Strawberries for Ice Cream Manufacture

The increasing demand for food products flavored with true fruits and fruit juices is of special interest to the ice cream manufacturer. Many cold packed fruits are available on the market although in numerous cases fruits are sold as cold packed which are actually preserved by the addition of various preservatives such as sodium benzoate

The quality of butter made from Vacuum-pasteurized and Vat-pasteurized lots of the same creams

During the past few years a large amount of butter manufactured in the Middle West has been criticised for weedy flavors. This increase in weedy flavors unquestionably has resulted from a number of successive dry years. Some of the most common weed defects in this section are wild onion (Allium cernuum) , ragweed (Ambrosia artemisiifolia L.) and dog fennel (Anthemis cotula L.). The defects resulting from skunk cabbage (Symplocarpus foetidus (L.)), french weed (Thalaspi arvense L.) and peppergrass (Lepidium verginicum L.) (2) are apparently less common. Feed flavors are more important than weed flavors in this section. It has been recognized for some time that silage and alfalfa hay, when fed to dairy herds in fairly large quantities, cause definite milk flavors that are apparent in the butter. Changes in feeding procedures designed to lower fat production costs have, in many cases, increased the problems of the buttermaker. Sweet clover, rye pasture, wheat pasture, soybean hay and cane silage, flavor milk to such an extent that they affect the quality of the resulting butter

Observations on the counting of bacteria in ice cream by the plate method

The development of official or standard methods for various types of laboratory examinations represents a distinct advance from the standpoint of the usefulness of the results obtained. The standard methods for the bacteriological analysis of milk have made it possible to compare, on a satisfactory basis, the results secured in different laboratories and, undoubtedly, have been a factor in extending the use of bacterial counts for the control of milk supplies. The procedure at present required by Standard Methods of Milk Analysis1 for the macroscopic colony count on milk has been developed over a period of years. It is generally recognized that there are other media and incubation conditions which would give higher counts but none of these is at present standard because of the desire to employ a procedure which is easily carried out and comparatively inexpensive

The influence of the type of butter culture and its method of use on the flavor and keeping quality of salted butter

The search for methods of buttermaking that would yield a uniform product of good keeping quality led to the introduction of cream pasteurization and the ripening of the treated cream with selected cultures of bacteria. At about the time this procedure was developed, evidence began to accumulate which indicated that salted butter made from sweet cream deteriorated less on holding than salted butter made from ripened cream and, eventually, the influence of acid on certain types of chemical deterioration in butter was definitely established. The conflict between a high acidity in the cream and good keeping quality in the resulting butter has necessitated drastic changes in the methods of using butter culture in the manufacture of salted butter. Over the years, in an attempt to avoid certain types of deterioration in the butter, there has been a gradual lowering of the cream acidity at churning. Most butter plants in the United States now use a relatively low acidity in the cream. The general procedure is to hold the mixture of cream and butter culture at a low temperature in order to avoid significant increases in acidity

Diacetyl and other Alpha-Dicarbonyl compounds with special reference to the flavor of butter

Diacetyl is an important flavor contributor of butter and various other foods. Similarity in chemical structure suggests that a number of other a-diketones would be similar in certain properties, including odor, to diacetyl, the simplest member of the series. Diacetyl and various homologs were synthesized long ago their reactions studied and certain similar chemical behaviors noted. However, the descriptions of the odors originally given would hardly suggest that diacetyl is involved in the flavor of certain foods. The work of van Niel, Kluyver and Derx (81) showed the importance of diacetyl as a flavor contributor of butter. Epstein and Harris (22-25) patented the use of certain a-diketones as flavoring materials for various foods. Taufel and Thaler (74) incidentally mentioned that in practice acetylpropionyl was sometimes used as a substitute for diacetyl

Temperature dependent spatial oscillations in the correlations of the XXZ spin chain

We study the correlation $$ for the XXZ chain in the massless attractive (ferromagnetic) region at positive temperatures by means of a numerical study of the quantum transfer matrix. We find that there is a range of temperature where the behavior of the correlation for large separations is oscillatory with an incommensurate period which depends on temperature.Comment: 4 pages, REVTEX, 6 table

Dynamical correlation functions of the XXZ model at finite temperature

Combining a lattice path integral formulation for thermodynamics with the solution of the quantum inverse scattering problem for local spin operators, we derive a multiple integral representation for the time-dependent longitudinal correlation function of the spin-1/2 Heisenberg XXZ chain at finite temperature and in an external magnetic field. Our formula reproduces the previous results in the following three limits: the static, the zero-temperature and the XY limits.Comment: 22 pages, v4: typos corrected, published versio

Spectrum and transition rates of the XX chain analyzed via Bethe ansatz

As part of a study that investigates the dynamics of the s=1/2 XXZ model in the planar regime |Delta|<1, we discuss the singular nature of the Bethe ansatz equations for the case Delta=0 (XX model). We identify the general structure of the Bethe ansatz solutions for the entire XX spectrum, which include states with real and complex magnon momenta. We discuss the relation between the spinon or magnon quasiparticles (Bethe ansatz) and the lattice fermions (Jordan-Wigner representation). We present determinantal expressions for transition rates of spin fluctuation operators between Bethe wave functions and reduce them to product expressions. We apply the new formulas to two-spinon transition rates for chains with up to N=4096 sites.Comment: 11 pages, 4 figure

The great barrier reef: A source of CO2 to the atmosphere

Highlights • Seasonal variations in air-sea CO2 fluxes on the Great Barrier Reef reveal a strong CO2 release during the early-dry season. • The Great Barrier Reef is overall a net source of CO2. • CO2 fluxes are largely controlled by cross-shelf advection of oversaturated warm surface waters from the Coral Sea. Abstract The Great Barrier Reef (GBR) is the largest contiguous coral reef system in the world. Carbonate chemistry studies and flux quantification within the GBR have largely focused on reef calcification and dissolution, with relatively little work on shelf-scale CO2 dynamics. In this manuscript, we describe the shelf-scale seasonal variability in inorganic carbon and air-sea CO2 fluxes over the main seasons (wet summer, early dry and late dry seasons) in the GBR. Our large-scale dataset reveals that despite spatial-temporal variations, the GBR as a whole is a net source of CO2 to the atmosphere, with calculated air–sea fluxes varying between −6.19 and 12.17 mmol m−2 d−1 (average ± standard error: 1.44 ± 0.15 mmol m−2 d−1), with the strongest release of CO2 occurring during the wet season. The release of CO2 to the atmosphere is likely controlled by mixing of Coral Sea surface water, typically oversaturated in CO2, with the warm shelf waters of the GBR. This leads to oversaturation of the GBR system relative to the atmosphere and a consequent net CO2 release