Maurice G. O'Sullivan

Consumer acceptability and physiochemical characteristics of modified atmosphere packed beef steaks.

The objective of this study was to investigate the physiochemical changes of beef steaks packed under various combinations of gasses and the relationship between consumer perception of flavour and acceptability of modified atmosphere packed beef steaks during retail display. Experimental gas atmospheres included: 40%, 50%, 60%, 70%, and 80% oxygen, with all packs containing 20% CO(2) and the make up gas N(2). Steaks were stored at 4°C for 12 days and tested for lipid and protein oxidation, heme iron, colour, oxymyoglobin concentration, Warner-Bratzler shear force (WBSF) and consumer acceptability for the resulting cooked meat. The results from 134 consumers indicated a directional preference for the steaks stored in packs containing 40% and 80% oxygen. Samples with high oxygen levels, particularly the O(2)60 and O(2)70 treatments, were positively and significantly (P<0.01) correlated to sensory toughness, and significantly (P<0.05) negatively correlated to juiciness, as determined by consumers. However, the O(2)40 samples were most negatively (P<0.001) correlated to toughness and positively (P<0.01) correlated to juiciness, which shows that, in general, these higher O(2) levels, >40%, imparted greater meat toughness as determined by the consumers. The greater directional acceptance of the O(2)40 samples may be linked to the consumer perceived reduction in sensory toughness and increases in juiciness.

The impact of salt and fat level variation on the physiochemical properties and sensory quality of pork breakfast sausages.

The sensory and physiochemical properties of sausages with varying fat and salt levels were investigated. Twenty eight sausages were produced with varying concentrations of fat (22.5%, 27.5%, 32.5%, 37.5% w/w) and salt (0.8%, 1%, 1.2%, 1.4%, 1.6%, 2%, 2.4% w/w). Sausages were assessed instrumentally for colour, moisture, fat, cooking loss and texture profile analysis. Consumers (n = 25), evaluated each product in duplicate for colour, texture, tenderness, juiciness, salt taste, meat flavour, off-flavour and overall acceptability using a hedonic scale. Lowering fat produced products which consumers rated as less dark in colour, tougher, less juicy and taste less salty than higher fat products. However, no significant preferred sample was found amongst consumers. Salt reduction in products produced sausages which consumers rated as paler in colour, more tender and with greater meat flavour than higher salt containing products. The sausages containing 1.4% and 1.0% salt were significantly (P<0.01) found to be more acceptable to consumers than other salt levels.

Effect of varying salt and fat levels on the sensory and physiochemical quality of frankfurters

The sensory and physiochemical properties of frankfurters with varying fat and salt levels were investigated. Twenty frankfurter formulations were produced with varying concentrations of fat (10%, 15%, 20%, 25% w/w) and salt (1%, 1.5%, 2%, 2.5%, 3% w/w). Frankfurters were assessed instrumentally for colour, moisture, fat, cooking loss and texture profile analysis. Consumers (n=25) evaluated each product in duplicate for colour, coarseness, tenderness, juiciness, salt taste, meat flavour, off-flavour and overall acceptability using a hedonic scale. Salt levels below 1.5% were shown to have a negative effect on consumer acceptability, with 2.5% salt concentration being the most accepted (P<0.001) by consumers. However, frankfurters containing the lower fat levels 10% and 15% fat with higher salt levels (2.5-3%) were significantly the most acceptable variants to consumers. Samples containing less fat and salt were found to be tougher, less juicy and had greater cooking losses. Thus salt perception is very important for consumer acceptability, but fat levels can be potentially reduced without significantly affecting overall acceptability.

Effect of marinating time and low pH on marinade performance and sensory acceptability of poultry meat.

The effects of marinating time (30, 60, 120 and 180 min) and acidic marinade pH (3.0, 3.2, 3.4, 3.6, 3.8, 4.0 and 4.2) on the instrumental and sensory properties of cooked Chinese-style marinated chicken were investigated. With increasing marinating time up to 180 min, a significant (P<0.05) increase in surface redness (a* value) and the dark pink sensory attribute was observed, along with a corresponding decrease in lightness (L* value) and colour penetration. Increased marinating times of 120-180 min were found to produce more acceptable end products with increased scores for colour, aroma and flavour attributes. Marinade uptake was greater at higher marinade pH levels of 3.8, 4.0 and 4.2, with the highest marinade uptake (3.34%) recorded at pH 4.0. As changes to core meat pH were not observed, the effect of marinating time (up to 180 min) and marinade pH on the instrumental and sensory properties of Chinese-style marinated chicken were located principally at the surface of samples. Consumers considered surface colour as contributing to acceptability of marinated chicken to a greater degree compared to colour penetration.

Effect of varying salt and fat levels on the sensory quality of beef patties.

The interactive effects of varying levels of salt and fat on the sensory and physiochemical properties of beef patties were investigated. Twenty beef patties with varying levels of fat (30% 40% 50% 60% w/w) and salt (0.5%, 0.75% 1.0% 1.25% 1.5% w/w) were manufactured. All samples were assessed instrumentally for colour, moisture, fat, cooking loss and texture profile analysis. Sensory consumer evaluation was conducted using 25 consumers. The consumers rated each coded product, in duplicate, in terms of colour, texture, tenderness, juiciness, salt, taste, meat flavour, off flavour and overall acceptability. The data indicate that the most consumer acceptable beef patty was that containing 40% fat with a salt level of 1%. This is a 20% decrease in fat and a 50% decrease in salt levels when compared to commercial patties available in Ireland and the UK.

The distribution of dietary vitamin E in the muscles of the porcine carcass

The objectives of this study were to determine the effect of dietary vitamin E supplementation on tissue α-tocopherol levels in muscles in the porcine carcass. Pigs (n = 9), were selected at random and divided into three groups (n = 3) and fed diets containing 0 (basal), 20, 160 mg dl-α-tocopheryl acetate/kg feed for a period of 130 days prior to slaughter. After slaughter carcasses were split centrally and chilled at 4 °C × 24 h. Muscles (n = 37) were identified and removed from the left side of each animal for each dietary group and stored at -20 °C until required. The mean α-tocopherol levels in pork muscle tissue were significantly (p < 0.05) higher in the high-supplemented group (160 mg α-tocopheryl acetate/kg of feed) compared with the low-supplemented (20 mg/kg of feed) and basal groups (unsupplemented). In the supplemented samples, the muscles of the thoracic limb (4.8-9.9 mg α-tocopherol/kg of tissue) and neck and thorax (3.7-9.2 mg/kg) contained the greatest levels of α-tocopherol compared the muscles of the pelvic limb (4-5.6 mg/kg) and back (2.5-3.5 mg/kg).

Sensory comparison of commercial low and high oxygen modified atmosphere packed sirloin beef steaks.

The objectives of this study were to investigate the effects of using commercially low and high modified atmosphere packaging (MAP) on quality characteristics of sirloin beef steaks. Gas mixtures used included 80% O(2):20% CO(2) (O(2)80), 70% O(2)/30% CO(2) (O(2)70) and 50% O(2)/30% CO(2):20% N(2) (O(2)50) and for commercial packs O(2)75 ± 5%, CO(2)25 ± 5%, <5% N(2)-(O(2)Com). All samples were packed in similar tray and packaging film formats. The experimental parameters monitored included microbiological, physiochemical and sensory measurements (naïve assessors). Microbial counts did not exceed the recommended legal ranges over the storage period. However the numbers of LAB (lactic acid bacteria) were the highest for commercially-packed samples (O(2)Com) in comparison to laboratory packaged samples (O(2)80, O(2)70 and O(2)50). Commercially-packaged samples eventually spoiled due to the occurrence of off-flavours and off-odours and subsequently were the least acceptable to sensory naïve assessors.

Impact of varying salt and fat levels on the physicochemical properties and sensory quality of white pudding

Twenty-five white pudding formulations were produced with varying fat contents (20%, 15%, 10%, 5%, 2.5% w/w) and varying sodium contents (1.0%, 0.8%, 0.6%, 0.4%, 0.2% w/w). Compositional analysis, cooking loss, colour and texture profile analysis were determined. Sensory acceptance testing using untrained assessors (n=25-30) was performed in duplicate on products for liking of appearance, flavour, texture, colour and overall acceptability, followed by ranking descriptive analysis using the descriptors grain quantity, fatness, spiciness, saltiness, juiciness, toughness and off-flavour. Puddings containing higher sodium levels (1.0%, 0.8%) were the most accepted, with the exception of those with the lowest fat content. Lower fat and salt puddings were tougher, less juicy, less spicy, lighter and had a more intense yellow colour (P<0.05). However, the pudding sample containing 15% fat and 0.6% sodium was highly accepted (P<0.05), thereby satisfying the sodium target (0.6%) set by the Food Safety Authority of Ireland (FSAI, 2011).

Impact of ingredient replacers on the physicochemical properties and sensory quality of reduced salt and fat black puddings

Twenty-two black puddings possessing different fat (10%, 5%) and sodium (0.6%, 0.4%) levels were used as base formulations for 11 different salt and fat replacers. Compositional, physicochemical and sensory analyses were conducted. Black pudding samples with 5% fat and 0.6% sodium containing potassium chloride (KCl), potassium chloride and glycine mixture (KClG), and seaweed, respectively, and 10% fat and 0.4% sodium containing carrageen were rated higher (P<0.05) for spiciness and saltiness. Samples with 10% fat and 0.4% sodium containing KClG were rated positively (P<0.05) to fatness. Samples with 5% fat and 0.6% sodium containing pectin and a combination of potassium citrate, potassium phosphate and potassium chloride (KCPCl), as well as samples containing 10% fat and 0.4% sodium with waxy maize starch (WMS) were liked (P<0.05) for flavor and overall acceptance. The Food Safety Authority of Ireland (FSAI) recommends a sodium target level of 0.6% and an even lower sodium level (0.4%) was achieved.

European consumer attitudes on the associated health benefits of neutraceutical-containing processed meats using Co-enzyme Q10 as a sample functional ingredient

This study accumulated European consumer attitudes towards processed meats and their use as a functional food. A survey was set up using an online web-application to gather information on consumer perception of processed meats as well as neutraceutical-containing processed meats. 548 responses were obtained and statistical analysis was carried out using a statistical software package. Data was summarized as frequencies for each question and statistical differences analyzed using the Chi-Square statistical test with a significance level of 5% (P<0.05). The majority of consumer attitudes towards processed meat indicate that they are unhealthy products. Most believe that processed meats contain large quantities of harmful chemicals, fat and salt. Consumers were found to be very pro-bioactive compounds in yogurt style products but unsure of their feelings in meat based products, which is likely due to the lack of familiarity to these products. Many of the respondents were willing to consume meat based functional foods but were not willing to pay more for them.