摘要:

The irradiation of fresh, raw poultry and of further‐processed poultry products has been the subject of research, testing, and evaluation since the late 1940s, along with red meat and other food irradiation applications. An enormous bank of information on all aspects of poultry irradiation has been developed over this period, through what has been a truly global effort. This review takes an up‐to‐date look at key aspects beginning with a look at why one might consider poultry irradiation in the first place. Since the international poultry trade sector has participated in poultry irradiation R&D in various ways over the years, and, since industrial‐scale poultry irradiation is now taking place in a few countries and has recently been approved in the United States, it is worthy of serious consideration by poultry producers everywhere. The ultimatebusinessdecision to adopt the technology is a complex one best addressed by a case‐by‐case industrial feasibility study. The ultimatepersonaldecision to purchase and to serve irradiated poultry should, on the basis of unshakable facts, be an unhesitating “yes” (when available at “the right price” taking into account the added benefit/value accruing from the irradiation). There is a good reason to anticipate that this will be the case among the overwhelming majority of the consuming public, including in the US if and when the US poultry industry implements the May 2, 1990, approval of fresh and frozen raw poultry irradiation up to a 3‐kilogray maximum dose.

ISSN:8755-9129    

DOI:10.1080/87559129109540913

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:8755-9129    

DOI:10.1080/87559129109540914

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The most important chemical reactions during the process of soybean protein foods are the intermolecular reactions among the residues exposed on the surface of the protein molecules through the denaturation process. In native soybean protein molecules, most amino acid residues responsible for the reactions—such as cysteine (‐SH), cystine (S‐S), and hydrophobic amino acid residues—are buried in the inside region of the molecule, inaccessible to water. These residues become reactable with each other through the exposure from the inside by heat denaturation during processing. The unique textures of soybean protein foods, such as tofu, kori‐tofu, yuba, and texturized products produced by extruder, etc., are the results of both the intermolecular interchange reaction between the exposed ‐SH and S‐S groups and the intermolecular hydrophobic reaction among the exposed hydrophobic amino acid residues. The exposure of amino acid residues is also important for the hydrolysis of soybean proteins by enzymes, through which soy sauce is produced, because the cleavage of the peptide bonds is carried out after binding between the active sites of the enzymes and the enzyme‐specific amino acid residues exposed through denaturation. These facts indicate the importance of the three‐dimensional structures of soybean protein molecules in the technology of soybean protein foods. Recently great progress has been made in the manufacturing techniques of soybean protein foods, such as soy milk, tofu, abura‐age, textured protein products, and soy sauce. The quality of soy milk and tofu was very much improved by controlling the action of the biologically active substances such as lipoxygenases and β‐glucosidases which are contained in soybeans and responsible for the production of off‐flavor. A new abura‐age, whose texture does not deteriorate during frozen storage or drying, was developed by using soybean protein isolate and oil as materials. A new type of textured protein product was also developed: a deep‐fat‐fried nugget with unique texture and flavor. This product is textured through a twin‐type extruder. For soy sauce manufacturing new biotechnology has been applied on the pilot‐plant scale. This is a system of continuous fermentation through bioreactors with the immobilized whole cells of microorganisms, by which the fermentation term is shortened strikingly. New and important discoveries were made on the nutrition of soybean proteins. According to recent experiments using human beings, the amino acid score of soybean proteins is 100 for persons more than 2 years old, indicating that the nutritive value of soybean proteins is equal to animal proteins. Further, it was elucidated that soybean proteins have cholesterol‐lowering action. A discussion is presented on the future of the soybean protein foods.

ISSN:8755-9129    

DOI:10.1080/87559129109540915

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The complete amino acid sequence of plant storage protein molecules has been determined over the past decade by sequence analysis of full‐length cDNA and genomic clones for most cereal and legume seeds. At the same time, knowledge on the biosynthesis of the storage proteins has also been accumulated at the molecular level. According to the data on the gene structures of the plant storage proteins, the homology of their amino acid sequences, and the mechanisms of their accumulation into the protein bodies in the biosynthesis, the storage proteins which are classified as glutelins by a traditional sequential extraction method should be classified as either globulins or prolamins on the basis of the molecular structures. For instance, both orizenin, the rice main storage protein, and glutenin, the most important protein component of wheat proteins, have been classified as glutelins, but they should be classified as globulins and prolamins from the molecular base standpoint, respectively. The amino acid sequences of 7S and 11S globulins of legumes such as soybeans, peas, kidney beans, etc., showed considerable sequence homology and predicted secondary structural identity among 7S globulins or among 11S globulins. In addition, there was a high degree of re‐latedness on the secondary structures, even between the 7S and 11S globulins. The 11S‐type globulins exist widely, not only in legumes, but also in sesame, rape seed, rice, oat, pumpkin, etc. Furthermore, the amino acid sequences of these globulins showed quite a high homology each other. These facts indicate that the 11S globulins, which are distributed very widely among the different species, have all evolved from a common origin. The storage proteins of corn, wheat, rye, and barley are the typical prolamins, of which amino acid sequences are quite different from those of the globulin. The characteristic structural feature of the prolamin molecules is the presence of a repetitive peptide structure in their polypeptide chains. The functional properties of storage proteins and their mechanisms are described at the molecular level both from the gelation of soybean 7S and 11S globulins, and from the viscoelastic properties of the high molecular weight (HMW) subunits of wheat glutenin. In the gel formation of 7S globulins, no ‐SH/S‐S interchange reaction participates and therefore the gels are soft and transparent, whereas in the gel formation of 11S globulins, the interchange reaction participates, which makes the resultant gels firm and turbid. In addition, the subunit compositions of the 11S globulin molecules markedly effect the hardness, turbidity, and rates of gelation of the 11S gels. The viscoelastic properties of wheat HMW subunit are ascribed to the β‐spiral structures of the repetitive central domain, which are assembled into long linear polymers through covalent crosslinks via cysteine residues between the ‐NH2and ‐COOH termini. A discussion on the improvement of the plant storage proteins as food by genetic engineering techniques is presented.

ISSN:8755-9129    

DOI:10.1080/87559129109540916

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Manuals of Food Quality Control. 10. Training in Mycotoxins Analysis. FAO Food and Nutrition Paper 14/10. Food and Agriculture Organization of the United Nations, Via delle terme di Caracalla, 00100 Rome, Italy, 1990, 113 pp. US distributor: UNIPUB, 4611‐F Assembly Drive, Lanham, MD 20706–4391. $14.50 + postage and handling.

ISSN:8755-9129    

DOI:10.1080/87559129109540917

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:8755-9129    

DOI:10.1080/87559129109540912

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor