摘要:

ABSTRACTpH of ground beef components, from three purveyors, was measured for 150 consecutive days of production. Patties were produced from the components with pH values within the interval 5.6–6.2 and cooked (71°C) on a gas grill (176°C). The internal color of the cooked patties was described by a sensory panel. The internal color varied from grey in patties within the normal pH range (5.3–5.7) of muscle, to slightly red in muscles with a pH of 6.2. Red to pink cooked color was most intense inside those patties with the highest pH and the greatest concentration of total pigments. Bull meat exhibited a much higher pH and a greater level of total pigments than the other components studied. Controlling the pH of bull meat could be important in improving the cooking characteristics and quality of ground patties containing it. Purveyor specifications for bull meat should include pH as a criteria for purchase when cooking time and quality are critical to the cus

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08552.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTThe palatability and storage characteristics of fresh, frozen and precooked beef chuck roasts prepared using added phosphate‐salt and vacuum cooking bags were evaluated. Palatability attributes (tenderness, juiciness, beef flavor intensity, and off‐flavor intensity) of precooked roasts prepared in vacuum cooking bags with phosphate‐salt were as good or better than freshly cooked roasts. Precooked roasts in vacuum cooking bags had the lowest total bacterial counts after storage for 14 and 28 days. A palatable precooked roast beef product was developed that can be stored for 28 days a

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08553.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTFresh rib eye steaks were immersed in aqueous solutions of three binary systems consisting of oxychloro species and diluted acid activators, which, when mixed, generated a chlorous acid/chlorine dioxide system. Lipid oxidation, color, pH and weight changes as well as microbiological keeping quality of vacuum‐packaged steaks were examined during 8 weeks storage at 2°‐4°C. Two of the three binary systems tested reduced psychrotrophic, anaerobic and facultative anaerobic and lactic acid bacterial growth and strongly inhibitedEnterobacteriaceaein the steaks but also had adverse effects on beef color and lipid oxid

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08554.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTConflicting claims of the effects of early postmortem electrical stimulation on the temperature and cooling rate of beef were investigated, using an improved method of temperature measurement and a precise alternation of sides receiving the treatment. No stimulation effect on temperature was detected, but a consistent laterality effect was observed, the right loin on average being almost 2°C warmer than the left at 3 hr postmortem regardless of prior unilateral or bilateral stimulation. This temperature difference appears to be a localized phenomenon due to the asymmetric distribution and “tightness” of the kidney fat overlying the interior surface of the central loin

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08555.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTConventionally trimmed (0.6 cm) and completely trimmed (0 cm) prok chops were used to evaluate the effect of removing subcutaneous fat on lipid retention during broiling of pork. Composition of the lean portion of cooked chops was not affected by removal of external fat before cooking. Conventional chops contained 4.4% either extractable lipid and completely trimed chops contained 4.3%. Lipid retention was also the same at 94–99%. Recovery of moisture, protein, and lipid was 98–99%, using ether extraction or chloroform:methanol extraction. Therefore, the concept of lipid migration during cooking was not a tenable explanation for reports of lipid retention exceeding 100% during broiling of pork chops typical of those available to consum

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08556.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTThe effects of selected organic acids and salts on microbial numbers, pH, exudate, and color were studied for vacuum‐packaged, fresh pork chops. Pork chops were dipped for 2 min in (v/v) 1% acetic acid, 1% acetic/1% lactic acid, 1.5% acetic/1.5% sodium acetate, 3% acetic/3% sodium ascorbate, 3% acetic/2% NaCl or sterile, distilled water before being vacuum‐packaged and stored at 2°– 4°C for 6 weeks. Treatments containing 3% acetic acid resulted in lower aerobic microbial numbers (P<0.05) and effectively inhibitedEnterobacteriaceae.Treatments containing 1% acetic acid, with or without 1% lactic acid, were ineffective. All acid treatments increased exudate and were detrimental to meat color (P<0.05) although sodium ascorbate reduced color damage. Chops treated with 3% acetic acid/3% sodium ascorbate had the highest Hunter a and L color

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08557.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTThe protein adsorption rate from whole milk onto various surfaces was modeled as a function of contact surface tension, surface temperature, and time. A new kinetic parameter related to the value of contact surface tension which corresponds to a minimal interaction between food components and the solid surface is introduced. This experimentally measurable parameter quantifies the influence of contact surface tension on the activation energy required for irreversible protein adsorption. In spite of its simplicity, the model adequately predicted initial adsorptive behavior under steady flow conditions for a wide range of surface properties.

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08558.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTThe effect of pretreatment upon the composition and physicochemical and functional properties of whey, ultrafiltration (UF) retentate and freeze‐dried and spray‐dried whey protein concentrates (WPC) was investigated. Pretreatment was by cooling cheese whey to 0‐5°C, adding calcium chloride, adjusting to pH 7.3, warming to 50°C, and removing the insoluble precipitate that formed by centrifugation or decantation. UF permeation flux rate of pretreated whey was about double that for control whey. Pretreated whey was essentially turbidity free, contained 85% less milkfat, 37% more calcium and 40% less phosphorus than whey. Pretreated whey WPC proteins were slightly more soluble at pH 3, but less functional for emulsification than whey WPC proteins. Neither whey WPC proteins nor pretreated whey WPC proteins was functional for foaming at 6% protein concen

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08559.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTGoat's milk was heat‐processed under different time‐temperature conditions of pasteurization and sterilization. Losses of thiamin, riboflavin, and total vitamin C in HTST, Flash, and UHT were less than that by LTLT and Autoclave. Also residual oxygen in the milk affected the loss of total vitamin C during storage. A longer shelf‐life of pasteurized milk was obtained with HTST, HTST overpasteurization, and Flash process; however, there was no significant difference between UHT and Autoclave sterilized products. From the above results, HTST pasteurization was considered the best process to preserve milk qu

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08560.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTEffects of pasteurization and frozen storage on the rheological behavior of liquid whole egg (LWE) were studied using a cone and plate viscometer. Homogenized LWE control and LWE heated at 60°C, 64°C or 68°C for 3.5 min were evaluated during 80 days storage at −24°C. Thixotropic behavior was observed in all frozen samples. Apparent viscosity increased with pasteurization and frozen storage. Unpasteurized LWE exhibited Newtonian behavior throughout storage. Pasteurized LWE flow properties changed from Newtonian to Bingham Plastic during storage. Identification of rheological parameters will help understand the molecular changes that occur during the processing and storage of LWE and help processors monitor LWE qu

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1989.tb08561.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY