ALBERT

Notes: Between pH 2 and pH 10.5 the titration curve of washed native cod myofibrils can he accounted for solely on the basis of the probable dissociation constants of the carboxyl, histidyl, lysyl, and tyrosyl groups of the constituent proteins. On heat coagulation of washed cod myofibrils, a slight shift in the titration curve toward more alkaline pH's occurs, particularly between pH 4.5 and 7.0, but no evidence was obtained for experimentally significant changes in the numbers of titratable acid or basic groups. The titration curves of cod myofibrils prepared from fish stored at −14° for periods from 1 week up to 2 yr are very similar, and no evidence was obtained for loss of titratable acid or basic groups during frozen storage. The changes that occur in the titration curve of beef myofibrils on heat coagulation are similar to those occurring in the titration curve of cod myofibrils.

Notes: The activity of succinic dehydrogenase of post-rigor bovine tissue was determined at various temperatures and pH values. The oxygen uptake thus measured yielded typical curves. In the first 15 hr the uniform gas uptake can be accounted for by oxygenation of myoglobin, solution of oxygen and nitrogen, and enzymatic oxygen uptake. After 15 hr the oxygen uptake is due to enzymatic reaction. The enzymatic uptake of oxygen is about 0.7 μL/hr/g of wet tissue. The evolution of carbon dioxide was about 1.1 μL/hr/g of wet tissue. Tissue sample taken from deep in the musculature, however, showed a larger carbon dioxide evolution in the first 4 hr of exposure (before equilbrium is established) to au air atmosphere.

Notes: Application of the 2,4-dinitrophenylhydrazine method of Roe and co-workers to plant extracts, wherein ascorbic acid was present largely or completely in the form of DHA and DKA, resulted in abnormal data, in the sense that the value of AA + DHA + DKA was significantly lower than that of DHA + DKA. Such a discrepancy, though not to the same degree, was observed also when the analyses were carried out on solutions of DHA. The loss is believed to take place during H2S treatment, there being a correlation between the extent of loss and the duration of H2S treatment, in the majority of the experiments.

Notes: The carotenoids of ripe tomatoes were found to contain about 6% xanthophylls; the composition of the latter was about 15% monols, 49% diols, 4% monoepoxide diols, 22% diepoxide diols, and 11% polyols. The diol and polyol xanthophylls were much like those of green leaves, with lutein the major pigment, somewhat smaller amounts of violaxanthin and neoxanthin, and much smaller amounts of zeaxanthin, lutein 5,6-epoxide, and several others.The monol fraction contained lycoxanthin and “monol 487” (which may be 3-hydroxy-delta-carotene), together with substances tentatively identified as polycis isomers of lycoxanthin, rubixanthin, and “monol 487.”

Notes: Seasonal changes in concentrations of pectic substances of the peel and pulp were followed by determining the total- and water-soluble pectic substances as an-hydrogalacturonic acid during growth and development under normal conditions. With the rapid development of fruit growth in the early part of the season, a tremendous initial increase occurred in the total- and water-soluble pectic materials followed‘by a gradual decrease through the remainder of the season. The percentage methylation of the pectic substances of Valencia orange peel rises rapidly to approximately an 80 per cent level and remains relatively constant during the rest of the season.

Notes: This study has attempted to define the relationship of proteolysis to flavor during storage of irradiated raw beef. The data presented show that a decrease in consumer-type taste-panel preference during unrefrigerated storage of irradiated (4.5 megarad) raw ground beef correlates to some extent with the action of endocellular tissue proteolytic enzymes (cathepsins). The effective control of proteolytic activity using refrigerated storage is demonstrated. In the experiment cited, raw beef round steaks irradiated at a pasteurizing dose of 0.5 megarad were stable both microbiologically and enzymically, and the preference rating did not decline during six months at 3°C. The limited control of proteolysis during unrefrigerated storage using high-pH beef is shown. The use of high-pH beef for a limited extension of unrefrigerated storage life without significant decrease in preference rating is suggested. A need for further studies is indicated.

Notes: Effects of gamma irradiation on the chemical properties of actin and actomyosin during aging of meats have been studied. Meats were irradiated with 4 × 106 rad of cobalt-60 gamma rays at 40° F in three steps, i.e., immediately after slaughter, at maximum rigor, and at “rigor off.” Actin and two kinds of actomyosin (AMS and AML, previously reported by authors) were isolated from irradiated and control meats. The contents of sulfhydryl groups and amino acids, viscosity, the activity of ATPase and ATP sensitivity of actin and actomyosin were determined. From the results, actin is thought to be only slightly sensitive to irradiation as compared with actomyosin, and the latter, especially AML (a long-time extracted actomyosin) is considered to be very sensitive. In this case, it is inferred that the depolymerization must have taken place in actomyosin molecule by irradiation on meats. The effects of the time of irradiation on the chemical properties of actomyosin in meats seem to be more remarkable at rigor off than at the other two steps.

Notes: The relative importance of the hydroxyl group positions of quercetin and the metal-complexing sites of the molecule to antioxidant capacity in lard was investigated. The antioxidant action of quercetin seems to be a combination of reaction with free radicals and metal-ion complexing; with the former being the more important. Selective methylation of the hydroxyl groups of the quercetin molecule generally decreased the antioxidant activity. Ultraviolet absorption spectra of quercetin and copper-quercetin complexes suggest that quercetin will complex two moles of copper ion by intramolecular complexing and a third by intermolecular complexing. Copper-quercetin complexes retain some antioxidant ability although it is much less than that of uncomplexed quercetin.

Notes: The carbohydrates of the citrus peel were divided according to their solubility in 80% ethanol. The alcohol-soluble solids were composed of about 80% total sugars. Free xylose was found in trace amounts. Glucose, fructose, and sucrose were the main sugars present. Sucrose content of the peel was in general lower than the total reducing sugars. The alcohol-insoluble solids were separated into “pectic substance,”“hemicellulose,” and “cellulose” fractions by extracting with different solvents. The “pectic substance” fraction upon hydrolysis yielded arabinose, galactose, and galacturonic acid. “Hemicellulose” fraction contained xylose, arabinose, galactose, glucose, and some uronic acids in its hydrolysate. In the “cellulose” fraction, glucose was dominant with some xylose and arabinose being also present. Traces of galactose and some uronic acids and in some cases mannose were found. On the average only between 53 and 70 per cent of the alcohol-insoluble solids were recovered as carbohydrates in the peel of various citrus varieties.

