bluuebunny/crossref_metadata_2025 huggingface dataset:
FACTORS INVOLVED IN THE ISOLATION OF CLOSTRIDIUM PERFRIHGEHS1
Authors: Smith Louis DS.
Published: December 2016

Quantitative isolation of Clostridium perfringens requires that dilutions be made anaerobically; that a relatively complete medium be used; that incubation be under strictly anaerobic conditions or that the medium contain an active reducing agent. Roll tubes, pour plates, or surface-inoculated plates may be used if other conditions are suitable.

Selective agents inhibitory for other bacteria but only slightly for C. perfringens include sulfite, neomycin, polymyxin, sulfadiazine, kanamycin, and cycloserine. Several selective media utilizing such agents have been devised but none inhibits all other bacteria without some inhibition of C. perfringens, SFP medium ( Shahidi, Ferguson, perfringens medium) is the least inhibitory both for other bacteria and for C. perfringens. TSN medium (tryptone, sulfite, neomycin) is most inhibitory for other bacteria, but is also somewhat inhibitory for C. perfringens. SPS medium (sulfite, polymyxin, sulfadiazine) is intermediate in these properties.

The number of living C. perfringens cells in food or other material can also be estimated by using the MPN technique and incubating at 45 C. If the C. perfringens in the specimen have been killed by freezing or cold storage, the numbers originally present may be estimated by determining the amount of phospholipase C that is present.
BACTERIOLOGICAL EXAMINATION OF RAW BREADED FROZEN SHRIMP1
Authors: Nickerson J. T. R. , Pollak G. A.
Published: December 2016

Total plate counts and tests for enterococci, total coliforms, and Escherichia coli were made on a number of frozen raw, breaded shrimp samples. These shrimp samples were the products of different packers picked up at retail in different cities of the United States. Results of plate counts (average of two plates) varied for individual samples from 24,000 to 60,000,000 per gram. While no enterococci were detected in some samples, counts of this type as high as 55,000 per gram were obtained in others. Coliforms in individual samples varied between none detected and an MPN of 8,850 per gram.
VARIATIONS OF SOMATIC CELLS AND NEUTROPHILS IN MILK THROUGHOUT LACTATION1
Authors: Duttschaever C. L. , Ashton G. C.
Published: December 2016

Total and differential cell counts were obtained for alternate weekly morning and evening milk from 11 Holstein cows in six different lactations. Milk from quarters suspected of mastitis were examined for presence of pathogens. Weekly cell counts for each cow showed large variations throughout lactation. The neutrophil count closely paralleled the total cell count. The average neutrophil percentage varied from 65 to 96%. No relationship was observed between cell count or type and length of lactation, age of cow, and milk yield. In addition to mastitis, unspecified stresses seemed to cause irregular sudden increases in somatic cells. Except during severe stresses, total cell counts were about 200,000 per milliliter, of which 65 to 90% were neutrophils.
BACTERIAL COUNTS OF RAW MILK AND FLAVOR OF THE MILK AFTER PASTEURIZATION AND STORAGE
Authors: Patel G. B. , Blankenagel G.
Published: December 2016

A total of 216 raw milk samples with a variety of Standard Plate Counts and psychrotrophic bacteria counts were laboratory-pasteurized, stored at 7 C, and then evaluated for flavor after 1 and 2 weeks. Results showed that milk with counts of >1,000,000/ml before heating frequently developed objectionable flavors after pasteurization and subsequent storage. The most common defect was a bitter flavor which appeared within 2 weeks after pasteurization in nearly all samples which as raw milk had counts exceeding 10,000,000/ml. This off-flavor developed in spite of small numbers of organisms in the pasteurized product and in the absence of post-pasteurization contamination.
STAPHYLOCOCCUS AUREUS AND STAPHYLOCOCCAL FOOD INTOXICATIONS. A REVIEW
Authors: Minor T. E. , Marth E. H.
Published: December 2016

Staphylococcal intoxications involving foods, other than dairy products, have been associated predominantly with meats and bakery items. Outbreaks involving Genoa sausage, corned beef, barbecued chicken, baked ham, fish, pastries, pie fillings, and other foods are reviewed. Because meats have caused food-poisoning outbreaks, commercial samples have been tested for incidence of staphylococcal contamination. Several surveys have revealed that approximately 40% of the samples tested contained coagulase-positive staphylococci. These and other surveys, including studies of some frozen foods, are discussed. Finally, results of research concerning the behavior of staphylococci in several foods are discussed. Investigations on raw, cooked, canned, cured, and smoked meats, and meat pies have been reported in the literature. Studies on pastry and pie fillings have also been conducted and are summarized in this review.
THE VALUE OF ADDING IRON AND NONFAT DRY MILK SOLIDS TO A MILK DIET IN THE RECOVERY OF ANEMIC RATS
Authors: Demott B. J.
Published: December 2016

Weanling rats were fed only homogenized vitamin D milk for 3 weeks at which time the body weights were about 105 g and the hematocrit values were 20.4 for males and 22.8 for females. They were then fed milk plus 10 ppm elemental iron in the form of ferric pyrophosphate, milk plus 10% added nonfat dry milk solids, or milk plus 10 ppm iron plus 10% nonfat dry milk solids. After 3 weeks on the milk-plus-iron diets, the hematocrit values for males and females were about 30 and 40, respectively. Weekly body weights and hematocrit values showed the two iron-supplemented diets to be nutritionally similar (P>.05) when rats were fed ad libitum. Rats fed milk plus added nonfat dry milk solids were significantly lower (P<.05) in body weight after 10 weeks of age and significantly lower (P<.05) in hematocrit value after 8 weeks as compared to rats fed either of the iron-supplemented diets.
QUALITY CONTROL IN THE CALIFORNIA WINE INDUSTRY1
Authors: Amerine Maynard A.
Published: December 2016

The post-Pasteurian trends in quality control in the wine industry are reviewed. The post-Repeal state and Federal wine standards and their effects are discussed. The contributions of various text books are noted. Specific problems, river disposal of stillage, pond disposal of liquid winery wastes, and tartrate decomposition are mentioned. The activities of the Wine Institute in this field are reviewed, particularly its Sanitation Guide for Wineries and its recommendations. The problem of antiseptics, fungicides, and pesticides as they relate to the wine industry are mentioned.
CHANGES IN THE MICROFLORA OF WILD RICE DURING CURING BY FERMENTATION1
Authors: Goel M. C. , Marth E. H. , Stuiber D. A. , Lund D. B. , Lindsay R. C.
Published: December 2016

Freshly harvested wild rice piled 18 inches deep was allowed to ferment for 34 days at ambient temperature or at 10 C (50 F). Some rice at ambient temperature and all rice at 10 C was moistened daily (1 gal water/100 lb. rice). Samples were taken at intervals during the fermentation and tested for numbers and kinds of microorganisms. Each time samples were taken some rice of each lot was parched (dried) at approximately 79 C (175 F) for 1 hr and then was tested microbiologically. The initial total count (gram-negative rods predominated) of freshly harvested wild rice ranged from 1.7–16.0 × 108 and increased during fermentation regardless of storage conditions. Molds (1.8–5.0 × 105/g initially) also increased in number with less growth evident at the lower storage temperature. Growth of psychrotrophs (mainly Pseudomonas spp.) was greatest when wild rice was fermented at 10 C. Some growth of coliforms was evident but results were erratic. Escherichia coli, Enterobacter areagenes, and intermediate forms were isolated. Growth of fecal streptococci during fermentation was minimal; Streptococcus faecalis was recovered from some samples and Streptococcus faecium from the same or other samples. Predominant molds were Mucor spp., aflatoxinogenic and nontoxlgenic Aspergillus spp., Penicillium spp., and Rhizopus sp.

Bacillus spp. predominated in parched wild rice regardless of how long the rice was allowed to ferment before it was heated. Coliforms, pseudomonads, fecal streptococci, and molds also were recovered but only from a few samples. Microbial numbers in parched rice generally were <1.0% of those in the unheated product.
EFFECTS OF DEHYDRATION THROUGH THE INTERMEDIATE MOISTURE RANGE ON WATER ACTIVITY, MICROBIAL GROWTH, AND TEXTURE OF SELECTED FOODS
Authors: Chordash R. A. , Potter N. N.
Published: December 2016

Various food systems were inoculated with Pseudomonas aeruginosa and Staphylococcus aureus and vacuum-dried to different moisture contents in the intermediate moisture range. Water activity (aw) values were determined instrumentally with a hygrometer indicator equipped with appropriate hygrosensors. Sorption isotherms and bacterial growth curves at the various water activities were plotted and correlated with food texture, Growth of P. aeruginosa was inhibited at aw test values below 0.98, 0.98, and 0.96 in custard, pea, and beef products, respectively, and growth of S. aureus did not occur below aw test values of 0.94 and 0.96 in custard and ham products, respectively. These results generally agree with earlier work done on model systems. With none of the foods studied could microbiologically stable intermediate moisture products of acceptable texture be produced by drying alone.
LOCATING LEAKS IN EGG PASTEURIZERS
Authors: Kaufman Vern F.
Published: December 2016

The U. S. Department of Agriculture tests for leaks in egg pasteurizers indicate only whether a leak is or is not present. Three tests for locating leaks in plate heat exchangers, after leaks have been indicated, have been evaluated from laboratory and plant trials. For an entire regeneration or cooling section a test using diazo paper and ammonia gas is feasible. Individual plates removed from the press can be tested by using diazo paper and ammonium hydroxide. A penetrant dye and developer test will confirm the exact location of a hole after its possible location has been reduced to a small area.
ENVIRONMENTAL ASPECTS OF HOUSING
Authors: Bell Irving
Published: December 2016

Housing is a part of man's total environment and hence it is to some extent responsible for the status of his health and well-being. The residential environment may affect man's physical health by influencing the transmission of communicable diseases, by not fulfilling his physiological needs, or by causing injury. Although approximately 60% of the U. S. population is currently covered by an adopted local or state housing code, it has been estimated that 16 to 20 million of the some 70 million dwelling units in the United States are so far below standard they should be replaced.

To cope with environmental problems related to housing and to protect the health of the nation's citizens, health agencies must accept the role of either stimulating or carrying out the four kinds of governmental action set forth below: (a) adoption of minimum health standards in housing; (b) conduct a program to achieve and maintain such standards; (c) conduct periodic evaluation of the standards to ensure their current adequacy; and (d) monitor the standards enforcement effort to guarantee that public health values are provided.
AGRICULTURAL SANITATION OF LIVESTOCK MANURES FOR CONTROL OF FLIES, ODORS, AND DUSTS1
Authors: Loomis Edmond C.
Published: December 2016

