Application of computer vision systems for estimation of fat content in poultry meat

The paper presents the possibility of use a computer vision system (CVS) for estimation fat content in poultry meat. The estimation of this ingredient content was made in the material obtained in industrial conditions. Chicken and turkey carcasses were selected randomly, from which the thigh muscles (from chickens and turkeys) and chicken breast muscles were taken. Analysis of correlation was made between content of white spots achieved with CVS method and fat content determined using the reference Soxhlet method. According to the achieved results, it was concluded that the computer vision system for images of turkey thigh muscles can be used to estimate its fat content.     

Factors Impacting the Formation of 3-MCPD Esters and Glycidyl Esters During Deep Fat Frying of Chicken Breast Meat

The effect of the frying temperature, frying duration and the addition of NaCl on the formation of 3‐monochloropropane‐1,2‐diol (3‐MCPD) esters and glycidyl esters (GE) in palm olein after deep frying was examined in this study. The eight frying systems were deep‐fat frying (at 160 and 180 °C) of chicken breast meat (CBM) (with 0, 1, 3 and 5% sodium chloride, NaCl) for 100 min/day for five consecutive days. All oil samples collected after each day were analyzed for 3‐MCPD ester, GE, and free fatty acid (FFA) contents, specific extinctions at 232 and 268 nm (K₂₃₂ and K₂₆₈), p‐anisidine value (pA), and fatty acid composition. There was a significant (p < 0.05) decrease in the 3‐MCPD esters and a significant (p < 0.05) decrease in the GE with the increasing of the frying duration. There were significant (p < 0.05) increases in the 3‐MCPD esters formed when the concentration of NaCl increased from 0 to 5%. The addition of NaCl to the CBM during deep frying had no significant effect on the GE generation. The FFA contents, K₂₃₂ and K₂₆₈ and pA showed that all the frying oils were within the safety limit.     

木质鸡胸肉生肉品质表征及检测方法研究

目的探索木质肉(woody/wooden breast,WB)生肉品质特性差异及客观检测方法。方法对不同木质鸡胸肉等级样本的重量、挤压力(CF Probe、CF TA-25)进行检测,同时在剪切实验中以剪切力(MORSF)、剪切做功(MORSE)及剪切峰值个数(PC-MORS)作为生肉质构分析指标。结果重量、CF Probe、CF TA-25、MORSF、MORSE、PC-MORS随着WB等级的递增而显著增大,2种硬度检测探头均可用于鸡胸肉的硬度检测。PC-MORS在MORSF和MORSE的基础上可有效区分WB等级,同时可显示鸡胸肉肌肉内部的层状结构信息。各测量指标之间存在不同程度的相关性,其中重量、CF Probe、MORSE、PC-MORS与WB等级之间存在极显著相关。建立的BP神经网络模型区分正常肉和木质肉的总体识别率达90.6%。结论本研究确定了木质鸡胸肉生肉硬度检测方法、质构分析的特征参数,并研究其木质化等级判定模型,研究结果可为后续木质鸡胸肉在线检测分级装置的研发提供一定的理论支撑。     

添加木质肉的鸡肉火腿肠品质特性分析

为探究木质肉(Woody breast,WB)添加量对鸡肉火腿肠品质特性的影响及其添加的可行性,以5种不同木质肉添加量的火腿肠为研究对象,对其质构、感官、水分分布及微观结构进行检测分析。结果表明:木质肉添加量维持在50%时,火腿肠弹性、回复性、粘聚性参量最优,均达到优级火腿肠评判标准,分别为0.83、0.29、0.71,其质地、感官总评最高,分别为1.67和4.50。低场核磁显示木质肉添加量为50%时,自由水占比最低,结合水占比最高,分别为2.99%和0.78%,不易流动水基本保持不变。火腿肠微观结构随着木质肉添加量的增加由完整、清晰、分布均匀变为多孔洞、蓬松状。研究表明,将木质肉以肉糜的状态加入火腿肠具有一定可行性,且添加适量的木质肉糜对优化火腿肠品质具有一定的作用。     

