低盐干腌火腿的加工

干腌火腿风味独特,深受消费者青睐,但传统干腌火腿含盐量高,对其消费量和食用者健康均有不利影响。本文从火腿的成熟机理出发,综述了低盐干腌火腿的研究近况,指出低盐干腌火腿加工应注意的问题。     

涂膜制作低盐干腌火腿的研究

传统干腌火腿的盐分含量为9％～12％，生产周期长达6个月以上。本项研究，将新鲜猪腿肉去皮、去骨和切块后进行干腌，腌肉块经防腐涂膜处理后进行干燥和发酵，可以制成块状低盐干腌火腿，盐分含量降低到5％～7％，生产周期缩短到1个月，与传统工艺制作的干腌火腿的风味和口感相同。     

国外的干腌火腿

介绍国外著名的干腌火腿，乡村火腿、伊比利亚火腿、巴马火腿和西发里亚火腿的特点和加工工艺。     

干腌火腿低盐腌制强化高温发酵成熟工艺优化

以新鲜杂交猪后腿为原料,发酵成熟温度、腌制用盐量、后熟时间、氯化钾替代比例为考察因素,采用正交试验优化火腿现代发酵成熟工艺,并分析加工工艺对其脂质氧化及感官品质的影响。结果表明:火腿在发酵成熟过程中4个工艺因子均对其脂肪氧化和总体感官均有显著影响(P0.01),氯化钾替代比例及腌制用盐量为影响感官的主要因素。通过正交试验优化后火腿的加工工艺为用盐量6.5%、氯化钾替代比例30%,采用12~13℃发酵10 d后于14~18、19~28、29~34℃分别发酵15 d,再于35~37℃后熟45 d。     

干腌火腿的质量品质及研究现状

干腌火腿具有色泽鲜艳、香气浓郁、滋味鲜美、外形美观、保存期长等特色,是传统腌腊肉制品中的精华。文章系统阐述了衡量干腌火腿质量的品质指标、品质形成机理及干腌火腿的研究热点,以期为干腌火腿的质量评定及进一步研究提供借鉴。     

高品质干腌火腿关键加工技术

综述了传统干腌火腿的加工工艺特征,分析了传统干腌火腿加工的原理及关键加工工艺.提出了生产高品质干腌火腿的现代化加工方法.     

干腌火腿加工中脂类物质变化研究

干腌火腿加工中，脂类物质经过降解(脂解和氧化)作用，形成了大量的挥发性风味物质，这些物质对干腌火腿的最终风味起了决定性的作用。综述了干腌火腿加工中脂类物质的降解过程。     

中式干腌火腿现状与现代化加工技术实践——以金华火腿为例

介绍了中国著名中式干腌火腿(金华火腿、如皋火腿、宣威火腿、恩施火腿等品种)的发展历史、基本特征、传统加工工艺与特色;以金华火腿为例,分析了传统火腿加工的工艺特点及局限性,阐述了中式干腌火腿现代化加工技术的优势,生产项目工艺参数、关键技术和投资方案,为中式干腌火腿的现代化加工技术发展路径提供理论参考。     

低盐去骨块状火腿的研究

研究采用注射法腌制生产低盐块状火腿,生产周期可控制在40d左右,成品含盐量控制在5%-6%之间。并通过正交实验确定了复合抑菌剂优化配比为Nisin0.2g/kg,亚硝酸钠40mg/kg,抗坏血酸0.02%。通过感官及理化检测, 新工艺与传统工艺制作的火腿品质相似。      

低盐去骨块状火腿的研究

研究采用注射法腌制生产低盐块状火腿,生产周期可控制在40d左右,成品含盐量控制在5%-6%之间。并通过正交实验确定了复合抑菌剂优化配比为Nisin0.2g/kg,亚硝酸钠40mg/kg,抗坏血酸0.02%。通过感官及理化检测, 新工艺与传统工艺制作的火腿品质相似。     

