Avocado, sunflower and olive oils as replacers of pork back-fat in burger patties: effect on lipid composition, oxidative stability and quality traits

The present study investigates the effects of avocado, sunflower and olive oils used as back-fat replacers, on the fatty acid composition, oxidative stability, volatiles profile and color and texture properties of cooked pork patties. The vegetable oils modified the fatty acid profiles of the patties by lowering the percentages of SFA (from 36.96% to ~ 25.30%) and reducing the atherogenic index (from 0.41 to ~ 0.24). Vegetable oils had higher amounts of antioxidant compounds such as tocopherols (10.8-53.9 mg/100 g) than back-fat (5.9 mg/100 g). Consistently, patties manufactured with the oils had significantly lower amounts of lipid and protein oxidation products than control patties. Avocado oil contributed with specific aroma-active terpenes to patties and had a significant impact on particular color and texture parameters. The results from this study highlight the technological applications of the vegetable oils as food ingredients in the design of healthier meat commodities.     

Avocado by-products as inhibitors of color deterioration and lipid and protein oxidation in raw porcine patties subjected to chilled storage

Processing of avocados generates an important amount of by-products such as peels and seeds that are rich in bioactive substances with proven radical suppressing activities. The objective of this study was to evaluate the effectiveness of peel and seed extracts from two avocado varieties-'Hass' and 'Fuerte'-as inhibitors of lipid and protein oxidation and color deterioration of raw porcine patties during chilled storage (4 °C/15 days). Avocado extracts significantly (p<0.05) reduced the loss of redness and the increase of lightness during storage of porcine patties. 'Fuerte' extracts were more efficient at inhibiting discoloration of chilled patties than 'Hass' extracts. Patties treated with avocado extracts had significantly lower amounts of TBA-RS than control ones throughout the storage. 'Hass' avocado extracts significantly inhibited the formation of protein carbonyls in chilled patties at day 15. The present results highlight the potential usage of extracts from avocado by-products as ingredients for the production of muscle foods with enhanced quality traits.     

Effect of feeding fat sources on the quality and composition of lipids of precooked ready-to-eat fried chicken patties

The effect of feeding fat sources on the quality and composition of lipids of raw meat and precooked ready-to-eat fried chicken patties was studied. Two homogeneous groups of broilers were fed with animal fats and vegetable oils, respectively. A traditional technology (flash-frying and humid steam-convection oven cooking) was employed to produce the patties. Lipid hydrolysis (total fatty acids, free fatty acids and diacylglycerols) and oxidation (peroxide value (POV) and cholesterol oxidation products (COPs)) were evaluated in the initial, intermediate and final products. Lipid hydrolysis and oxidation were more intense in ground raw meat obtained with animal and vegetable fat integration, respectively. However, these differences tended to decrease along the technological process, due to the addition of other ingredients and the oil absorption. Although flash-frying and humid steam-convection oven cooking promoted lipid degradation, the overall quality of the precooked chicken cutlets was acceptable (low POV and COPS values) and greatly depended on the quality of the raw meat and the frying oil.     

Development of a Hamburger Patty with Healthier Lipid Formulation and Study of its Nutritional, Sensory, and Stability Properties

A modified beef hamburger patty enriched in polyunsaturated n−3 fatty acids and α-tocopherol was developed using technological procedures. Raw meat was obtained from low-cost parts of beef carcasses (brisket and flank) to which visible fat and connective tissue was manually eliminated and substituted by a mixture of pre-emulsified olive, corn, and deodorized fish oil. The developed product was analyzed and compared to conventional beef hamburger patties for their proximate composition, fatty acid profile, and consumer acceptability. The effects of cooking on the fat content and fatty acid profile of the developed product were investigated. Additionally, the lipid oxidation and surface color stability of modified and conventional hamburgers were investigated during 8 days of refrigerated storage while packaged in a modified atmosphere (20%/80% CO₂/O₂) and subsequently cooking. The developed product showed significantly lower total fat, cholesterol, sodium, and calorie content than beef hamburger patties manufactured using conventional procedures. In addition, the polyunsaturated fatty acids/saturated fatty acids and n−6/n−3 ratios matched nutritional recommendations more closely. No evidence of lipid oxidation was found for the modified hamburger patties during 8-day storage period, and surface color, especially redness, was more stable than in conventional ones. Additionally, consumer acceptability of the developed patty after it was cooked was acceptable and similar to that of conventional products. The modified hamburger patty developed by technological methods is viable and can be considered a useful food to preclude nutritional disorders or to assist in nutritional regimens.     

