Recent Advances in Food Processing Using High Hydrostatic Pressure Technology

High hydrostatic pressure is an emerging non-thermal technology that can achieve the same standards of food safety as those of heat pasteurization and meet consumer requirements for fresher tasting, minimally processed foods. Applying high-pressure processing can inactivate pathogenic and spoilage microorganisms and enzymes, as well as modify structures with little or no effects on the nutritional and sensory quality of foods. The U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) have approved the use of high-pressure processing (HPP), which is a reliable technological alternative to conventional heat pasteurization in food-processing procedures. This paper presents the current applications of HPP in processing fruits, vegetables, meats, seafood, dairy, and egg products; such applications include the combination of pressure and biopreservation to generate specific characteristics in certain products. In addition, this paper describes recent findings on the microbiological, chemical, and molecular aspects of HPP technology used in commercial and research applications.     

食品在高压静电场中冻结、解冻的实验研究

微能源在食品工业中的应用日益广泛,本文以马铃薯为研究对象,研究了不同场强对食品冻结,解冻过程和解冻后质量的影响,主要考察冻结曲线,解冻曲线、质地特性,液汁流失几方面。研究发现高压直流电场场强对马铃薯冻结过程,及其以后的无电场解冻过程,冻结食品在电场下解冻过程都有很大影响。不同场强对马铃薯解冻后的质地特性、液汁流失影响较小。     

我国食品超高压技术的研究进展

超高压技术是目前食品科学与工程技术领域的研究热点之一,是一种重要的非热加工技术,受到广泛关注。本文系统整理了1990—2012年国内学者有关超高压技术的1 030篇文章和167项专利,总结了国内超高压技术20余年发展历程以及6个主要研究方向。在此基础上,分析了国内目前研究存在的四大主要问题,提出未来研究的重点和方向,以期为国内超高压技术的研究与产业化应用提供参考。     

超高压技术在食品工业中的应用及前景

超高压技术作为一种食品加工技术的兴起主要是因为人们对新颖的食品储存技术的兴趣.应用超高压技术加工食品能使食品中酶的活性降低、杀灭微生物、改变食品组分间的相互作用等.本文综述了超高压设备的特点、超高压技术在食品工业中的应用现状以及存在问题等,并展望了超高压技术在食品工业中的应用前景.     

超高压加工技术在食品工业中应用的研究进展

食品超高压处理是一种非热加工技术,通过对整个食品的快速、均匀加压达到对食品杀菌、保藏、改性等目的.与其他处理方式相比,超高压处理具有加工过程污染低、营养物质损失少、风味保持度好等优点.本文通过研究国内外相关文献,主要从超高压加工技术的机理及在食品工业中的应用,包括杀菌、蛋白质改性、贝类脱壳、物质提取等方面综述了食品超高...     

High Pressure Destruction Kinetics of Clostridium Sporogenes Spores in Salmon Slurry at Elevated Temperatures

Salmon slurry containing C. sporogenes spores was subjected to high pressure (HP) treatments (700–900 MPa; 80–100°C, and 0–24 min). Destruction rates (D value) and pressure/temperature sensitivity parameters (Z_P and Z_T ) were evaluated. Thermal treatment D values were an order of magnitude higher than those under HP. Higher pressures and temperatures accelerated the spore destruction rates. Z_P values were 14.5, 17.3 and 15.5°C at 700, 800 and 900 MPa respectively, while Z_T values (at constant temperature) were 440, 540, 550 MPa at 80, 90, and 100°C, respectively. The z value under thermal treatment was 8.8°C. The spores were relatively more sensitive to temperature than to pressure.     