Notes: Paper and ion-exchange chromatography were used to determine qualitatively certain constituents in lyophilized diffusates from cold-water extracts of beef, lamb, and pork muscles. The qualitative contents of low-molecular-weight diffusible organic constituents in tissue from these three species were remarkably similar. Involvement of constituents studied as flavor and odor precursors is discussed.

Notes: Bartlett pear essence was separated by gas chromatography without losing its desirable aroma characteristics. This was done by room-temperature on-column injections, followed by a programmed temperature increase of the chromatographic column. Evidence is presented indicating that the methyl (or other short-chain alcohol moiety) ester of trans-2: cis-4 decadienoic acid is present. Hexyl acetate was identified as a “contributory flavor compound” of Bartlett pear. The infrared spectra of several other esters, which may be “character impact compounds,” are presented, and their correlations with functional groups are discussed.

Notes: Quantitative analyses were made of water-extractable amino nitrogen and carbohydrate constituents of beef, lamb, and pork before and after heating. In all three species, taurine, anserine-carnosine, and alanine were present in relatively large quantities, and losses of these were large during heating. Other important amino acids degraded during heating were: glutamic acid, glycine, lysine, serine, cystine, methionine, leucine, isoleucine, and methyl histidine. Heating caused marked increases of phosphoethanolamine in samples from the three animal species studied. Ribose was the carbohydrate most labile to heating, and glucose was the most stable. The importance of these constituents as odor and/or flavor precursors of meat is discussed.

Notes: Methods are described for the determination of α-tocopherol and γ-tocopherol in margarine by column and paper chromatography and spectrophotometric measurement of the tocopherols. Thirty-seven samples of Norwegian margarine, average values 52 μg/g α-tocopherol and 89 μg/g γ-tocopherol, together with 18 samples from other European countries, were assayed. Ten of the samples were further assayed after 7 months of storage, and showed average losses of 20% of α-tocopherol and 14% of γ-tocopherol. Analyses carried out on 8 samples of hydrogenated fats gave tocopherol values up to the level of original oils, indicating that the hydrogenation step itself does not destroy the tocopherols. Lastly, 7 samples of mixed fat for margarine production were assayed, and gave values somewhat higher than those calculated from the margarine values, indicating some loss during margarine production.

Notes: The biuret method of protein estimation was compared with the Kjeldahl method. Highly significant positive correlations with Kjeldahl protein of 0.99, 0.99, 0.98, and 0.99 were obtained for ground beef, pork, chicken breast, and cod, respectively. The high correlations between the two methods and the small standard deviations for the biuret values point out the reliability and the accuracy of the biuret method. The same substances were analyzed by the Orange G dye-binding method with highly significant positive correlations with Kjeldahl protein of 0.90, 0.80, 0.94, and 0.95 for ground beef, pork, chicken breast, and cod, respectively. However, the amount of dye bound per g protein varies with the protein content of the sample, and the precision is poor. Orange G dye binding has possibilities for use in analyzing meat proteins only if the preparations and procedures are carefully standardized and the protein content does not vary more than a few percent. With Amido Black 10B, the amount of dye bound was too strongly dependent upon sample size to justify further investigation of this dye for estimation of the protein content of comminuted meats.

Notes: Blended mixtures of meat and water containing different concentrations of NaCl were stored for 24 hr at 3°C and further stored for 1 hr at either 3 or 70°C. Then water, nitrogen, chloride, pH, sodium, potassium, calcium, magnesium, and zinc were determined in aqueous extracts obtained by centrifugation. The results show that little or no sodium, potassium, or chloride was bound at 3 and 70°C. At 3°C, the addition of NaCl resulted in an increase of free calcium, magnesium, and, to a lesser extent, zinc. On heating at 70°C, with no added NaCl, all of the magnesium was free, soluble calcium increased, and zinc decreased. At 70°C, on addition of NaCl, free calcium increased and zinc decreased. Zinc was the only electrolyte that was substantially and strongly associated or bound with soluble protein.

Notes: The principal source of the dry chili of commerce in India is Capsicum annuum, variety acuminatum. The oleoresin capsaicin, which is the alcoholic fraction of the ether extract of chilies, is the active ingredient of several essences and medicinal preparations from chilies. In the local variety used, the pericarp, which constitutes nearly 40% of the whole chilies, contains nearly 89% of the capsaicin, while the seeds contain 11%, and the stems only traces of it. Ether is one of the best solvents for extraction of the oleoresin by the percolation method. Since the pericarp contains considerably less fatty oil than the seeds, use of the pericarp for extraction obviates the difficulty of separation of the fatty oil from the oleoresin. The fatty oils, obtained separately from whole chilies and from the seeds, which are bland in taste, have higher acid and iodine values, but lower saponification values, than mustard or groundnut oils. Physicochemical standards have been determined for the oleoresin, fatty oil from whole chilies and fatty oil from the seeds alone.

Notes: Complete reaction of the Girard T reagent with n-alkanals, alk-2-enals, alk-2,4-dienals, and 2-alkanones of carbon chain length up to C-13 was obtained in anhydrous tertiary butyl alcohol. However, in practical applications in the presence of fat these reactions were greatly retarded and inhibited. Modification by the use of water in the reaction gave quantitative recovery of aldehyde homologous series from the fat. Quantitative or even uniform recovery of 2-alkanones could not be obtained. Optimum reaction with the Girard T reagent was at room temperature, and refluxing tended to decrease yields. Girard T hydrazones were. converted quantitatively to 2,4-dinitrophenylhydrizones. The method is useful for the determination of aldehydes generated in autoxidized fats.

