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Food requirements

The presence of nucleic acids ia yeast is oae of the maia problems with their use ia human foods. Other animals metabolize uric acid to aHantoia, which is excreted ia the uriae. Purines iagested by humans and some other primates are metabolized to uric acid, which may precipitate out ia tissue to cause gout (37). The daily human diet should contain no more than about 2 g of nucleic acid, which limits yeast iatake to a maximum of 20 g. Thus, the use of higher concentrations of yeast proteia ia human food requires removal of the nucleic acids. Unfortunately, yields of proteia from extracts treated as described are low, and the cost of the proteia may more than double. [Pg.394]

Nahrungs-aufnahme, /. reception or absorption of food, -bedarf, m. food requirement, -brei, m. chyme, -dotter, m. (Biol.) food yoljc, deutoplasm, -fliissigkeit, /. nutritive liquid chyle, -kanal, m. alimentary canal, -milch, /. (Physiol.) chyle. [Pg.312]

Manufacture of liquid or solid foods requiring sanitary construction Laminar or Turbulent 4-10... [Pg.338]

Most packaged foods require a barrier against gases, flavors, or odors to maintain product quality and provide acceptable shelf life. Baked foods usually need moisture protection, while fresh meats and vegetables require low or controlled exposure to oxygen... [Pg.238]

Table I shows the chemical composition limits of various aluminum alloys presently used for packaging applications (3). In general, these alloys have good corrosion resistance with most foods. However, almost without exception, processed foods require inside enameled containers to maintain an acceptable shelf life (4, 5). Moreover, when flexible foil packages are used for thermally processed foods, the foil is laminated to plastic materials that protect it from direct contact with the food and also provide heat sealability as well as other physical characteristics (6,7). Table I shows the chemical composition limits of various aluminum alloys presently used for packaging applications (3). In general, these alloys have good corrosion resistance with most foods. However, almost without exception, processed foods require inside enameled containers to maintain an acceptable shelf life (4, 5). Moreover, when flexible foil packages are used for thermally processed foods, the foil is laminated to plastic materials that protect it from direct contact with the food and also provide heat sealability as well as other physical characteristics (6,7).
Dried or freeze dried samples can be extracted with water-immiscible solvents such as EtOAc or diethyl ether. For quantitative extraction, dried samples are preferably rehydrated at different times for example, 5 to 10 min for dried mangoes, 30 min for lyophihzed red peppers and pasta. Rehydration is followed by extraction with acetone or MeOH. Bixin and norbixin from a mix dry powder of annatto and com can quantitatively be extracted with MeOH followed by acetone. In order to improve pigment recovery, extruded foods require pre-digestion with enzymes to liberate the pigment from the matrix. ... [Pg.450]

The identification of synthetic colorants (pure or mixtures) in foods is usually carried out using spectrophotometry but the resolution of complex mixtures in food requires a previous separation of extract components by SPE and chromatographic techifiques. Dual wavelength, solid phase, and derivative spectrophotometric methods combined with chemometric approaches have been used. ... [Pg.539]

As the pig grows, it deposits progressively more fat relative to lean tissue. Thus food conversion efficiency decreases from 2.4 at 45-50 kg liveweight, to 2.76 at 68-73 kg, to 3.45 at 95-100 kg. Food conversion efficiency is the amount of food required per kg of liveweight gain. [Pg.66]

The structures of four of the synthetic carotenoids (beta-carotene, canthaxanthin, beta-apo-8 -carotenol, beta-apo-8 -carotenoic acid) are shown in Fig. 8.2. By virtue of their conjugated double bond structure, they are susceptible to oxidation but formulations with antioxidants were developed to minimize oxidation. Carotenoids are classified as oil soluble but most foods require water soluble colorants thus three approaches were used to provide water dispersible preparations. These included formulation of colloidal suspensions, emulsification of oily solutions, and dispersion in suitable colloids. The Hoffman-LaRoche firm pioneered the development of synthetic carotenoid colorants and they obviously chose candidates with better technological properties. For example, the red canthaxanthin is similar in color to lycopene but much more stable. Carotenoid colorants are appropriate for a wide variety of foods.10 Regulations differ in other countries but the only synthetic carotenoids allowed in foods in the US are beta-carotene, canthaxanthin, and beta-8-carotenol. [Pg.186]

When using the term flavor , a certain inherent understanding of the term is evident. However, its use in the technical discussion of food requires a more imprecise definition. A common technical definition of the word flavor is the sum total of the sensory responses of taste and aroma combined with the general tactile and temperature responses to substances placed in the mouth. Flavor can also mean any individual substance or combination of substances used for the principal purpose of eliciting the latter responses. This latter usage will be the way in which the term is used in this chapter. [Pg.207]

Contemporary risk assessment practices for pesticides in foods require far more data than simply the residue levels evaluated in government monitoring programs. Exposure to pesticides is determined by multiplying the residue levels on food by the amount of the food item consumed once determined, exposure is compared with standard toxicological criteria derived from animal toxicology studies to determine the acceptability of the exposure. [Pg.265]

Intraspecies variation in food requirement and dietary composition variation between individuals and over time in the proportion of food that is contaminated... [Pg.22]

