COMPARATIVE STUDY OF SHELF-LIFE OF FRANKFURTERS CONTAINING PLANT PROTEIN ADDITIVES1

Soy flour (SF), soy concentrate (SC), soy isolate (SI) and corn germ protein flour (CGPF) were incorporated in frankfurters. The sensory analysis, chemical, and microbiological tests were conducted to investigate the effect of plant proteins on stability during vacuum-packaged storage. No significant difference in meaty aroma was found between all samples after 45 days storage. Atypical flavor and aroma of all samples, including the all-meat control increased (P < 0.05) after 45 days storage. A tendency was found of increase in atypical aroma and flavor with increase in total volatile nitrogen values and total psychrophiles during storage. Salty flavor increased with storage time in experimental samples, but juiciness decreased. Samples containing SF and SC had higher total volatile nitrogen than SI and CGPF containing samples at 2, 30 and 45 days of storage. No significant differences were found in TBA values between tested samples, except higher TBA values for SI containing samples. There was no significant difference among samples in total psychrophilic counts.     

EFFECT OF CARRAGEENAN ON PROCESSING AND QUALITY CHARACTERISTICS OF LOW-FAT FRANKFURTERS

Three types of carrageenan (K, I, K+I) × 4 levels (0, 0.25, 0.5 and 1.0%) were evaluated with a complete factorial design to characterize the effect of carrageenans on processing and quality characteristics of low-fat frankfurters (9% fat, 13% protein). l-Carrageenan at 0.5–1.0% level appeared to be more beneficial for the production of low-fat frankfurters. It reduced (P<0.05) the hardness of the skin and contributed to a softer (P<0.05) product and higher overall acceptability. Low-fat frankfurters (9% fat) manufactured with I-carrageenan (IC) or in combination with finely ground toasted bread (TB), isolated soy protein (ISP) and pork skin (PSK), were compared to high-fat (27% fat, 11% protein) and to low-fat (9% fat, 13% protein) control frankfurters prepared with 3.5% potato starch (PS), as well as with commercial frankfurters (25% fat, 11.6% protein, 4.5% starch). Frankfurters with IC had higher (P<0.05) moisture, softer (P<0.05) skin and the highest (P<0.05) separation of gelatin. However, textural properties and overall acceptability were similar (P>0.05) to commercial and high-fat control frankfurters. Addition of TB had no significant effect. Use of ISP and PSK improved (P<0.05) the water-binding capacity but negatively affected the overall acceptability of frankfurters.     

QUALITY CHARACTERISTICS OF MEAT BATTERS AND FRANKFURTERS CONTAINING WHEAT GERM PROTEIN FLOUR1

Frankfurters were extended with wheat germ protein flour (WGPF) at 3.5, 5.0. and 7.0%. Water added during formulation was increased by 2% for every 1% of WGPF added. Batters containing WGPF had higher pH and adhesiveness values. Viscosities of the batters were not affected by addition of WGPF. Batters containing WGPF had lower cooking losses, and lower percent water and fat separated. Positive effects, such as lower cooking losses, higher processing yields and lower percent fat, were not consistent at levels of WGPF beyond 3.5%, probably because of higher levels of added water. Total yields of the samples containing WGPF were higher than those of control samples. No differences were observed in protein and amino acid contents of samples. Lower fat content was found in samples extended with 7.0% WGPF. Frankfurters containing WGPF had lower shear force and firmness values. Differences in color of frankfurters were also observed.     

QUALITY CHARACTERISTICS OF TURKEY BOLOGNA FORMULATED WITH CARRAGEENAN, STARCH, MILK AND SOY PROTEIN

A low-fat (12%) high-added water (27%) bologna was formulated with mechanically deboned turkey meat (MDTM) and either carrageenan (0.5%), milk protein (2%), isolated soy protein (2%), or starch (2%). Cooking loss, purge loss during storage, cooked product bind, sensory characteristics, and batter viscosity were evaluated. Starch added late in the chopping process was the most effective in reducing cooking loss as well as decreasing (P < 0.05) purge loss during storage (both refrigerated and frozen storage). Cooked product hardness was increased (P < 0.05) by all test ingredients, except starch and kappa carrageenan added late in the chopping process. Kappa carrageenan incorporated before chopping significantly (P < 0.05) increased cooked product bind. Overall acceptability (sensory analysis) scores were higher (P < 0.05) when milk protein, isolated soy protein and starch were added during chopping, compared to their addition prior to chopping. However, this order of addition effect was not observed for either of the carrageenan treatments.     