Notes: Weanling New Zealand rabbits received a semipurified diet containing either semipurified oleic acid or semipurified linoleic acid, both with and without vitamin E. Rabbits receiving the oleic acid without vitamin E failed to develop skeletal muscle degeneration at 12 weeks, in comparison to marked degeneration at 8 weeks in the comparable group receiving linoleic acid. This would indicate that vitamin E requirements were very low when oleic acid was in the diet. Gallstones, composed largely of cholesterol, were plentiful in rabbits receiving oleic acid at 12 weeks, and a few were noted in rabbits receiving linoleic acid at 8 weeks. The gallstones were slightly more plentiful in females than males, but were not greatly influenced by the vitamin E status. The influence of the dietary fatty acid upon the fatty acid composition of the liver, kidneys, heart, adipose deposits, skeletal muscle, and thoracic aorta was profound. The liver of rabbits receiving oleic acid was slightly less affected than the other organs, while the heart and adipose deposits of rabbits receiving linoleic acid were affected slightly more than the other organs. The sex did not appreciably influence the organ fatty acid percentages. Minor differences in fatty acid percentages were noted between rabbits receiving vitamin E and their deficient counterparts.

Notes: Pectinesterase activity, 3 pectic fractions, and other characteristics were determined periodically on 5 component parts of Pineapple oranges during a 9.month maturation cycle for 2 seasons. Generally, PE activity was greatest in the peel, membrane, and juice sacs in March, April, and May, when the Brix/acid ratio was highest. However, the activity varied in similar components for like months during the 2 seasons. The order of component parts for PE in most cases, from highest to lowest activity, was juice sacs, membrane, peel, seeds, and juice. Total PE in the average whole orange attained maximum activity in March and April. Over 52% of the activity present was found in the juice sacs, which represented about 22.5% of the whole fruit. Water-soluble pectin increased slightly in the peel and membrane, remained somewhat irregular in the juice sacs, and decreased to a constant level in the seeds throughout the growing season. Ammonium-oxalate-soluble pectin in the peel decreased slightly, and in the other components was either irregular or increased slightly, during maturation. Quantity of protopectin was greatest in the membrane and generally decreased toward the end of the sampling period in the various components. Total pectin and weight of the average whole orange was greater in the 1961–62 season than in the preceding season.

Notes: Samples of eight varieties of cowpea, both raw and cooked, were analyzed for their chemical composition and amino acid content by microbiological methods and were also subjected to biological trials with rats in order to determine their nutritive value. Cooking caused losses as follows: 9.2% nitrogen, 17.4% crude fiber, 6270 thiamine, 52% riboflavin, and 45% niacin. With the possible exception of tryptophan, the variation for amino acids was small among all the samples, both cooked and raw, and there was no difference in ether extract and ash. The animal experiments showed marked differences in protein value among the eight samples, even though essential amino acid composition indicated only slight differences. These differences are probably due to variation in amino acid availability. The protein efficiency ratio was higher in the cowpea samples than in the beans. Since cowpeas have a higher nutritive value than common beans, as confirmed in this study, and can be grown under many environmental conditions with higher yields, their use in human feeding should be recommended in developing areas of the world having protein in low quantity and quality.

Notes: A review has been made of published information on the phage groups and types of staphylococci concerned in food-borne intoxication. It revealed that the majority belonged to phage group III with the types 6 and 47, either alone or, with others, being the most common. In Great Britain the yearly incidence of food-borne intoxication, from 1950 to 1962, due to strains of phage group III ranged from 64.5 to 94.7%.In food handlers incriminated in outbreaks the nose was the most common focus of infection, and the hand came next.Meat and milk were the foods most commonly incriminated. Group III phages lysed 64.3% of strains found in meat and 58.1% of those in milk. Group IV phage lysed nine times as many milk-borne as meat-borne strains, which were also quite common in milk taken direct from cows, with and without mastitis or abnormal secretion.The meager data on staphylococcal contamination of “wholesome” food, meat, milk and fish, were tabulated. A high proportion of these strains were untypable, but one-fourth to one-third of the strains were lysed by phages of Group III.The results of phage typing of staphylococci from milk, dairy workers, market milk and dairy products were summarized. Phages obtained from strains of human and animal origin have been used for typing purposes. Of the phages in the “international set” obtained from staphylococci of human origin, 42D, Group IV, lysed more strains than any other phage. A set of phages of bovine origin has not yet been internationally recognized.About two-thirds of the strains obtained from bovine mastitis but three-fourths of strains front normal milk were lysed by the typing phages employed. Group III phages lysed two-and-one-half times as many strains from normal as from mastitis secretion.Cheese, butter, butter-milk, skim milk, cream, ice cream, kefir, and dried and condensed milk have yielded staphylococci lysed mainly by phages of Groups III and IV.Dairy workers, veterinary surgeons, and farmers have yielded strains similarly lysed. Some of the people in these groups as well as the animals they tended have suffered clinical disease processes, due to strains with identical phage reactions.Phage-typable strains have been found in the noses of cattle, in dogs, pigs and chickens; their human attendants have, in some cases, carried identical strains.The proportion of staphylococci, lysed by the 52/52A/80/81 complex of phages has shown a twofold increase in hospitalized human patients and a two-and-one-half increase in animals in the last few years. Staphylococci lysed by this complex are regarded as particularly invasive in and pathogenie for man.No comparison has appeared on the frequency distribution of staphylococci among the phage groups from food-borne intoxication and food handlers. A comparison was therefore made of such reported strains from: i) food causing intoxication; ii) the nose; iii) the feces; and iv) superficial lesions of apparently healthy persons. The main features were: a) the low proportion of strains lysed by phages of Group 111 in ii, iii, and iv; b) the low proportion of untypable strains, especially in i.Systematic phage typing of staphylococci from wholesome food, food incriminated in intoxication outbreaks, hospital patients and the general population in defined geographical areas is recommended. Sites such as the nose, hands, feces, and perineum of healthy people and disease processes in hospitalized patients should be searched for staphylococci, which then should be typed by the use of a standard technique with the aid of the international set of phages from strains of human origin, augmented, where necessary, by phages from strains of animal origin.In addition to the international set of “human” phages, it would be useful to establish and use an international set of phages of animal, especially bovine, origin.Phage typing cannot be used to determine whether a given staphylococcus has produced or can be induced to produce enterotoxin; but is an excellent means of assisting in determining whether staphylococci from victims of food-borne intoxication, suspected food and suspected food handlers are related.

Notes: A correlation was established between the mouthfeel characteristics of gum solutions and their rheological behavior. Gums that are very slimy in the mouth deviate only slightly from Newtonian viscosity. The degree of sliminess decreases with increasing deviations from the Newtonian character, and gums that exhibit a high degree of shear thinning are nonslimy in the mouth. This finding enables selection of proper gums for specific consistency effects by simple reference to the shape of the viscosity vs. the rate-of-shear curve.

Notes: The effects of certain variables on the thermal stability of spinach catalase were investigated with model systems. The rate of thermal inactivation of spinach catalase was accelerated as heating temperature was increased. Inactivation kinetics were not first-order with solutions of the purified enzyme between 50 and 60°C and with spinach extracts at 55°C, hut became first-order with the latter preparation as the temperature was increased to 65°C. The presence of a heat-labile catalase inhibitor is postulated. Catalase was more thermostable in spinch extracts than in solutions of the purified enzyme. Purified spinach catalase at 55°C was more thermostable in solutions at pH 5.5 and 7.0 than at pH 9.0. The thermostahility of purified spinach catalase was not influenced by the enzyme concentration or by the presence of 1.5% NaCl, 3.6% sucrose, or 3.6% starch in pH 7.0 solution at 55°C.

Notes: In an attempt to determine the effect of oxygen and elevated temperature on freeze-dried beef in a moisture-free atmosphere, two series of storage experiments were conducted on freeze-dried beef slices. In one longissimus dorsi muscle, and in the other semitendinosus, was packaged under commercially feasible conditions where the residual gas contained 2.5 ± 0.5% oxygen and no atmospheric moisture. An in-can desiccant, calcium oxide (CaO), and an oxygen scavenger, Oxyban (glucose oxidase), were added in some instances, and the cans were stored up to 6 months at 100°F.In each series there was marked loss in extractability of actomyosin, and in activity of actomyosin ATPase after 1 month, but only a 40% loss of sarcoplasmic proteins. The residual aldolase activity decreased progressively to 8% at 6 months, whereas the residual water-soluble proteins decreased progressively only to 56%. There was a marked difference between the two series in percent rehydration at 6 mouths: 81.1 in one, and only 26 in the second. Electrophoresis of the sarcoplasmic proteins showed gross denaturation after 1 month at 100°F.

Notes: It is shown that the washed muscle fibrils obtained from watery pork have a lower water retention at low ionic strength, and much lower extract-ability at high ionic strength, than the fibrils from normal pork. These changes are accompanied by a gain of protein by the washed watery fibrils, and this protein originates from the soluble sarcoplasmic proteins. All the changes, including the characteristic gain of protein, can be artificially induced in normal meat by allowing it to pass into rigor at 37° C. The isoelectric region, or region of minimum swelling of watery fibrils, whether washed or unwashed, is similar to or slightly lower than that of normal fibrils. There is a broad isoelectric zone in both cases, extending from ∼pH 5 to ∼5.70. On the other hand, the IP of fully coagulated fibrils lies between 5.6 and 6.1. Washed and unwashed fibrils of watery meat show about the same degree of swelling at all pH values. Normal fibrils, however, show a higher water retention in the unwashed state than the washed. This effect is not due to the Mg or Ca ions included in the unwashed samples, but may result from interaction between the sarcoplasmic and fibrillar proteins. In the unwashed state, the swelling of normal fibrils is nearly double that of the watery fibrils at all pH values.It is shown that the rise of pH in intact carcasses of watery meat as they cooled from 37 to 10° C was probably due to the effect of temperature on the pK of ionizable groups of the proteins and buffering substances. It can be reproduced artificially and reversibly in native and coagulated minced meat, merely by raising or lowering the temperature. The titration curves of watery fibrils show similar titration constants (pK') to those of normal fibrils, but a loss of ratable groups. Heat coagulation, on the other hand, results not only in a bigger loss of titratable groups but in a much larger shift in the titration constants. These results can be interpreted to show that the fibrillar proteins of the watery fibrils are not denatured or aggregated in the usual sense, but are probably covered by a layer of denatured sarcoplasmic protein that is firmly-bound to the surface of the myofilaments.

Notes: Volatile compounds in the aroma of five varieties of roasted and unroasted (raw) cocoa beans have been identified by mass spectral analysis and gas chromatography. The five common varieties selected for this study all contain the following compounds usually in this order of abundance: isovaleraldehyde, isobutyraldehyde, propionaldehyde, methyl alcohol, acetaldehyde, methyl acetate, n-butyraldehyde, and diacetyl. An additional eight compounds appear in smaller amounts. As evidenced by gas chromatographic analysis, the raw bean aroma contains the same components but in lower concentrations. The principal differences between varieties are shown to be due to the ratios of these compounds rather than new compounds. The effect of roasting period on the concentration of four aldehydes in the aroma of the ground bean is shown.

Notes: The carotenoids have been examined in the peel and pulp (the edible portion) of Meyer lemons. The principal carotenoid in the pulp was cryptoxanthin. The peel carotenoids included a number of unusual substances, including cryptoxanthin mono- and diepoxides and fractions tentatively identified as hydroxy derivatives of phytoene, phytofluene, and zeta-carotene. An unusual polyene was also found. Apparently it contains two allylic hydroxyl groups, one of which is allylic to the conjugated double bond system.

Notes: An apparatus is described for automatic recording of mechanical resonance curves for test specimens of foodstuffs with the approximate size of 6 × 12 × 50 mm. The simple evaluation procedure described gives information on the modulus of elasticity (divided by the density) and degree of mechanical damping.

Notes: Freshly harvested immature potato tubers contain appreciable amounts of free sugar, mainly as sucrose. As the tuber matures, the percentage of sucrose present decreases and that of starch increases. When stored at 25°C, immature tubers lose sucrose but starch does not accumulate. At 0°C storage, starch content decreases, immature tubers losing starch faster than mature tubers. Free sugars accumulate at O°C, the major one being fructose in immature tubers, whereas sucrose accumulation predominates in the mature tubers.

Notes: Spectrophotometric analyses of aqueous-acetone extracts of frankfurters were useful for characterizing the porphyrin pigments that formed during smokehouse treatment or laboratory heating. The absorption curves showed differences among samples in spectral structure, rates of pigment development, and pigment stability. They also showed promise of differentiating among samples on the basis of storage -stability.

