A review of the recently reported moisture diffusivity experimental data in food materials is presented in this work Values are classified and analysed statistically to reveal the influences of temperature and moisture content Empirical models relating moisture diffusivity with the above variables, along with relevant graphs for various materials, are included Other factors affecting moisture diffusivity prediction are also discussed

Moisture Diffusivity Data Compilation in Foodstuffs

Revue bibliographique sur les transformations physicochimiques provoquees par la cuisson-extrusion sur l'amidon, les lipides, les proteines, les elements mineraux, les fibres, les vitamines, les contaminants et les facteurs antinutritionnels presents dans les aliments

Chemical and nutritional changes in foods during extrusion

http://ucce.ucdavis.edu/files/datastore/608-151.pdf

Environmental impact of novel thermal and non-thermal technologies in food processing

Radio frequency (RF) heating is a promising technology for food applications because of the associated rapid and uniform heat distribution, large penetration depth and lower energy consumption Radio frequency heating has been successfully applied for drying, baking and thawing of frozen meat and in meat processing However, its use in continuous pasteurization and sterilization of foods is rather limited During RF heating, heat is generated within the product due to molecular friction resulting from oscillating molecules and ions caused by the applied alternating electric field RF heating is influenced principally by the dielectric properties of the product when other conditions are kept constant This review deals with the current status of RF heating applications in food processing, as well as product and system specific factors that influence the RF heating It is evident that frequency level, temperature and properties of food, such as viscosity, water content and chemical composition affect the dielectric properties and thus the RF heating of foods Therefore, these parameters should be taken into account when designing a radio frequency heating system for foods

Radio frequency heating of foods: principles, applications and related properties--a review.

Oats (Avena sativa L.) have received considerable attention for their high content of dietary fibres, phytochemicals and nutritional value. It is believed that consumption of oats possesses various health benefits such as hypocholesterolaemic and anticancerous properties. Oats have also recently been considered suitable in the diet of celiac patients. Owing to their high nutritional value, oat-based food products like breads, biscuits, cookies, probiotic drinks, breakfast cereals, flakes and infant food are gaining increasing consideration. Research and development on oat and its products may be helpful in combating various diseases known to mankind. This paper provides an overview of the nutritional and health benefits provided by oats as whole grains and its value added products. It is designed to provide an insight on the processing of oats and its effect on their functional properties. The manuscript also reviews various uses of oats and its fractions for clinical and industrial purposes and in development of value added food products.

Nutritional advantages of oats and opportunities for its processing as value added foods - a review.

SUMMARY

Radio-frequency heating at 60 and 2450 MHz in conveyorized equipment was compared with conventional hot water treatment for pasteurization of small cured hams packed in Cryovac casings inside moulds For lean 2-lb hams, treatment time to reach the desired central temperature could be reduced to 1/3 by heating in a condenser field tunnel operating at 60 MHz, with substantial reduction of juice losses and a tendency to improve sensory quality compared with that obtained with hot water processing Treatment time could be further reduced by roughly the same extent by processing at 2450 MHz, but product thickness had to be reduced to secure sufficient heat penetration Temperature gradients end juice losses were comparable to those in hot water treatment At 2450 MHz in particular, but also at 60 MHz, bacterial surface counts were considerably higher than in the controls, suggesting the need for higher final surface temperature or supplementary heat treatment, which will lower the differences in processing time and juice loss between methods

Radio‐frequency pasteurization of cured hams

SUMMARY—

The following variables were determined at equilibrium between fish muscle and brine, all as functions of the salt concentration in the brine: salt concentration in the muscle, based on the volume of the muscle; salt concentration in the tissue water of the muscle; distribution coefficient of salt between muscle volume and brine; distribution coefficient of salt between muscle tissue water and brine. Secondary variables which further described the salting equilibria were also found as functions of salt concentration in the brine as follows, all based on unit weight of non-salt solids in the salted muscle: weight of salt (S/NSS), weight of water (W/NSS), and volume (V/NSS).



The salt concentration based on the muscle volume was found to increase continually with increasing brine concentration, as did the salt concentration in the tissue water and the salt content expressed as S/NSS. The distribution coefficient based on the muscle volume and the water and volume contents (W/NSS) and (V/NSS) were found to increase at first, pass through a maximum, and then decrease, all with increasing brine concentration. Within the limits of experimental error, the salt concentration in the tissue water was found to equal the salt concentration in the brine, so that the distribution coefficient calculated on this basis was always equal to unity and was independent of the salt concentration in the brine.