Industrial agriculture and urban-rural growth are mainly responsible for the FOD (Flies, Odors, Dusts) nuisance problems associated with livestock industries in many states. Manure from animal confinement type operations is a major source of these nuisances. Drylot dairies, beef feedlots, and raised wire-cage poultry ranches are the main industries which affect the co-existence of agricultural and suburban living. An Agricultural Sanitation Program by the University of California consists of these principal activities: research, demonstrations, and education. Physical, mechanical, biological and chemical methods are combined into an integrated control program with major emphasis on manure management including collection, disposal, and use. Cooperative research programs also are made with interdisciplinary personnel representing federal, state, and local agencies in line with state and local codes and ordinances governing control of FOD problems.
INJURY AND REPAIR OF SEVERAL SALMONELLA SEROTYPES AFTER FREEZING AND THAWING IN MILK SOLIDS1
Authors: Janssen D. W. , Busta F. F.
Published: December 2016

Freezing and thawing of Salmonella anatum cells induced increased sensitivity to selective agents in the plating medium. Selective plating media containing the bile salt sodium desoxycholate were most inhibitory. Injury was demonstrated in 11 Salmonella serotypes. The percent injury ranged from 20% (Salmonella heidelberg) to about 60% (Salmonella pullorum, Salmonella anatum, Salmonella infantis, and Salmonella cubana). The percent death ranged from 10% (Salmonella meleagridis and Salmonella infantis) to 27% (Salmonella pullorum and Salmonella oranienburg). The data indicated that 2,4-dinitrophenol prevented repair of injury in all serotypes that exhibited at least 25% injury. This suggested the importance of energy synthesis in the repair process.
A COMPARISON OF THE BABCOCK, MOJONNIER, AND MILKO-TESTER MARK III METHODS IN THE ANALYSIS OF MILKFAT IN CREAM1
Authors: Packard Vernal S. , Ginn Roy E. , Rosenau John R.
Published: December 2016

The Babcock, Mojonnier, and Milko-Tester Mark III methods of milkfat analyses were compared on creams ranging in milkfat from 6.6 to 50.0%. Variances (s2) of the three methods on 243, 246, and 336 observations, respectively, were 0.062, 0.048, and 0.017. Variability tended to increase with an increase in milkfat content of the creams. This was true for all three methods. Regression formulae for estimating Babcock and Mojonnier values from Milko-Tester values were, respectively, ŷ = −0.94795 + 1.06699 (X), and ŷ = −0.60222 + 1.04850 (X). Correlation coefficients for the Milko-Tester Mark III with the Babcock and Mojonnier methods were 0.9987 and 0.9983, respectively. These relationships were noted with the Milko-Tester unit calibrated on whole milk, and indicate the feasibility of Milko-Tester use on cream samples whether calibrated at lower milkfat levels and calculated from regression formulae, or calibrated at the approximate range of milkfat test expected and read directly.
DISTRIBUTION OF VIBRIO PARAHAEMOLYTICUS IN THE NATURAL ENVIRONMENT1
Authors: Liston J. , Baross J.
Published: December 2016

Vibrio parahaemolyticus has been isolated widely from marine environments but appears to be most abundant in in-shore and estuarine areas where ambient temperatures rise seasonally to levels permitting growth of the organism. Japanese and U. S. studies of coastal areas have shown a direct relationship between temperature and abundance of V. parahaemolyticus and this correlates with the seasonal incidence of V. parahaemolyticus food poisoning in Japan. The organism has been isolated from water, sediment, plankton, fish, and shellfish. In North America it seems to be most abundant in molluscan shellfish and in waters of high organic content. Counts of 10–200/ml of water, 1–7/g of sediment and up to 105/g of oyster tissue have been reported for North American inshore areas. Limited information on market seafood samples indicates very low incidence of V. parahaemolyticus on fin fish in Europe and North America and high incidence in Japan during summer months. Limited data on market samples of frozen and fresh shellfish in U.S.A. suggest sporadically high incidence on shrimp, crabmeat, oysters, and clams.
FLAVOR CHARACTERISTICS OF EGG YOLK AS AFFECTED BY DIFFERENT AMOUNTS OF SODIUM SULFATE IN THE LAYING HEN DIET1
Authors: McCready S. T. , Damron B. L.
Published: December 2016

Eggs from Single Comb White Leghom hens (DeKalb) fed a standard laying hen diet supplemented with 0, 0.4, 0.8 or 1.2% sodium sulfate were stored at 13 C for six weeks and hard-cooked at weekly intervals for flavor evaluation of the yolk. Triangular taste tests indicated that egg yolk from hens fed a diet containing 1.2% sodium sulfate were different in flavor when compared to control eggs stored the same length of time. Panelists indicated that hard-cooked yolks produced by hens on the 1.2% sodium sulfate diet were drier, of coarser texture, and generally less flavorful than were yolks produced by hens on the control diet. There were no significant flavor differences noted between yolk from fresh control eggs and those from a 1.2% sodium sulfate supplemented diet. Total sulfur analyses of whole eggs indicated no significant differences in the sulfur content of whole eggs from hens fed the control or sodium sulfate supplemented diets.
A CASE STUDY: SYNERESIS OF COLD-PACK CHEESE FOOD RELATED TO GROWTH OF LACTIC ACID BACTERIA
Authors: Duttschaever C. L. , Irvine D. M.
Published: December 2016

Commercial Cold-Pack Cheese Food which exhibited marked syneresis in consumer packages had a pH of 4.60 to 4.80. Bi-weekly microbial examination of commercial Cold-Pack Cheese Food stored at 5, 10, 15, and 20 C indicated a marked growth of lactobacilli and streptococci at all temperatures above 5 C and a slight decease in staphylococci at all temperatures. It is assumed that the lactose added in the form of skim-milk or whey powders provided the carbohydrate nutrient source for these organisms so that the pH was reduced from 5.05 to 4.60, The minimum hydration of casein occurs at pH 4.60 and this lowered pH caused syneresis in the packages. Cooling the Cold-Pack Cheese Food quickly to 5 C and keeping it at or below this temperature eliminated the problem.
SOLIDS–LIQUID SEPARATION: AN IMPORTANT STEP IN THE RECYCLING OF DAIRY COW WASTES1,2
Authors: Dale A. C.
Published: December 2016

Use of a solids-liquid separator in the manegement of dairy cattle wastes may (a) reduce labor requirements, (b) make mechanical handling more feasible, (c) improve automation, (d) produce solids with economic value, and (e) produce a liquid that may be handled by ordinary equipment and treated to produce potable water and fertilizer. In solids-liquid separation of dairy cattle wastes, macro-colloidal (> 5μ) and larger solid particles are partially removed from the liquid portion by screens, sieves, and compressors. The two products produced, are (a) wet solids and (b) a dilute liquid. The solids contain about 45 to 80% water depending on the systems used and are stable in nature. The solids have little or no odor and may be dried and used for bedding, refeeding, or mulch, thus having economic value. The liquid is dark brown in color and contains about 85–90% of the 5-day BOD and only about 1–3% suspended and dissolved solids. It may be handled by ordinary equipment and does not require special liquid pumps and high-powered tractors for mixing, pumping, and conveying. The liquid may be irrigated directly onto crops and soils or it may be treated to make potable water and a more concentrated fertilizer.
VIRUSES IN FOODS1
Authors: Potter Norman N.
Published: December 2016

Many virus-food interrelationships are not yet well understood and hence a meaningful assessment of the health hazard caused by several foodborne viruses cannot be made at the present time. Interest in this area is growing, however, and investigations involving methods for quantitative recovery of viruses are being facilitated by increased commercial availability of animal and human cell cultures and tissue culture media. This paper reviews pertinent literature, discusses some of the problems inherent in studies of viruses in foods, and cites several areas deserving of further research.
FATE OF BACILLUS CEREUS IN CULTURED AND DIRECT ACIDIFIED SKIMMILK AND CHEDDAR CHEESE1
Authors: Mikolajcik E. M. , Kearney J. W. , Kristoffersen T.
Published: December 2016

Germination, growth, sporulation, and. survival of Bacillus cereus 7 was determined in cultured (Streptococcus lactis C10) and direct acidified (lactic acid) skimmilks. For cultured systems, B. cereus increased initially at approximately the same rate in milks with or without streptococci. However, as the acidity of the milk increased, vegetative B. cereus cells failed to survive but spore counts remained unchanged. B. cereus organisms did not influence acid production or multiplication of the lactic streptococci. In direct acidified skimmilk, spore germination and outgrowth and vegetative cell multiplication decreased as the pH of the system was lowered from 6.5 to 5.0. In skimmilk at pH 5.0, vegetative cells failed to multiply and spore germination ceased. In Cheddar cheese manufacture, B. cereus multiplied rapidly during the period from the end of cooking to milling of the curd. B. cereus survived in the spore state in Cheddar cheese during 52 weeks curing.
RED MEAT AND POULTRY INSPECTION: MICROBIOLOGY OF EQUIPMENT AND PROCESSING1
Authors: Elliott R. Paul
Published: December 2016

The Federal Meat and Poultry Inspection Program (MPIP) requires that equipment be properly designed and cleaned frequently. Cooked ready-to-eat foods must be physically separated from raw foods and held below 40 F or above 120 F except for short periods. Microbiological plant inspections form the basis for microbiological criteria which MPIP is now considering for several commodities. Final product objective surveillance has recently begun on these. Sampling and analysis of final product as a means of protecting the consumer against an infrequent hazard is not feasible. Even hundreds of determinations give unacceptably low protection when the hazard is severe. Control at the source—i.e., at the processing plant—is the practical way to protect consumers with the limited resources available in laboratory programs. The MPIP microbiological sanitation program is a combination of investigation, surveillance, and correction. For example, the 1971 investigations of staphylococcal food poisonings from fermented sausages developed rapidly from final product tests, to investigations of cause, and to bacteriological inspections and corrections.
DETERGENTS, PHOSPHATES, AND ENVIRONMENTAL CONTROL1
Authors: Barrett Robert B. , Brunelle Thomas E. , Podas William M.
Published: December 2016

Eutrophication and its relationship to the detergent industry is analyzed. The role of phosphorus in accelerated or “cultural” eutrophication is discussed and the different uses of phosphorus by all industry are presented. The detergent industry is broken into its different sectors of marketing, and the distinction is made between household laundry detergent products and that of the specialty detergent and sanitizer products. Application of specialty detergents and sanitizers is discussed and their role in maintaining public health and safety standards is related. Remedial steps being taken to reduce “cultural” eutrophication are discussed and a request is stated that, if legislative or judicial actions are deemed necessary in the problem of “cultural” eutrophication, reasonable thought be given to the effect those actions may have in the critical area of product application of the specialty detergents and sanitizers.
MAGNETIC SEPARATION OF STEEL CANS: A KEY TO SOLID WASTE MANAGEMENT1
Authors: Cherneff J. Robert
Published: December 2016

A growing number of communities are finding that municipal magnetic separation of steel cans is an ecological, economic, and technological solution to part of their solid waste problem. Steel's unique magnetic property permits the large-scale efficient reclamation of steel cans from collected municipal garbage.

Magnetic separation enables municipalities to extend the life of scarce landfill sites, produces revenues from the sale of scrap cans, lowers the cost of waste disposal, and helps conserve a valuable resource through recycling. It also leads to salvaging vastly greater numbers of used cans than do the volunteer collection programs.

Successful recycling programs require that economically viable markets be maintained for reclaimed materials. America's steel industry is actively developing uses for reclaimed steel cans. Steel producers have agreed to accept all reclaimed steel cans for remelting into new steel products. Also, the copper mining industry uses salvaged cans to produce copper from low grade ore. Detinners and ferroalloy plants offer additional markets for salvaged steel cans.
PASTEURIZATION OF GRADE “A” MILK AND MILK PRODUCTS BY STEAM INJECTION
Authors: Dickerson R. W. , Stroup W. H. , Thompson H. E. , Read R. B.
Published: December 2016

Steam injection systems are in common use in some parts of the United States. They have not been recognized, however, as a satisfactory method for pasteurizing milk and milk products because of possible poor mixing of steam and product, vapor formation in the holding tube, and inadequate public health controls. Recent research has solved these problems and steam injectors may be used to pasteurize milk products when the steam and product flows are isolated from the pressure fluctuations in the injection chamber, when no vapor is formed in the holding tube, and when non-condensable gases are eliminated from the steam supply. The injection chamber is isolated by installing supplementary orifices of a proper size at the injector ports to maintain a product pressure drop of 10 psi across the injector. Vapor formation is prevented by maintaining a holding tube pressure 10 psi above the boiling pressure of the liquid product. Non-condensable gases are eliminated from the steam supply by installing an approved deaerator in the boiler system.
FOOD PROTECTION DURING DISTRIBUTION1
Authors: Schenck Paul
Published: December 2016

In-plant inspectors in federally-inspected meat plants are satisfactorily inspecting trucks that distribute meat and meat products In other food plants, inspections are more random and could be improved. Some truckers claim bias and lack of consistency in the acceptable degree of cleanliness. Refrigerated trucks on the road today are better than they have ever been before, and there are more of them. However, not all trucks meet the minimum standards of temperature protection and cleanliness. Food sanitarians can do a better job of checking trucks for their ability to safely transport perishable cargo, which would result in less claims damage and loss to both carrier and shipper.
A TRUNCATED SEQUENTIAL PROCEDURE FOR DETERMINING SOMATIC CELL COUNT OF MILK BY THE STRIP METHOD1
Authors: Ginn Roy E. , Packard V. S. , Cook R. D.
Published: December 2016

The Direct Microscopic Somatic Cell Count (DMSCC) “strip” method requires the counting of four strips on two separate milk films. An evaluation of five technicians and 231 milk samples, using a truncated sequential procedure for making cell counts, indicated the potential for significantly reducing the number of strips counted, with little loss in validity of results. For conditions observed in this market, counting of cells could be terminated after the first strip in 85% of the instances with a somatic cell standard set at 1.5 million or higher. Four strips would have to be counted in only 4% of the samples. With the standard set at 1 million or higher, these market conditions would permit one-strip counting 68% of the time, and would necessitate four-strip counting in only 20% of the samples.
FLAVOR DEVELOPMENT AND MICROBIOLOGY OF SWISS CHEESE–A REVIEW
Authors: Langsrud T. , Reinbold G. W.
Published: December 2016

This review, appearing in four parts, deals with relationships between flavor development and the microbiology of Swiss cheese. Body and texture characteristics of Swiss cheese also will be discussed, however, to a lesser degree and, wherever possible, in association with the flavor of Swiss cheese.

The first section, presented here, discusses use of raw milk and how the bacterial content of raw milk influences Swiss cheese quality. Thereafter, other milk treatments used in the cheese industry are discussed. They include clarification, heat-treatment, homogenization, and H2O2-catalase treatment of cheese milk. Changes in microbial flora and subsequent effects on Swiss cheese quality are included. Production of Swiss cheese with desirable body, flavor, and texture characteristics depends on use of low bacterial count, properly clarified milk. Mild [68 C (154.4 F) to 72 C (161.6 F) for 15 to 18 sec] heat treatment is recommended. Homogenization of cheese milk is not used and the H2O2-catalase treatment is not necessary.
FLAVOR DEVELOPMENT AND MICROBIOLOGY OF SWISS CHEESE-A REVIEW
Authors: Langsrud T. , Reinbold G. W.
Published: December 2016

The fourth and last paper of this series deals mainly with bacteriological defects in Swiss cheese. These include: lack of eye formation, crystal formation, split defect, early and late fermentation, bitterness, and other flavor and color defects. Ways to counteract development of these defects are discussed.
INHIBITION OF BACTERIA BY SOME VOLATILE AND NON-VOLATILE COMPOUNDS ASSOCIATED WITH MILK
Authors: Kulshrestha D. C. , Marth E. H.
Published: December 2016

APT broth inoculated with Streptococcus lactis was dispensed into epoxy-lined aerosol cans. Twenty-five milk-associated volatile or non-volatile compounds were added individually to cans to give final concentrations of 1, 10, 100, and 1000 ppm of each compound. The compounds used were formic, acetic, butyric, hexanoic, octanoic, and decanoic acid; formaldehyde; acetaldehyde; propionaldehyde; glyoxal; acetone; 2-butanone; diacetyl; propyl- and hexylamine; furfurol; methanol; methylsulfide; methylsulfone; methanethiol; ethanethiol; acetonitrile; chloroform; ether; and ethylenedichloride. Bacteria were enumerated at intervals during incubation at 30 C.

