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The purpose of the paper is to study the effect of the gliadin and glutenin fractions of gluten on the cookie quality.

Ten different wheat varieties were analyzed for the flour physicochemical characteristics, gluten composition and rheological properties. The different flours were baked into cookies. The cookies were analyzed for spread ratio and texture. Relationships of various flour parameters, gluten composition and cookie characteristics were determined.

Gluten subfractions, damaged starch, protein, AWRC values were significantly correlated to the cookie spread and texture. Damaged starch (r=−0.638), protein (r=−0.508) and AWRC (r=−0.844) had a negative relationship with the cookie spread. The flours with higher SDS sedimentation value also produced cookies with lower spread ratio and harder texture. The study clearly demonstrated a positive correlation between Gli:Glu ratio (r=0.765) and spread ratio and a negative correlation (r=−0.528) with hardness of the cookies measured in terms of breaking force. Flours with lower dough development time and dough stability performed better as cookie flours.

The gliadins and Gli/Glu ratio had a significant effect on the cookie spread and texture and the prediction equation developed during the study could accurately predict the cookie spread from the Gli/Glu ratio and AWRC values.

Genetic engineering offers an opportunity to improve aspects of the agronomic performance, resistance to pests and pathogens and end use quality of crops by inserting specific genes. Discusses the basic principles and procedures of plant genetic engineering, including the use of particle bombardment for delivery of genes into regenerable tissues. Also discusses how this technology can be used to alter the level (up or down‐regulation) or pattern of expression of endogenous genes, or to insert novel activities or properties by inserting genes from other sources (other plants, animals or microbes). Finally, describes work in progress in our own laboratories on the improvement of the bread‐ making quality of wheat by manipulating the amount and composition of the HMW subunits of glutenin.

The biochemical basis for differences in wheat protein functionality A great deal of research has been carried out to try to determine, in chemical terms, why wheat proteins are so unique from a functional viewpoint. Although some progress has been made, a complete understanding of the molecular properties that are important to the functionality of these proteins is still distant. The reasons for this are that wheat proteins are extremely complex and they are difficult to study, using the more usual techniques of protein chemistry, because of their insolubility except under rather extreme conditions.

From what has been said in this journal regarding standards and associated regulations for jams and allied products, it appears that this is the only English‐speaking country where no standards and no regulations exist for this very important item of the food supply. We manufacture more jam than any other of these countries. We are the greatest consumers, per head of population, of jam. It is therefore a very serious disadvantage to the consumer that it should be left entirely to financially interested persons to formulate their own standards for their own advantage. It would be inexpedient in any case to allow this, but when such “standards” as those we have referred to have been adopted by a great combine, and the products made in conformity with those standards forced on the consumer, a case bad to begin with is made worse. The greater proportion of the jam and marmalade put on the market is either of poor quality or of very poor quality. The poor quality stuff may be labelled “Full Fruit Standard,” and the meaning that is to be attributed to these words is left to the purchaser to find out. We say that this legend is no recommendation, and in saying this we find our opinion to be supported by at least one important member of the combine. One of their labels is before us as we write. The words “This marmalade is guaranteed to conform to the agreed standard of the Food Manufacturers' Federation” is printed in such small type that it is by no means easy to read; it is printed at the very bottom of the label and in such a way that at first glance it appears to be merely an ornamental border. Now the object of making the marmalade is to sell it, and if in the opinion of the makers the words which we have quoted above would aid that sale they would have been conspicuously displayed and printed in large letters on the label. The label also says that the marmalade is made “from … oranges and sugar”; it does not say that it is made from oranges and sugar only. Now this label may be taken as a fair specimen of all the rest. It gives the purchaser no information about that which he is buying, and it is safe to say that not one person in ten thousand knows anything about the “standards” referred to. If the interests of the consumer were fairly balanced against the profits of the manufacturer, a label would read more or less as follows:—“This product conforms to the standard of the Food Manufacturers’ Federation.” “It consists of fresh (name) fruit or fruits and sugar only in the proportions — per cent. fruit and — per cent. sugar.” If there is nothing to fear there is nothing to conceal. Why then is such a label not used?