The volume per unit weight of non-salt solids (V/NSS) was found to be a direct linear function of the water content per weight of non-salt solids (W/NSS) at all temperatures studied. Little difference was found between the equilibrium salting variables when salting was carried out at 5 and at 25°C; on the other hand, possibly due to “cooking” or heat denaturation of the muscle with consequent loss of water at that temperature, all variables were considerably lower when salting was carried out at 37°C. The “mean molar activity coefficient” of sodium chloride in fish muscle was determined as a function of salt concentration in the muscle. It was found to be always greater, and to vary more sharply with salt concentration, than the corresponding activity coefficient of salt in aqueous solution.

Studies on Salting and Drying Fish. I. Equilibrium Considerations in Salting

Whole amaranth (Amaranthus cruentus) seed flour, its air-classified fractions and extruded blends of these with wheat and oats were studied with the purpose of evaluating their potential as components in the development in infant formulas. Proximal chemical analyses, mineral content, fatty acid composition of lipid fractions, amino acid analyses and Protein Efficiency Ratio (PER) and Net Protein Retention (NPR) values were obtained for all raw materials, as well as for 50:50 and 60:40 blends of these with oats and wheat. The 50:50 and 60:40 blends of whole amaranth, as well as of the protein-rich air-classified fraction, were found to be highly suitable for utilization in infant formulas.

Evaluation of Whole Amaranth (Amaranthus cruentus) Flour, Its Air-Classified Fractions, and Blends of These with Wheat and Oats as Possible Components for Infant Formulas

A simple and inexpensive method for enriching tortillas with soy proteins was studied. The method consisted of application of the traditional process for making corn tortillas to whole raw corn-soybean mixtures: lime cooking of a mixture, allowing the cooked mixture to stand overnight in the cooking liquor, washing the mixture with tap water, grinding the cooked mixture into a dough, and making tortillas from the dough. This method of enrichment was found to give tortillas with significantly higher protein content and protein quality than normal un-enriched tortillas. PER and NPU values of tortillas containing 8% and 16% soya were found to be comparable to those obtained with tortillas enriched with soy flour or with amino acids lysine and tryptophane. The presence of soybeans in tortillas so enriched was found to be not significantly detectable by a trained panel, at least up to a soya level of 16%. Toxic factors present in raw soybeans were not detected in enriched tortillas by the urease method, having been apparently inactivated by the tortilla-making process. Enrichment by this method is cheaper than enrichment with soy flour or with amino acids. The method permits uniform introduction of soya proteins within the tortillas, and changes neither food recipes nor eating habits.

Enrichment of tortillas with soy proteins by lime cooking of whole raw corn-soybean mixtures

SUMMARY– Drying of salted fish was studied in the falling rate period. It was found that this period consisted of two distinct phases, each of which was characterized by a Fickian diffusion coefficient. The coefficient for the first phase was, in all cases, greater than that for the second phase. The effect, on both diffusion coefficients, of the following variables was studied: degree of salting, drying temperature, and degree of hydration of -the muscle (varied by addition of acid, base and sodium trypolyphosphate to the muscle). The first diffusion coefficient was found to increase, pass through a maximum, and then decrease with degree of salting. The second coefficient was found to decrease with degree of salting within the range for which it was determined.

The first diffusion coefficient was found to be directly correlated with the degree of hydration of the muscle; a plot of the coefficient versus water content of the muscle (expressed as pounds of water per pound of bone-dry solids) yielded a straight line, the regression equation of which was found to be D = 0.16W + 0.09, where D is the diffusion coefficient in cm2/sec × 105 and W is the water content. Variations in the diffusion coefficient due to degree of salting and due to addition of acid, base, and phosphate could be explained by the hydration-dependence of the coefficient. The temperature variation of both coefficients was found not to be great.

F. R. Del Valle

Papers

Radio‐frequency pasteurization of cured hams

Studies on Salting and Drying Fish. I. Equilibrium Considerations in Salting

Evaluation of Whole Amaranth (Amaranthus cruentus) Flour, Its Air-Classified Fractions, and Blends of These with Wheat and Oats as Possible Components for Infant Formulas

Enrichment of tortillas with soy proteins by lime cooking of whole raw corn-soybean mixtures

Salting and Drying Fish. 3. Diffusion of Water