Fatty acids at 1000 ppm always significantly inhibited S. lactis. Decanoic acid was more active than other fatty acids at higher concentrations, whereas formic acid caused more inhibition of S. lactis when the acids were tested at a lower concentration (10 ppm). Formaldehyde was most inhibitory of the aldehydes tested. The lowest concentration of aldehydes was only marginally inhibitory. Diacetyl was more inhibitory than acetone or 2-butanone. Acetonitrile (100 ppm), chloroform (10 ppm), ether (10 ppm), and ethylenedichloride (10 ppm) always inhibited S. lactis. Lower concentrations of methylsulfone caused minimal growth stimulation early during the incubation, but later this changed to inhibition. Ethanethiol generally was more detrimental than methanethiol, and methylsulfide was less active against S. lactis than methanethiol. Amines were more inhibitory than alcohols.
INHIBITION OF BACTERIA BY SOME VOLATILE AND NON-VOLATILE COMPOUNDS ASSOCIATED WITH MILK
Authors: Kulshrestha D. C. , Marth E. H.
Published: December 2016

APT broth inoculated with Streptococcus thermophilus was dispensed into epoxy-lined aerosol cans. Twenty five volatile or non-volatile compounds likely to be present in milk were added individually to cans to attain concentrations in broth of 1, 10, 100, and 1000 ppm of each compound. Compounds used included formic, acetic, butyric, hexanoic, octanoic, and decanoic acid; formaldehyde; acetaldehyde; propionaldehyde; glyoxal; acetone; 2-butanone; diacetyl; propyl- and hexylamine; furfurol; methanol; methylsulfide; methylsulfone; methanethiol; ethanethiol; acetonitrile; chloroform; ether; and ethylenedichloride. Bacteria were enumerated at intervals during incubation at 37 C.

Of the six fatty acids tested, decanoic acid was most and hexanoic acid was least inhibitory to S. thermophilus. At 1000 ppm all fatty acids tested always significantly inhibited S. thermophilus. Formaldehyde was more inhibitory to the bacterium than were acetaldehyde, propionaldehyde, or glyoxal. Of the ketones tested, diacetyl was most effective against S. thermophilus. Acetonitrile, chloroform, and ether at 10 ppm or more were always inhibitory but significantly so only early during the incubation. At concentrations of 10 and 100 ppm ethylenedichloride and methylsulfone were significantly inhibitory late in the 14-h incubation. Methanethiol was generally more active than ethanethiol, but ethanethiol was more inhibitory than methylsulfide. Amines were always inhibitory and were more active than alcohols.
EXAMINATION OF OFFICIAL MEASUREMENT TOLERANCES FOR ONTARIO'S FARM MILK TANKS
Authors: Bullock D. H. , Biggs D. A. , Arnott D. R.
Published: December 2016

A random sample of 72 farm milk tanks was check-calibrated to determine whether official tolerances for estimates of milk weights were realistic. The overall calibration error for 859 calibration check values was + 3.12 1b. Sixty-nine percent of all values exceeded the official tolerances and this was reduced to 23% when the calibration check values for each tank were reduced by an amount equal to the mean calibration check error for the tank. Under these circumstances the official tolerances were approximately equal to one standard deviation of errors. When the tolerances were doubled (approximately two standard deviations), the percentage of the calibration check values which were excessive was reduced to 4.9%. It was concluded that the official tolerances were too small and should be doubled in size, giving a tolerance range of 6 to 16 1b. (0.5 to 0.18%) for a range of tank capacity from 1200 to 9000 1b.
SIGNIFICANCE OF BACTERIAL SPORES IN MILK1,2
Authors: Martin James H.
Published: December 2016

Sporeforming bacteria are present in practically all raw milk, but usually in small numbers if the milk is produced under modern sanitary conditions. There appears to be no relationship between total bacteria and spore counts, nor between total bacteria and the incidence of any given species of sporeforming organism. Bacillus species account for about 95% of the total sporeforming bacteria in milk, with Clostridium species comprising the remainder. In the United States, approximately 43% of the Bacillus organisms are B. licheniformis and 37% are B. cereus. Reports from some other countries indicate a predominance of B. cereus, or essentially a reversal in the prevalance of these two species. Spores of both these organisms survive low temperature pasteurization, some persisting through even the lower temperatures in the ultra-high range, and recent reports indicate that some sporeformers are psychrotrophic. B. cereus has been implicated in outbreaks of food-borne illness, but this is still controversial. Should B. cereus be proven capable of growing in the psychrotrophic range, and also responsible for food-borne illness, then the significance of spores in milk would take on added importance.
THE PROCESS CHEESE INDUSTRY IN THE UNITED STATES: A REVIEW1
Authors: Price Walter V. , Bush Merlin G.
Published: December 2016

Research and development (R & D) in corporate laboratories of cheese processors and in other research facilities in the United States have contributed knowledge of analytical technology, microbiology, defects and their corrections, manufacturing techniques, equipment, emulsifiers, and the use of other ingredients. Methods of wrapping and protecting the product during distribution were improved. Cheese foods and spreads with higher moisture, lower fat, and altered consistency were developed. The technology of producing slices of processed cheese has been revolutionary. Packages of slices are replacing the original, and highly successful, 5-lb. loaf. Mechanically formed, individually wrapped, and sealed slices are produced at fantastic speeds. Trends of industry indicate greater production per plant, more low-fat, high protein cheese products, and use of vegetable fats and proteins. Trends of R & D indicate improvements in emulsifiers, packaging, keeping quality, new products, and more mechanization and automation for greater efficiency and improved protection of this valuable food and its related products. The industry provides opportunities for trained food scientists, engineers, marketing specialists, and business administrators.
MICROBIOLOGY OF EGGS1
Authors: Baker Robert C.
Published: December 2016

