Comparison study of chitosan,EDTA, eugenol and peppermint oil for antioxidant and antimicrobial potentials in chicken noodles and their effect on colour and oxidative stability at ambient temperature storage

The aim of this study was to investigate the antioxidant and antimicrobial activity of chitosan, EDTA, eugenol and peppermint essential oil and their effect on color and oxidative stability of chicken noodles stored at 35 ± 2 °C. Results indicated that among the four preservatives, eugenol treatment exhibited higher ABTS⁺ (2-2-azinobis-3ethylbenthiazoline-6-sulphonic acid) radical cation activity (89.54%), DPPH (1, 1-diphenyl-2-picrylhydrazil) (51.30%) and superoxide anion scavenging activity (66.82%). Total polyphenol content was also higher in eugenol treated samples. The samples treated with eugenol and chitosan protect against an increase lightness (L-value) and decrease in redness (a) and yellowness (b) values during storage. However, pH value was highest in noodles with chitosan treatment while TBARS (2-thiobarbituric acid reacting substances) and FFA (Free fatty acids) contents were lowest in noodles with eugenol irrespective of storage periods. Eugenol treatment also showed positive impact on microbiological quality and sensory attributes. In conclusion, eugenol has more potential as a natural preservative to increase shelf-life of chicken noodles.     

Bacterial growth on chicken eggs in various storage environments

An evaluation of the effects of various storage and transport conditions on the bacterial growth associated with chicken eggs that are usually transported without temperature control was done. Chicken egg samples were randomly collected from a layer management system that employs a fully automated environmental control unit. These eggs were subjected to temperature shocks to simulate various transport and storage conditions. The results show that a 4-h low temperature shock is the most effective condition for limiting organism growth in or on eggs. Much higher organism counts were found in both the egg contents and on the eggshells, which had been subjected to high temperature shocks. It is finally recommended to the egg industry that incorporating a cold shock of 4 h and consequent storage at 25 °C will contribute to a longer egg shelf life and enhanced egg quality.     

Evaluation of ISO 10272:2006 standard versus alternative enrichment and plating combinations for enumeration and detection of Campylobacter in chicken meat

In the present study, we evaluate the recommended ISO 10272:2006 versus alternative procedures for Campylobacter enumeration and enrichment in naturally contaminated chicken meat samples (n = 49). Three enrichment media were evaluated; Bolton broth, Preston broth and CampyFood broth^® (bioMérieux SA, Marcy l’Etoile, France). In addition, three selective plating agars were compared; modified charcoal cefoperazone deoxycholate agar (mCCDA), CampyFood agar^® (CFA; bioMérieux SA) and Brilliance CampyCount agar^® (BCC; Oxoid, Basingstoke, England). Direct plating on CFA provided the highest number of Campylobacter positive samples (17/49); however this was not statistically different (P > 0.05) from numbers of positive samples recovered by direct plating on mCCDA (15/49) or BCC agars (14/49). Also, there was no significant difference between Campylobacter counts on the three compared media (P > 0.05). The coloured colonies of Campylobacter on CFA and BCC were easier to record and count than those on mCCDA. Enrichment of chicken meat samples in Bolton broth for 48 h and subsequent plating on CFA provided significantly higher (P < 0.05) Campylobacter detection compared to the other broth-agar combinations. Enrichment in Preston broth for 24 h followed by plating on mCCDA gave a higher number of positive samples (20/49) than 48 h enrichment in Bolton broth and plating on mCCDA (15/49). Enrichment in Bolton broth for 48 h followed by plating on CFA recovered 35% of samples below the limit for quantifications (<10 CFU/g, n = 34), as identified by direct plating on mCCDA. Compared to the current ISO method, some alternative combinations of enrichment and agar media could provide significantly better detection and enumeration of Campylobacter in chicken meat.     

Freezing and frozen storage of actomyosin from different species

A comparative study was made of the influence of freezing (–24°C) and frozen storage (–12°C) on the functional properties (viscosity, solubility) and physico-chemical characteristics (aliphatic and aromatic hydrophobicity, ATPase activity) of actomyosin (AM) from myosystems (chicken and hake) of differing freezing and frozen stability. The difference in functional behaviour between chicken and hake AM as a consequence of freezing and frozen storage suggests that, for hake AM, denaturation and aggregation occur essentially through direct aggregation of AM molecules to produce AM aggregates, whereas in chicken proteins, AM first dissociates into myosin and actin to produce myosin and myosin-actin aggregates.     

Antioxidant and antimicrobial effects of garlic in chicken sausage

The antioxidant and antimicrobial effects of equivalent concentrations of fresh garlic (FG), garlic powder (GP) and garlic oil (GO) were investigated against lipid oxidation and microbial growth in raw chicken sausage during storage at 3°C. The antioxidant activities were compared to that of a standard synthetic antioxidant; butylated hydroxyanisole (BHA). The initial mean levels of thiobarbituric acid (TBA) value and peroxide value (POV) were 0.140 and 6.32, respectively. However after 21 days of storage, TBA and POV ranged from 0.151 to 4.92, respectively, in FG (50 g/kg) formulated samples to 0.214 and 8.64, respectively, in GO (0.06 g/kg) formulation. Addition of either garlic or BHA (0.1 g/kg) significantly delayed lipid oxidation when compared with control. The antioxidant activities of the various materials added followed the order FG>GP>BHA>GO. On the other hand, the initial aerobic plate count (APC) in the samples was 4.41 log₁₀ CFU/g. Addition of FG (30 g/kg) or GP (9 g/kg) significantly reduced the APC and, subsequently, the shelf-life of the product was extended to 21 days. However, addition of GO or BHA resulted in no significant difference in APC when compared with control. Sensory analysis indicated that FG had a significant stronger flavor than the other sausage formulations. The results suggest that fresh garlic and garlic powder, through their combined antioxidant and antimicrobial effects, are potentially useful in preserving meat products.     