干腌火腿研究

新鲜腿肉经切块、干腌、干燥和发酵制成块状干腌火腿。肉块盐分含量小于9%,发酵时腐败变质;肉块盐分含量大于15.5%,发酵后不会腐败变质,但也不会产生火腿香气;肉块盐分含量10%～13%,水分含量42%～48%,发酵后不发生腐败变质并可产生火腿香气。发酵时腐败变质的肉块具有较高的pH和很高的挥发性盐基氮含量;不腐败又不产生香气的肉块具有较低的pH和很低的挥发性盐基氮含量;不腐败并产生火腿香气的肉块具有适中的pH和适中的挥发性盐基氮含量。     

Lipolysis in dry-cured ham maturation

Thirty light Parma hams were tested for muscle lipolytic activity (acid and neutral lipase activity) and free fatty acid (FFA) amounts in M. semimembranosus and biceps femoris, during progressive phases (0, 3, 6, 10 months) of dry-cured ham manufacturing. No correlation was found between the activities of acid and neutral lipases in fresh M. semimembranosus, while during processing the activities were positively related (p<0.1), probably due to effects of muscle composition changes on lipolytic activities. In each processing step tested, acid lipase activities were higher in the M. semimembranosus than in the M. biceps femoris, and FFA amounts varied accordingly, the only exception being for the very dehydrated 10-month old M. semimembranosus, which yielded lower FFA than in the corresponding M. biceps femoris. FFAs in the end product correlated positively with acid and neutral lipase activities of green ham, suggesting that FFA production could be influenced by both raw meat properties and muscle composition during processing.     

低盐嫩化牛干巴与传统牛干巴的品质比较

对采用中心组合设计优化的最佳实验组与传统牛干巴的品质进行比较,结果显示:最佳实验组肌原纤维小片化指数(MFI)、综合感官品分值高于传统组,剪切力、Na+浓度低于传统组(p<0.05)。筛选的低盐和嫰化技术对降低传统牛干巴的盐含量,提高肉的嫩度是有效的。     

Factors affecting dry-cured ham consumer acceptability

The objectives of the present study were (1) to compare the relative importance of price, processing time, texture and intramuscular fat in purchase intention of dry-cured ham through conjoint analysis, (2) to evaluate the effect of dry-cured ham appearance on consumer expectations, and (3) to describe the consumer sensory preferences of dry-cured ham using external preference mapping. Texture and processing time influenced the consumer preferences in conjoint analysis. Red colour intensity, colour uniformity, external fat and white film presence/absence influenced consumer expectations. The consumer disliked hams with bitter and metallic flavour and with excessive saltiness and piquantness. Differences between expected and experienced acceptability were found, which indicates that the visual preference of consumers does not allow them to select a dry-cured ham that satisfies their sensory preferences of flavour and texture.     

Lipid and cholesterol oxidation products in dry-cured ham

An investigation was carried out on oxidative processes in dry-cured hams. Sixteen hams of various ageing times were divided into lean and fat parts, simulating typical consumer habits. All samples underwent analysis of peroxide value (PV), rancidity index (TBARs), 5 cholesterol oxidation products (COPs) and, in the lean samples, proximate composition. While the lean part was rather unaffected by oxidation, the external fat contained some of COPs, TBARs and PV. Comparison of hams at different ageing times revealed that lipid oxidation was substantially unaffected by the time of processing. It is concluded that good manufacturing practice will generally prevent oxidative damage in the edible part of dried hams, even if very long ageing times are used.     