Low-fat frankfurters formulated with a healthier lipid combination as functional ingredient: microstructure, lipid oxidation, nitrite content, microbiological changes and biogenic amine formation

Oil (healthier lipid combination of olive, linseed and fish oils)-in-water emulsions stabilized with different protein systems (prepared with sodium caseinate (SC), soy protein isolate (SPI), and microbial transglutaminase (MTG)) were used as pork backfat replacers in low-fat frankfurters. Microstructure, lipid oxidation, nitrite content, microbiological changes and biogenic amine formation of frankfurters were analyzed and found to be affected by the type of oil-in-water emulsion and by chilling storage (2° C, 41 days). Although the lipid oxidation levels attained were low, replacement of animal fat by healthier oil combinations in frankfurter formulation did promote a slight increase in lipid oxidation. Residual nitrite was affected (P < 0.05) by formulation and storage. Only 51-61% of the added nitrite was detectable in the product after processing and 17-46% at the end of storage. The microbial population was low in all formulations during chilling storage. Spermine was the most abundant amine (19-20 mg/kg), but similar in level to all samples.     

Practical use of surimi-like material made from porcine longissimus dorsi muscle for the production of low-fat pork patties

This study evaluates the effect of replacing fat with surimi-like material (SLM) made from the porcine longissimus dorsi muscle on the physicochemical and sensory characteristics of pork patties. Pork patties were produced with different levels of fat and SLM using a commercial method. Pork patties produced with 20% SLM had the lowest fat content (1.76%, P < 0.001), and had a higher cooking yield (87.41 vs. 78.57%, P < 0.05) and less shrinkage (4.01 vs. 9.02%, P < 0.001) than patties produced with 20% back-fat (control). Moreover, patties produced with SLM exhibited more acceptable organoleptic characteristics, including tenderness (P < 0.01) and overall acceptability (P < 0.001), than full-fat control patties. These results indicated that SLM cannot only be used as a fat replacer, but that it also improves the physicochemical and sensory characteristics of low-fat pork patties.     

Sodium Alginate Plus Modified Tapioca Starch Improves Properties of Low-Fat Beef Patties

Sodium alginate (A) in combination with modified tapioca starch (T) was evaluated in low-fat beef patties cooked by broiling or grilling to 68 or 74°C. Added water was used with AT formulations at 7% (AT7) or 14% (AT14) levels. In comparisons with all-beef patties (8 and 20% fat), AT provided improvements in tenderness, juiciness and cooking yields without increasing fat retention or affecting beef flavor. In sensory comparisons with 14 commercially processed, low-fat beef patties, AT7 and 14 patties received the highest ratings. Combined use of A and T would provide improved acceptability of low-fat patties over that from using single fat replacers.     

Effect of cooking on the chemical composition of low-salt, low-fat Wakame/olive oil added beef patties with special reference to fatty acid content

Changes in chemical composition, with special reference to fatty acids, as affected by cooking, were studied in low-salt (0.5%)/low-fat patties (10%) with added Wakame (3%) and partial or total replacement of pork backfat with olive oil-in-water emulsion. The addition of Wakame and olive oil-in-water emulsion improved (P < 0.05) the binding properties and the cooking retention values of moisture, fat, fatty acids and ash, which were close to 100%. Partial and total replacement of animal fat with olive oil-in-water emulsion reduced (P < 0.05) saturated fatty acids (SFAs), while total replacement also reduced (P < 0.05) polyunsaturated fatty acid (PUFAs) contents. The fatty acid concentration in cooked patties was affected by product formulation. Unlike the case of all animal fat patties, when olive oil was added the cooking process increased (P < 0.05) SFAs, monounsaturated fatty acids (MUFAs) and PUFA n-3 (linolenic acid) and n-6 (linoleic acid) contents. Cooked formulated patties with seaweed and partial or total replacement of pork backfat by oil-in-water emulsion and with seaweed added were less calorie-dense and had lower SFAs levels, while samples with olive oil had higher MUFAs levels.     

Sensory, Shear, and Cooking Properties of Lower-Fat Beef Patties Made with Inner Pea Fiber

Lower fat (10% and 14%) ground beef patties containing inner pea fiber as dry powder or as part of a high fat mixture were compared to all‐beef patties (10%, 14%, and 18% fat). Patties processed with pea fiber had improved tenderness and cooking yields and showed less change in thickness during cooking, but required longer cooking times to reach 71 °C compared to all‐beef controls. Beef flavor intensity of pea fiber patties did not differ from 10% and 14% fat all‐beef patties. Different forms of pea fiber usage produced similar patty properties. Use of inner pea fiber in lower fat beef patties improved tenderness and cooking yield, without negative effects on juiciness and flavor.     

