ALBERT

Notes: Changes were determined in total and water-soluble calcium and magnesium content and in the pectic substances of Bartlett pears during maturation and storage. The data indicate a change in metabolic processes when the fruit is removed from the tree. In maturing fruit, about 48% of calcium and 65% of magnesium are present in soluble form. Both cations generally decreased during maturation. The Mg/Ca ratio varied with growing conditions and may be related to soil composition. The data indicate that mare, total pectin, water-soluble pectin, total calcium, and total magnesium arc correlated with firmness. The relationship of soluble calcium and magnesium to firmness is radically different in detached fruit from that in fruit on the tree. Analyses of data indicate that the “bound” calcium and magnesium are present in concentrations far greater than the total available carboxyl groups of pectin, and that protopecin content is not related to calcium- or magnesium-bound pectinic acid chains. In detaching ripening fruit, when a general breakdown begins there is a good correlation of all data with firmness.

Notes: An apparatus was developed to study the extensibility and elasticity characteristics of muscle fibers before and during the onset of rigor mortis. A variable load (weight) was applied to a muscle specimen held in a chamber under controlled conditions maintained by a thermostatically regulated cartridge heater, cooling coil, and gas inlet. A solenoid cell, energized by a cyclic timer, was used to release and apply the load in a direction longitudinal to the vertically mounted specimen. A lever attached to the specimen-loading, system transmitted the extensibility and elasticity of the specimen to the armature of a differential transformer. The output voltage, from the secondary transformer winding was directly proportional to displacement of the armature. This AC output signal was rectified and transferred to a DC recording microammeter. The time course of rigor mortis was not influenced by loading and unloading interval or size of muscle strip, and was found to be temperature-dependent, being prolonged as temperature was decreased. The white fibers of the semitendinosus muscle were found to have a considerably longer delay phase than the red fibers. The relations between the time course of rigor mortis and the ultimate properties of the muscle were discussed.

Notes: The sodium 2,6-dichlorohenzenoneindophenol method (Method A) and the diazotized 4-methoxy-2-nitroaniline method (Method B) for measuring reduced ascorbic acid in frozen peas were compared. A randomized incomplete block design with 12 replications for each of the two methods of ascorbic acid analysis was used. Very highly significant differences in ascorbic acid values were obtained between Methods A and B, with Method A always the higher.

Notes: Variations in the apparent dissociation constants of ethyl acetate for several different samples of banana pulp are noted. It is hypothesized that the variations might he due to the involvement of coupled reactions that supply or delete one or more of the reacting species at a rate faster than that at which the tissue esterases function to establish equilibrium. In the same samples, the constants for methyl acetate and iso-amyl acetate remained relatively constant.

Notes: This paper describes the separation and partial identification of 10 volatile fatty acids present in apple wine. The acidic fraction was prepared by “stripping” the wine in a rising film evaporator and separating the volatile acids from the strippings by appropriate pH adjustment, steam distillation and extraction. When the volatile acids of apple wine were examined by gas chromatography, using Ucon 50-HB-2000 and Uconnonpolar, ten distinct peaks were revealed. In addition the volatile acids were methylated with diazomethane, and the composition of the methyl ester fractions was studied by gas chromatography using diethylene glycol succinate and Carbowax-400.

Notes: Two related glycoflavones (flavonoids A and B) have been isolated from commercial wheat germ samples, where they occur to the extent of some Q.2–0.3%. Each consists of an apigenin nucleus to which is attached a highly hydroxylated glycosyl-type side chain. Evidence from ultraviolet spectrophotometric studies and from similarities with known glycoflavones suggests that the side chain is in the & position. Short hydrolysis of flavonoid A splits off a molecule of sinapic acid, leaving flavonoid B, while more prolonged mineral acid treatment of both flavonoids leads to partial formation of a third glycoflavoue. In addition to the glycoflavones, ferulic acid and vanillic acid have been found in wheat germ in the free form. The presence of a methoxy hydroquinone glycoside has also been indicated.

Notes: With increase in temperature (61, 80, and 100°C), scores for ease of fragmentation and lack of adhesion between muscle fibers trended toward greater toughness in longissimus dorsi (LD) and toward greater tenderness in biceps femoris (BF). Of the two muscles, RF was the more easily fragmented and had less adhesion between muscle fibers at 80 and 100°C. Mealiness was not present at 61°C, but tended to be greater at 100 than at 80°C. BF was considerably more mealy than LD. These changes in tenderness are considered in relation to chemical and histological changes during aging reported by others.

Notes: Replicated scorings of 4 series of wines were made by 8 tasters with two different designs of presentation. Design 1 consisted of different wines with additives (each wine with four concentrations of additives was tasted as a block) and design 2 consisted of randomization of tastings over all wines and additives. In any one design, tasters did not react the same for any given series. The differences showed up in both mean scorings and in the variability of the scorings. When the design was broadened to include more diverse categories in a randomized fashion, the scorings became biased in rather unpredictable ways and the variability of the scorings increased in general, in some cases.