It is generally agreed that milk and eggs are nature's most perfect foods. Milk is extremely perishable while eggs in the shell are not. The reason that eggs are not as perishable as most foods is that they possess protective devices including the cuticle, shell, shell membranes, lysozyme, conalbumin, avidin, pH of the albumen, etc. Having these protective devices is nature's way of allowing reproduction of birds. Chicken eggs, for example, take 21 days to hatch under ideal conditions for growth of microorganisms. Without the protection, reproduction could not take place. Once eggs are broken out of the shell and mixed, they are as perishable as milk. Pathogenic bacteria of concern to humans found in eggs (particularly liquid eggs) are Salmonella, Staphylococcus aureus, and Clostridium perfringens. These pathogens are not common in shell eggs but can be found in liquid eggs primarily because of reinfection by humans.
FLAVOR AND SHELF LIFE OF FLUID MILK1,2
Authors: Barnard Sidney E.
Published: December 2016

Today's consumer determines the acceptance of milk by flavor and shelf life. Rancid, oxidized, and strong feed tastes of raw milk need to be eliminated. To prevent rancid and psychrotrophic flavor development, milk should be processed within 24 h of collection. Hot water sterilization of processing and filling equipment is essential. Product temperatures below 40 F at the filler extend shelf life. Proper handling during delivery and in stores is necessary to maintain good taste and keeping quality. Temperatures below 40 F, minimal fluorescent light and daylight exposure, and proper rotation are the key factors. Containers vary in their ability to protect the flavor and change in milk composition. Holding quality programs of 14 days at 45 F should be adopted by industry. Ten-day coding or open dating should be practiced by all processors. Regulatory agencies need to permit tests which will indicate shelf life. More emphasis must be placed on factors which determine consumer acceptability. These are flavor and shelf life.
COMPARISON OF SALMONELLA POLYVALENT H ANTISERA, DIRECT FLUORESCENT ANTIBODY, AND CULTURE PROCEDURES IN DETECTING SALMONELLAE FROM EXPERIMENTALLY CONTAMINATED GROUND BEEF UNDER FROZEN STORAGE
Authors: Ladiges W. C. , Foster J. F. , Ganz W. M.
Published: December 2016

A direct fluorescent antibody (FA) test and a polyvalent H agglutination (poly H) test with separate gram-negative (GN) and tetrathionate (TT) broth enrichments were compared with culture methodology in detecting salmonellae from experimentally contaminated ground beef. The FA test had the most false-position reactions (28%, but concurrent culture results reduced these to 7%) and the lowest number of false-negative reactions (4%). The poly H test was more efficient when TT broth was used for selective enrichment. On the basis of fewer false-negative reactions and the greater number of false-positive reactions that were culturally confirmed to be salmonellae, the FA test would appear to be a more efficient screening test in detecting salmonellae from artificially contaminated ground beef held at frozen temperatures.
INHIBITION OF CLOSTRIDIUM PERFRINGENS BY STREPTOCOCCUS FAECALIS IN A MEDIUM CONTAINING CURING SALTS1
Authors: Tabatabai L. B. , Walker H. W.
Published: December 2016

Inhibition of two strains of Clostridium perfringens by Streptococcus faecalis in Cooked Meat Medium containing curing salts was investigated. Inhibitory effects were evaluated by growth-curve studies and by measurement of inhibition zones on agar. Both strains of C. perfringens were inhibited by S. faecalis in a medium containing glucose, although to different degrees. Addition of nitrite to the medium containing glucose increased the inhibitory effect of S. faecalis towards C. perfringens. Production of lactic acid by S. faecalis appears to play an important role in this inhibition of C. perfringens.
PRODUCTION OF AFLATOXIN IN CONCENTRATED AND DILUTED GRAPEFRUIT JUICE1
Authors: Alderman G. G. , Marth E. H.
Published: December 2016

Commercial concentrated and diluted (1:1, 1:2, 1:3; juice: water) steamed grapefruit juice was inoculated with known aflatoxigenic aspergilli and sampled after 10 and 14 days of incubation at 28 C. When Aspergillus flavus grew in juice, most aflatoxin B1 (0.211 μg/ml appeared in concentrated juice and least (0.013 μg/ml) in single strength juice. Juices diluted 1:1 and 1:2 yielded 0.078 and 0.020 μg B1/ml, respectively. Results were more striking when Aspergillus parasiticus grew in samples of juice. After 10 days, amounts of aflatoxin B1 in concentrated juice and in concentrated juice diluted 1:1, 1:2, and 1:3 were 7.5, 1.59, 0.69, and 0.56 μg/ml, respectively. Aflatoxins B2, G1, and G2 were also produced and greatest amounts also developed in concentrated juice. Amounts of these toxins decreased markedly when the percentage of soluble solids in the juices decreased. Fourteen instead of 10 days of incubation resulted in increases in the amount of each toxin in concentrated juice and in concentrated juice diluted 1:1. Although the greatest amount of aflatoxin occurred in concentrated juice, appearance of visible growth and onset of sporulation by the molds was slower in this than in diluted juices. The pH of the concentrated juice did not change appreciably after 10 and 14 days of incubation, but the pH of diluted juices rose progressively from the initial value as the percent soluble solids content in the juice decreased.
TEMPERATURE AND MICROBIAL FLORA OF REFRIGERATED GROUND BEEF GRAVY SUBJECTED TO HOLDING AND HEATING AS MIGHT OCCUR IN A SCHOOL FOODSERVICE OPERATION1
Authors: Tuomi S. , Matthews M. E. , Marth E. H.
Published: December 2016

