Effects of varying levels of vegetable juice powder and incubation time on color, residual nitrate and nitrite, pigment, pH, and trained sensory attributes of ready-to-eat uncured ham

ABSTRACT:  Vegetable juice powder (VJP) and a starter culture containing Staphylococcus carnosus have been identified as necessary ingredients for the manufacture of uncured, no-nitrate/nitrite-added meat products with quality and sensory attributes similar to traditional cured products. The objectives of this study were to determine the effects of varying concentrations of VJP and incubation time (MIN-HOLD) on quality characteristics, including lipid oxidation, color, and cured meat pigment concentrations, of ham over a 90-d storage period, compare residual nitrate and nitrite content, and determine if differences exist in sensory properties of finished products. Four ham treatments (TRT) (TRT 1: 0.20% VJP, 0 MIN-HOLD; TRT 2: 0.20% VJP, 120 MIN-HOLD; TRT 3: 0.35% VJP, 0 MIN-HOLD; TRT 4: 0.35% VJP, 120 MIN-HOLD) and a sodium nitrite-added control (C) were used for this study. No differences ( P > 0.05) were observed between TRTs and C for CIE L *, a *, b *, and cured color measured by reflectance ratio. Lipid oxidation (TBARS) for combined TRTs and C revealed little change over time while the C had less ( P < 0.05) lipid oxidation than TRTs 2 and 4 for combined days. No differences ( P > 0.05) were reported for cured pigment concentration between TRTs and C. Trained sensory panel intensity ratings for ham and vegetable aroma, and flavor, color, and firmness showed that a high concentration (0.35%) of VJP resulted in the highest scores for undesirable vegetable aroma and flavor. Treatment combinations with a low concentration (0.20%) of VJP were comparable to the C for all sensory attributes.     

Effects of vegetable juice powder concentration and storage time on some chemical and sensory quality attributes of uncured, emulsified cooked sausages

ABSTRACT:  Uncured, no-nitrate/nitrite-added meat products can be manufactured with vegetable juice powder (VJP) and a starter culture containing Staphylococcus carnosus , resulting in quality and sensory attributes similar to traditional cured products. The 1st objective of this study was to determine the effects of varying concentrations of VJP and incubation times (MIN-HOLD) on quality characteristics, including lipid oxidation, color, and cured meat pigment concentrations, of emulsified-frankfurter-style-cooked (EFSC) sausages over a 90-d storage period. The 2nd objective was to compare residual nitrate and nitrite content resulting from different processing treatments and the 3rd objective was to assess sensory properties of finished products. Four EFSC sausage treatments (TRT) (TRT 1: 0.20% VJP, 30 MIN-HOLD; TRT 2: 0.20% VJP, 120 MIN-HOLD; TRT 3: 0.40% VJP, 30 MIN-HOLD; TRT 4: 0.40% VJP, 120 MIN-HOLD) and a sodium nitrite-added control (C) were used for this study. No differences for lipid oxidation (TBARS) between any TRTs and C or over time were observed. No differences ( P > 0.05) for CIE L * values were found between TRTs. CIE a * and reflectance ratio values revealed that TRTs 2, 4, and C were redder than TRTs 1 and 3 at day 0. Trained sensory intensity ratings for cured aroma, cured color, cured flavor, uniform color, and firmness determined that all but TRT 1 were similar to C. These results indicate a longer incubation time (120 compared with 30 min) was found more critical than VJP level (0.20% or 0.40%) to result in products comparable to a sodium nitrite-added control.     

Investigating quality attributes and consumer acceptance of uncured, no-nitrate/nitrite-added commercial hams, bacons, and frankfurters