Replacement of Beef Fat with Partially Hydrogenated Plant Oil in Lean Ground Beef Patties

Partially hydrogenated plant oils (corn, cottonseed, palm, peanut and soybean) were substituted (in part) for beef fat in lean (10% fat) ground beef patties to improve nutrient content of ground beef. Effects of such addition on composition and consumer acceptability were evaluated. Addition of hydrogenated plant oils had little effect on composition of raw or cooked patties. Those containing hydrogenated corn or palm oil were not different (P>0.05) from all-beef patties in cooking loss or overall acceptability. Therefore substitution of hydrogenated oils for beef fat in production of lean ground beef patties may be feasible.     

Variability in temperature distribution and cooking properties of ground pork patties containing different fat level and with/without salt cooked by microwave energy

This study was carried out to evaluate the cooking effects of fat level (10% and 20%) with and without NaCl (1.5%) on the microwave cooking pattern and properties of ground pork patties. Each patty was cooked from a thawed state to 76.7°C in a microwave oven with full power (900W). Cooking rate in patties produced without salt was not affected by fat level, but the addition of salt in pork patties decreased cooking rate, regardless of fat levels. The temperatures at the edges of the patties increased faster than those at the center or the mid-way positions. In the patties with NaCl, the temperature of the center position was higher than that of the mid-way position. Patties containing salt within the same fat level had higher moisture content and lower fat content than those without salt, although no significant differences in compositional properties were observed between the center, midway, or edge positions. Total cooking loss, drip loss, and reduction in diameter and thickness were higher in patties with 20% fat compared to those with 10% fat, but the addition of salt resulted in reduction, regardless of fat level. Also, the addition of salt increased the redness and reduced yellowness of the cooked products.     

Characteristics of low-fat meat emulsion systems with pork fat replaced by vegetable oils and rice bran fiber

The effects of vegetable oils prepared from olive, corn, soybean, canola, or grape seed, and rice bran fiber on the composition and rheological properties of meat batters were studied. Pork fat at 30% in the control was partially replaced by one of the vegetable oils at 10% in addition to reducing the pork fat to 10%. The chemical composition, cooking characteristics, texture properties, and viscosity of low-fat meat batters were analyzed. The moisture, protein, ash content, uncooked and cooked pH values, b^∗-value, hardness, cohesiveness, gumminess, chewiness, and viscosity of meat batters with vegetable oil and rice bran fiber were all higher than the control. In addition, batters supplemented with vegetable oil and rice bran fiber had lower cooking loss and better emulsion stability. Low-fat meat batters with reduced pork fat content (10%) and 10% vegetable oil plus rice bran fiber had improved characteristics relative to the regular fat control.     

Virgin Olive Oil as Frying Oil

Frying is one of the oldest cooking procedures and is still among the most popular ones for food preparation. Due to their unique sensory characteristics, fried foods are consumed often and with pleasure. During frying, part of the oil is absorbed by the food, thereby becoming part of our diet; most interestingly, in the Mediterranean area approximately 50% of total fat intake is provided by cooking fats. Olive oil is the key lipid component of the Mediterranean diet, the health‐promoting effects of which have been largely attributed to olive oil intake. Olive oil is unique among vegetable oils due to its desirable lipid profile and some of its minor components. Scientific evidence now indicates that during frying olive oil behavior is usually equal or superior to that of refined vegetable oils. Herein, an overview of virgin olive oil performance under frying is given, with special reference to the fate of olive oil microconstituents. The compositional changes of foods fried in olive oil are also reviewed and discussed in detail.     

EFFECTS OF AVOCADO FRUIT PUREE AND OATRIM AS FAT REPLACERS ON THE PHYSICAL, TEXTURAL AND SENSORY PROPERTIES OF OATMEAL COOKIES

ABSTRACT

This study was conducted to investigate the effectiveness of partial replacement (50% level) of butter fat by two different fat replacers (avocado puree and Oatrim) on the physical, textural and sensory properties of oatmeal cookies. Compared with the control cookie, both fat‐reduced cookies had greater heights, reduced spreads, increased % moisture loss and higher water activities (P < 0.05). Textural measurements made using the TA.XT Plus Texture Analyzer showed the fat‐reduced cookies to be tougher and less brittle (P < 0.05). Appearance was the only sensory category in which a significant difference was seen (P < 0.05). Both avocado and Oatrim cookies were found to be overall acceptable, and at the 50% level of fat replacement, the total fat content for the avocado and Oatrim cookies decreased by 35 and 39%, respectively.