Notes: Amounts of myoglobin and hemoglobin were determined in light and dark muscle of yellowfin tuna, Neothunnus macropterus. Myoglobin concentration ranged from 0.37 to 1.28 mg/g wet weight in light muscle and from 5.3 to 24.4 mg/g in dark muscle; hemoglobin concentrations ranged from 0.12 to 0.58 mg/g in light muscle and from 0.5 to 3.8 mg/g in dark muscle. The fish were divided into two groups on the basis of means of capture, i.e., taken on hooks from a bait boat, or seined. Average percentage of hemoglobin was slightly, but not significantly, higher in the seined fish. Of the total heme pigments, myoglobin constituted 69–85% in light muscle and 81–95% in dark muscle from bait-boat fish, and 47–81% in light muscle and 84–98% in dark muscle of seined fish.

Notes: Sex odor/flavor in pork was produced when fat, lean (with fat), and most organs from a boar were heated in a skillet or in boiling water. Odor seemed not to be entirely absent in boar fat at body temperature, although volatilization appeared to occur to a much greater extent at approx. 100–108° C. Sex odor was found to be water-insoluble, ether-soluble, and definitely associated with the fatty tissues of boars. It was absent in rehydrated moisture-free, fat-free lean. Distillation methods proved unsatisfactory for collecting the sex odor components in recognizable form, since no consistent and reproducible differences could be detected between boar and barrow fat when collected volatile compounds were analyzed by heat test and gas ehromatography. Cold saponification of boar fat yielded a small quantity of unsaponifiable matter that produced a concentrated, permeating sex odor on exposure to heat. Thus, the agent(s) responsible for sex odor in pork are located in the unsaponifiable material. Cholesterol and squalene were found in this fraction in both boar and barrow fat, but sex odor was not produced when these compounds were heated.

Notes: The ability of Tylosin to prevent the growth of coagulase-positive staphylococci was examined in four food substrates. Staphylococcal development was prevented during the organoleptically acceptable shelf life of ice cream mix by 20 ppm of the antibiotic. Staphylococci were controlled in processed cheddar cheese spread, ham, and domestic sausage by 2.5, 3.0, and 5 ppm Tylosin, respectively. The possible use of Tylosin as a preventive of staphylococcal food poisoning in foods is discussed.

Notes: Using the interaction of carrageenan (Seakem type 5) with cetylpyridinium chloride as the type example, investigation was made of optimum conditions for the precipitation of carrageenan and its fractions by quaternary ammonium detergents. Found to be very critical factors for quantitative precipitation were the temperature and pH of the reaction medium. Comparatively, the amount of detergent cation bound by a particular sulfated hydrocolloid is indicative of its degree of sulfation.

Notes: Some tasters were more repeatable than others in making chew counts, and were thereby able to discriminate more between loins of differing tenderness. Mean chew counts by six tasters for 36 loins ranged from 25.3 to 47.0, with one exceptional value at 60.0. These showed a high correlation with mean shear values based on 10 shears per loin. On average, an increase of 1 lb in shear value corresponded to an increase of 4 in the chew count in this experiment. Mean chew counts and shear values both showed significant correlations with two measures of marbling fat made on the 36 loins (visual scores and intramuscular fat contents), the less marbled loins being somewhat tougher. On average, an increase of 1% in intramuscular fat corresponded to a decrease of about 1.5 in chew count or 0.4 lb in shear value.

Notes: Esters are responsible for the typical desirable aroma of Bartlett pear. Hydrolysis products of these esters were resolved by gas chromatography. The major ester acid is an unsaturated 10 carbon acid, which hydrogenates to yield n-capric acid, as identified by relative retention volume and infrared spectroscopy. Nonanoic acid is present in relatively large amounts, and smaller amounts of acetic, propionic, butyric, caproic, and caprylic acids are involved. The major ester alcohols include n-butyl alcohol and n-hexyl alcohol. Two other still unidentified alcohols, possibly polyfunctional or cyclic, occur in large amounts. The author was unable to find evidence of ethyl esters.

Notes: An ionization-detector gas chromatographic unit was used to analyze the acids extracted from a pre-ferment typical of those used in commercial bread-making. At least 45 acids were separated as esters on a column containing an adipate polyester of diethylene glycol. Seventeen of the monocarboxylic acids were identified by relative retention times in free acid form. Their identities were confirmed by preparing and separating their esters directly by flash exchange gas chromatography. The acids thus identified are: formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, crotonic, isocaproic, caproic, heptylic, caprylic, pelargonic, capric, lauric, myristic, and palmitic.

Notes: The lipids extracted from beef and pork muscle were fractionated into triglycerides, cephalins, and a mixture of lecithins and sphingomyelins. The fatty acid composition of these fractions was determined, and the possible effect of phospolipids on meat flavor was evaluated.

Notes: Solubility measurements have shown that the “myosin” of Baltic herring is denatured rapidly in situ even in a 2% sodium chloride solution at 0°C. This denaturation is inhibited by various alkali phosphates and citrate. A higher concentration of sodium chloride requires a higher concentration of phosphate to prevent denaturation by the former. This action of alkali phosphates varies with the pH of the solution, probably as a consequence of changes in the net charge of the proteins and in the dissociation of the phosphates. Possible mechanisms of the inhibiting effect of the phosphates and citrates on the denaturation by sodium chloride are discussed.

Notes: The biochemical and antigenic characteristics of a strain of the Arizona group (1, 2:1, 2, 5) that appears to have been responsible for the illness of 51 nurses in a food-borne outbreak of severe gastroenteritis in an Institution in Washington are described. A custard prepared from fresh, unbroken eggs, was probably the vehicle of the infecting organism. The agglutination reactions of the blood serum of exposed individuals with antigens of several Entero-bacteriaceae, including the Arizona strain isolated during the outbreak, are recounted.