高压技术在食品工业中的应用研究

研究了常温下高压对不同食品素材的处理情况。从对微生物、维生素、酶、感官等几方面的影响来综合评定高压处理的效果。针对不同的素材设计了不同的处理方法。试验表明，果汁和蔬菜汁经高压处理后可以达到杀菌效果，而且Vc损失很少，残存酶活只有4％，色香味等感官指标不变．其综合效果明显优于热杀菌。动物性食品也能达到杀菌效果，并且产生了前所未有的愉快而独特的风味。     

超高压处理抑制低温烟熏火腿中的优势腐败菌

研究尝试应用微生物菌体总RNA提取代替DNA提取,进而通过反转录-PCR( RT-PCR),结合变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)技术,以期揭示超高压处理后低温烟熏火腿中腐败微生物的存活情况,探索RNA-DGGE手段判定超高压处理后微生物存活状态的可行性.分别以400 MPa和600 MPa的压力在室温(22℃)条件下,对包装后的烟熏火腿进行10 min超高压处理,未经高压处理样品作对照,于4℃冷藏条件下,贮藏1、15、30、60、90 d,直接提取样品中微生物的总RNA,对其进行RT-PCR和DGGE指纹图谱分析.DGGE指纹图谱显示,超高压处理对烟熏火腿中的优势腐败菌具有较强的抑制作用,且随压力的升高抑菌效应增强;超高压处理后烟熏火腿微生物种群结构变得单一,Weissella viridescens和Leuconostoc mesenteroides是超高压处理后烟熏火腿中的优势腐败菌.基于菌体总RNA提取的DGGE手段能够有效检测超高压处理后微生物的存活状况,揭示超高压对低温烟熏火腿中优势腐败微生物的抑菌效果.     

超高压处理对冷藏鲍鱼保鲜效果与品质变化的影响

本文以鲍鱼为材料,研究了超高压处理对鲍鱼体内微生物的消减作用和不同压力超高压处理后的鲍鱼在冷藏过程中挥发性盐基氮值、p H、脂肪氧化值、肌肉组织与硬度的变化情况,对比了热加工和超高压处理对鲍鱼品质变化的影响。研究结果显示,超高压具有良好的杀菌效果,鲍鱼经400 MPa和500 MPa处理10 min,体内菌落总数达到未检出状态,贮藏20 d后,仍符合生食标准。超高压处理能有效抑制鲍鱼挥发性盐基氮的产生,在4℃条件下保存30 d后TVB-N值仍小于35 mg/100 g。经超高压处理后的鲍鱼p H显著高于未加工鲍鱼,但4℃贮藏30 d后,超高压处理后的鲍鱼p H反而显著低于未加工鲍鱼;相比热加工和未加工的对照条件,超高压处理能延迟TBA值的升高,抑制脂肪氧化;组织切片和质构实验发现经超高压处理的鲍鱼肌肉纤维凝聚,肉质硬度升高,但随着贮藏时间的延长,硬度逐渐下降。结果表明,鲍鱼经400 MPa压力处理10 min,冷藏20 d后仍可生食,同时品质得到良好的提升。      

超高压和高温短时杀菌对樱桃汁品质的影响

比较了超高压(high pressure processing,HPP,550 MPa/2 min)和高温短时(high temperature short time,HTST,95 ℃/15 s)杀菌对樱桃汁中微生物、总酚、维生素C、花色苷、抗氧化能力以及感官品质的影响,并分析了4 ℃贮藏樱桃汁品质变化。结果表明:樱桃汁经过HPP和HTST杀菌后细菌总数小于100 CFU/mL、霉菌和酵母菌未检出,两者对樱桃汁均具有较好的杀菌效果;两种方式杀菌后樱桃汁中绿原酸和矢车菊素-3-芸香糖苷含量显著降低(p<0.05),HPP樱桃汁中绿原酸与矢车菊素-3-芸香糖苷保留率分别为95.4%±8.0%和77.7%±13.8%,显著高于HTST樱桃汁(p<0.05)。HPP对樱桃汁果胶、总酚、维生素C、天竺葵素-3,5二葡萄糖苷含量无影响,儿茶酚含量提高了4.6%;HTST降低了樱桃汁果胶、总酚、儿茶酚、维生素C、天竺葵素-3,5二葡萄糖苷的含量;两种果汁抗氧化能力无显著变化(p>0.05)。HPP樱桃汁在香气、滋味、颜色方面比HTST樱桃汁具有更好的感官品质。4 ℃冷藏期间,两种樱桃汁中细菌总数缓慢升高,但霉菌与酵母菌仍未检出;HPP樱桃汁中总酚、绿原酸、儿茶酚、维生素C、矢车菊素-3-芸香糖苷含量以及抗氧化能力均高于HTST樱桃汁。因此,HPP樱桃汁保持了更好的品质。     