PRACTICAL APPLICATIONS

When incorporated into an overall healthy diet, reduced‐fat foods made with fat replacers can play an important role in helping consumers reach and maintain their goal of reducing consumption of dietary fat. Results from this study indicate that cookies with acceptable physical, textural and sensory properties could be produced when 50% of the fat is replaced by Oatrim and avocado fat replacers. Dietitians should be aware of such fat replacers. Improved nutritional content, acceptability, ease of preparation and low cost make avocado puree a viable fat replacement option for use in home‐baked products. This data can also serve as a resource to further explore the utilization of Oatrim in developing commercially prepared low‐fat cookies and other baked products.

     

Inclusion of blended lipid solutions as functional ingredients to alter the fatty acid profile of beef patties

Beef patties formulated to contain beef fat, plant oil, and a rosemary extract to increase unsaturated fatty acid content and maintain desirable sensory attributes were compared to control beef patties formulated without plant oils. Treatment patties were formulated to a fat content of 10% or 20% by combining beef trimmings (6% fat) with 4% or 14% addition of a lipid blend. Blends contained 57% beef tallow, 0.3% rosemary extract, and 43% of high oleic safflower oil (SO), olive oil (OO), or corn oil (CO). Lipid oxidation, as measured by TBA values, of treatment patties were similar to control patties after 0 and 3 d of refrigerated (2 °C) storage and up to 56 d of frozen (-10 °C) storage. Cooked lipid blend patties having a fat content of 10% or 20% were similar to or higher than control patties for juiciness and were no different for other sensory attributes evaluated. At fat levels of 10% or 20%, oleic acid (18: 1) in cooked SO patties (46.1% and 50.3%, respectively) and OO patties (43.8% and 48.1%, respectively) was higher than the control (37.3% and 37.6%, respectively). Unsaturated to saturated fatty acid ratios at the 10% or 20% fat levels were higher in SO (1.37 and 1.60, respectively) and CO (1.40 and 1.48, respectively) patties than the control (0.97 and 0.94, respectively). Beef patties manufactured with varying lipid blends increased unsaturated fatty acid content and were similar in physical characteristics and sensory attributes of all beef patties formulated without lipid blends. PRACTICAL APPLICATION: The development of healthier beef products that will be more appealing to consumers has long been an industry goal. The authors believe that lipid blends such as the one used in this study could be used to create such products, not only in the form of beef patties, but any number of processed meat products. Because the materials and equipment used to create the lipid blends in this study are widely available, their incorporation into meat products would represent a small capital investment. This is an important factor in bringing a reasonably priced, healthier product to consumers.     

Process optimization and consumer acceptability of salted ground beef patties cooked and held hot in flavored marinade

Food safety is paramount for cooking hamburger. The center must reach 71 °C (or 68 °C for 15 s) to assure destruction of E. coli O157:H7 and other food pathogens. This is difficult to achieve during grilling or frying of thick burgers without overcooking the surface. Thus, the feasibility of partially or completely cooking frozen patties in liquid (93 °C water) together with hot holding in liquid was investigated. Initial studies demonstrated that compared to frying, liquid cooking decreased (P < 0.05) patty diameter (98 compared with 93 mm) and increased (P < 0.05) thickness (18.1 compared with 15.6 mm). Liquid cooked patties had greater weight loss (P < 0.05) immediately after cooking (29 compared with 21%), but reabsorbed moisture and were not different from fried patties after 1 h hot water holding (61 °C). Protein and fat content were not affected by cooking method. However, liquid cooked patties were rated lower (P < 0.05) than fried patties for appearance (5.7 compared with 7.5) and flavor (5.9 compared with 7.5). An 8-member focus group then evaluated methods to improve both appearance and flavor. Salted, grill-marked patties were preferred, and caramel coloring was needed in the marinade to obtain acceptable flavor and color during liquid cooking or hot holding. Patties with 0.75% salt that were grill-marked and then finish-cooked in hot marinade (0.75% salt, 0.3% caramel color) were rated acceptable (P < 0.05) by consumers for up to 4 h hot holding in marinade, with mean hedonic panel ratings > 7.0 (like moderately) for appearance, juiciness, flavor, and texture. PRACTICAL APPLICATION: Grill-marked and marinade-cooked ground beef patties reached a safe internal cooking temperature without overcooking the surface. Burgers cooked using this method maintained high consumer acceptability right after cooking and for up to 4 h of hot holding. Consumers and foodservice operations could use this method without specialized equipment, and instead use inexpensive and common equipment such as a soup pot or a restaurant steam table. Use of marinades (salt/caramel color or others) in this cooking and holding method provides a nearly endless culinary flavoring opportunity.     