Notes: Part of the lysine was destroyed when soybean meal or isolated soybean protein mixed with sucrose was autoclaved 4 hr at 121°C. Little or no loss occurred when isolated proteins were autoclaved by themselves. In vitro digestion with trypsin and erepsin liberated less lysine from the autoclaved than from the unheated soybean proteins if they did not contain the trypsin inhibitor.Partial hydrolysis with hydrochloric acid liberated more aspartie and glutamic acids and lysine from unheated than from heated soybean proteins.Hydrolysis with concentrated hydrochloric acid for 7 days at 40°C and in vitro digestion with trypsin and erepsin liberated similar amounts of lysine (except for the proteins containing trypsin inhibitors), but acid hydrolysis liberated more aspartic and glutamic acids that did enzymatic hydrolysis.The data support the hypothesis that autoclaving soybean protein formed lysine-aspartic acid and lysine-glutamic acid linkages that were resistant to mild hydrolysis.

Notes: Pelargonidin 3-monoglucoside was isolated from frozen strawberries and subjected to heat degradation in IN HCl. The six fractions isolated were characterized chemically and physically. The unheated and heated pigment inhibited the growth of Escherichia coli and Staphylococcus aureus, and exerted both a stimulatory and inhibitory effect on Lactobacillus casei culture. The stimulation may be due to a decrease in the oxidation-reduction potential of the media affected by the pigment, and/or the ability of the organism to split the β-glyeosyl bond and use the glucose moiety. The influence on growth of the test organisms of the various fractions resulting from heating the pigment was reported.

Notes: Paper chromatography was used in studying variations in the free amino acid content of beef muscle. Analysis of eleven cuts representing nine muscles from a cow shows a variation in the content of certain free amino acids. In general, the variation of the peak of the curve obtained from the chromatogram by a photoelectric densitometer is greatest in the leucine-isoleucine spot. The more tender cuts (Longissimus dorsi and Psoas major) contain more leucine-isoleucine than the less tender Semitendinosus. This was further evidenced in a comparative study of these same muscles from seven beef animals. In each of these seven animals the amounts of these free amino acids increased from the less tender to the more tender muscles. Since the results agree in general with those found by other methods, this study is now being extended to many more animals.

Notes: The proximate composition and sodium and potassium contents of four species of bottom fish from Pacific Coast waters were investigated. Pacific Ocean perch, Pacific cod, and lingcod were quite uniform in composition regardless of species, size, season and area of capture, and method of preservation on board the fishing vessel. The averages were 79-81% moisture, 18-19% protein, 0.5-1.5% oil, 1.1-1.3% ash, 60-70 mg% sodium, and 390-440 mg% potassium. Sablefish varied greatly in oil content, with a range of 3-23% and an average of 15%. Variations in the other constituents were rather large; averages were 71% moisture, 13% protein, 1% ash, 56 mg% sodium, and 348 mg% potassium.

Notes: The lipolytic activity at -7, -18, and -29°C of strains of Pseudomonas fragi, Staphylococcus aureus, Geotrichum candidum, Candida lipolytica, Penicillium roqueforti, and an unidentified Penicillium sp. in emulsions of corn oil, coconut oil, and lard was determined. The action was measured by titratable acidity and by quantitative determination of the fatty acids by chromatography. The lipases from these microorganisms showed considerable activity within 2-4 days at -7°C and within a week at -18°C. Activity at -29°C was evident within 3 weeks by some of the cultures, particularly on corn oil. The rate of lipolysis in frozen substrates was directly related to their degree of unsaturation. However, there also were differences among genera. The lipase of G. candidum had considerably more specificity for oleic and linoleic acids than any of the others. P. fragi and C. lipolytica were least able to attack the β-esterified palmitic acid of lard. The ability of S. aureus to attack this position readily at 35° C was nullified by lowering the temperature to –18° C. A similar effect was observed on the mold lipase.

Notes: The fatty acids in the extracted crude lipid of spinach were studied to determine changes during storage at -17.8°C in the blanched and untreated condition. It was further determined that the total free fatty acids increased in the unblanched samples during storage. Palmitic acid increased during storage, whereas the longer-chain fatty acids, particularly linolenic acid, decreased. A fatty acid containing 17 carbon atoms, n-heptadecanoic acid, was present in fair quantity.

Notes: Katahdin potatoes (1959 crop) were placed in storage at 38°F. Monthly samples were removed and separated into three specific-gravity levels---high, intermediate, and low. Total solids changed but little in storage, indicating that shrinkage is due to a loss of both solids and water in the ratio in the original composition. Total and soluble nitrogen analyses over 10 months demonstrated an inverse relationship between total solids and these constituents when calculated on a moisture-free basis. The nitrogen per gram of fresh weight shows no significant difference between samples of different solids contents. Therefore, the apparent inverse relationship on a moisture-free basis is due to the storage of other constituents, presumed to be principally starch, in the case of high-solids potatoes. About 60-62% of the nitrogen is extracted by 70% by weight ethanol. Subsampling of large lots of potatoes for specific-gravity studies is extremely difficult. All data should be checked for variations from sampling error.

Notes: The colorant of maple sirup has been isolated using ion exchange resins and purified by dialysis. The purified pigment had an empirical formula of C18H27O12N.

Notes: Analysis by gas-liquid chromatography (GLC) of the essential oil from California Valencia oranges revealed over 50 components. A preliminary separation of the intact oil into two major fractions, the terpenes and terpenoids, was made by liquid-solid chromatographic techniques. Examination of the terpene fraction by GLC revealed 15 constituents, of which a number were tentatively identified. The terpenoid fraction contained some 37 constituents, many of which were tentatively identified. These techniques increased resolution and permitted tentative identification of some 14 compounds not hitherto reported in Valencia orange oil. These compounds arc: 3-hepten-l- 01; n-octyl acetate; n-undecanal; hornyl acetate; isopulegol; n-decyl acetate; borneol; citronellol; neral; geranyl acetate; α -pinene; α -phellandrene; γ-terpinene; and p-cymene.The constituents were tentatively identified by calculating relative corrected retention volumes and comparing these with values for known compounds. Two stationary liquid phases used yielded data that lend credence to the tentative assignment of identities of the constituents isolated. In addition, infrared examination of some collected fractions made possible partial identification of the compounds.

Notes: The carotenoid mixtures of the peel and pulp of navel oranges were investigated. The composition of both is qualitatively much like those from Valencia oranges. About half of the total carotenoids in both pulp and peel consisted of violaxanthin and its 5,8-epoxide isomerization products. The peel carotenoids contained a fraction, possibly monol epoxides, in considerably greater quantity than found in Valeneia orange or tangerine peels. This fraction included mono- and diepoxides of cryptoxanthin, and was the best source so far located for a cryptoflavin-like earotenoid previously found in several other fruits. Neoxanthin and a trolliflor-like pigment were found in the pulp of navel oranges.

Notes: An olfactometer is described that will deliver calculated amounts of odor to subjects in a rapid and reproducible manner. It was found that sparging air through a test liquid will saturate the air at the vapor pressure of the liquid. Sensitivities, for a panel, were determined at two levels of acetic acid concentrations; they were 0.939 deviates per mg (× 10−5) per L for a concentration of 1.90 × 10−5 mg per L, and 0.587 deviates per mg (× 10−5) per L for a concentration of 3.37 × 10−5 mg per L. Some modifications of the olfactometer are suggested and discussed.

Notes: This report contains information on some odors produced by gamma irradiation of several beef protein fractions and their derivatives. The odor was shown to vary with protein class, with molecular weight and electric charge, with the medium, and with the availability of functional groups. The unorthodox physical and chemical responses of an odor characterized as a “wet dog” odor are contrasted with those of a “wet chicken feather” odor. Of chief significance is the large variety of irradiated odors that can be produced from a single starting material as conditions are varied.

Notes: The nature of safety factors in canning processes and the uncertainties in calculating lethal values are discussed. The nature, extent, and consequences of these uncertainties are examined. Uncertainties in both the thermal data, obtained from heat penetration measurements, and the bacteriological data contribute significantly to the over-all uncertainty, that in bacteriological data generally being greater. Although experimental error may be large, most of the uncertainty in thermal data is due to real variations from can to can. These uncertainties should be taken into account whenever calculations are made in canning processes, particularly in deciding the safety factor to employ in any particular case.

Notes: Determination was made of the types and quantities of fatty acids released from lard, tallow, corn oil, and coconut oil by lipases from psychrophilic strains of Pseudomonas. The fatty acids were measured by gas chromatography. The rate of fatty acid liberation fell off sharply after the first few hours, but the ratios of the types of fatty acids were not affected until after 24 hours. Additional evidence is presented that much of the palmitic acid in lard is esterified at the beta position. Also discussed is the possible effect of differences in rate of lipolysis of fatty acids from natural substrates on interpretation of their degree of randomness, as measured by enzyme specificity.

Notes: The composition of water-washed yolk granules was different from that of yolk plasma. The lipid content of the granules was about 35%, in contrast to that of plasma (81%). Concentrations of phospholipid, phosphorus-containing protein, and protein nitrogen were not the same for the granules and plasma. A method was developed for the isolation of two ultracentrifugally distinguishable fractions, LPL1, and LPL2, from yolk plasma by a differential flotation procedure. The differences in composition of LPL1 and LPL2 were small but significant. LPL1 contained about 89% lipid, whereas LPL2 was about 86% lipid. LPL1 and LPL2 behaved differently when treated by heat and a proteolytic enzyme. A major yolk steroid, isolated by digitonin precipitation, had a melting point and infrared spectrum similar to those for cholesterol.

Notes: Sarcoplasmic proteins from beef skeletal muscle were fractionated by chromatography on ion-exchange cellulose (cellulose phosphate and diethyl-aminoethyl cellulose) at pH 5 and 9.3. From effluent diagrams of sarcoplasma from muscle immediately after slaughter, at least 14 fractions were recognized, and some of them were identified with known proteins by assays for enzymic activities. The numbers and levels of eluted peaks in the effluent diagram were found to decrease with storage (aging) of muscle and freeze-drying of sarcoplasma; these decreases are perhaps due to denaturation. Proteins in solutions appear to be more completely separated by chromatography when different combinations of ion-exchange cellulose are used.

Notes: A species difference in reactivity of fish muscle proteins toward sodium linolenate in muscle homogenates is demonstrated. The proteins of muscle having higher lipid content show greater stability. Sodium linolenate uptake by natural lipids, resulting in competition between lipids and protein for added sodium linolenate, is suggested. The significance of these findings in terms of a possible in situ relationship of lipid hydrolysis to protein denaturation in frozen stored fish muscle is discussed.

Notes: Frozen fish fillets from commercial outlets representing 26 producers were analyzed for total aerobic plate counts, coliform organisms, fecal streptococci, and eoagulase-positive staphylococci. Total plate counts ranged from 1300 to 1,800,000/g; 72% were below 200,000/g. Coliform counts were low (0–190/ g). Only 14 of the 78 samples contained coliform organisms. Presumptive fecal streptococci counts were usually appreciably higher than coliform counts, and in only a few samples were none found. The highest count noted was 19,000 organisms/g. Coagulase-positive staphylococci were present in 25 Samples, representing 17 producers. Unlike in a previous study on frozen shrimp, half of the egg-yolk-positive micrococci were not coagulase-positive.

Notes: Seven Voges-Proskauer-positive yeasts were isolated from 290 cans of frozen concentrated orange juice representative of the 1962 season's pack. Taxonomy studies of 4 isolates showed the presence of 2 strains of Saccharomyces. Each of the identified yeast strains grew and produced diacetyl in 12° Brix orange juice and 42° Brix orange concentrate, then subsequently removed it. Reagent-grade diacetyl added to a 42° Brix sucrose solution inoculated with one of the test organisms was reduced 95% after 7 days at room temperature. The metabolic process involved in removing diacetyl from a product by yeast is not known.

Notes: The heat resistance of Salmonella typhimurium in liquid whole egg at pH 5.5 and 55°C was reduced significantly by a number of chemical additives. Of these, the most effective were β-propiolactone, ethylene oxide, and butadiene dioxide. Additional advantages of ethylene oxide and β-propiolactone were the elimination of S. typhimurium from heavily inoculated whole-egg slurry during storage at 0°C and a markedly increased lag phase of growth of the test organism in egg incubated at 30°C. Butadiene dioxide, although not tested at 0°C, was most effective in reducing heat resistance at pH 5.5 and 55° C, and also greatly increased the lag phase of the test organism at 30° C. Unfortunately, this latter compound is carcinogenic to mice.Acetic or lactic acid, used to lower the pH of liquid whole eggs, decreased the heat resistance of S. typhimurium more effectively than did hydrochloric acid, especially at pH 5.5 arid 6.0. Formic and propionic acids also were more effective than HCl when all were tested at pH 5.5. Differences in degree of dissociation between hydrochloric and the organic acids are thought to account, in large measure, for these observations.