ABSTRACT:  Increasing demands for natural, organic, and/or preservative-free foods have resulted in the consumer availability of uncured, no-nitrate/nitrite-added processed meat and poultry products. A comprehensive understanding about the quality and sensory attributes of commercially available uncured products is unclear. The objective of this study was to determine if quality and sensory differences exist between uncured and cured meat products. Five different commercial brands (Brands A to E; 4 uncured, no-nitrate/nitrite-added, and 1 nitrite-added) of 3 product types (hams, frankfurters, and bacons) were obtained from retail supermarkets. The samples were evaluated for color, pigment content, pH, lipid oxidation, residual nitrate and nitrite content, and consumer acceptance. All brands from all product types evaluated, except for 1 bacon (Brand B), had cured color, aroma, and flavor attributes similar to the nitrite-added control (Brand E). All product types and brands contained residual nitrate and residual nitrite except for Brands B and D bacons (< 1 ppm nitrite). Lipid oxidation as measured by 2-thiobarbituric acid reactive substances revealed a large variation in the occurrence of lipid oxidation both between and within product types, with frankfurters reporting the highest levels. Color measurements indicated the majority of the brands within each product type were similar to the control. Consumer sensory ratings for surface/lean color, aroma, flavor, texture, and overall acceptance determined that variation existed. Brand E (nitrite-added control) and 1 uncured, no-nitrate/nitrite-added brand for each product type were not different ( P > 0.05) for overall acceptance and received higher scores ( P < 0.05) than all other brands within each product type.     

Determining the impact of varying levels of cherry powder and starter culture on quality and sensory attributes of indirectly cured, emulsified cooked sausages

Indirect curing is a process that utilizes ingredients high in naturally occurring nitrate and a nitrate reducing bacterial starter culture (SC) to provide quality and sensory attributes similar to nitrite-added cured meats. The objective of this study was to determine the effects varying concentrations of starter culture and the addition of cherry powder (CP) had on improving quality and sensory attributes of indirectly cured sausages. Four treatments (TRTs) (TRT 1: low SC+no CP; TRT 2: low SC+CP; TRT 3: high SC+no CP; and TRT 4: high SC+CP) and a sodium nitrite-added (156 ppm) control were investigated. Residual nitrite levels throughout storage declined most rapidly in TRTs 2 and 4 (P<0.05). Few differences existed between TRTs and C for pH, objective color, or cured pigment concentrations. Consumer sensory panel scores revealed all treatment combinations were comparable (P>0.05) to the C for all sensory attributes.     

Development of a method to manufacture uncured,no-nitrate/nitrite-added whole muscle jerky

“Natural curing” is accomplished by use of vegetable juice/powder high in naturally occurring nitrates combined with a nitrate reducing starter culture to result in indirectly “cured” products. Since the starter culture used is not water soluble, making “naturally cured” whole muscle jerky with current manufacturing techniques has been found ineffective. The objective was to investigate processes for whole muscle beef jerky that might provide cured meat characteristics similar to those of a nitrite-added control. Treatments where jerky was placed in a barrier bag during incubation were found to be the least similar to the nitrite-added control. Jerky placed in a 40.6 °C smokehouse during incubation resulted in significantly more (P < 0.05) converted cured pigment than the barrier bag treatments but less (P < 0.05) than the control. The processing methods investigated to manufacture “naturally cured” whole muscle jerky in this study were ineffective in resulting in products similar to those cured with sodium nitrite.     

正交试验优化蒸煮切片火腿工艺

研究加工工艺对低温肉制品颜色形成的影响。以蒸煮切片火腿为原料,通过单因素试验和正交试验考察亚硝酸钠添加量、混合磷酸盐添加量、蒸煮温度和滚揉/腌制时间比4种因素对产品红度值和亚硝基血红素质量分数的影响,并通过为期28d的贮藏实验,考察各正交处理组的色泽指标及非血红素铁、亚硝酸盐、pH值在贮藏中的变化情况。结果表明：最优工艺为亚硝酸钠添加量0.05g/kg、混合磷酸盐添加量5g/kg、滚揉16h后腌制8h、蒸煮温度70℃;各影响因素间无交互作用;添加亚硝酸钠越多,残留量越大,非血红素铁与色泽指标无显著相关性。     

Effects of high hydrostatic pressure and varying concentrations of sodium nitrite from traditional and vegetable-based sources on the growth of Listeria monocytogenes on ready-to-eat (RTE) sliced ham

The objective of this study was to determine the effect the source of added nitrite and high hydrostatic pressure (HHP) had on the growth of Listeria monocytogenes on ready-to-eat (RTE) sliced ham. Use of 600 MPa HHP for 3 min resulted in an immediate 3.9–4.3 log CFU/g reduction in L. monocytogenes numbers, while use of 400 MPa HHP (3 min) provided less than 1 log CFU/g reduction. With the 600 MPa HHP treatment, sliced ham with a conventional concentration of sodium nitrite (200 ppm) was not different in L. monocytogenes growth from use with 50 or 100 ppm of sodium nitrite in pre-converted celery powder. Instrumental color values as well as residual nitrite and residual nitrate concentrations for cured (sodium nitrite and nitrite from celery powder) and uncured ham formulations are discussed.     

Nitrate reductase activity of Staphylococcus carnosus affecting the color formation in cured raw ham

The influence of the nitrate reductase activity of two Staphylococcus carnosus strains used as starter cultures on the formation of nitrate, nitrite and color pigments in cured raw ham was investigated. In this context, microbiological, chemical and multivariate image analyses were carried out on cured raw hams, which were injected with different brines containing either nitrite or nitrate, with or without the S. carnosus starter cultures. During processing and storage, the viable counts of staphylococci remained constant at 6.5 log cfu/g in the hams inoculated with starter cultures, while the background microbiota of the hams processed without the starter cultures developed after 14 days. Those cured hams inoculated with S. carnosus LTH 7036 (high nitrate reductase activity) showed the highest decrease in nitrate and high nitrite concentrations in the end product, but were still in the range of the legal European level. The hams cured with nitrate and without starter culture or with the other strain, S. carnosus LTH 3838 (low nitrate reductase activity) showed higher residual nitrate levels and a lower nitrite content in the end product. The multivariate image analysis identified spatial and temporal differences in the meat pigment profiles of the differently cured hams. The cured hams inoculated with S. carnosus LTH 3838 showed an uncured core due to a delay in pigment formation. Therefore, the selection of starter cultures based on their nitrate reductase activity is a key point in the formation of curing compounds and color pigments in cured raw ham manufacture.     

Effect of pre-slaughter physiological conditions on the oxidative stability of colour and lipid during chill storage of sliced, retail packed roast ham

Pre-slaughter physiological conditions (A serving as control, B subjected to treadmill exercise immediately prior to stunning, C epinephrine injection 15 h prior to slaughter, and D epinephrine injection 15 h prior to slaughter and subjected to treadmill exercise immediately before stunning) were found to significantly affect colour and lipid oxidation of sliced, retail packed roast ham, produced from nitrite-cured (78 ppm nitrite) M. Longissimus dorsi. The pre-slaughter treatment resulted in variations in the level of glycogen, lactate, ATP and IMP and pH development as monitored in Longissimus dorsi muscles, with the lowest ultimate pH (pH(u)) in muscles from non-epinephrine treated pigs (treatments A and B). The initial tristimulus L(?)-value and the L(?)-value during chill storage of sliced roast ham packed in laminates with low or with very low oxygen transmission rate (OTR=40 and <0.5 cm(3)/m(2)/atm/24 h, respectively) were significantly affected by treatment, although the effect of the treatments was different during storage for 28 days (interaction between treatment and storage time). Roast ham from treatments A and B generally had a paler appearance (higher L(?)-values) than from treatments C and D. No differences in the initial tristimulus a(?)-values (redness) were found. During chill storage, a pronounced colour fading (decrease in a(?)-values) was seen for laminate with low OTR, with a tendency of better colour stability for treatment C than A, but with no differences for the other treatments. For laminates with very low OTR, the cured meat pigment was stable with no decreases in a(?)-values during storage. Lipid oxidation (thiobarbituric acid reactive substances, TBARS) in products in laminates with low OTR increased during storage and was significantly higher for roast ham from non-epinephrine treated pigs (A and B) than for ham from epinephrine-treated pigs (C and D). Statistical analysis relating pH and the level of glycogen, lactate, creatine phosphate, ATP and IMP in the individual pigs to the product quality parameters revealed that the ultimate level of lactate was the most important single parameter affecting product quality. After 28 days of chill storage, roast ham from pigs subjected to treatments C and D were more likely to support bacterial growth than from treatments A and B. In conclusion, the results show that pre-slaughter physiological conditions are of importance for chemical as well as for microbiological changes in retail stored roast ham.     

Effects of illumination and packaging on non-heme iron and color attributes of sliced ham

This study was designed to investigate effects of illumination and packaging on color of cooked cured sliced ham during refrigeration, and the possibility of decomposition of nitrosylheme under light and oxygen exposure. Three illumination levels and three packaging films with different oxygen transmission rates (OTRs) were used in two separate experiments during 35 days storage, and pH value, a* value, nitrosylheme, residual nitrite and non-heme iron were evaluated. Packaging OTRs had significant effects (P<0.01) on a* value, but illumination level and packaging OTR did not affect (P>0.05) nitrosylheme concentration during storage. For both groups, storage time had a significant effect (P<0.01) on a* value and nitrosylheme. Negative relationships between nitrosylheme and nitrite in the illumination group, and between nitrosylheme and non-heme iron in the packaging group were observed. Therefore, illumination level and packaging OTR had limited effects on overall pigment stability, but more discoloration and loss of redness occurred on the surface of products.     

添加葡萄球菌和微球菌对广式腊肠亚硝酸盐残留量和色泽研究

本文旨在研究葡萄球菌和微球菌对广式腊肠亚硝酸盐残留量和色泽的影响及其机制。首先将分离筛选自广式腊肠的两株优良特性菌株(葡萄球菌H33B和微球菌X142B)接种至腊肠测定相关指标,然后通过紫外扫描图谱来确定菌株是否具有转化高铁肌红蛋白能力。结果表明,接种单菌和混合菌株都能够降低腊肠中的高铁肌红蛋白含量和亚硝酸盐残留量,并且能够增加亚硝基肌红蛋白含量,其中以接种葡萄球菌和微球菌2:1时效果最好,与对照组差异明显(p0.05);紫外扫描图谱显示接种葡萄球菌的培养基中溶液出现了亚硝基肌红蛋白的特征吸收峰,并且溶液中的亚硝酸盐含量最低。这些结果表明葡萄球菌H33B具有转化高铁肌红蛋白的能力。因此添加葡萄球菌H33B的腊肠,由于其具有转化高铁肌红蛋白的能力,会形成更多的还原性肌红蛋白与亚硝酸盐反应,不仅进一步减少了亚硝酸盐含量还改善了色泽。     

Irradiation-induced Cured Ham Color Fading and Regeneration

ABSTRACT: Color stability of cured ham as a result of irradiation, packaging atmosphere, and storage time was evaluated. Sliced cured ham was packaged in aerobic or vacuum atmospheres, irradiated at 0, 1.2, 2.3, and 4.5 kGy and stored for 0 and 7 d. The ham treatments were evaluated for cured color, oxidation-reduction potential, and residual nitrite content. Irradiation decreased cured color as irradiation dose increased from 0 to 4.5 kGy as evidenced by lower a*/b* ratios and cured pigment analysis regardless of packaging atmosphere. Residual nitrite levels were also lower for the 4.5-kGy treatment compared with nonirradiated control following irradiation. Cured color was regenerated over time and resulted in higher a*/b* ratios on day 7 compared with day 0 for the 4.5-kGy treatment. Oxidation-reduction potential was decreased on day 0 and day 7 for the vacuum-packaged treatment that was irradiated at 4.5 kGy compared with the 0-kGy treatment.     

不同贮藏温度西式火腿切片品质变化规律研究

为研究市场上低温火腿切片的质量和安全性,对不同贮藏温度的真空包装火腿切片的品质变化进行动态跟踪,分析产品在0～4、7～11℃条件下,其感官品质、菌落总数、大肠菌群、色泽、pH值、水分含量、保水性和质构特性的动态变化。结果表明：两种产品品质变化的规律大致相同。0～4℃贮藏比7～11℃产品的菌落总数增长相对缓慢,pH值、水分含量,保水性和质构特性的变化更加稳定。低温更有利于保持产品品质的稳定性和安全性,延长肉品的货架期。     

Contribution of starter cultures to the proteolytic process of a fermented non-dried whole muscle ham product

Porcine longissimus dorsi muscles were cured by brine injection. Curing brine containing 15% (w/v) NaCl, 1.33% (w/v) glucose, 750 ppm sodium nitrite, and appropriate levels of either Lactobacillus sakei LAD, L. sakei LAD plus Kocuria varians FT4 (formally Micrococcus varians), L. sakei LAD plus papain and GDL (glucono-delta-lactone) plus K. varians FT4, was injected to the muscle at a pumping rate 15% w/v. The effect of these treatments on the proteolysis in the ham system was compared to a control ham, produced without starter culture and containing GDL acidulant to control pH and antibiotics to reduce the contribution of background microflora. Hydrolysis of sarcoplasmic and myofibrillar protein fractions was evaluated by SDS-PAGE and reverse phase-HPLC. Hams with different treatments were also investigated for differences in amino acid profile, protein and non-protein nitrogen level, colour, pH, water activity and moisture and microbiological evolution. There was no significant difference in the gross compositional analysis of any of the treatments compared to the control. There was no significant difference (p>0.05) in the protein content, non-protein nitrogen level, SDS-PAGE and free amino acid analysis between the control ham and ham inoculated with proteolytic starter culture. However, it was observed that hams containing starter cultures exhibited decreases in certain peptide fractions and corresponding increases in some free amino acids compared to the uninoculated control. It can be concluded that, while the principle mechanisms resulting in the proteolysis of this non-dried ham product involve the activity of endogeneous cathepsins, the addition of proteolytic starter cultures influence the amino acid profile thereby potentially enhancing the sensorial attributes of the ham.     

Qualitative effects of fresh and dried plum ingredients on vacuum-packaged,sliced hams

Boneless ham muscles (Semimembranosus + Adductor) were injected (20% w/w) with a curing brine containing no plum ingredient (control), fresh plum juice concentrate (FP), dried plum juice concentrate (DP), or spray dried plum powder (PP) at 2.5% or 5%. Hams were cooked, vacuum-packaged, stored at <4 °C and evaluated at 2-week intervals over 10 week. Evaluations were performed on sliced product to determine cook loss, vacuum-package purge, Allo–Kramer shear force, 2-thiobarbituric acid-reactive substances (TBARS), proximate analysis, objective color, sensory panel color and sensory attributes. FP, DP and 2.5% PP increased (P < 0.05) cook loss by 2% to 7% depending on treatment and level, but the highest cook loss (17.7%) was observed in hams with 5% PP. Shear force values increased as the level of plum ingredient increased (P < 0.05) from 2.5% to 5%, and the highest shear values were observed in hams containing 5% FP. There were no differences (P > 0.05) in lipid oxidation among treatments as determined by TBARS and sensory evaluation. FP and PP ham color was similar to the control, but DP had a more intense atypical color of cured ham. Minimal changes in physical, chemical and sensory properties were observed during storage of all treatments.     

Thermal and photochemical degradation of myoglobin pigments in relation to colour stability of sliced dry-cured Parma ham and sliced dry-cured ham produced with nitrite salt

Lipophilic and hydrophilic extracts of the red pigments from Parma ham and nitrosylated pigment of dry-cured ham produced with nitrite salt were prepared with acetone/water (75/25 v/v %) solution and aqueous phosphate buffer, respectively. The spectral characteristics differed for both the lipophilic and the hydrophilic Parma ham pigment compared with the dry-cured ham produced with nitrite salt. The red lipophilic pigment(s) extractable from Parma ham was(were) found to be very stable towards thermal degradation in acetone/water (75/25 v/v %) solution for temperatures up to 70 °C in contrast to the lipophilic pigment(s) extractable from dry-cured ham produced with nitrite salt, which was(were) found to have an energy of activation of 99 kJ/mol for thermal degradation. In contrast, quantum yields for photodegradation of the lipophilic ham pigments exposed to 366 nm (420 nm) monochromatic light were larger for Parma ham than for nitrite-cured ham [1.6×10^–5 (6.9×10^–6) versus 1.6×10^–6 (2×10^–6) mol einstein^–1] as determined for acetone/water (75/25 v/v %) solution. In agreement with these findings for the extracted lipophilic pigments, sliced Parma ham showed better colour stability than sliced dry-cured ham produced with nitrite salt, when stored in the dark at low oxygen concentration, in contrast to a faster initial discolouration for Parma ham when exposed to light, as shown for chilled storage for 35 days under retail conditions for the two products each packed at two oxygen levels (0.4 and 21%).     