EFFECTIVENESS OF SELECTED ADJUNCTS ON PROCESSING AND SENSORY CHARACTERISTICS OF EXTRA LEAN FRANKFURTERS

The effects of maximum levels of selected additives in extra lean frankfurters (<3% fat) were studied. Seven treatments, with four replications each, were evaluated at three time periods (0, 30 and 60 days) in a randomized complete block design. The treatments consisted of: control; kappa-carrageenan; hydroxypropyl methylcellulose (HPMC); high methoxy pectin (pectin); an acid modified food starch; sodium lactate; and acid enzyme deheated mustard. All treatment frankfurters had higher (P<0.05) yields than the controls. The pectin product had an unacceptable extremely soft, smooth pasty texture. Pectin and HPMC products had the lowest (P<0.05) purge at 60 days. In general, the addition of some appropriate additive or additives to low-fat sausage products appears to be appropriate to increase processing yields, reduce cost and help bind free water so long as the additive or additives do not adversely affect other properties of the product.     

QUALITY CHARACTERISTICS OF LOW-FAT FRANKFURTERS MANUFACTURED WITH POTATO STARCH, FINELY GROUND TOASTED BREAD AND RICE BRAN

Low-fat frankfurters (10% fat, 13% protein) were produced with 3.0% potato starch, finely ground toasted bread and rice bran or their combination. No differences (P > 0.05) were found in processing yield and purge accumulation among treatments of tested ingredients. Potato starch (3.0%) significantly increased the lightness, hardness and skin strength of low-fat frankfurters. Finely ground toasted bread had the highest scores for visual color, external redness, flavor intensity and overall acceptability and improved (P < 0.05) skin strength of frankfurters in comparison to potato starch. Low-fat frankfurters with 3.0% rice bran had the same (P>0.05) visual color scores, redness and textural properties as those produced with potato starch and toasted bread, but lower (P < 0.05) flavor intensity and overall acceptability and were judged as "just acceptable". Decreasing the rice bran from 3.0 to 1.5% and using it in combination with toasted bread (0.75%) and potato starch (0.75%) had an insignificant effect on the flavor intensity and overall acceptability of low-fat frankfurters.     

NUTRIENT QUALITY OF SELECTED VEGETABLES PREPARED BY CONVENTIONAL AND COOK-FREEZE METHODS

Selected vegetables (spinach, broccoli, sweet potatoes, and collard greens) prepared in 2.27 kg (5 lb) quantities by boiling, were frozen and stored for six months at ?18°C. Zinc, iron, β-carotene, and ascorbic acid were determined on the raw vegetable immediately after cooking and after reheating in a microwave oven subsequent to 6 months frozen storage. The greatest nutrient loss occurred for water soluble nutrients during boiling. Nutrient comparison between cooked samples (conventional method) and samples microwaved after 6 months frozen storage (cook-freeze method) indicated that differences existed only in ascorbic acid content of spinach. Data indicated that vegetables prepared by cook-freeze, a method used by health care institutions, were generally equal in nutrient quality to conventionally prepared vegetables.     

MEASURING CHARACTERISTICS OF FRANKFURTERS EXTENDED WITH SORGHUM FLOUR1

Inclusion of 2, 3.5 or 5% sorghum flour in frankfurters had no significant influence on pH, viscosity or thermal stability of batters. Water‐holding capacity was lower for batter containing 5% sorghum flour. The level of sorghum flour had no effect on proximate composition, mechanical, sensory or shelf‐life measurements. Leucine and isoleucine levels and saturation index decreased with the incorporation of 5% sorghum flour. Storage period at 6/pm 1C also had no effect on sensory measures of frankfurters. However, water activity and TBA values of frankfurters increased after 15 days of storage; no further increases were found after 30 days. Microbial colony forming units could be detected only after 30 days and did not increase further. Total volatile nitrogen did not increase until day 40 of storage. No interactions were found between level of sorghum flour and day of storage for any of the parameters tested. Up to 5% sorghum flour can be used in frankfurters without adverse effects.     

