热风联合真空微波膨化鸭胸肉工艺优化

以鸭胸肉为对象,优化真空微波膨化鸭胸肉的最佳工艺条件。采用单因素试验考察膨化前水分含量、微波强度、微波时间和真空度对膨化鸭胸肉体积收缩率、复水比、感官评分的影响,利用响应面试验优化热风联合真空微波膨化鸭胸肉的工艺条件。结果表明:膨化前水分含量、微波强度、微波时间和真空度对膨化鸭胸肉的品质均有一定影响。在固定真空度为0.08 MPa条件下,各因素对膨化鸭胸肉体积收缩率和感官评分的影响程度大小顺序均为微波强度微波时间膨化前水分含量,通过等高线叠加法确定最佳膨化鸭胸肉加工工艺参数范围:膨化前水分含量为59%~63%,微波强度为20.5~24.7 W/g,微波时间为6.1~6.6 min。在此条件下,膨化鸭胸肉的体积收缩率可低于34%,感官评分在4.75以上,研究结果可为鸭肉膨化食品工业化生产提供理论参考。     

Optimising microwave vacuum puffing for blue honeysuckle snacks

Fresh blue honeysuckle fruit slices were puffed in a microwave vacuum dryer up to a final moisture content about 5% (w.b.). The effect of initial moisture content (IMC) (25–45%), vacuum pressure (VP) (70–90 kPa) and microwave intensity (MI) (10–30 W g^?1) on quality attributes, in terms of expansion ratio (ER), hardness (HD), crispness (CR) and colour of the products, were analysed by response surface methodology. Besides the effect of MI on chroma (CH), the high IMC and low VP had a significantly positive impact on the quality attributes of blue honeysuckle snacks. The optimum product qualities, which were ER (1.62 times), HD (5836.31 g), CR (4.48), and CH (28.7) were obtained at an IMC of 38.42%, VP of 82.02 kPa, and MI of 22.42 W g^?1. The microwave vacuum method has obvious advantages when puffing the blue honeysuckle snacks.     

Effect of puffing conditions on physical properties and rehydration characteristic of instant rice product

The aim of this work was to study the effects of puffing conditions on the properties of instant rice and to obtain optimal processing condition for product with rehydration time within 5 min. Thai jasmine rice was soaked, cooked and dried at 80 °C in a tray dryer before being puffed at different moisture contents (15–20% wb), temperatures (200–220 °C) and time intervals (20–30 s). The rice puffed at higher moisture contents and puffing temperatures for longer time exhibited higher volume expansion ratios and shorter rehydration times. Presumably, case hardening of the grain surface occurred. Instant rice that can be rehydrated in 5 min with more acceptable hardness than the commercial instant rice was obtained. Regression models to predict the quality of instant rice were developed using response surface methodology.     

Understanding puffing in a domestic microwave oven

This work is intended to develop an overall understanding of puffing of a starch-based snack in a home microwave oven, using primarily the microwave energy. Combination of experimental measurements was used, including dynamic mechanical thermal analysis, CT-Scan, SEM, image processing, and measurement of temperature, moisture content, and expansion ratio. Effects of various product and process parameters on puffing, including those of pretreatment to produce the half product, were studied. Experimental data showed that the physicochemical processes contributing to crust formation were gelatinization of starch, migration of soluble ingredients to the surface, and shrinkage at the surface. A thicker material was harder to puff due to its increased mechanical resistance. Higher microwave power, leading to higher rate of evaporation, increased expansion. Evolution of mechanical properties of the crust greatly affected the final shape of the puffed product. In overall understanding, critical determinants of a puffing process were attributed to three material factors (reduced surface permeability, optimal moisture content, and deformability) and two process factors (intense heat and higher internal pressure from evaporation).     

微波膨化即食金枪鱼皮工艺条件的优化

为研究微波膨化即食金枪鱼皮的最佳工艺,本文通过初始水分含量、水分均衡时间、微波膨化时间测定了金枪鱼皮的膨化度,并采用响应面法(response surface method)确定鱼皮微波膨化工艺最优条件。在此基础上,利用正交实验对金枪鱼皮的增脆工艺参数(热水烫漂时间、冰水急冷时间和氯化钾溶液质量浓度)进行优化,同时采用扫描电镜观察金枪鱼皮产品的组织结构,确定即食金枪鱼皮的最佳增脆工艺。结果表明,即食金枪鱼皮的膨化工艺最优条件为初始水分含量21.8%、水分均衡时间9.1 h、微波功率700 W、微波时间4 min,在此条件下,膨化度为(1.24±0.03);增脆最佳工艺为热水烫漂时间为2 min、冰水急冷时间2 min、氯化钾溶液质量浓度5.0 g/L,在该条件下制备微波膨化金枪鱼皮的破裂力为(41.17±0.28) N,膨化度为(1.25±0.02),产品质地疏松,口感酥脆;通过理化分析和扫面电镜观察发现,增脆后产品鱼皮的膨化度和酥脆度显著提高,并呈现纤维组织明显膨大与细微破断处增多。由此可知,采用适宜的微波膨化和增脆工艺加工金枪鱼皮,可制得一款质地和口感俱佳的即食金枪鱼皮产品。     

冬枣变温压差膨化干燥工艺研究

以冬枣为原料,采用变温压差膨化干燥技术,探讨了预干燥时间、抽空时间、膨化温度、抽空温度、停滞时间和膨化压力对冬枣膨化产品硬度、脆度、色泽和水分含量的影响。结果表明:膨化温度、抽空温度和抽空时间是影响产品膨化质量的关键因素;冬枣预干燥6h后,膨化温度85℃,抽空温度60℃,抽空时间2h为较适合工艺参数;停滞时间和膨化压力差在一定范围内对膨化产品的质量影响不大,实验确定停滞时间15min,膨化压力差0.2MPa为较适合工艺参数。     

Hot Air Puffing Kinetics for Soy-fortified Wheat-based Ready-to-Eat (RTE) Snacks

The soy-fortified wheat-based flat cold extrudate, after requisite steaming, was puffed in hot air using the high-temperature short-time (HTST) whirling-bed puffing system. The hot-air puffing was conducted at five different hot air temperatures, 200 to 240 °C at constant fluidizing air velocity of 3.95 m s⁻¹ for 50 s of puffing time. The initial moisture of sample was 0.4617 kg kg⁻¹ dm. The already existing 15 different thin layer-drying models were applied to determine the hot air puffing kinetics, based on puffing temperatures. It was found that the Page model could represent hot air puffing kinetics of the steamed flat cold extrudate within 99.3% accuracy. The effective diffusivity was found to be between 1.15623 × 10⁻⁹ and 2.58631 × 10⁻⁹ m² s⁻¹ for steamed flat cold extrudate in the temperature range of 200 to 240 °C. The activation energy for diffusion was found to be 2,341.824 kJ kg⁻¹. The optimum puffing conditions with respect to expansion ratio (ER) and sensory color score were found at puffing temperature of 220 °C and puffing time of 30 s. The variation in ER for the product was found to follow a linear relationship with moisture content of steamed flat cold extrudate during puffing. The Dincer Number for steamed flat cold extrudate puffed in fluidizing air at temperature 220 °C and 3.95 m s⁻¹ velocity was determined to be 276,223.8. This Dincer Number was used to predict the puffing time required to achieve predetermined moisture content of product. The prediction was found to be effective within 10% deviation from the values of experimental puffing time except during the initiation of puffing.     

微波膨化果蔬小食品的研究

探讨了微波膨化技术在山药和胡萝卜脆片加工中的应用。以膨化率为指标,结合感官评价,实验了添加不同比例的淀粉原料对山药及胡萝卜脆片膨化效果的影响,并讨论了样品初始水分含量、样品的厚度以及微波功率和时间对膨化率的影响,且通过正交实验确定了最佳膨化工艺条件。     

膨化技术及其在膨化食品生产中的应用

膨化技术作为一种新型食品生产技术,正逐步在食品工业中特别是在休闲膨化小食品的生产中得到广泛的应用。目前膨化食品的生产技术主要有挤压膨化技术和高温膨化技术两种。本文主要介绍这两种膨化技术的膨化机理。生产工艺和流程以及它们在膨化休闲小食品生产中的应用;并对微波膨化、供培膨化、真空油炸等新型食品膨化技术及其发展作了若干展望。     

Physical,chemical and nutritional characteristics of puffed quinoa

Puffed quinoa can be used as ready-to-eat breakfast food or as an ingredient in snack formulations. In this study, puffed quinoa products with and without starch–chitosan coating were developed by gun, extrusion and microwave puffing at different process conditions (pressure, power, moisture content and energy consumption). Size, bulk density, colour, expansion index, water absorption and solubility, microstructure, mechanical and thermal properties, chemical composition and in vitro digestibility of organic matter and proteins of popped quinoa were assessed. Optimal process conditions for gun puffing were maximum 1.31 MPa after 780 s, 500 r.p.m. and 180 s for extrusion puffing and 1200 W for 60 s applying microwave puffing at 18–20% moisture contents. Gun and extrusion puffing yielded high-quality popped quinoa with a biological availability of organic matter between 84–88% and 79–90% for proteins. Extrusion and gun puffing are the most promising processes to prepare quinoa snacks.     