Notes: The taste interaction of suprathreshold solutions of sucrose and sodium chloride was determined by highly trained subjects using single- and paired-sample presentations. With both methods, the apparent saltiness of 0.12–3.240 sodium chloride was reduced by sucrose. In general, the sweetness of 0.75, 2.25, and 6.75% sucrose was enhanced by lower, and depressed by higher, salt additions. All levels of salt depressed the sweetness of 20.25% sucrose. Response to sweetness and saltiness varied with method of presentation. There was a large amount of variation in scoring attributable to differences between judges, hut reproducibility of judgment was much greater in the paired- than in the single-stimulus method.

Notes: Antibiotic activity in aged Liederkranz cheese was found to be produced by the aerobic microorganisms inhabiting its surface. Brevibacterium linens was the principal source of the antimicrobial agent(s). Yeast of the Candida type and, when present, some other microorganisms contributed minor antimicrobial activity. The antimicrobial agent(s) of aged Liederkranz cheese had the following properties: 1) dialysable through cellulose casing, 2) absorbed on Norit A at acid pH, 3) stable in acid and alkaline solutions ranging from pH 2.0 to 12.0 at 24° C, 4) destroyed within 20 hr in alkaline solution at pH 12 at room temperature, 5) in aqueous solution stable to heating at 121° C for 10 min at acid pH(pH〈5.0) but decreased activity at pH 5.0 to 8.5, 6) in agar medium of pH 6.8–7.0 activity remained after heating at 121° C for 45 min, 7) soluble in water, methanol, ethanol, and butanol, slightly soluble in acetone and insoluble in ethyl ether, carbon tetrachloride, chloroform and ethyl acetate, 8) inhibited growth of many gram-positive and gram-negative bacteria as well as several yeasts and molds, and 9) related to antibiotic from B. linens but distinct from nisin, an antibiotic commonly associated with dairy products. In a survey of market samples of cheeses to determine whether antibiotic activity was present, only surface-ripened cheeses with a brown smear made up of bacteria were found to contain antibacterial activity. Other types of cheeses which did not develop this brown smear did not possess this activity. It may be concluded that antibiotic activity is contained in the brown bacterial surface smear that develops during ripening.

Notes: The rate of browning of 20 sugars or sugar derivatives was followed by reflectance measurements of cookies and spectrophotometric measurements of browning of dilute buffered solutions of the sugars and glycine or lysine, heated at 114°C in an autoclave. Both in cookies and in solution, the order of decreasing reactivity for the pentoses was: ribose, xylose, and arabinose. Among the hexoses, galactose was the most reactive and rhamnose the least. Because the conditions of pH and presence of amino acids were varied, no over-all order of reactivity could be established for the other hexoses. Disaccharides with reducing groups, except melibiose, showed little reactivity. Sugars without reducing groups failed to exhibit browning.

Notes: Absolute taste thresholds for salt and sweetness were determined by a combination of ascending-series and rating-scale methods: for salt a value only very slightly under previous quoted figures was obtained, for sugar a value of .002 p/p was obtained. The results also permitted a scaling of each taste description on the rating-scales in terms of both j.n.d's above threshold and solution concentrations. Previous workers have doubted whether there is one single absolute threshold for taste: the present results suggest a number of thresholds in an ascending series may be defined operationally.

Notes: Efforts were continued in an attempt to assess quantitatively the behavior of certain cellular components while the spores were being exposed to moist heat, and to correlate such behavior with the thermal death reaction.Spores of Bacillus subtilis were preheated over prolonged intervals in an attempt to induce the release of cellular dipicolinic acid (DPA) without exercising serious loss of viability, and then to evaluate the subsequent effect of DPA release upon the thermal death rate of the preheated spores. At 45°C in 2.5mM PO4 buffer at pH 7, the net DPA released amounted only to 1.6 and 2.7% at the end of 20 and 30 hr. The treated spores exhibited no loss in viability and when heated at 98.5°C in 25mM PO4 buffer at pH 7, exhibited no differenee in their thermal death rates. Prolonging the heat treatment up to 9 days did not materially change the final results. To induce faster and greater DPA release, the above experiment was repeated at 80 and 90°C. At 80°C the net DPA released was 3.6 and 4.1% at the end of 3 and 8.5 hr, without loss in viability. However, the treated spores exhibited some reduction in their thermoresistance at 98.5°C. At 90°C greater amounts of DPA were released, but were associated with substantial loss in viability, and the surviving spores exhibited marked reduction in their thermoresistance at 98.5°C. These observations suggest the existence of DPA in more than one structural form; free or loosely bound to the spore structure and easily exuded upon mild heating or even standing under refrigeration; and a second more strongly bound form which required severe heating for its release. It is this latter form which might be associated with the mechanism of thermoresistance. Along with DPA, following the same pattern but at much higher rates, ninhydrin-positive material was exuded during sublethal heating at 80, 85, and 90°C. It was suggested that such material might be of similar nature to that exuded during germination of Bacillus species as described by Powell (1957).Spore suspensions of Bacillus coagulans (thermoacidurans) of varied thermostability were heated in 25mM phosphate buffer at pH 7, at 95°C and both the rate of death and DPA release were established. Results showed a difference in kinetics between the two reactions. Death progressed at higher rates than DPA release. Higher rates of death were associated with higher rates of DPA release. Spores of same strain were heated in both water and 10mM glyeylglycine, a death accelerating agent, at 100°C, sampled at intervals and analyzed for survival, dry weight, calcium, manganese, magnesium and DPA. Results showed the death of spores and their concurrent exudation of DPA and divalent cations were both markedly accelerated in the presence of glycylglyeine. The 25-min survival and exudate levels in glycylglyeine were near equivalent to those at the 65-min levels in water.The kinetics of death and the concurrent release of DPA and calcium were further assessed in more detail in 5mM phosphate buffer at pH 7 at 96 and 99°C using spores of B. coagulans (thermoacidurans). Death again progressed at a higher rate than that of either DPA or calcium release. Based on the molar ratio of Ca/DPA released in the supernataut, the initial ratio was always greater than 1, then rapidly dropped. and eventually plateaued at a value of less than 1. Similar patterns of death and calcium and DPA release were obtained for B. cereus when heated at 86°C.All of the above observations demonstrate the association of the thermal death reaction with the exudation of ninhydrin-positive material, DPA and divalent cations into the heating menstruum. The exact relationship between such cellular components and the spore mechanism of thermoresistance remains inconclusive.

Notes: The regeneration of spinach catalase was demonstrated during storage after heat inactivation. The occurrence of regeneration was influenced by the enzyme source, pH, heating conditions, and storage conditions. The change in catalase activity after heating was considered to represent the balance between enzyme regeneration and enzyme inactivation during storage.

Notes: Nona-2, 6-dienal, non-2-enal, hex-2-enal, and three saturated aliphatic aldehydes were isolated from cucumbers. Quantitative and qualitative aspects of the flavor of nona-2,6-dienal and non-2-enal were examined.

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: The concentrations of 27 trace elements were determined in four meats: beef, pork, ham, and chicken. Because the concentrations of most of these elements were expected to be very small, the extremely sensitive method of neutron activation analysis was used in this study. Qualitative analyses were performed for 8 of the elements, and the concentrations of 19 elements were determined quantitatively. The quantitatively measured concentrations varied from ∼0.1% for phosphorus to ∼10−5 ppm for cerium. Most data are estimated to be accurate to ±10%. The results demonstrate the applicability of this analytical method to determination of the inorganic constituents in foods and related substances at a constant level of accuracy throughout the concentration ranges of practical interest.

Notes: Total lipids, lipid phosphorus, and total polyenes extracted from mullet tissues with chloroform-methanol show a progressive decrease in oxidizing mullet tissue. Thiobarbituric acid values from chloroform-methanol extracts of oxidized tissues are approx 30–50% of those obtained from the unextracted tissue. Much of the TBA-reactive material becomes concentrated in the inter-facial fluff during the washing of such extracts. Chloroform alone extracts only about 10% of the TBA-reactive material.

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 olfactometer described previously was modified and used to determine odor-difference thresholds for 48 subjects at 4 levels of 2-heptanone. The apparatus was found to give rapid and reproducible threshold measurements. Difference thresholds were found to follow the Weber law. A Weber fraction of 0.23 mg/min/deviate was determined for 2-heptanone. The absolute threshold was found to be 8.97 × 10−4 mg of 2-heptanone/L air.

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: The distribution of nineteen amino acids was found to he almost identical in Longissimus dorsi from a normal pig and a pig affected with total muscle degeneration.

Notes: An improved method for measuring sorbic acid in cider is based on dilution of the sample and direct ultraviolet readings at 262 mμ This method was compared with the distillation method for sorbic acid usually applied to cider. The latter method produced ultraviolet-absorbant materials that interfered with sorbic acid determinations and were shown to he affected by the sugar content of the cider and the distillation techniques. The ultraviolet-interfering materials in cider distillates have absorption peaks and chemical properties similar to those of 5-hydroxymethylfurfural.

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: Anserine (β-alanyl-L-1-methylhistidine) is cleaved hydrolytically by a haddock muscle enzyme. The inclusion of chlortetracycline and oxytetracycline in ice preserving eviscerated haddock increases the free β-alanine and L-l-methylhistidine recoverable from the muscle during chill storage. This results from their lower utilization by the microfloras selected by tetracyclines. Technological implications are discussed briefly.

Notes: The radiation resistance of spores of 6 strains of Type E Clostridium botulinum was determined in a beef stew substrate. The results are evaluated in terms of the minimum dose showing no spoilage for a 2 billion total inoculum level (20 cans each with 100 million spores per can) and in terms of a calculated radiation D value. The mean radiation D value for 6 strains is 0.132 megarad (range 0.125–0.138). A comparison with results for 6 strains of Type A and 5 strains of Type B shows that Type E strains possess about 45–5570 of the resistance to ionizing radiations of Types A and B. It is concluded that any radiation dose for food sterilization based upon the maximum resistance of Type A or B strains would provide ample protection against Type E strains. The unswelled cans at the lowest radiation level showing no spoilage were free of toxin and recoverable Type E spores.

Notes: A method for estimating the total monoterpene hydrocarbon content of citrus oils is described. The procedure consists of adding an internal standard (n-butylbenzene) to the oils, spotting the mixture on a chromatostrip, eluting the hydrocarbons, and analyzing the eluate by gas chromatography. The total monoterpene hydrocarbon content is calculated from the weights of n-butyl-benzene and citrus oil used and from the areas under the peaks of the monoterpene hydrocarbons and n-butylbenzene on the chromatogram. The average percent total monoterpene hydrocarbon content and the standard deviation are given for a selected number of citrus oils. Data also show the relative monoterpene hydrocarbon composition of these oils.

Notes: The monoterpene hydrocarbon composition of 29 non-citrus essential oils was determined with silicic acid chromatostrips and gas-liquid chromatography. Data arc presented showing the total monoterpene hydrocarbon content and the relative proportions of 19 of these compounds in each oil.

Notes: Studies were carried out on the fractionation and analysis of egg lipid by several new techniques employing thin-layer chromatography. The fatty acid composition of the major lipid classes and subfractions thereof was determined by a combination of alkali-isomerization and gas-liquid chromatography. The positional arrangements of the fatty acids in the glycerides and lecithin fraction were determined. The fatty acids in lecithin were distributed mainly in one type, the α-saturated β-unsaturated type, in contrast to the fatty acids of triglycerides.

Notes: This paper reports work related to scores for juiciness and two components of tenderness: softness to tongue and cheek, and softness to tooth pressure. As steak temperature increased from 61 to 80°C the meat became drier and harder, hut more markedly in biceps femoris than longissimus dorsi. From 80 to 100°C, longissimus dorsi became still drier and harder; biceps femoris also became drier but did not change in softness to tongue and cheek and became softer to tooth pressure. These changes were studied in relation to cooking times and weight losses during cooking; to percent loss of water from raw meat; and to the size and possible hydration of muscle fibers. Correlations calculated on a lot-muscle-temperature basis indicated that juiciness was not closely associated with any of the six components of tenderness. The closest was softness to tongue and cheek, which accounted for about 35% of the variation in biceps femoris at 80°C. The results are discussed in relation to theories of tendering or toughening.

Notes: An attempt was made to develop an assay procedure for staphylococcal enterotoxin based on the possible induction of eytopathogenic effects on several strains of tissue culture cells using enterotorin preparations of varying degrees of purity produced in a laboratory medium. The results suggest that the cruder preparations contained a thermolabile cytotoxic material that is removed in whole or in part with progressive purification. No observable cytopathogenic effect could he attributed directly to the enterotoxin.

Notes: Sixteen compounds in the volatile fraction of apple wine were isolated and identified. Ethyl chloride was preferred over pentane or iso-pentane in extraction of the volatiles because it gave higher yields and its lower boiling point allowed almost solvent-free extracts in a very short time. Gas-liquid chromatography was used in separation and purification of the volatiles. The compounds were identified by comparing retention times, infrared spectra, and melting point of derivatives with those of known compounds.

Notes: A simple, direct calorimetric method requiring no distillation is described for the determination of potassium sorbate in dried fruits. The method makes use of the oxidation of sorbic acid to malonaldehyde, which reacts with thiobarbituric acid to form a red pigment that is measured photometrically.

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: Studies were carried out to determine the best combination of rice and cooked black beans when one partially replaced the other isonitrogenously. Experiments with young and with adult protein-depleted rats indicate that the best combination was one in which about 60% of the protein of the diet is from rice and 40% from black beans. The range of values was from 70 to 50% rice and from 30 to 50% cooked black beans. The median figures correspond to 80 g of rice and 20 g of beans. On an isoproteic basis, rice protein is superior to black bean protein, and supplementation of either protein source with known limiting amino acids improved the protein value. Cooked black beans supplemented with methionine and valine still did not induce as good growth as rice supplemented with lysine and threonine. When rice-black bean diets containing 50% protein from each source were supplemented stepwise with the limiting amino acids methionine, lysine, and leucine, the growth and feed and protein efficiencies of the rats improved; serum protein and liver fat tended to increase.

Notes: A fungal enzyme preparation, “Naringinase C-100,” was separated by paper electrophoresis into individual rhamnosidase and glucosidase fractions. The specificities of these fractions were determined by testing their ability to hydrolyze various flavonoid and related phenolic glycosides. The individual rhamnosidase and glucosidase fractions were characterized by determining the degree of hydrolysis produced in standard naringin and prunin substrate solutions at various pH's, temperatures, and time intervals. A paper chromatographic-fluorometric method suitable for quantitative determination of naringin and prunin in mixtures containing naringin, prunin, and naringenin was devised and employed in the characterization studies.

Notes: Studies were continued on the tannin in Muscadine grape leaves previously reported to have inhibitory activity toward peetinase and cellnlase. The tannin was isolated and purified by precipitation with caffeine and recovery by chloroform extraction. The material is a light tan, and in the freeze-dried form is quite bulky. It is a condensed tannin of high molecular weight, producing a large percentage of phlobaphenes upon acid treatment. The soluble portion after acid treatment was shown to contain gallic acid and glucose in small amounts.

Notes: Infrared spectra for a number of commercial types of pectic substances were determined with a film technique used elsewhere on gums and pectin. It is possible to distinguish between pectins with high methoxyl and with low methoxyl and polygalacturonic acid. Although the spectrum for the only apple pectin examined differed in some respects, particularly at longer wavelengths, from citrus peetin spectra, additional samples should be examined with higher resolution before conclusions are made about fruit sources. Results now reported should be of use in general qualitative identification of pectic substances. Improvements in equipment and techniques are suggested.

