples were the blue color while the least actives were the red ones. The results show that the studied blue corn samples are good sources of antioxidant and antimutagenic compounds, which could use to develop products that contribute to human health."

"Pigmented corn has been proposed as a functional food considering that is rich in secondary metabolites that displayed biological activities. It is known that the purple and red colors of maize are due to the flavonoid content while the yellow color is produced by the presence of carotenoids. These compounds are mainly contained in the pericarp and aleurone layer of the corn. Several anthocyanins, flavonols and carotenoids have been identified in samples of pigmented corn, such as: cyanidin, pelargonidin, peonidin glucosides; protocatechuic, vanillic, p-coumaric, ferulic acids; quercetin and hesperetin derivatives, among others"

DOI: 10.1007/s13197-019-03671-3

Study: weak evidence

Schicksalhaft aber wurde für den Mais die enorme Nachfrage als Futtermittel. Die schuf extreme konventionelle Monokulturen, welche für die Umwelt und sogar den Mais selbst schädlich wurden: ... ohne Fruchtwechsel werden Maisfelder zu Schädlingsparadiesen und verlangen Mengen von Pestiziden u.a. gegen den berüchtigten Maiszünsler.

Ihre verschiedenen Sorten von Gen-Mais sind gegen die Pestizide resistent und werden als besonders widerstandsfähig verkauft. Fatalerweise allerdings brauchte es stets nur wenige Jahre, bis die Einbaugifte gegen resistente Schädlinge nichts mehr ausrichteten oder sogar ...

Längst wurden auch in anderen Regionen alte Sorten verdrängt...

Zum Problem wurde beim energiereichen Mais längt auch die Nutzung für die Herstellung von Bioethanol bzw. von Biogas.

Als garantiert gentechnikfreier Mais hat Bio-Mais...

Book

Experimentelle Laborstudie in wissenschaftlichem Journal

"Phytic acid is known as a food inhibitor which chelates micronutrient and prevents it to be bioavailabe for monogastric animals, including humans, because they lack enzyme phytase in their digestive tract. Several methods have been developed to reduce the phytic acid content in food and improve the nutritional value of cereal which becomes poor due to such antinutrient. These include genetic improvement as well as several pre-treatment methods such as fermentation, soaking, germination and enzymatic treatment of grains with phytase enzyme. Biofortification of staple crops using modern biotechnological techniques can potentially help in alleviating malnutrition in developing countries."

"In cereal grains, rice and wheat, it is found in bran fraction such as aleurone layer and pericarp, in corn it is seen in endosperm (O’Dell et al. 1972). "

DOI: 10.1007/s13197-013-0978-y

Study: weak evidence

Humanstudie in wissenschaftlichem Journal (randomisierte, kontrollierte Crossoverstudie, aber kleine Stichprobe = 5)

"Phytic acid reduction in cereal grains has been accomplished with plant genetic techniques. These low-phytic acid grains provide a strategy for improving the mineral (eg, zinc) status in populations that are dependent on grains, including maize (Zea mays L.), as major dietary staples."

"Substitution of a low-phytic acid grain in a maize-based diet is associated with a substantial increase in zinc absorption."

"In many populations, zinc deficiency has been attributed to an impaired bioavailability of dietary zinc (5). Phytic acid (myo-inositol-1,2,3,4,5,6-hexa-kis-phosphate) is widely regarded as the principal dietary factor that impairs zinc bioavailability (5–9). Indeed, current World Health Organization calculations of dietary zinc requirements vary 3-fold depending on the phytic acid content of the diet (10). Phytic acid is the storage form of phosphorus in seeds (11) and typically represents 1–2% of seed dry weight. Cereal grains, including maize (11), are among those foods of vegetable origin that have the highest content of phytic acid."

"Hence, persons whose diets are dependent on maize as a major food staple appear likely to be at risk of zinc deficiency"

DOI: 10.1093/ajcn/76.3.556

Study: strong evidence

"Die Pellagra ist eine Hypovitaminose, die meist in Folge einer Mangelernährung auftritt. Die Betroffenen leiden unter einem Niacinmangel (Vitamin B3), der sich u.a. durch eine Dermatitis und Diarrhö äussert."

"Pellagra tritt vor allem in Afrika, Südosteuropa und den USA bei Populationen auf, die sich vorwiegend von Mais ernähren. In Zentralamerika stellt Mais zwar ebenfalls ein Hauptnahrungsmittel dar, jedoch wird das Niacin durch die Behandlung der Maiskörner mit Kalkwasser verfügbar gemacht."

"Die Pellagra kann bei einer einseitigen Ernährung mit Mais- oder Hirseprodukten auftreten, die niacinarm sind oder Niacin in einer Form enthalten, die der Körper nicht verwerten kann. Als Voraussetzung für eine Pellagra muss zusätzlich eine mangelnde Eiweisszufuhr vorliegen, da der Körper in der Lage ist, Niacin aus der Aminosäure Tryptophan zu bilden."

"

Typische Symptome sind die "drei D’s":

• Dermatitis (Photodermatose mit charakteristischem Casal-Kragen)
• Diarrhoe
• Demenz

Zusätzlich können eine Glossitis ("Schwarzzungenkrankheit") und eine Polyneuropathie auftreten."

