Shear Press Values Research Articles

EFFECTS OF VARYING LEVELS OF SUCROSE, CORN SYRUP SOLIDS AND VINEGAR ON THE QUALITY OF SWEET PICKLED PEACHES

ABSTRACTQuality changes in pickled peaches packed in three syrup concentrations and five ratios of sucrose‐corn syrup solids were studied. Variations in the ratios of sucrose and corn syrup solids (CSS) had no apparent effect on Brix level or pH of the syrup. Shear press values which denoted increased firmness associated with osmotic action which caused shrinkage and loss of drained weight. The more attractive color of peaches packed in high density syrups (66–69° Brix) and all sucrose syrups was related to higher Gardner “a’ values. Different ratios of sucrose to CSS in the syrups significantly affected the sensory ratings for appearance, color, aroma, texture and flavor. Sensory quality scores decreased significantly when CSS were used to replace 50% or more of the sucrose in packing syrups. Multiple‐comparison sensory difference tests closely paralleled findings from sensory quality ratings. Significant differences existed in sweetness, fruit flavor and general quality but not acidity. It was evident that sourness ratings were influenced by variations in syrup acidity. The Brix and acid levels of pickled peaches could be decreased by approximately 20% without causing significant changes in general quality and fruit flavor.

EFFECTS OF POST‐HARVEST STORAGE ON THE QUALITY OF CANNED SNAP BEANS

ABSTRACTA study was conducted to simulate conditions that exist in loaded trailers and bulk bins during transport and storage of snap beans to study the effects of post‐harvest storage on quality of canned snap beans. Post‐harvest variables were 2 air flow rates, 3 storage times, 4 storage temperatures and 2 methods of blanch. Respiration rates were higher in beans that were held under high temperatures and a fast flow rate. Sensory ratings for color and general appearance were higher on beans stored under a slow flow rate. Beans stored under a fast flow rate were higher in % seed, fiber, hemicellulose and cellulose. Browning was more severe in beans stored at a fast flow rate. As storage times and temperatures were increased, beans decreased in greenness (‘‐a’) and sensory scores. Shear press values, % seed, fiber, total sugar and cellulose increased in the canned beans as storage times and temperatures were increased. The beans that were blanched in rotary steam were lighter in color and less firm than those blanched in water.

EFFECT OF FAT LEVEL AND RADAPPERTIZATION DOSE LEVEL ON THE QUALITY OF PORK ROLLS

ABSTRACTThe effects of radiation processing on pork rolls with 0.75% salt and 0.3% sodium tripolyphosphate added were studied. Pork rolls were prepared with three fat levels (10, 15 and 20%) and irradiation processed at doses of 30, 45 and 60 kJ/kg, ‐30°× 10°C irradiation temperature. Differences in the sensory quality, consumer preference and shear press values were determined. No significant differences were determined among the ratings for the sensory characteristics or preference, although irradiation at 60 kJ/kg tended to lower product quality and preference ratings. Shear press values decreased with increasing fat levels. No decrease in shear press values was found among samples irradiated at 30, 45 and 60 kJ/kg.

FLAVOR AND TEXTURAL CHANGES IN RADAPPERTIZED CHICKEN AS AFFECTED BY IRRADIATION TEMPERATURE, NaCl AND PHOSPHATE ADDITIONS

ABSTRACTThe effects of food‐grade phosphates; sodium tripolyphosphate (TPP), tetrasodium pyrophosphate (PP), a mixture of tripoiyphosphate and hexametaphosphate (HMP), and sodium chloride additions (0.05, 1.0 and 1.5%) in irradiated boneless chicken rolls were studied. Temperatures during irradiation processing were 0°C, −30°C and −80°C, and all samples received a 45–56 kJ/kg dose. Samples were evaluated for sensory characteristics and preference by technological or consumer type panels. Textural differences were determined using a Kramer Shear Press. Reflectance values at 640 nm were obtained using a reflectometer. The sensory characteristics and preference of the chicken rolls were significantly affected by temperature during irradiation. Samples irradiated at 0°C were rated lower in preference and had higher intensities for off‐odor and irradiation flavor. No significant differences were found between samples irradiated in a range of −30°C to −80°C. Shear press values increased and reflectance values decreased with the lowering of the irradiation temperatures. The addition of a small amount of salt with 0.5% tripolyphosphate significantly improved the preference ratings of irradiated chicken rolls. No differences in the sensory characteristics were found between roll samples with 0.5% additions of TPP, PP, or a TPP and HMP combination. Shear press values were significantly affected by the addition of NaCl and TPP in both irradiated and nonirradiated samples.

VARIABLES AFFECTING THE ACCEPTABILITY OF RADAPPERTIZED GROUND BEEF PRODUCTS

ABSTRACTA series of experiments were conducted to determine the effect of different variables on the quality of an irradiated ground beef product. Factors studied included: different food‐grade phosphates; NaCl content; fat content; and size of grind. The influence of these variables on the cooking loss (moisture retention), shear press values and sensory scores was studied. The addition of phosphates and NaCl was desirable in controlling cooking losses. The most effective phosphate was tetra‐sodium pyrophosphate. The addition of NaCl decreased the shear press force required to penetrate the beef patty, i.e., it tenderized the product. Phosphate addition did not affect the shear press force. Increased fat content increased the cooking losses, but did not affect the shear press force. Irradiation with sterilizing doses had a marked effect on decreasing the shear press force.

Relationship of Processing Methodology to Quality Attributes and Nutritional Value of Canned Spinach1

Abstract The volume of water utilized for washing did not affect either quality attributes or nutritional value of canned spinach (Spinacia oleracea L.). Dipping in a detergent solution prior to the washing decreased greenness, optical density of liquor, nitrates and ascorbic acid. The amount of grit and sand was not influenced by either detergent or volume of water used for washing. Shearpress values of canned spinach blanched in either steam or water did not differ. Color was rated slightly higher on spinach that was blanched in steam. Water blanching leached out more nitrates, riboflavin and ascorbic acid than steam blanching, but carotene was not affected.

Pre- and Postharvest Factors Affecting Textural Quality of Fresh Asparagus1

Abstract Factors determined to have a pronounced effect on shear-press peak-force values of asparagus, Asparagus officinalis L. included sample size, spear diameter, length of green, and preharvest temperature. Shear-press values were greater following periods of cold weather in early spring. Larger diameter spears had lower peak-force values than smaller spears, indicating that larger spears are more tender than smaller spears. The number and diameter of spears produced by a particular cultivar, and not differences between cultivars, were the characteristics observed to influence shear-press values. Shear-press max peak-force values correlated well with subjective and objective determinations of asparagus fiber.

TEXTURAL QUALITY PREDICTION OF REHEATED FROZEN FRENCH FRIED POTATOES BY OBJECTIVE TESTING OF RAW STOCK

ABSTRACTResearch is described which evaluates and relates a simple Durometer test of raw potato lots with instrumental texture measurements and sensory panel evaluation of oven‐reheated frozen French fried potatoes. Statistical evaluation of the mean data shows no difference between the Idaho and Maine Russet Burbank samples for any of the measurements. Durometer means were significantly correlated with shear press measurements and all shear press values were significantly intercorrelated. The large correlation coefficients between Durometer readings and other measurements indicate that Durometer evaluations can be used to predict from the raw tubers the shear press measurements and overall moistness, crust crispness and internal mealiness of oven‐reheated frozen French fried potatoes. Further work is necessary with other source and variety combinations before a general prediction statement can be made.

Sensory and Microbiological Evaluation of Smoked Cornish Game Hens

Two trials were conducted to determine the organoleptic characteristics, shear press values, and color of oven-roasted and smoked Cornish game hens. A group of panelists evaluated bite-sized pieces of light and dark meat from oven-roasted and smoked birds for flavor, tenderness, juiciness and overall preference. The panelists preferred the smoked product over the oven-roasted product 5:1. Both light and dark smoked meat were found to have a more desirable flavor and to be more tender and less juicy than the oven-roasted meat. Shear values for the smoked product were significantly lower than those obtained from oven-roasted samples. The interior and exterior surfaces of the pectoralis major from smoked and oven-roasted birds were evaluated for dominant wavelength, excitation purity and luminosity on an IDL COLOR-EYE reflectance colorimeter. The exterior and interior surfaces of the pectoralis major from smoked birds were darker than meat from oven-roasted birds. Total aerobes were effectively reduced to <10 organisms/ml. of rinse solution, following smoking of the birds. Coliforms were not recovered from smoked birds immediately after the smoking process nor after three weeks frozen storage.

Influence of Thawing and Cooking Procedures on Selected Characteristics of Broilers

Fresh broilers purchased from a local supermarket were halved, frozen at −29°C., and held in the freezer for 6 weeks. Broiler halves were cooked either from the frozen state or after they had been thawed 48 hours at 4°C. They were deep-fat fried, cooked by microwave, pan fried, or oven roasted.Weight losses were significantly greater for meat thawed before cooking than for that cooked from the frozen state. Microwave cooking and oven roasting resulted in lower weight loss than did deep-fat or pan frying. Taste panel members could not distinguish between broilers cooked from the frozen state and broilers thawed before cooking. Shear press values did not differ significantly as a result of preparation or cooking method.Total heme pigment in flesh surrounding the femur of cooked broilers was determined. No significant difference was found between meat thawed and that nonthawed before cooking or among cooking methods. Parts cooked from the frozen state had less bone darkening than did the parts cooked after thawing. Deep-fat frying and microwave cooking resulted in severer bone darkening than did the other cooking methods.

Comparison Between Shear Values and Taste Panel Scores for Predicting Tenderness of Broilers

Eight week old broilers were used in an experiment to correlate taste panel scores with shear press values for predicting tenderness. The slaughtered birds were divided into four groups and processed by methods known to produce varying degrees of tenderness. These methods were: dry picked (control) scalded for 5 minutes at 60° C., beaten with a wooden paddle for 5 minutes after picking, and scalded for 5 minutes at 60° C. followed by beating for 5 minutes. After evisceration, all carcasses were aged 18 hours in an ice water bath. After aging the carcasses were cut-up and the breast of each bird was split in half. The split breasts and thighs from each bird were cooked in an autoclave at 101° C. for 20 minutes. The iliotibialis muscle of the thigh and two 3 mm. slices per half from the pectoralis major were removed. Shear values using an Allo-Kramer shear press and taste panel scores for tenderness were determined. Taste panel scores ranged from one (tough) to five (very tender). The thigh was not evaluated by the panel, but shear values were determined.Negative correlations of 0.71 and 0.76 for the first and second slice of the pectoralis major, respectively, were obtained from shear values and taste panel scores. Regression equations showed that shear press values above 8 kg. of force per g. of sample would be considered slightly tough to tough by the taste panel at the 95% confidence level.

Effect of Freezing Temperature on Tenderness of Light and Dark Broiler Meat

This study was undertaken to help clarify the role of freezer temperature on acceptability of fryers. Fresh breasts and drumsticks were tray-wrapped in polyethylene and frozen at 8° F. (−13.3° C.) until the end of the trial, −20° F. (−28.9° C.) in a blast freezer overnight, or −197° F. (−127° C.) in a liquid nitrogen freezer for 10 minutes. After freezing, the pieces were wrapped and stored at 8° F. for 6 to 8 weeks before testing. The meat was then defrosted, battered and deepfat fried for evaluation.Judging by shear press values, the fresh (unfrozen) meat and the meat frozen at 8° F. were significantly tougher than the pieces frozen at −20° F. or −197° F.

Acceptability of Frankfurters Made from Chicken, Rabbit, Beef, and Pork

Traditionally frankfurters are made from beef, pork and veal. Other meat animals, however, such as chicken and rabbit are excellent sources of protein and should make acceptable products. But in order to evaluate their acceptability in relation to those made from red meats, as much as possible of the psychological bias against frankfurters made from other meats should be removed. This project was undertaken to evaluate frankfurters made from chicken, rabbit, beef and pork when the panelists did not know the meat source and when red lighting was used to lessen color differences.Frankfurters were formulated from each of the four kinds of mean and from 50/50 combinations of each with chicken. They were evaluated by 13–14 trained judges, who rated them for tenderness, juiciness and overall acceptability. Shear press values and heating loss were also determined.Taste panel scores showed that, under the processing conditions used in this study, chicken alone and in combination with rabbit, produced frankfurters that were less firm, more juicy, better flavored and more preferred than beef alone. Heating loss and shear values were lower for chicken frankfurters.

Prebrowned Fried Chicken: 1. Evaluation of Cooking Methods

Chicken for a prebrowned fried chicken product was soaked in phosphate (Kena) and/or salt for 16 hours, then fried, to evaluate the effect of marination solutions. This was followed by an evaluation of eight cooking methods. These methods included precooking by: steaming, simmering, boiling, all followed by breading, battering and breading then frying to brown; and breading, battering and breading followed by deep fat frying to doneness. Also included were four methods involving steaming after breading and/or battering and breading. The methods were evaluated by taste paneling for tenderness, juiciness, flavor and overall acceptability. Shear press values, total moisture and yields were determined.Marination in 1–3% Kena improved flavor and yield, reduced shear values and increased total moisture when compared to the unsoaked control. Adding salt with the Kena improved flavor as well, after four days of refrigerated storage.Evaluation of the cooking methods indicated that simmering was slightly the best of the precook methods. The most desirable product, on the basis of shear values, total moisture and yields, was made by breading, battering, and breading, frying 20 seconds, steaming until done, then refrying 20 seconds.Taste panel scores showed no significant differences among the methods used, when the crust was removed before evaluation to avoid bias due to differences in seasonings.

STORAGE STABILITY OF COMMERCIALLY PREPARED AND FROZEN POND‐RAISED CHANNEL CATFISH (Ictalurus punctauts, rafinisque)

SUMMARY –The storage stability of frozen pond‐raised channel catfish from five commercial processing plants was examined. Three distinct types of processing treatment were included in the five lots. Fish samples were evaluated initially and at regular intervals during frozen storage up to 270 days. The evaluations included changes in moisture, pH, fat stability (TBA value) and shear press values of the uncooked fish, and in sensory ratings for appearance, aroma, color, texture and flavor of the cooked products. Moisture losses and changes in pH during frozen storage were not statistically significant (P = 0.05). Thiobarbituric acid (TBA) values indicative of changes in fat stability, incresed in all five lots of fish with prolonged storage but were not closely correlated with changes in flavor rating. Sensory ratings for quality of the cooked product decreased significantly with successive storage periods. The regression patterns representing changes in quality during storage varied among the different losts of fish. Certain variations were related to the processing treatments.

Yield of Snap Beans (Phaseolus vulgaris L.) as Influenced by 5-Chloro, 2-Thenyl, Tri-n-Butyl-Phosphoniumchloride1

Abstract A single foliar spray of 25 or 28 ppm 5-chloro,2-thenyl, tri-n-butyl-phosphoniumchloride (CTBP) when the first flowers opened increased yields of 2 cultivars planted in late summer and 2 of 4 cultivars planted in late spring, 1970. Yield increases were due to more pods. In general, CTBP treatments that increased yields did not influence seed and fiber development, shear press values, and color of 4-sieve and 5-sieve pods that were canned. Also, Ca, Mg, P, and K levels of 4-sieve, deseeded 5-sieve, and seeds from 5-sieve pods were not influenced by CTBP treatments.

HISTOLOGICAL AND PHYSICAL CHANGES IN CARROTS AS AFFECTED BY BLANCHING, COOKING, FREEZING, FREEZE DRYING AND COMPRESSION

SUMMARY— The effect of processing variables on the cell structure and physical characteristics of carrots were determined. The phloem portion of fresh carrots was subjected to one of the following treatments: blanching; cooking for 10 min; freezing at 0°F, −30°F or −320°F; freeze drying, compressing after freeze drying at approximately 1500 psi. Carrots at each treatment were tested for: (1) texture by means of the Ailo‐Kramer Shear Press; (2) water holding capacity by centrifuging at 500, 1000, 1500, 2000 and 2500 rpm; (3) histological changes by microscope observation of the tissue structure. Results indicate that among all treatments, freezing temperature is the most critical factor affecting the cell structure of the carrots. Freezing at 0°F or −30°F results in considerable disruption of the cellular structure, whereas it was minimal at −320°F. Carrots frozen at −320°F showed firmer texture as well as higher water holding capacity than the rest. Significant correlation coefficient was established between the shear press values and percent weight loss measured by centrifugation. This suggests that the latter may be used as an objective test for measuring textural changes in processed carrots and perhaps other foods.

The Effect of Freezing and Reheating on Shear Press Values of Precooked Chicken

INTRODUCTIONPrecooked frozen meat is increasing in popularity because of greater convenience. However, Watts et al. (1948), West et al. (1959), and Mitchell (1963) have reported that precooking reduces palatability of frozen meat.Mickelberry and Stadelman (1960Mickelberry and Stadelman (1962) compared the following cooking methods: micro-wave, deep-fat fry, deepfat fry and micro-wave, rotary-reel oven, and steam and deep-fat fry. They found that cooking chicken before freezing made it significantly less tender. Deep-fat fried birds were less tender than birds cooked by other methods.Stadelman and Wise (1961) reported shear values of breast meat increased (indicating less tenderness) by cooking before freezing. Miller and May (1965) reported that rate of freezing (0°, —30° and — 90°F.) did not significantly influence tenderness. They also reported that cooking chicken breasts before freezing and storing resulted in greater shear-press values than when the breasts were cooked after frozen storage.The present study was to evaluate methods of…

Seed Percentage, Seed Length and Shear Press Values in the Evaluation of Quality and Maturity in French Beans

SummaryIn experiments during 1967 and 1968 three French bean cultivars, Processor, Meteor and Tenderlong, were harvested twice-weekly as the crop matured. Field and laboratory tests, viz. alcohol-insoluble-solids (AIS), dry matter (DM), seed percentage, seed length and shear press values, were assessed as indices of maturity.Seed percentage and seed length increased with successive harvests but proved subject to variation with cultivar and with season. Shear values obtained using 100-g samples did not increase significantly with successive harvests. Both AIS and DM were good indices of maturity and were highly correlated (r > 0.99) with each other in both seasons.

Cooking quality of some Dutch potato varieties

The relationships among three methods for evaluating texture (sloughing during cooking, hardness of cooked potato dice and shear press value of French fries) and some chemical constituents (Ca, Mg, K, free pectin, phytin and citrate) were investigated, using the main specific gravity classes of seven Dutch potato varieties. The interplay of these constitutents (except K) in the softening of the texture during cooking was expressed as follows: Open image in new window