Development of ready‐to‐eat rice starch‐based puffed products by coupling freeze‐drying and microwave

The rice starch mixtures with varying amylose contents (AC) of 0.12–19.00% weight were prepared by mixing waxy and nonwaxy rice starches. The 5% rice bran oil shortening was added in the starch paste. After gelatinisation, thin slabs of starch pastes were aged at 4 °C for 24 h. The aged slabs were dried by freeze‐drying to obtain 25% moisture content. A microwave oven set to 600 J s^?1 for 90 s was then used for puffing. The crucial factors affecting the snack purchase were texture and nutrition. The relative crystallinity and retrogradation enthalpy (?H_r) of freeze‐dried pellets increased with increasing the AC. From using a differential scanning calorimeter (DSC), endotherms of pellets were shown only when AC > 0.12%. An amylose–lipid complex was shown in pellets with AC ≥ 9.00%. Relationships between the AC and all puffed product properties were linear. Increasing AC provided greater hardness, fracturability, bulk density, but lower expansion ratio. From the sensory evaluation, the panellists preferred the puffed products with 9.00% AC. Increasing the AC gave higher crispness, hardness, brittleness, air cell opacity and density, but resulted in less puffiness. Thus, the microwave drying has the potential to puff a healthy expanded snack but giving the desirable properties depends on AC.     

Microwave puffing: Determination of optimal conditions using a coupled multiphase porous media - Large deformation model

Increased interest in microwave puffing is due to its ability to obtain low-fat and ready-to-eat healthy products. Determination of optimal conditions for this complex process has been difficult and although several patents exist on the concept, we are yet to see any large scale commercial use. A fundamental physics based modeling approach integrated with relevant experimentation, developed in this work, is an ideal framework to understand and optimize microwave puffing. The results showed that puffing may not be successful unless carried out using an intensive heating source such as microwaves. Addition of infrared and hot air leads to better quality product whereas using forced air convection is not desirable. There is an optimum initial moisture content depending on the puffing conditions. The study provides critical guidelines to food product/process developers for successful development, control and automation of microwave puffing, thereby leading to value-added nutritious products.     

膨化黑毛豆仁保藏期间的品质稳定性

采用微波联合气流膨化技术制备黑毛豆仁脆粒产品,在不同温度和相对湿度条件下保藏6个月,考察其水分含量、水分活度、VC、叶绿素、花色苷、色泽、感官质量及微生物指标的变化情况。结果表明：高温、高湿都可导致产品水分含量和水分活度的增加,VC、叶绿素和花色苷含量降低,a*值增大。膨化黑毛豆仁在温度低于20℃、湿度低于70%的条件下保藏6个月,感官品质良好、符合食品卫生标准。     

Optimisation of puffing naked barley

The expansion of volume (the puffing index) of naked barley was investigated at various operating conditions of the puffing process. The purpose was to optimise the manufacture of expanded grains of the naked barley cultivars that have exceptional nutritional value for humans. The influence of the following parameters on the puffing index was investigated: the mass and the moisture content of the charge of the puffing barrel, pressure and temperature during the puffing process, the cultivar of barley, pre-processing of the grain (grinding and polishing), adding water into the barrel and the sensory quality of the product.

A regression equation was established for the calculation of the puffing index as a function of the operating parameters. The puffing index is influenced especially by the operating temperature and pressure. There was no influence found of mass of the charge, the cultivar of barley, the degree of grinding of barley, washing of the grains and adding water on the puffing index. The puffing index is not the sole indicator of the quality of the expanded product. It is necessary to take into account the sensory evaluation. A quality expanded naked barley was obtained at the operating temperature of 550 °C and pressure from 0.9 to 1.0 MPa with the moisture content of the charge around 16.5%.     

变温压差膨化干燥对芒果品质的影响

以凯特芒果为原料,采用变温压差膨化干燥技术,探讨了切条厚度、预干燥后水分含量、膨化温度、膨化压力差、抽空温度、抽空时间和停滞时间对芒果膨化产品的硬度、脆度、色泽、膨化度和含水率的影响.结果表明:芒果膨化的最佳厚度为6 mm;预干燥后水分含量、膨化温度和抽空时间是影响芒果膨化产品品质的关键因素;预干燥后,含水量在61.7...     

魔芋胶膨化食品制备工艺研究

以魔芋精粉为主要原料,以糯米粉、预糊化淀粉和超微粉碎玉米粉为辅料,对魔芋胶膨化脆片的制作工艺进行了研究。通过实验确定了产品的制作工艺、主要工艺条件及配方。结果表明：魔芋精粉和水的比例为1：15的魔芋胶,糯米粉添加量为魔芋胶量40％,超微玉米粉添加量2％,预糊化淀粉添加量20％,经蒸煮、定型、干燥后的坯料水分含量在20％,使用微波功率700W、时间15s加热处理下膨化,所得产品膨化效果好,感官质量佳,产品抗消化性淀粉含量为17．5g／100g。     

微波膨化番木瓜混合脆片工艺研究

以番木瓜为主要原料，马铃薯淀粉、糯米淀粉和玉米淀粉为配料，对番木瓜混合脆片的加工工艺进行研究。结果表明，添加15％马铃薯淀粉和15％糯米淀粉，预干后水份含量在10％，采用微波功率为800W，微波膨化时间为25s，膨化后脆片的感官品质最佳。     

不同干燥方式对香蕉产品品质的影响

为了对比普通热风干燥、真空冷冻干燥、传统油炸干燥、真空干燥、真空微波干燥、变温压差膨化干燥6 种不同的干燥方式对香蕉干燥产品营养成分、微观结构、感官品质、风味成分、生产周期的影响。采用理化分析技术检测营养成分含量;扫描电子显微镜观察微观结构;固相微萃取气相色谱-质谱联用技术分析检测风味成分;评分法进行感官评价、变异系数综合评价。结果表明：6 种不同干燥方式下香蕉产品营养成分变化显著,变温压差膨化干燥和真空冷冻干燥可较好保留产品各种营养成分;电子显微镜扫描显示变温压差膨化干燥产品细胞空隙最大,感官评分最高;固相微萃取气相色谱-质谱联用分析结果表明6 种不同干燥方式下香蕉产品生成了不同种类风味物质和特有风味成分,变温压差膨化干燥和真空冷冻干燥能较好地保留鲜香蕉中的酯类物质。干燥方式综合评价结果为：真空冷冻干燥＞变温压差膨化干燥＞传统油炸干燥＞真空干燥＞真空微波干燥＞普通热风干燥。但真空冷冻干燥投资大,生产周期长;变温压差膨化干燥微观细胞结构空隙最大,赋予产品疏松多孔结构。综合考量产品营养成分、感官评分、风味物质、微观结构、生产周期五类评价指标得出,变温压差膨化干燥加工技术适用于香蕉干制品的生产加工。     

Effect of process parameters and soy flour concentration on quality attributes and microstructural changes in ready-to-eat potato-soy snack using high-temperature short time air puffing

High-temperature short time (HTST) air puffing has been found to be very useful process for production of potato-soy ready-to-eat snack food as it ideally produced highly porous and light texture. The process parameters considered viz. puffing temperature (185-255 °C) and puffing time (20-60 s) with constant initial moisture content of 36.74% and air velocity of 3.99 m/s for potato-soy blend with varying soy flour content from 5% to 25% were investigated using response surface methodology with central composite rotatable design (CCRD). The optimum product in terms of maximum expansion ratio (3.69), minimum hardness (2754.3 g) and maximum overall acceptability (7.3) were obtained with 10.31% soy flour blend in potato flour at the process conditions of puffing temperature (230.06 °C) and puffing time (25.46 s). Microstructural changes were evaluated at different stages (with an interval of 5 s) of HTST puffing for product obtained with the optimum processing conditions. The maximum expanded porous structures with larger cracks and smaller pits were recorded in the SEM micrographs at 20 s of HTST air puffing.     

Study of the puffing process of amaranth seeds by dielectric spectroscopy

Amaranth (Amaranth spp) is considered a pseudocereal with valuable nutritional characteristics. Amaranth grain is commonly used in cereal industry as expanded product obtained from the puffing operation. In this work, the puffing process of amaranth seeds with different water content was studied. Moreover, the seeds and puffed kernels were analyzed by Differential Scanning Calorimetry (DSC), image analysis, dielectric spectroscopy and Cryo-SEM. The results of the study allowed identifying different levels of water retention in amaranth seeds. Moreover, the expansion process was modeled determining the critical points, obtaining the state variables and the final product conditions. It was also performed a structural study of the amaranth seed and the puffed product. The dielectric properties were also measured for determining the optimal time for the puffing operation.