Notes: Analyses are presented of the vitamin A, vitamin C, and iron content and proximate composition of raw variety meats from beef, calf, lamb, and pork. Vitamin A content of liver varied considerably from reported values. Extreme variations within different liver samples were also observed. Lamb liver contained the largest amounts of vitamin A of any of the samples tested. Small amounts were found in kidney and lamb lung. Vitamin C content was greatest in calf and beef thymus.

Notes: Panel scores for juiciness and six components of tenderness were considered in relation to possible multiple causes of tenderness or toughness and to certain histological, chemical, and physical data. One-inch steaks from Longissimus dorsi and biceps femoris from 180 young cattle in nine lots were eooked to 61°C (rare) and to 80°C (well-done) by dry heat, and to 100°C by moist heat. Connective tissue in longissimus dorsi was scored tender at 61°C, and was tendered only slightly by increases in temperature, whereas in biceps femoris it was scored tough at 61°C and became progressively more tender at 80 and 100°C. Collagen content was greater in biceps femoris than in Longissimus dorsi at 61 and 80°C, but there was little difference in the two muscles at 100°C; the losses in both muscles increased with increasing meat temperatures. The relation of panel scores for tenderness of connective tissue to collagen content and to the loss of collagen on heating is discussed.

Notes: Small concentrations of linoleic and linolenic acids reduced the solubility of cod actomyosin rapidly. The extent of insolubilization depended on the structure of the fatty acid, on its concentration, and on the duration of storage of the fatty-acid-treated actomyosin solutions. The results support the hypothesis that the accumulation of free fatty acids in frozen fish muscle causes the actomyosin of the muscle to become inextractable.

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: Free amino acids were determined in the juices of mature Valencia and Washington navel oranges, Eureka and Lisbon lemons, Dancy taugerines, and Marsh grapefruit. Twelve amino acids and ammonia were identified and measured quantitatively. Eleven unidentified ninhydrin-positive compounds were also'detected. Alanine, asparagine, aspartic acid, glutamic acid, proline, set-me, γ-aminobutyric acid, and arginine occurred in substantial amounts in all fruits. Proline was the most prominent amino acid in every fruit except the grapefruit, hut appeared in especially high concentrations in the Valencia orange. Aspartic acid predominated in the grapefruit. Nitrogen calculated from the amino acids accounted for approximately 70% of the Kjeldahl nitrogen in each of the juices.

Notes: Lipoxidase demonstrated a typical protein inactivation response to heat as a function of pH when heated at 65°C and 0.1 molar buffer. The enzyme was found to be very sensitive to ionizing energy when irradiated in pH 7 buffer. This sensitivity was shown by a relatively low D, value (9 × 104 rad) and a rapid loss of enzyme activity during post-irradiation storage. The results of combined treatment of the enzyme, in buffer, by heat and radiation showed that treatment order was important. Heating prior to irradiation produced inactivation proportional to the sum of the separate treatments, whereas the reverse order produced inactivation greater than that calculated from the effect of each treatment. This is in agreement with the above, where post-irradiation storage at 0°C may be likened to a mild heat treatment. Addition of 20% pea solids to a. buffered solution of the enzyme afforded a six to ten fold protection with respect to inactivation by heat, and a seventy fold protection against inactivation by ionizing radiation. Combined heat and irradiation treatment of soybean lipoxidase, in the presence of 20% pea solids, showed that, in contrast to the results obtained in buffer, heat prior to irradiation produced greater enzyme inactivation than the reverse order of application of the two types of energy.

Notes: A kinetic procedure employing D values was used instead of the usual end-point method to study heat inactivation of peroxidase in whole-kernel sweet corn. Results at 150–200°F indicated that a heat-labile fraction and a heat-stable fraction were being inactivated. The resistant fraction represented 5% of total enzyme activity, and was concentrated in the pericarp. Increasing the blanch time at 200°F from 2 to 5 min decreased residual enzyme activity from 3.3% to 1.7%.Inactivation of the heat-resistant fraction at 210–290°F also followed a first-order reaction. The phantom inactivation-time curve showed that an HTST process based on microbial destruction could leave residual enzyme activity.

Notes: Five fractions of parenchymatous cells of the cotyledon of the peanut were isolated by homogenization and differential centrifugation from nonaqueous media. These are two protein-rich fractions (one of which appears to be aleurone grains), starch grains, a fines material, and cell wall fragments. In addition, a fraction composed largely of vascular tissue of the cotyledon was isolated. The nitrogen of the cell is concentrated in the two protein-rich fractions, phytin in the aleurone grains, sucrose mostly in the fines fraction and to a lesser extent in the starch granules, and ribonucleic acid in the fines fraction. The proteins in both protein-rich fractions appear to be the same as judged by chromatography and zone electrophoresis.

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: 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 stability of low levels of the antifungal pimaricin in orange juice can be quantitatively followed by a cylinder-plate agar assay using a strain of Saccharomyces cerevisiae that is sensitive to 0.6 μg/ml. Pimaricin is stable in orange juice stored in the dark under refrigeration. The assay data indicate that pimaricin is adsorbed or bound to the juice pulp, and the recovery from the juice depends upon proper sample dilution.