THE INFLUENCE OF COOKING METHOD ON THE QUALITY OF PORK PATTIES

Pork patties were subjected to traditional frying, cooking in a microwave oven (microwaves  +  grill), hot air cooking in a cyclojet (Electrim JI-9101 RP, Taiwan) and cooking in a steam-convection (combi) oven (hot air  +  30% steam) (BECK FCV 4 EDS, BECK GmbH, Jagsthausen, Germany). Products cooked in the combi oven (BECK FCV 4 EDS) were characterized by the smallest cooking loss, the highest retention of water and the lowest content of fat compared to other samples. The content of hydroxymethylfurfural in fried and cyclojet-cooked patties was almost twofold higher than in microwave and combi oven-cooked samples. The intensity of lipid oxidation was also higher in fried and cyclojet-cooked meat than in the other two products. The intensity of meat flavor was the strongest in the combi oven-cooked patties. All products were characterized by a low intensity of fatty flavor. The highest scores for overall acceptability were given to the combi oven-cooked patties, whereas the lowest scores were given by the panelists to the microwave-cooked patties.

PRACTICAL APPLICATIONS

Pork patties are an important meat product both in catering production for direct consumption and in convenience food industry when intended for refrigerated or frozen storage. As cooking is a main stage in preparation of patties for consumption, it is essential to use a method of cooking that ensures the high nutritional and sensory quality of products. Most often, pork patties are subjected to deep frying or traditional frying; however, several other cooking methods can be used. The present work shows that the combi oven cooking enables production of patties of desirable nutritional and sensory characteristics and low content of unfavorable compounds.     

Contents and Retention of Nutrients in Extra Lean, Lean and Regular Ground Beef

Contents and retention of nutrients in raw and cooked (broiled, roasted and grilled to medium-well stage) ground beef patties were established. Fat levels of the raw patties were 18.4, 21.5, and 27.0%. Cooking yields were slightly lower and energy contents were higher for patties containing 27.0% fat than 18.4 or 21.5%. Total lipids, energy content, thiamin and pantothenic acid were the least retained nutrients while zinc was the highest. Generally, retentions after broiling or grilling were the same but were higher than after roasting. The polyunsaturated to saturated fatty acid ratios (P/S) rose slightly after cooking. For most nutrients, differences due to fat levels or cooking methods appear to be too small to be of practical nutritional significance.     

Enhancement of the nutritional status of beef patties by adding flaxseed flour

Flaxseed flour was used as a functional ingredient in the production of beef patties. Beef patties were produced with five different formulations; the addition of 3%, 6%, 9%, 12% and 15% flaxseed flour. Control samples were formulated with 10% and 20% fat addition. Raw and cooked beef patties were analyzed for moisture, protein, fat, ash, pH, color parameters and fatty acid profiles. Beef patties were evaluated for cooking loss and sensory properties. Fat and ash content of raw patties increased, while moisture and protein content decreased with increased flaxseed flour. The same trend (except fat content) was also observed after cooking. The addition of flaxseed flour did not affect pH values of raw and cooked beef patties. The addition of flaxseed flour improved the cooking loss but, increased the energy value (as kcal/100 g). L and a values of raw beef patties containing flaxseed flour were close to controls with 10% fat. α-linolenic acid content of raw and cooked beef patties increased as the level of flaxseed flour increased. The PUFA/SFA ratio increased from 0.04 in the control with 10% fat to 0.62 in the raw beef patties with 15% flaxseed flour. The n-6/n-3 ratio decreased from 5.76 in the control with 10% fat to 0.36 in the raw beef patties with 15% flaxseed flour. The nutritional status of beef patties was enhanced with minimal composition and sensory changes with 3% or 6% flaxseed flour addition.     

Effects of replacing pork back fat with vegetable oils and rice bran fiber on the quality of reduced-fat frankfurters

The effects of substituting olive, grape seed, corn, canola, or soybean oil and rice bran fiber on the chemical composition, cooking characteristics, fatty acid composition, and sensory properties of low-fat frankfurters were investigated. Ten percent of the total fat content of frankfurters with a total fat content of 30% (control) was partially replaced by one of the vegetable oils to reduce the pork fat content by 10%. The moisture and ash content of low-fat frankfurters with vegetable oil and rice bran fiber were all higher than the control (P < 0.05). Low-fat frankfurters had reduced-fat content, energy values, cholesterol and trans-fat levels, and increased pH, cooking yield and TBA values compared to the controls (P < 0.05). Low-fat frankfurters with reduced-fat content plus rice bran fiber had sensory properties similar to control frankfurters containing pork fat.