CHARACTERISTICS OF FRANKFURTERS WITH DIFFERENT COOKING PARAMETERS

The purpose of this study was to evaluate the effects of different reheating methods (steeping, broiling, or microwaving) and end-point reheating temperatures (66C, 77C, or 88C) on the physical and sensory characteristics of frankfurters. Instron hardness, shear force, sensory hardness, and saltiness scores increased and juiciness scores decreased with additional reheating temperature when frankfurters were microwaved or broiled. Frankfurter density decreased with higher ultimate temperature which was attributed to additional gas volume. Expressible moisture increased with a higher ultimate temperature when frankfurters were steeped. Free water was the highest at 77C. Neither cooking procedure nor ultimate temperature influenced protein denaturation as determined by gel electrophoresis and enzymatic digestion.     

EFFECT OF ADDITIVES ON RHEOLOGICAL CHARACTERISTICS AND QUALITY OF WHEAT FLOUR PAROTTA

Effects of oxidizing agents (potassium bromate [20 and 40 ppm], ascorbic acid [100 and 200 ppm] and potassium iodate [20 and 40 ppm]), reducing agents (potassium metabisulphite [100 and 200 ppm] and cysteine hydrochloride [50 and 100 ppm]), enzymes (fungalα‐amylase [10 and 20 ppm] and protease [10 and 20 ppm]) and dry gluten powder (1, 2 and 3%) on rheological characteristics of dough and quality of parotta were studied. Addition of oxidizing agents and dry glutenincreased values for farinograph stability, extensograph and mixograph areas, apparent biaxial extensional viscosity, compressive stress, hardness and cohesiveness, while reducing agents and enzymes decreased the aforementioned characteristics and increased force decay parameter and adhesiveness of the dough. Among the different additives studied, incorporation of 100‐ppm potassium metabisulphite, 50‐ppm cysteine hydrochloride and 10‐ppm protease increased the overall quality score of parotta.     

QUALITY AND SAFETY CHARACTERISTICS OF MILK SOLD IN THE STATE OF KUWAIT

ABSTRACT

The food chain operational links for locally produced and imported milk were prepared. Quality and safety assessment of milk were also carried out by collecting raw milk samples from the farms, and pasteurized milk from retail and wholesale outlets. Milk samples were analyzed for pH, titratable acidity, clot on boiling, aflatoxin M1, antibiotic residues, and microbiological quality and safety. Results have shown that the mean pH and acidity of raw milk were 6.83 and 0.180%, while the mean pH and acidity values for local and imported pasteurized milk were 6.9 and 0.170%, and 6.8 and 0.150%, respectively. Furthermore, all raw and pasteurized milk samples were negative for the clot on boiling test and were within the allowable limits for aflatoxin M1 and antibiotic residues. However, raw milk samples collected from the local dairy farms were unacceptable because of the high somatic cell count and high Staphylococcus aureus counts.

PRACTICAL APPLICATIONS

Securing an adequate food supply for the nation has always been the fundamental concern of Kuwait's policy makers. Under local Kuwaiti conditions, with high temperatures over most of the year and the high level of imported products with unknown histories, combined with handling by unskilled labors, food losses can be excessive. This situation creates marketing problems for some of the highly perishable foods like milk. The baseline data of milk losses obtained during this study would help to bring about improvements in storage, handling and distribution practices and develop recommendations for private/public agencies to adopt technologies for improving milk losses. Furthermore, since there are no accurate statistics on milk losses in Kuwait, these primary data could be used to determine the economic values of milk losses in Kuwait.

     

PHYSICAL AND SENSORY CHARACTERISTICS OF COMMERCIALLY AVAILABLE FRANKFURTERS

This study's objective was to identify the range of physical and sensory properties of commercially available frankfurters. Twenty-five types of frankfurters were evaluated by a six-member sensory panel and subjected to Instron texture profiling. A wide range of sensory and textural characteristics was observed for acceptable frankfurters. Salty flavor and juiciness were correlated with fat content, but salt and fat content were inversely correlated. Negative correlations occurred between fat content and Instron fracturability and compression; fat content decreased resistance to force from mechanical stress. Firmness was positively correlated with Warner-Bratzler shear force. The development of an accurate regression equation to predict sensory hardness was not possible with this data set.     

DIETARY MANIPULATION OF THE COMPOSITION AND QUALITY OF MILK AND MILK PRODUCTS

The role of milk and milk products in the human diet is examined briefly and the possibility discussed of expanding the market for dairy products through the production by natural methods of materials with distinctive characteristics. The scope for modifying milk composition by genetic or physiological means is considered and several well documented examples are given of the manipulation of milk composition by dietary means.