Possible role of volatile amines as quality-indicating metabolites in modified atmosphere-packaged chicken fillets: Correlation with microbiological and sensory attributes

The present work evaluated the possible role of volatile amines as indicator(s) of poultry meat spoilage. Fresh chicken meat (breast fillet) was packaged in four different atmospheres: air (A), vacuum (VP) and two modified atmospheres (MAs), namely M1, 30%/65%/5% (CO₂/N₂/O₂) and M2, 65%/30%/5% (CO₂/N₂/O₂). All chicken samples were kept under refrigeration (4 ± 0.5 °C) for a period of 15 days. Of the four treatments, the VP and M1 and M2 gas mixtures were the most effective for delaying the development of aerobic spoilage microbial flora. Pseudomonas spp. in chicken samples stored under M2 gas mixture and VP were significantly lower than all the other samples after 15 days of storage. Of the remaining bacterial species examined, lactic acid bacteria (LAB), Brochothrix thermosphacta, were dominant in the microbial association of both aerobically- and MA-packaged chicken, while yeasts contributed to a much lesser extent in the final microbial flora of chicken meat. On the basis of microbiological data (TVC), shelf-life extensions of 2, 4 and 9–10 days were achieved by VP and M1 and M2 gas mixtures. Results of the present work showed that the limit of sensory acceptability (a score of 6) was reached for the aerobically, vacuum-packaged and M1 gas mixture chicken samples approximately on days 6–7 and 9–10, respectively. Based on sensory (taste) analysis and with regard to chicken spoilage and freshness, TMA-N and TVB-N limit values of acceptability, namely 10.0 mg N/100 g and 40 mg N/100 g for chicken samples stored in air, may be proposed as the upper limit values for spoilage initiation of fresh chicken meat stored aerobically. Interestingly, the M2 gas mixture sample did not reach these limit values throughout the 15 day storage period. The formation of volatile amines during chill storage of chicken meat, under the packaging conditions examined in the present study, seemed to be in good agreement with the increase in microbiological count (TVC) and sensory taste score except for the M2 gas mixture.     

Encapsulated phosphates reduce lipid oxidation in both ground chicken and ground beef during raw and cooked meat storage with some influence on color,pH, and cooking loss

Effects of encapsulated sodium tripolyphosphate (STP), sodium hexametaphosphate (HMP) and sodium pyrophosphate (SPP) on lipid oxidation in uncooked (0, 2, 24 h) and cooked (0, 1, 7 d) ground chicken and beef during storage were determined. Ten phosphate treatments included a control (no phosphate), three unencapsulated (u) at 0.5% and three encapsulated (e) phosphates (0.5%) each at a low (e-low) and high (e-high) coating level. Two heating rates (slow, fast) were investigated. Cooking loss (CL), pH, color, orthophosphate (OP), TBARS and lipid hydroperoxides (LPO) were determined. A fast heating and uSTP resulted in lower CL (p < 0.05). Orthophosphate increased with phosphate incorporation, slow heating and storage (p < 0.05). Encapsulated phosphates and increased coating level reduced OP (p < 0.05). Unencapsulated STP increased CIE a* and pH, whereas uSPP decreased CIE a* and pH (p < 0.05). Encapsulated phosphates and the greater coating level had no effect on the pH in cooked samples. Not increased coating level but encapsulated phosphates decreased lipid oxidation in cooked samples (p < 0.05).     

姜蒜提取物对微波间歇处理麻辣鸡块的辅助保鲜作用

目的 研究微波间歇处理结合生姜、大蒜、姜蒜混合提取液对麻辣鸡块的最佳保鲜方法。方法 以麻辣鸡块贮藏过程中剪切力、弹性、硬度、水分含量、pH值、TBA值、NPN含量、TVB-N含量、菌落总数、感官评价为指标,分析比较生姜提取液（质量分数为5%）、大蒜提取液（质量分数为5%）、姜蒜混合提取液（质量分数为2.5%的生姜提取液+质量分数为2.5%的大蒜提取液）复合微波间歇处理（微波30 s,静置20 min,再微波30 s,微波频率为2450 MHz,微波功率密度为4 W/g）对麻辣鸡块的保鲜作用。结果 生姜、大蒜、姜蒜混合提取液均能抑制鸡肉微生物的生长、质构特性的变差,较好地维持其感官品质,其中大蒜处理组保鲜效果最好。在第36天,大蒜组鸡块的剪切力值和硬度值与对照组同比高出50.13%和81.59%,且能维持菌落总数低于4.455 lg(CFU/g),而对照组、生姜处理组麻辣鸡块均已腐败变质。结论 微波间歇处理复合质量分数为5%的大蒜提取液处理,在4 ℃贮藏条件下,真空包装麻辣鸡块的保质期可达36 d。     

微波肉食品开发的初步研究

选用鸡脯作为原料,采用混合配制盐、木瓜蛋白酶为主要嫩化手段,辅以其它风味添加剂,在温度0－5℃,时间24hr下掩制,并用微波作为成熟手段,从而获得嫩度、风味良好的方便食品。