The March issue of the Journal of Chemical Technology contains the following article, with every word of which we cordially agree. It is gratifying to find that there is one—if only one—of our scientific Journals which has the courage and the patriotism to speak out and to do so in vigorous terms. The indictment of the flabby persons belonging to the Chemical Profession who by their ineptitude and inertia are condoning the bestial crimes of the modern Huns is well‐timed and thoroughly deserved.

The purpose of this paper is to evaluate the viscoelastic quality of commercial vital wheat glutens from different origins (A and B) through simple tests, and correlate these results with dough rheological parameters measured using more complex equipment (farinograph and extensograph) and with bread quality characteristics (specific volume and crumb firmness) obtained from wheat flour fortified with 7 g/100 g of vital gluten.

For the evaluation of vital gluten quality, two commercial vital wheat gluten named A and B were used. The simple tests performed with these samples were wet and dry gluten contents and index gluten, extensbility test and expansion test. The Pearson correlation was performed among data from dough rheological tests (farinograph and extensograph) and bread quality parameters (specific volume (SV) and crumb firmness) obtained from the fortification of wheat flour with 7 g/100 g of VGA or VGB (previous work, data not shown).

The simple tests showed differences in the viscoelastic properties of vital gluten A and B; vital gluten A presented higher elasticity and lower extensibility than vital gluten B, and the gluten ball of sample A presented higher SV. By correlation analysis, it was verified that the simple tests studied may be useful to assess the baking performance of commercial vital gluten when this product is added to wheat flour for its fortification. Furthermore, the results indicate the need for more information on vital wheat gluten proteins for its commercialisation and use.

This work is very important, not just for the scientific community, but also for the bakery industry, that requires more information about vital wheat gluten before its use in bread making. As there are great differences in the protein quality of commercial vital wheat glutens and their functionality, the study was developed to solve this problem.

In the second part of this report the action of nitrogen peroxide on flour is discussed at some length in an account of a series of researches that have been carried out by DR. MONIER‐WILLIAMS. His conclusions may be briefly stated as follows. The maximum bleaching effect is obtained when each kilogram of flour is treated with from 30 to 100 cubic centimetres of nitrogen peroxide. The bleaching effect becomes more pronounced after keeping for several days. The amount of nitrous acid or nitrites that are present in bleached flour corresponds to about 30 per cent. of the total nitrogen absorbed, the proportion of nitrites present remaining nearly constant after the lapse of several days in the more slightly bleached samples. After the lapse of a short time it is still possible to extract about 60 per cent. of the nitrogen absorbed by the flour by means of cold water, but after several days the nitrogen that can be extracted by this means decreases. This may perhaps be attributed to the “absorption” of nitrous acid by the glutenin and gliadin. In highly bleached flour (300 cubic centimetres of nitrogen peroxide per kilogram of flour) a considerable increase in the amounts of soluble proteins and soluble carbohydrates takes place. In highly bleached flour, after some time, about 6 or 7 per cent. of the nitrogen introduced as nitrogen by the nitrogen peroxide is absorbed by the oil, which acquires the characteristics of an oxidised oil. No evidence is forthcoming as to the formation of diazo compounds nor the production of free nitrogen. Bleaching was found to exercise an inhibitory action on the salivary digestion of flour.

Reviews the factors affecting bread‐making quality in UK wheat: condition; milling quality (endosperm quality, high flour yield and good flour colour); water absorption; baking quality; protein quantity and quality; α‐amylase activity.

Gluten is the nitrogenous part of the flour of wheat which remains behind as a sticky, cohesive substance when the starch is removed by kneading a flour dough in a current of water.

Concentrates on the type and importance of flour proteins by discussing their structure and evaluating their function in bread making. Intends to introduce the reader to some of the complex interactions which take place during the preparation of bread by discussing some of the chemical and physical changes which are involved in bread making. Examines the composition of wheat flour and discusses an explanation of its suitability as a bread‐making flour. Emphasizes the importance of protein type in flour and how these proteins can be identified in flour. Explains the development of the gluten network, essential for the production of bread.