The practices of handling precooked chilled gravy in school kitchens were simulated to determine if they could contribute to outbreaks of foodborne illness. Time-temperature measurements and bacteriological tests were made at intervals during chilling, holding, and heating of gravy. Sixty-six pounds of cooked ground beef gravy were packed hot (158 F, 70 C) in bags, cooled in chilled water for 1 h, and refrigerated for 16 h. The gravy was held for 5 h at 82 F (28 C) and at 42 F (5.5 C) and then it was heated in a compartment steamer for 35 min. After 1 h cooling in chilled water, the mean temperature of gravy was 82 F (28 C) and after 16 h of refrigerated storage, the temperature was 45.5 F (7.5 C). The mean temperature of chilled gravy held at 82 F (28 C) remained about 50 F (10 C) for 4 h and reached 64 F (18 C) at the end of the 5-h holding period. The mean temperature of gravy held under refrigeration for 5 h decreased 2 F, from 45.5 F (7.5 C) to 43.5 F (6.5 C). After 35 min of heating in a compartment steamer, the highest temperature was 136 F (58 C) for gravy initially at 65 F (18.5 C) and 128 F (53.5 C) for gravy initially at 47 F (8.5 C). Bacteriological tests indicated that the greatest increase in the number of total aerobic bacteria in gravy occurred during cooling rather than holding. Although some samples yielded coagulase-positive staphylococci, the numbers changed little during holding or heating. Clostridium perfringens was not found in any samples of the gravy.
A Rapid Method for the Aseptic Collection of Tissue
Authors: HONE J. D. , OCKERMAN H. W. , CAHILL V. R. , BORTON R. J. , PROCTOR G. O.
Published: December 2016

The existing methods of collecting muscle tissue samples, with a low microbial level, have many disadvantages which make them impractical for many research facilities. A procedure is described for obtaining 100 g samples of tissue containing very low microbial levels. The procedure consists of using a sterile coring device to remove samples deep within the longissimus dorsi muscle. The deeper tissue contains little, if any, bacterial counts since air contamination has not occurred. Of the 48 pork samples collected, 34% were found to be sterile(< 1 organism/g) and 64% had a level of ≤ 5 microorganisms per gram. Of the 23 beef samples collected, 22% were sterile (< 1 organism/g) and 74% had a contamination of ≤5 microorganisms per gram. With this procedure, a researcher with modest facilities can examine changes that occur in muscle tissue caused by specific microorganisms, enzymes and other treatments.
Microbiology of Processed Spices
Authors: POWERS EDMUND M. , LAWYER ROGER , MASUOKA YOSHITO
Published: December 2016

The microbiology of spices procured by the Army, Navy, Marines and Air Force was determined. The incidence of Clostridium perfringens in the spices analyzed was 15%. The organism was found in 4 out of 7 types of spice and in 53% of the oregano samples. No other bacteria of public health significance were found. The microflora of spices from 10 different brands varied widely.
High Solids Cabbage for Sauerkraut Production: Its Effects upon Brine Reduction and Yield of Product1
Authors: STAMER J. R. , DICKSON M. H.
Published: December 2016

Experimental cabbage hybrids, especially selected for increased dry matter content, were examined for their abilities to increase the yields of finished product (sauerkraut) and concomitantly decrease the volumes of extraneous brine. The new hybrids, containing 20% more dry matter than the commercial control (Roundup), reduced the amount of final brine 57% or 388 lbs per ton of shredded cabbage. When fermented and packaged under commercial processing conditions, Roundup produced 1928 lbs, whereas the new varieties provided 2728 lbs of sauerkraut per ton of shredded cabbage. High-solids cabbage containing greater amounts of dry matter increased the product yield 41% or 800 lbs per ton of shredded cabbage.
Farm Tank Temperature Recording: Its Effect on Quality and Marketability of Fluid Milk
Authors: HANSBERRY C. JOSEPH
Published: December 2016

The only positive method to assure both producer and processor that farm cooling tank temperatures within legal limits have been achieved and maintained during the holding period is with the use of a recording thermometer. The same instrument recrords washing time/temperatures, another critical aspect of maintaining product quality and observing safety limitations. Several summaries of random testing by state inspectors of farm cooling tank temperatures with portable recorders indicate a wide variance in compliance with regulations and underline the urgency for tighter control of stored milk temperatures on the farm.
Organochlorine Insecticides and Industrial Pollutants in the Milk Supply of the Southern Region of Ontario, Canada
Authors: FRANK R. , SMITH E. H. , BRAUN H. E. , HOLDRINET M. , McWADE J. W.
Published: December 2016

A province-wide survey conducted between 1967 and 1969 revealed that milk produced in the Southern region had the highest residues of organochlorine insecticides in Ontario. It was in this region where 90% of the organochlorine insecticides purchased in the province were applied. In 1969–70 restrictions were placed on DDT and the cyclodiene insecticides. Disappearance of these organochlorine insecticides from milk were studied in surveys conducted in 1970–71 and 1973. The mean ∑DDT levels declined from 0.20 ppm in 1967 to 0.05 ppm in 1973, whereas the mean dieldrin residues declined from 0.044 ppm to 0.015 ppm in the same period. These data include counties where there had been only small reductions in the use of DDT and where milk residues remained unchanged until further restrictions were effected in 1971. Residues of lindane and heptachlor epoxide were virtually absent from milk fat. Chlordane, endosulfan, methoxychlor and endrin were absent from all samples in spite of increasing quantities being used of the first two insecticides. Residues of polychlorinated biphenyls appeared slightly higher in the 1973 survey than in the 1970–71 survey. Hexachlorobenzene was present at very low levels in the 1973 survey.