Rice byproducts

Other Names: Rice bran, rice polishings, rice pollards Nutritional Characteristics:

Rice by-products are the result of dehulling and cleaning of brown rice, necessary for the production of white rice as a human food. Rice byproducts are one of the most common cereal byproducts available to the feed industry, with world production estimated at around 45 m tonnes. The by-product of preparing white rice, yields a product called rice bran, which itself is composed of about 30% by weight of rice polishings and 70% true bran. In some regions, the two products are separated, being termed polishings and bran. Alternatively, the mixture is sometimes called rice bran, whereas in other areas the mixture may be called rice pollards. The polishings are very high in fat content and low in fiber while the true bran is low in fat and high in fiber. The proportions of polishings and true bran in a mixed product will therefore have a major effect on its nutritive value. In the following discussion, rice bran refers to the mixture of polishings and bran. The composition of any sample of mixed rice bran can be calculated based on levels of fat vs fiber.

Because of a high oil content (6 - 10%) rice bran is very susceptible to oxidative rancidity. Raw bran held at moderate temperatures for 10 - 12 weeks can be expected to contain 75 - 80% of its fat as free fatty acids, which are themselves more prone to rancidity. Rice bran should be stabilized with products such as ethoxyquin. Higher levels of ethoxyquin give greater protection against rancidity although economical levels appear to be around 250 ppm. Rice bran can also be stabilized by heat treatment. Extrusion at 130°C greatly reduces chances of rancidity, and of the development of free fatty acids.

When high levels of raw rice bran are used (□ 40%) there is often growth depression and reduction in feed efficiency, likely associated with the presence of trypsin inhibitor and high levels of phytic acid. The trypsin inhibitor, which seems to be a relatively low molecular weight structure, is destroyed by moist heat, although phytic acid is immune to this process. The phosphorus content of rice bran is assumed to be only 10%

available for very young birds. However, phosphorus availability may increase with age, and if this happens, it could create an imbalance of calcium:phosphorus. This latter effect is suggested as the reason for improved growth response in older birds fed rice bran when extra calcium is added to the diet. Phytase enzyme can be used to advantage in diets containing > 15% rice bran. Because of the potential for high fiber con tent, use of rice bran may be improved with addition of exogenous arabinoxylanase enzymes.

Potential Problems:

Rice bran should be stabilized with an antioxidant if storage at the mill is to be longer than a few weeks. Heating is advisable if young birds (< 3 weeks) are fed > 10% rice bran, to limit adverse effects of trypsin inhibitor.

Pregnancy Diet Plan

Pregnancy Diet Plan

The first trimester is very important for the mother and the baby. For most women it is common to find out about their pregnancy after they have missed their menstrual cycle. Since, not all women note their menstrual cycle and dates of intercourse, it may cause slight confusion about the exact date of conception. That is why most women find out that they are pregnant only after one month of pregnancy.

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