Notes: The protein in wholewheat unbaked bread ingredients, microwave-baked wholewheat bread, oven-baked wholewheat bread, and two breakfast cereals was evaluated by gain in body weight of rats, protein efficiency ratio, increase in carcass nitrogen, and apparent availability of lysine as determined by fecal excretion.No significant differences were noted between the bread ingredients and microwave-baked bread. Oven-baked bread gave values significantly lower, 24–45%, than those of the ingredients. The apparent availability of lysine in bread ingredients and in microwave-baked bread was 96% and 95%, respectively, whereas that for oven-baked bread was 70%.The protein in one breakfast cereal barely maintained the weight of the animals, and gave low values for protein efficiency ratio and increase in carcass nitrogen. Seventy-five percent of the lysine was available. The other cereal allowed good growth of the animals and gave values similar to those for nonfat milk. In this oat-and-wheat-germ cereal, 88% of the lysine was available.A linear relation was obtained between either gain in body weight or increase in body nitrogen and the amount of available lysine ingested.

Notes: Color development was maximum at a 2:l stoichiometric ratio of dihydroxyacetone to arginine when both the molar-ratio and Job's methods were applied to solutions maintained at a pH 6.3–6.5. The reactants, which produced the red-brown color through a series of chemical changes, gave reprodueihle absorbance data at 300 mμ for solutions containing a final concentration of 2–120 ppm of dihydroxyacetone.

Notes: Pectinesterase activity, 3 pectic fractions, and other characteristics were determined periodically on 5 component parts of Valencia oranges during a 7-month maturation cycle for 2 seasons. Usually, PE activity for peel, membrane, and juice sacs was least in December, when the Brix/acid ratio was low, and highest in June, when this ratio was greatest. The order of component parts for PE in most cases, from highest to lowest activity, was juice sacs, membrane, peel, seeds, and juice. Water-soluble pectin generally remained constant in peel and juice sacs, increased slightly and then remained constant in the membrane, and was irregular throughout the cycle in the seeds. The trend of ammonium-oxalate-soluble pectin in the components was to increase during maturation. Protopectin in the component parts usually increased to a peak and then gradually decreased for the remainder of the season, except that protopectin in the juice sacs decreased throughout the sampling period. In this component, protopectin evidently was at its maximum by the first picking in December. Total pectin remained constant in the juice and seeds, and slowly declined in the other 3 components with maturation. Membrane contained the highest source of protopectin and total pectin throughout the season.

Notes: Different buffer systems were compared for efficiency of extraction of chicken muscle proteins, and a technique was developed for routine fractionation and estimation of major protein fractions in one operation. KCl-borate and KCI-phosphate buffers of pH 7.3–7.5 and r/2 = 1.0 gave maximum extraction, with a reproducibility of ± 22%. Protein fractionation in KCl-borate buffer showed that in one-year-old chicken meat, stroma-myofibrillar-, and sarcoplasmic-protein nitrogen respectively contributed 13, 42, and 30% of total nitrogen in breast muscle, and 27, 30, and 22% in leg muscle. Results with different chickens showed that, with increase of age, stroma increased and myofibril decreased in both breast and leg muscle. These two protein fractions also differed for breast and leg muscle, and varied with the source of supply of the chickens. The difference was small between birds of the same flock and between left and right halves of the same bird.

Notes: Reticulataxanthin and tangeraxanthin were obtained from tangerine peel; both occurred in the diol fraction on countercurrent distribution, and on chromatography were found on the column above zeaxanthin as violet-red and violet bands, respectively. Both contained a carbonyl group as a part of the conjugated-double-bond system. Reticulataxanthin was shown to be different from capsanthin, hydroxycanthaxanthin, and citraurin. Both of these carbonyl earotenoids apparently contained fewer than 40 carbon atoms, perhaps 34 or 35.

Notes: In the flesh of certain species of fish, autolytic hydrolysis of some lipids may he totally inhibited. Examples are the hydrolysis of triglycerides in herring and of phospholipids in dogfish. In other cases an initially slow rate of hydrolysis of phospholipids may be followed by a faster rate. Such initial partial inhibition is exhibited, for example, in cod flesh maintained at 0°C. This initial “lag” may be abolished by freezing at either a very fast or a very slow rate, followed by thawing, but not by freezing at an intermediate rate. No comparable lag has been observed in fish maintained in the frozen state at any temperature, regardless of freezing rate. In unfrozen cod, or in cod maintained at −7°C and below, a terminal inhibition to the “rapid” phase becomes evident at about 75% hydrolysis of the total phospholipids, and this is followed by extremely slow further breakdown. At −2.5 to −4.7°, however, the “rapid” phase appears to proceed to completion. Hydrolysis of phospholipids is promoted by the frozen state in two ways: a) abolition of any initial lag, b) increase of reaction rate. The reaction rate passes through a maximum at about −4°C and even at −7°C is faster than at 0°C.

Notes: Color changes in disrupted tissue of red beets were studied under various conditions with a Hunter color and color-difference meter. Results showed that both autoxidation and enzyme-catalyzed oxidation of brown-pigment precursors were responsible for the darkening of beet tissue. Histochemical studies on the localization of phenolase in red, beets showed that the vascular tissue was the major site of enzyme activity. Apparently, the cell walls contained a small amount of phenolase. High phenolase activity was observed in both a beet extract and washed pulp of beets. Data are presented on the optimum pH and substrate specificity of beet phenolase. A solution containing 2% sodium carbonate and 5% sodium chloride was found to be a good solvent for extraction of the phenolase from washed beet pulp. At least four phenolic compounds were separated by paper chromatography.