Penicillium populations in dry-cured ham manufacturing plants

Seven ham manufacturing plants were sampled for 1 year to assess the mycoflora present in the air and on hams, with special attention given to potential mycotoxin producers. Temperature and relative humidity were recorded in the ripening rooms. Maturing rooms held hams from 2 to 3 through 6 to 7 ripening months, and aging rooms held hams for the following 6 to 7 months, until the 14-month ripening point, when they were ready for the market. Mean temperatures and relative humidities registered during the study were 14.9 degrees C and 62.4%, respectively, in maturing rooms and 16.3 degrees C and 57.6% in aging rooms. Aspergilli and penicillia, potential mycotoxin producers, were isolated in all the plants from the air and the ham. Aspergilli represented 5% of the isolates, while penicillia were largely dominant, with Penicillium nalgiovense being the most represented species (around 60% of the penicillia), followed by Penicillium nordicum, with 10 and 26% of the penicillia isolated, respectively, from the air or the ham. Ochratoxin A production ability, checked in vitro at 250C, was observed in 50% of the P. nordicum isolates obtained both from the air and the ham. Air and ham surface contamination by penicillia was greater in the ripening rooms, where higher temperatures were registered. A certain correlation was also observed between air and ham surface contamination. On the basis of this study, P. nordicum, the ochratoxin A producer that is notable on proteinaceous substrates, is normally present in ham manufacturing plants in Italy, even though not a dominant species. Further studies are necessary to clarify and ensure if dry-curing conditions minimize the potential risk of ochratoxin A formation in the product.     

Optimization of instrumental colour analysis in dry-cured ham

Colour of dry cured ham was measured by instrumental techniques in order to determine the optimum measurement index. Five different colour systems were used: CIE L(?)a(?)b(?), Hunter Lab, CIE L(?)u(?)v(?), xyY and XYZ, each with illuminants D65, C and A, and with both 10 and 2° observer angles. Measurements were taken in both Semimembranosus (SM) and Biceps femoris (BF) muscles. Hunter Lab system with illuminant A gave the most reproducible results within muscles for the three colour parameters evaluated. A further comparison of results obtained with 10 and 2° observer angles of Hunter Lab with illuminant A showed there were no significant differences between the angles. Significant differences between results from SM and BF muscles were found in all the hams, the BF always showing higher values than SM for every colour parameter.     

Beliefs and attitudes of butchers and consumers towards dry-cured ham

The objectives were to evaluate the attitude of butcher and consumer towards soft and pasty texture problems in dry-cured ham and to assess the butcher and consumer behaviour when selecting and purchasing this product. Ninety-nine butchers and 200 consumers were interviewed with 17-question and 20-question surveys, respectively. The texture problems (softness and pastiness) were highly important for both butchers and consumers. The characteristics most frequently considered “important” or “very important” by butchers were processing time, smell/aroma and texture as selection criteria and salty taste and aged/matured flavour as sensory indicators of dry-cured ham quality. According to butchers’ opinion, salty taste and their own advice are the factors most frequently considered “important” or “very important” as affecting the consumer’s decision to purchase. For the consumer, the sensory attributes were considered more important than extrinsic characteristics when purchasing dry-cured ham.     

Relationship between pH before salting and dry-cured ham quality

The effect of pH before salting on pork quality was studied in two sets of experiments: 904 hams, set A; and 104 hams, set B; the latter was used to verify the results from A. After pH measurements, the hams were subjected to the traditional process for producing Spanish dry-cured ham and then evaluated by an expert panel to correlate the sensory characteristics to the pH measurement before salting. The parameters evaluated were pastiness, softness, anomalous cut colour, crusting and white spots. Moisture, non-protein nitrogen, salt, protein, nitrate and nitrite were determined in samples from both experiments. The results obtained in experiment A showed that pastiness is closely related to the pH before salting (p<0.001), but not softness. From the receiver operating characteristics curve, a cut-off point of pH of 5.55 was selected to classify the raw material in two groups: normal-pH and low-pH hams. The pH before salting can also be correlated with the appearance of anomalous cut colour and crusting in hams. White spots were absent in both pH groups. Regarding compositional parameters, there were significant differences in moisture (p<0.001), salt (p<0.001), protein (p<0.001), non-protein nitrogen (p<0.001) and nitrate (p<0.05) contents between low-pH and normal-pH hams. The results from experiment B, confirmed the relationship between pH before salting and the appearance of defective texture and colour in the final product. Also results from experiment B confirmed the compositional parameters found in experiment A. Thus, the pH before salting is a good predictor for meat quality allowing the classification of the raw material in the first stage of manufacture. After classification, some modifications to the processing can improve the final characteristics of dry-cured hams.