Notes: The effect of temperature, particularly storage temperature, is one of the most important factors in controlling microbial populations of frozen foods. Adequate temperature control of frozen foods should limit the growth of microorganisms and insure maintenance of original quality and wholesomeness. This investigation was undertaken to show that correct storage temperature; do inhibit the growth of bacteria which might be considered as the source of potential public health hazard, while certain saprophytic species are able to survive and grow well at the same low temperatures. The cultures were all isolated from chicken pies.Bacterial counts were determined by plating techniques on Brain Heart Infusion (BHI) agar after various time intervals up to 30 days at -13°, 0°, 5°, 10°, 20° and 37° C, using both BHI broth and chicken gravy as media. Very similar results were obtained in the two media. Escherichia coli and Streptococcus faecalis had a minimum growth temperature between 5° and 10° C for active reproduction. A minimum growth temperature between 5° and 10° C was observed for the culture of Staphylococcus aureus. Of two cultures representing variants of Pseudomonas fluorescens, one culture followed the growth-temperature pattern shown by the previously mentioned organisms and failed to grow at or below 5° C. The other P. fluorescens culture grew rapidly at 5° C. Ability to grow at low temperatures is a constitutive characteristic of the organism and is not common to all types of bacteria. At refrigerator temperatures, the growth of the psychrophilic saprophytic species tested completely outstripped the growth of several bacteria of public health significance. This indicates the great likelihood that a frozen food on defrosting, particularly in a refrigerator, would become completely unacceptable, due to the development of off flavors and odors and deteriorated physical appearance before it became a health hazard.

Notes: The sensitivity of the pad-plate method for detecting chlortetracycline in egg white is increased by using pH 4.5 citrate buffer rather than pH 4.5 phosphate buffer as a diluent. It is also increased by allowing about four hours for diffusion of antibiotic prior to incubation of the assay plates. Under these conditions of assay, protein binding of the antibiotic was not an important factor.

Notes: Volatile monocarbonyls produced by mildly oxidized esters of oleic, linoleic, linolenic acids and fats have been characterized by paper chromatography of 2,4-dinitrophenylhydrazone derivatives. The unsaturated fatty acid esters yielded a total of 7 n-alkanals, 8 n-alk-2-enals, and 4 alk-2,4-dienals; and similar results were obtained with the fats. Each unsaturated acid produced three major characteristic aldehydes. Comparisons of esters and glycerides showed the presence of keto or aldehyde ester scission products.

Notes: A long-term investigation into the efficacy of different egg preservatives was used to compare different taste-panel techniques. The main contrast is between rating, according to a specified subjective quality scale, and multiple pair comparison, according to flavor preference. A subsidiary contrast is between pair comparison with degrees of preference, and (on the same data) with straight binary preferences. All results are scored, presented graphically, and subjected to an analysis of variance. Pair comparison, especially with (three) degrees of freedom, proved to be more discriminatory than rating. Some aspects of the logic of the comparison of sensory scales are discussed.

Notes: A model system of thin films of lipid supported on dry gelatin plates was used for studying rates of lipoxidation. Variations in the nature of the gelatins used in the supporting surfaces showed significant differences in protective action against lipid oxidation. It is suggested that the observed differences may be due to differences in the orienting effects of the surfaces. Gamma-tocopherol was found to be an effective inhibitor of the oxidation of the films. Synthetic phenolic antioxidants were not nearly as effective. Phospholipid in large concentration was also an effective inhibitor.

Notes: Because of the limited penetrating ability of low-voltage electrons, depth and density are necessarily major considerations in the experimental irradiation of food by this means. In this study, survival of bacteria dispersed in agar was used to indicate the effective amounts of irradiation resulting at various depths from various electron doses to the surface. The per cent survival at each depth was plotted against the dose received as measured by cobalt glass dosimeters located at the same depth. These had been calibrated in terms of dose response by means of gamma radiation delivered by a source accurately calibrated by ferrous dosimetry. Within the 3-cm depth studied, a linear relationship was found between dose and log per cent survival.

Notes: Slices of beef were heated to 130°, 150° and 195° F, irradiated at 0.1 and 5.0 megarads and stored at 34° F. The effect of these variables on free amino nitrogen, total soluble nitrogen and TCA-soluble nitrogen was determined at 15-day intervals during the 60-day storage period. Increases in heating temperature reduced the rate of release of TSN and TCA-soluble fractions. Amino nitrogen was reduced only at highest temperature employed. Irradiation increased the rate of release of these fractions. The release of amino nitrogen began immediately upon storage of raw beef. Major amounts of TSN were not released until after 15 days storage and TCA-soluble nitrogen not until after 45 days storage. This suggests successive fragmentation of the initially bound protein.

Notes: Color data on stored spinach and cauliflower were correlated with judges’scores to determine best sampling procedures for measurements with the Hunter Color and Color-Difference Meter. Spinach stems, rather than leaves or mixtures, changed the most and most uniformly, correlated best with scores, and produced the smallest experimental errors. Cauliflower floret surface, instead of stems or mixture, gave smallest significant differences by judges. Good results on the instrument were obtained for both floret surface and a rapidly prepared slurry from a thin surface layer. Best of six color indices of deterioration were Hunter “a” and hue angle

Notes: The total carotenoid pigments of pineapple fruit contain a high proportion of epoxide groups which are readily isomerized to furanoid forms in an acid but not an alkaline environment. This isomerization causes a characteristic hypsochromic shift in the absorption maxima of the pigment extract. The absorbance at 425 mμ remains relatively unchanged as isomerization proceeds, and thus can serve as a measure of the total carotenoid pigment regardless of its isomeric form. The sharp maximum at 466 mμ is lost as isomerization progresses. Thus, the ratio of absorbances at 466 and 425 mμ can serve as a measure of the extent of isomerization of the pigments.