Notes: A method was developed for estimation of chlorophylls a and h, pheophytins a and h, lutein, and carotene in processed spinach. The method, developed primarily for calorimetric studies, involves extraction of the spinach with acetone and chromatographic separation on a sugar-starch (70:30) column. Equations were developed for spectrophotometric estimation of the amount of each pigment in the eluate from the column. The method gave recovery values of 95–98% for a wide range of pigment mixtures, and a coefficient of variation of approximately 1.5% for reproducibility on the same extract.Fresh spinach was blanched, pureed, packed in glass thermal-death-time tubes and processed in an oil bath at 240, 250, 260, 270, and 280°F for a process value equal to Fo 4.9. Color measurements indicated a difference of 4.1 units between the controls and the samples processed at 280°F, and 11.6 units between the controls and the samples processed at 240°F. The pigment changes indicated a progressively smaller change in chlorophylls a and h to pheophytins a and h as the processing temperature was raised. Chlorophyll a was degraded more rapidly than chlorophyll b, and the ratio of the two changed from 1.55 for the samples processed at 280°F, to 0.92 for the samples at 240°F. Some degradation of lutein was observed, particularly at the lower processing temperatures, whereas carotene was unchanged. The pigment-free tissues also showed more change in color at the lower temperatures, but the contribution of the pigment-free tissues and the degradation of lutein to the over-all color change was very small. The major reasons for the change in color of the spinach puree upon processing were, first, the degradation of chlorophyll a to pheophytin a, and second, the degradation of chlorophyll b to pheophytin b.

Notes: A polarographic method for measuring the molecular oxygen content of foods is described. Oxygen contents determined by the method were of the same order of magnitude as peroxide oxygen values of non-rancid fats and oils. Factors that controlled the molecular oxygen content of dehydrated foods were percent moisture, surface area, partial pressure of oxygen, and absorbability of other gases in the headspace.

Notes: Snap bean pectin methylesterase had a pH optimum of 8.2. Its activity was enhanced by the presence of salts such as sodium chloride and calcium chloride. Low pH conditions increased the susceptibility of the enzyme to heat inactivation. There were indications that conditions were present in the intact pod which protected the enzyme from heat denaturation. The enzyme had a Q10 of 1.4 over a wide temperature range. It was not regenerated on frozen storage.

Notes: A range of colors for spinach, carrots, and pears was produced by blending samples of different colors and diluting with water. The samples were examined by a visual panel under a MacBeth Examolite to determine the “just noticeable color difference” (JND) and were then measured with a Colormaster differential colorimeter and a Color-Eye calorimeter. The JND figures were 1–2.5 delta-E units calculated by the Adams chromatic value equation. Repeatability figures on the instruments above were respectively 1/2 and 1/4 of the JND values for spinach and pears. For carrots, the repeatability and JND figures were of the same order. Repeatability figures for 4 other calorimeters were lower or approximately equal to the JND figures, indicating that several of the calorimeters could be used to determine color differences as well as an average visual panel.

Notes: Peroxidase was regenerated in samples of peas that had been blanched just sufficiently to destroy the original peroxidase activity. The regeneration occurred after a few months in peas stored at −18° C, or within a few hours in thawed peas held at room temperature. The maximum activity regenerated was about 4% of the original activity. No regeneration occurred in peas given substantially more heat treatment than was needed for inactivation. Peroxidase regeneration during frozen storage, or after thawing, did not affect the quality of peas.

Notes: Ascorbic acid oxidation was studied in relation to the natural copper level and to lipid peroxidation in milks produced by cows receiving alfalfa bay or pasture. Correlations were highly significant (r = 0.79**) between ascorbic acid oxidation rate and natural copper for both alfalfa and pasture milks. The correlation between lipid peroxidation (by the TBA test) and ascorbic acid oxidation rate was very highly significant (r = 0.87***) in alfalfa milks but nonsignificant in pasture milks.Some postulated mechanisms for the action of copper and ascorbic acid in producing oxidized flavor were studied. The results do not support the theories of the role of the ascorbic acid radical, or of hydrogen peroxide, in the initiation of oxidized flavor.The kinetics of ascorbic acid oxidation by light, hydrogen peroxide, and ascorbic acid oxidase were examined. Zero-order kinetics was found for light, and first-order for the other agents.

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: A relationship between the degree of brownness produced by deep-fat frying or by evaporating to dryness in a 100°C electric oven was established. Fresh pork as chops, in a water slurry, or a water extract developed varying degrees of brownness on heating. The amount of brown color development was related to the level of reducing sugars in the tissues. The degree of color development could be measured spectrophotometrically at a wavelength of 375 mμ. The development of brownness in buffered solutions was pH-dependent, with maximum color being produced between pH 5.60 and 5.90.

Notes: The unique and complex mixtures of earotenoids in oranges present difficulties in analysis and interpretation of results. The situation is at times further complicated by the addition of β-carotene to orange juice. Existing analytical procedures, in combination, have been adapted to a rapid quantitative method for both total carotenoids and carotenes. The method involves extraction with a foaming solvent mixture, saponification of esterified oxygenated carotenoids, separation of carotenes by column chromatography, and measurement with a spectrophotometer. An increase in carotenes from the normal level of less than 10% of the total carotenoids to approximately 20% is readily detected, reflecting a sensitivity adequate to the interpretive needs in examining commercial products.