射频等离子体活性水处理对火腿发色的影响

探讨射频等离子体活性水（radio frequency plasma activated water,RF-PAW）处理对肌红蛋白颜色及火腿发色的影响,对比亚硝酸钠溶液与RF-PAW的发色效果以及这2 种发色剂用于火腿发色后亚硝酸盐的残留量。结果表明,等离子体处理6 min以内得到的PAW,不会对高铁肌红蛋白（metmyoglobin,metMb）的颜色产生显著影响,会使氧合肌红蛋白逐渐氧化成metMb,颜色由鲜红色变为红棕色;肉眼观察发现,采用RF-PAW、亚硝酸盐溶液（nitrite,NI）作为亚硝酸盐来源来腌制火腿,都能使新鲜猪肉发色,且RF-PAW腌制的火腿发色效果更好,RF-PAW中的活性物质并未对火腿发色造成不良影响;色差分析结果显示,PAW腌制出的火腿有更高的a*、C*值以及更低的b*值,色素含量测定显示,PAW处理的火腿具有更高的亚硝化肌红蛋白色素百分比（43.52%）,说明PAW腌制比NI腌制形成更多的亚硝化肌红蛋白色素,使火腿的红色更深;通过亚硝酸盐残留测定发现,NI腌制的火腿亚硝酸盐残留量为54.45 mg/kg,而PAW腌制的火腿亚硝酸盐残留量为52.79 mg/kg,均小于国标限量值70 mg/kg。该研究结果为肉品低温等离子体保鲜与腌制技术的工程化应用提供理论基础和科学指导。     

新型发酵火腿色泽的影响因素优化

色泽是评价火腿质量的一项重要指标。以色泽或感官评价为考察指标,采用响应面法,探讨了腌制剂对新型发酵火腿切片色泽的影响。结果表明:最佳的亚硝酸钠的添加量0.01%、Vc的添加量0.03%、食盐的添加量2.37%;此时发酵火腿的切片色泽及感官评价最好。     

PROPERTIES OF DRY-CURED HAM: TEMPERATURE AND pH INFLUENCE DURING SALTING STAGE

The influence of pH and temperature upon color properties, during the salting stage of 11 days for the dry-cured ham process was studied. Semimembranosus, Semitendinosus and Biceps femoris muscles were studied and each muscle was divided in three sections (outer, middle and inner). The parameters under study were: moisture, salt concentration, residual nitrite level, CIELAB and reflectance ratio (R650/R570). Neither temperature nor pH affected any parameter analyzed (P>0.05). Only Semimembranosus (and its outer zone) showed differences (P < 0.05) for moisture and salt concentration. A concentration gradient between muscles and Semimembranosus zones was found for residual nitrite level. Lightness, yellowness and chroma showed differences (P<0.01) for Semimembranosus muscle and its outer zone. Redness and reflectance ratio R650/R570 were not different (P>0.05) between muscles and zones. Only the Semimembranosus muscle was different (P<0.01) for hue. Semimembranosus and Biceps femoris zones were different (P<0.01 and P<0.05 respectively) for this parameter.     

Effect of irradiation on the quality of turkey ham during storage

Effect of electron-beam irradiation on the quality of ready-to-eat (RTE) turkey ham was studied. Turkey hams were purchased from local stores and sliced into 0.5 cm-thick pieces and vacuum packaged. The ham samples were randomly separated into three groups and irradiated at 0, 1, or 2 kGy, and stored at 4?°C for up to 14 days. Volatiles, color, TBARS values and sensory characteristics were determined to compare the effect of irradiation and storage on the quality of RTE turkey ham. Irradiation had little effects on color and TBARS values of RTE turkey hams. Sensory analysis indicated that sulfury odor increased as irradiation dose increased, and the contents of sulfur compounds in irradiated RTE turkey hams were higher (P <0.05) than those in nonirradiated samples. Irradiation increased (P <0.05) the production of acetaldehyde, which could be related to a metal-like flavor in irradiated hams. However, overall quality changes in RTE turkey hams by irradiation up to 2 kGy were minor.