超高压技术在水产品贮藏与加工中的应用研究进展

超高压技术以其独特的优势,在改善水产品理化、微生物及感官品质方面显示出了巨大潜力。超高压具杀菌、灭酶、抑制腐败物质生成及保持质地等效果,可改善贮藏期间水产品的感官品质、延长货架期。水产品脱壳、凝胶化及快速冷冻/解冻是超高压杀菌技术的延伸,是今后超高压技术在水产品贮藏与加工应用中的主要研究领域及发展方向,如何减轻或利用超高压引起的色变、熟化及脂肪氧化现象是超高压技术在水产品贮藏与加工应用中亟待解决的问题。     

Evaluation of High Pressure Processing as an Additional Hurdle to Control Listeria monocytogenes and Salmonella enterica in Low-Acid Fermented Sausages

Low‐acid fermented sausages (fuet and chorizo) were manufactured to evaluate the combined effect of high pressure processing (HPP) and ripening on foodborne pathogens. Raw sausages inoculated with a three‐strain cocktail of Salmonella ser. Derby, London, and Schwarzengrund, and a three‐strain cocktail of L. monocytogenes ser. 1/2 c and 4b were pressurized at 300 MPa for 10 min at 17 °C. Afterwards, sausages were ripened at 12 °C and 80% RH for 27 d. Salmonella counts decreased in all studied sausages during ripening. However, the application of HPP as an additional hurdle to the ripening process produced a greater decrease in the Salmonella population, showing lower counts (3 MPN/g) in ripened sausages. By contrast, lower values of L. monocytogenes counts were obtained in non‐treated (NT) than in pressurized sausages due to the delay of pH drop caused by HPP inactivation of endogenous lactic acid bacteria. After pressurization of raw sausages at 300 MPa, a discoloration of sausages was observed, coinciding with an increase in L* values.     

低温和中温协同超高压对鲜榨荔枝汁灭酶处理和色泽影响的研究

为探讨超高压处对鲜榨荔枝汁中过氧化物酶(POD)、多酚氧化酶(PPO)活性的影响,对鲜榨荔枝汁进行了单独超高压处理（300~450 MPa,10~40 min）及低温（10 ℃）、中温（40~70 ℃）协同超高压(450 MPa,20 min)处理,通过对荔枝汁品质指标测定,探讨了温度协同超高压对荔枝汁品质的影响。试验结果表明：在室温、保压时间为20 min的条件下,300~450 MPa压力范围内荔枝汁中POD酶被激活,在300 MPa时活性最高;PPO酶在此压力范围内则随着压力的升高而降低;POD比PPO酶更耐压;450 MPa压力条件下,随着保压时间的延长,POD、PPO酶的活性减小;低温和中温协同超高压处理对荔枝汁中POD、PPO酶的钝化存在一定的协同效应,且中温范围内（40~70 ℃）温度越高,协同抑制效应越明显;中温协同超高压处理后的荔枝汁的L*值显著升高,果汁的亮度增加,但是随着协同温度的升高,总色差ΔE*逐渐增大,果汁的色泽变化增大。     

Recent Advances in the Recovery and Improvement of Functional Proteins from Fish Processing By‐Products: Use of Protein Glycation as an Alternative Method

ABSTRACT: The recovery of proteins from fish by‐products for their utilization as food ingredients is becoming of increasing interest in the food industry as they may possess good functional and nutritional properties. This article reviews the main processing methods, such as enzymatic hydrolysis, pH shifting, membrane filtration, and some emerging technologies, used for the recovery of proteins from fish processing by‐products. The impact of these methods on the yield and, especially, on the functionality of the recovered proteins is discussed in detail. Considering that there is a huge amount of fish by‐products destined for nonfood use, one of the current challenges of the food industry is the development of technologies that allow the recovery of ingredients from the fish processing by‐products with potential to provide new and natural sources of high‐value functional ingredients for human consumption. In this sense, this review explores the potential use of the glycation reaction to increase the yield of proteins extracted from fish by‐products, as well as the effect of this reaction on their functional and biological properties.