Notes: Fiein cannot hydrolyze native collagen. Collagen can he degraded by this enzyme only after it has been denatured by heat, low pH, or high salt concentrations. This appears to he true also for the action of bromelain, papain, and trypsin on collagen.

Notes: Some of the variables influencing the stability of purified and unpurified spinach catalase during storage were evaluated in model systems. A purified preparation of spinach catalase was obtained from spinach leaves by comminution and extraction with phosphate buffer and extraction with n-butanol, NH4)2SO4 precipitation, (NH4)2SO4 fractionation, dialysis, and lyophilization. The preparation had a Kat.-f. of 3300 at pH 7.0. The stability of the enzyme in storage was influenced primarily by storage temperature, the pH of catalase solutions, and the activity of microorganisms. The enzyme concentration had a relatively minor effect on catalase stability. The stability of spinach catalase during storage was not influenced by the presence of NaCl, sucrose, starch, and denatured catalase in catalase solutions; the atmospheric pressure under which solutions were stored: or differences in freezing rates.

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: 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: Thirty-four pairs of similar, commercially acceptable wines and a freshly prepared 50–50 blend of each pair were scored for quality by a small expert panel. The composite scores of the blends did not differ to even a low degree of significance from the score of the highest-scoring member of the pair. The scores of the blends were very highly significantly better than the scores for the low-scoring wines or the mean of the low- and high-scoring wine in each pair. In 7 cases among the 34 the blend's composite score was higher than that of the highest-scoring wine, and in no case was it lower than that of lowest-scoring wine of the pair. Increased complexity of flavor is believed to be a major factor in the favorable effect of blending shown in this study; other possible effects are discussed.

Notes: The nutritive value of INCAP Vegetable Mixture 9 in young and protein-depleted adult rats was studied. This mixture contains 28% lime-treated corn, 28% sorghum grain, 38% cottonseed flour, 3% kikuyu leaf meal, and 3% torula yeast. When Mixture 9, skim milk, casein, or meat flour was fed combined with different amounts of starch to give a range of dietary protein levels, the nutritive value of the vegetable mixture for rats compared favorably with that of animal proteins at the higher levels of protein intake. Both young growing rats and protein-depleted rats were used. The growth response was generally less to the vegetable mixture at low protein levels than when animal proteins were fed at the same dietary level, presumably because of a lysine deficiency also observed in previous chick trials.When the corn and sorghum combination was replaced in the mixture by processed corn, sorghum, rice, whole wheat, or oats, no significant changes were noted in the nutritive value. Furthermore, roasting, boiling, and lime-treating corn and sorghum did not affect the nutritive value of the mixture.

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: Variations in the distribution of water in bovine muscles were investigated with histological and chemical analyses. A histological method has been developed to measure the extracellular space. This property, along with water and protein content and pH values, was determined in four muscles from each of four animals. The results indicate that extracellular space varied among the muscles of the animals according to a definite pattern. Among the relations found, extracellular space was positively correlated with the water-protein ratio, whereas intracellular water content was negatively correlated. The evidence indicates that, in the muscles that characteristically contain a relatively high proportion of water to protein, the additional water is located in extracellular spaces.

Notes: The finding that iron has a profound effect in increasing both the rate and extent of Pseudomonas spoilage of experimentally infected shell eggs was extended to other egg spoilage bacteria. All bacteria tested were so affected. These gram-negative bacteria included five strains of Proteus, three of Paracolobactrum, two of Alcaligenes, two of Aerobacter, two of Achromobacter, and two of Salmonella.

Notes: Staphylococci are destroyed during the heat processing of both smoked and fully cooked hams. Although these organisms are capable of growth in the presence of sodium chloride, sodium nitrate, and sodium nitrite in the concentrations used in cored meats, they are readily destroyed in the presence, as well as the absence, of these agents at a temperature of 137° F. Twenty-two of 53 strains of Staphylococcus aureus were killed in excess of 99% after 10 min exposure at this temperature. Thirty-one strains exhibited more resistance, but were destroyed in excess of 99.9% after 60 min at 137°F. The significance of these results in terms of previous studies is discussed.

Notes: The protein, oil, ash, moisture, sodium, and potassium content of samples of butterfish, flounder, pollock, and hake was determined. In addition, length, weight, and fillet yield have been recorded. Fillet yield differed markedly both with species and with the size of the fish. Analysis showed a wide variation in the percentage of oil, not only in butterfish (considered an oily fish) but also in lean fish such as silver hake and flounder. Protein content proved to be consistently higher in pollock than in the other fish. Mineral and oil components showed a much higher percentage in offal than in corresponding fillets. Analysis of variance indicated that significant differences in results were related to the season in which the fish were caught.

Notes: A highly significant correlation (r =−0.97) exists between the amount of enzymatically developed pyruvic acid present in the juice of comminuted onion and the olfactory threshold concentration of the juice. The correlation indicates that determination of pyruvic acid in freshly prepared onion juice constitutes a fairly reliable, simple, and convenient method of estimating at least one aspect of onion flavor.

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.