The technological feasibility of a food irradiation treatment depends on how much irradiation the food withstands without adversely changing its qualities, i.e., how much useful effect can be achieved without significant change to the chemical composition, nutritional value, and sensory properties of the product. Generally, there is a minimum dose requirement. Whether every mass element of a food requires irradiation will depend... [Pg.787]

Regarding packaging materials for irradiated foods, most commonly used food packaging material are suitable for the purpose. However, irradiation of prepackaged food requires approval of its packaging material [132]. [Pg.805]

Recent approaches to the amino acid analysis of foods require maceration of the sample, hydrolysis of the proteins with HC1, and filtration. The resulting material may still include proteins (and fragmented peptides), carbohydrates, salts, urea, and lipids. The solution is then passed through a small column of cation exchanger (with a nominal cross-linking of at least 8%) in... [Pg.466]

United States regulations on nutrition labeling of foods require that cholesterol content be given and that it be analyzed by GC measurement as shown in the AOAC method, which uses a packed column (Lewis et al., 1996 AOAC, 1990). The reference value, which is a set of recommended nutrient intake levels of cholesterol, is defined as 300 mg. However, the Codex guideline does not request labeling of cholesterol. Cholesterol contents in some foods and foodstuffs determined by GC measurement are summarized in Table Dl.3.3. [Pg.464]

For GLC and HPLC analysis, the extraction of total lipids from food requires overnight separation of the organic layer. If the sample volume is small, however, centrifugation of the extract may shorten the sample preparation time. Cholesterol derivatization requires <2 hr depending on the number of samples. The peak of TMS ether and cholesterol benzoate derivatives will be eluted within 10 min after the injection of the sample. [Pg.464]

Furthermore, as an extract of a natural product is concentrated, the number of odorants detected increases indefinitely. Clearly, most of the odorants in a natural product are below their odor threshold, and it is only the most potent compounds that are involved in generating the flavor response. An odorant can be very potent at extremely low concentrations if it has an extremely low odor threshold, (unit go). In practice, early GC/O analysts attempted to concentrate the sample as far as possible to identify as many potential odorants as possible. Compositional studies combined with threshold studies were then used to sort out the important odorants from the ones that did not contribute to the flavor experience. Rothe s odor units (OU = concentration in sample/threshold in sample) were an early attempt to rank odorants by potency. The process of determining OU values for a food required a lot of chemical and psychophysical analysis. Dilution analysis was developed to produce an OU-like value directly from GC/O without the need to know the identity of the odorant. In fact, the real value of dilution analysis is that it can tell the analyst which compounds to identify. [Pg.1105]

The determination of the free phenolic acids in foods requires hydrolysis, because the phenolics are usually found in the conjugated form and rarely in the free state. When the separation... [Pg.787]

The assessment of mutagenic activity in cooked foods requires tedious extraction work in order to isolate and quantify the responsible chemicals at the nanogram level. Efforts have been made to develop a rapid and efficient method to obtain chromatograms free of interfering material. Coextracted matrix components influence analyte detection limits more than does absolute detector sensitivity (182). The sample workup therefore is the most critical part of the analysis (183). Solid-phase extraction with different coupled columns provides an improvement (176) over LLE and the use of large columns filled with XAD resin. The determination of PAHs and PANHs in food has been carried out by different chromatographic techniques, including LC with fluorescence (164,171,184) and/or UV detection (185,171) and GC with FID (168,186) or MS detection (187). [Pg.897]

Chekunova, V.I. and Naumov, A.G. (1982). Energy metabolism and food requirements of marbled notothenia (In Russian). Voprosy Ikhtiologii 22,294-302. [Pg.264]

Timokhina, A.F. (1974). On the food requirement of blue whiting in the Norwegian Sea and at Pockyolain Shoal (In Russian). Gydrobiologicheskii Zhumal 10,57-63. [Pg.317]

Vinberg, G.G. (1956). The Intensity of Metabolism and Food Requirements of Fish (In Russian). Belorussian University Press, Minsk, 253 pp. [Pg.319]


See other pages where Food requirements is mentioned: [Pg.149]    [Pg.438]    [Pg.511]    [Pg.138]    [Pg.184]    [Pg.162]    [Pg.28]    [Pg.324]    [Pg.526]    [Pg.36]    [Pg.297]    [Pg.7]    [Pg.284]    [Pg.501]    [Pg.13]    [Pg.303]    [Pg.54]    [Pg.1045]    [Pg.1119]    [Pg.1124]    [Pg.103]    [Pg.365]    [Pg.124]    [Pg.175]    [Pg.175]    [Pg.207]    [Pg.128]   
See also in sourсe #XX -- [ Pg.6 ]




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Food allergen labeling requirements

Food and Drug Administration requirements

Food processing, requirements

Food system, energy requirements

Inks, requiring food colorants

Insects food requirements

Physical requirements for food appearance assessment

Plant food requirements

Plant food units requirements

Regulatory Affairs Meeting the U.S. Food and Drug Administration (FDA) Requirements

Requirements and Occurrence in Foods

What Does the Food and Drug Administration Require

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