Website

Corn flour: 1,61

Website

Nr. 56 Maize (corn) groats and meal

DOI: 10.5194/hess-15-1577-2011

Narratives Review

Corn (Zea mays Linnaeus), also known as maize, is a member of the family Poaceae or Gramineae. It is indigenous to Mesoamerica and was domesticated in Mexico some 9,000 years ago, then it spread throughout the American continents [22]. Now, it is widely cultivated all over the World. The native corn includes 10,000 species, grouped in 600–700 different genera and this family includes wheat, oats, barley and rice [23]. All parts of corn are utilized, including the silks."

DOI: 10.3390/molecules17089697

Study: weak evidence

Habe das Buch nicht.

Book

"The term dry milling is often used to describe three distinctly different processes when discussing maize processes. The first process, stone grinding, is the oldest and is also known as whole kernel dry milling or full-fat dry milling. Whole kernel dry milling does not fractionate the maize kernel but rather seeks to grind the kernel to uniform particle size, usually flour or meal. The term ‘stone ground’ refers to the use of two stone grinding plates between which the maize is ground into a flour or meal. Other devices for particle size reduction can be used to produce meal or flour, including hammer mills, pin mills, and disk mills. The defining characteristics of this type of dry milling are that no separation of kernel components takes place and the resultant product is used for human nutrition. The products are usually referred to as ‘full-fat’ flour or ‘full-fat’ meal because the germ has been left unseparated from the other components. Full-fat products have a fuller flavor but a much shorter shelf life than degermed products due to the potential for oxidation of the germ oil, causing rancidity of the product."

"The third process referred to as maize dry milling is the process we are considering in this article. More accurately referred to as degerminated dry milling, this process attempts to remove germ and pericarp from the collection of grits, meal, and flour that are left. Degermination improves shelf life of the endosperm products by removing the germ oil in the maize kernel (
75%)."

DOI: 10.1016/B978-0-12-394437-5.00238-2

Book

Deskriptiver Überblicksartikel

"Different types of maize are grown throughout the world, with one important difference being color. Maize kernels can be different colors ranging from white to yellow to red to black. Most of the maize grown in the United States is yellow, whereas people in Africa, Central America, and the southern United States prefer white maize. Yellow maize is not popular in Africa for reasons associated with the perception of social status: apparently it is associated with food-aid programs and is perceived as being consumed only by poor people. Also, the feed industry consumes mostly yellow maize in the manufacture of animal feed.4"

"There is a classification of maize on the basis of the size and composition of the endosperm, resulting in an artificial definition by kernel type as follows: dent, flint, waxy, flour, sweet, pop, Indian, and pod corn. Another difference or classification criterion is the sweetness or amount of sugar. The amount of residual sugar depends on the variety of maize and when it is harvested from the field. Sweet maize stores poorly and must be eaten fresh, canned, or frozen before the kernels age, becoming small, tough, and starchy. Sweet varieties cannot be fortified.15, 16"

DOI: 10.1111/nyas.12396

Narratives Review

Table 4. Degerminated maize products defined by particle size and fat content.

"In the nixtamalization process, there are several stages. First, dried maize is soaked in a solution of water with lime, often with ashes mixed in. The grain is then cooked, steeped, drained, and rinsed multiple times. The grain is then ground to make a wet dough from which tortillas are formed or allowed to dry into flour. ... Nixtamalized maize has several benefits compared to unprocessed grains: they are more easily ground and have a higher nutritional value (increased bioavailability of niacin, improved protein quality, increased calcium) and reduced mycotoxins content.17"

"Worldwide, 60–70% of maize production is used domestically as livestock feed, and the remaining 30–40% is used for production of items for human consumption."

"More recently, the use of corn as a biofuel has generated great concern about rises in the market price of corn for consumption, the need to increase cultivable areas, as well as water quality and other ecological damages. Some predictive models project that large-scale corn ethanol production could lead to decreases in food exports, higher prices, and a greater global deforestation."

"Industrial dry milling includes particle size reduction of clean whole maize with or without screening separation, retaining all or some of the original maize germ and fiber.¹⁴ Because of the high-fat content, these whole or partially degerminated maize products are not particularly shelf stable. Degermination of maize involves mechanical separation and processing, resulting in dry shelf-stable products with a majority of both germ and fiber removed. Much of the particle size reduction and separation is accomplished with equipment similar to that employed in wheat flour milling, including hammer mills, stone mills, roller mills, screeners, sifters, specific gravity separators, and aspirators. Specialized equipment, such as degerminators and de-hullers or peelers, may be employed in maize processing."

"A second type of industrial dry maize processing is alkali processing or nixtamalization in which whole maize is cooked with an excess of water treated with calcium oxide.¹³ The maize kernel may be ground whole, fractionated, or have other corn components added. Unlike wheat flour milling, processing equipment for alkali-treated corn is specialized to handle the moisture, chemicals, and heat required for wet processing. Conventional dry bulk material handling and processing equipment is employed with raw maize and dry finished product. The resulting intermediate product may be dried for commercial sales of further processed consumer food product. In North America and Mexico, dry alkali-processed maize flour is known as masa flour, a name that is not used in Spanish-speaking countries of Central and South America or non-Spanish speaking countries of Africa. These products are referred herein as alkali processed. The alkali process improves flavor, starch gelatinization, and water uptake. The process partially removes some of the germ and most of the pericarp, but the amount varies. In some cases, pericarp may be added into the process for visual product enhancement. The heating in the process causes loss of thiamine, riboflavin, niacin, fat, and fiber. As might be expected the calcium content increases owing to the alkali processing."

DOI: 10.1111/nyas.12299

Study: weak evidence