浅渍法发酵豇豆的工艺优化

以具有降解亚硝酸盐功能的植物乳杆菌（Lactobacillus plantarum）SD-7和具有优良抗氧化能力的植物乳杆菌（Lactobacillus plantarum）FM-LP-9为复合发酵剂（1∶1），采用浅渍法发酵豇豆。以硬度和感官评分为考察指标，通过单因素试验及响应面试验研究复合发酵剂接种量、发酵温度和发酵时间对浅渍法发酵豇豆品质的影响。结果表明，最佳发酵工艺条件为发酵温度25 ℃，接种量5%，发酵时间125 h，在此优化条件下，得到的浅渍法发酵豇豆硬度为47.31 N，感官评分为90.98分，香气浓郁、口感脆嫩。     

Reduction of Boar Taint Compounds in Kraski prsut through Dry-curing Process

Given that surgical castration of male pigs could be abandoned, the problem of product acceptability can become critical in dry-cured hams, especially when raw material comes from conventional pig husbandry. In this study, we have investigated 16 thighs harvested from 8 entire male fatteners that were submitted to 15 months of dry-curing process. Skatole and androstenone were determined in subcutaneous fat before (n = 8) and post processing (n = 16). After 15 months of dry-curing, markedly lower fat tissue concentrations of androstenone (36%) and skatole (20%) were determined. The reduction was independent of the level of boar taint substances.     

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.     

Nutritional and sensory quality of porcine raw meat, cooked ham and dry-cured shoulder as affected by dietary enrichment with docosahexaenoic acid (DHA) and α-tocopheryl acetate

The effects of dietary enrichment of pig diets with DHA from a marine source (Algatrium^®) and α-tocopheryl acetate on the nutritional and sensory characteristics of pork and pork products were evaluated. Raw and cooked hams, and dry-cured shoulders from pigs fed with three diets (control, control supplemented with 0.3% DHA plus 50 ppm α-tocopheryl acetate and control with 200 ppm α-tocopheryl acetate) were used. The treatments did not cause any significant differences in proteolytic and antioxidant enzyme activities, except on catalase (CAT) which increased significantly in raw hams from pigs fed DHA supplemented diets. Vitamin E accumulated in samples with α-tocopheryl acetate supplementation. DHA added to the diet increased the DHA level by 87% compared with the control treatment in both raw and dry-cured shoulders, and exceeded 82% in cooked hams. In consequence, the incorporation of the n − 3 source in the diet significantly reduced the n − 6/n − 3 ratio in all products. The ratio reduction ranged from 51% in dry-cured shoulders to 65% in cooked and raw hams.     

Effect of ripening time and rearing system on amino acid-related flavour compounds of Iberian ham

The evolution of free amino acids and amino acid-derived volatile compounds during the ripening of Iberian ham from pigs reared in a Montanera system (outdoor-based, with acorn and pasture available) and a Pienso system (indoor-based, with a high oleic acid concentrate) was studied. Ripening time influenced significantly all the free amino acids detected (p < 0.05) except for threonine and tyrosine. The total free amino acid content increased significantly from day 120 to day 230 (drying stage) and then the concentration remained almost steady. This marked increase in the free amino acid content matched an increase in the amino acid-derived volatile compounds. The volatile compounds also increased after day 230. Conversely, rearing system had a weak effect on the free amino acid content and on the amino acid-derived volatile compounds. Only glutamic acid was significantly influenced (p = 0.027), and a slight effect on proline and aspartic acid was found (p = 0.051 and p = 0.084, respectively), concentrations being larger in Montanera hams than in Pienso ones. With regard to the amino acid derived volatile compounds, only a significant influence of rearing system on acetaldehyde and on the coelution of 2,6-dimethylpyrazine+dihidro-2(3H)furanone was found. The small differences caused by rearing system confirm the great importance of concentrate formulation.     

不同烹饪方式对干腌火腿理化、感官及风味品质的影响

熟肉制品的理化、感官和风味品质与烹饪方式密切相关,通过比较高压、微波、蒸制和煮制4 种烹饪方式对盘县火腿理化和营养特性、风味品质及感官评价的影响,筛选出最适宜盘县火腿的烹饪方法。结果表明：蒸制和煮制火腿色泽更好,pH值较高,分别为6.10和8.16,水分含量较高,分别为35.70%和35.20%,盐含量和烹饪损失率更低,分别为28.01%、5.15%和28.06%、4.99%;微波处理火腿粗脂肪和粗蛋白含量最高,分别为6.48%和55.14%;4 种烹饪方式均导致火腿中风味物质种类减少,但微波、蒸制和煮制可增加风味物质含量,特别是蒸制;聚类分析和Biplot分析同样显示出蒸制对原料火腿风味的改善作用;主成分分析结果表明,15 种特征香气成分中有7 种与蒸制火腿相关,包括2-甲基丁醛、3-甲基丁醛、己醛、壬醛、庚醛、辛醛和(E)-2-癸烯醛;感官评价结果表明,蒸制火腿的肉香属性得分最高,偏最小二乘回归相关性分析显示,这可能与其高含量的3-甲基丁醛、己醛和壬醛有关。盘县火腿最佳烹饪方式为蒸制,有助于改善其理化特性和风味品质。     

盘县火腿自然发酵过程中理化和风味特征

分析盘县火腿自然发酵过程中理化特性和风味特征的变化,并结合香气活度值（odor activity value,OAV）和偏最小二乘回归（partial least squares regression,PLSR）分析确定盘县火腿主体香气成分。结果表明：盘县火腿理化特性在发酵过程中发生显著变化（P＜0.05）,pH值和NaCl含量显著上升,而水分活度、水分含量和肌内脂肪含量显著下降,亮度值和黄度值呈持续下降趋势,而红度值先降低后升高;随着发酵的进行,盘县火腿中风味物质的种类从25 种增加至40 种,含量从（218.50±22.14） μg/kg上升至（1 044.49±51.47） μg/kg,其中醛类物质的种类和含量最丰富;OAV分析筛选出16 种主体香气物质,PLSR模型显示3-甲基丁醛、十二醛、十六醛、(Z)-9-十八烯醛和十八醛对盘县火腿肉香、清香和油脂香有显著贡献。