不同温度对调理鸡排低温贮藏品质特性的影响

为研究不同温度对调理鸡排低温贮藏品质特性的影响,本实验利用3 种不同的贮藏温度（4 ℃（冷藏）、－2 ℃（冰温贮藏）和－18 ℃（冷冻贮藏））对调理鸡排进行贮藏,并通过对贮藏期间调理鸡排菌落总数、颜色、持水力、质构特性等的测定以及扫描电子显微镜的观察,分析调理鸡排理化品质以及微观结构的变化情况。菌落总数分析结果表明,相比于冷藏,冰温贮藏可以将调理鸡排的货架期延长2 倍（从约4 d延长到约12 d）;理化品质分析结果表明,冰温贮藏条件下调理鸡排的持水力和质构特性都得到了更好的保持。此外,扫描电子显微镜的观察结果表明,冰温贮藏条件下鸡排的微观结构受到的损伤相较于冷藏和冻藏而言更小。虽然冷冻贮藏条件下鸡排的货架期较长（3 个月以上）,但是其持水力、质构、微观结构等品质下降也更快。而冰温贮藏在延长货架期的同时,也更好地保持了调理鸡排的品质特性。综上,本研究可为冰温贮藏在调理鸡排贮运过程中的应用提供理论参考。     

鱼油DHA脂质体的制备及稳定性

以鱼油二十二碳六烯酸（docosahexaenoic acid,DHA）为原料,分别采用薄膜分散法和薄膜分散法联合动态高压微射流技术（dynamic high pressure microfluidization,DHPM）制备鱼油DHA粗脂质体（crude liposomes-DHA,CLs-DHA）和纳米脂质体（nanoliposomes-DHA,NLs-DHA）。以平均粒径、多分散指数（polydispersity index,PDI）和Zeta电位为评价指标,考察CLs-DHA和NLs-DHA的pH值稳定性和贮藏稳定性。结果表明：随着pH值逐渐增大,CLs-DHA和NLs-DHA的平均粒径和PDI均呈下降趋势,Zeta电位绝对值逐渐升高,在pH 7.4时具有较好的稳定性,NLs-DHA变化相对小于CLs-DHA;在4 ℃贮藏95 d过程中,与NLs-DHA相比,CLs-DHA的平均粒径、PDI和Zeta电位变化幅度相对较大,可见NLs-DHA的稳定性优于CLs-DHA;差示扫描量热法分析结果也表明,适度的DHPM处理可增强脂质体的稳定性,NLs-DHA具有更好的稳定性。     

Recent developments in the applications of image processing techniques for food quality evaluation

Image processing techniques have been applied increasingly for food quality evaluation in recent years. This paper reviews recent advances in image processing techniques for food quality evaluation, which include charge coupled device camera, ultrasound, magnetic resonance imaging, computed tomography, and electrical tomography for image acquisition; pixel and local pre-processing approaches for image pre-processing; thresholding-based, gradient-based, region-based, and classification-based methods for image segmentation; size, shape, colour, and texture features for object measurement; and statistical, fuzzy logic, and neural network methods for classification. The promise of image processing techniques for food quality evaluation is demonstrated, and some issues which need to be resolved or investigated further to expedite the application of image processing technologies for food quality evaluation are also discussed.     

Recovery of used frying oils with adsorbent combinations: refrying and frequent oil replenishment

Treatment of used frying oils with adsorbent combinations may improve the quality of fried foods and extend the frying life of oil. Two selected combinations of four commonly used filter aids: Britesorb (Br), Hubersorb 600 (HB), Frypowder (Fr), and Magnesol (Ma) were used to recover used frying oils by vacuum filtration. The effectiveness of the adsorbent treatments were evaluated by refrying chicken fritters and breasts in the recovered used oil. After 32 h continuous frying, the parameters of treated oil subjected to adsorbent combinations F (3% HB+3% Ma+2% Fr) and B (2% HB+2% Ma+3% Br), were reduced as follows: 61.9 and 59.7%, 38.0 and 11.3%, 25.2 and 19.5%, and 9.4 and 3.5% for free fatty acids (FFA), total polar component (TPC), Foodoil Sensor (FOS) reading, and color differences (ΔE), respectively, compared to the untreated used oil. After daily treatment for 4 days, the filter aid combination F reduced the final values of FFA, TPC, FOS and color differences by 64.2, 19.1, 32.6 and 4.4%, respectively, compared to the untreated control. These adsorbent combinations may be useful in extending the life of frying oils.