Use of Artificial Neural Network to Predict Temperature, Moisture, and Fat in Slab-Shaped Foods with Edible Coatings During Deep-Fat Frying

ABSTRACT: An artificial neural network (ANN) was developed to predict heat and mass transfer during deep-fat frying of infinite slab-shaped foods coated with edible films. Frying time, slab half-thickness, film thickness, food initial temperature, oil temperature, moisture diffusivity of food and film, fat diffusivity through food and film, thermal diffusivity of food, heat transfer coefficient, initial moisture content of food, and initial fat content of food (mf_o) were inputs. Temperature at the center (T₁), average temperature (T_ave), fat content (mf_ave), and moisture content (m_ave) of food were outputs. Four ANNs with 50 nodes each in 2 hidden layers with learning rate = 0.7 and momentum = 0.7 provided most accurate outputs, that is maximum absolute errors for T₁ and T_ave were < 1.2 °C, < 0.004 db for m_ave, and < 0.003 db for mf_ave. The predictions of mf varied linearly with mf.     

Development and application of soy‐protein films to reduce fat intake in deep‐fried foods

A soy protein film coating was developed and evaluated to reduce fat transfer in deep‐fried foods during frying. Soy protein isolate solutions (10% SPI) with 0.05% gellan gum as plasticizer cooled after being held at 80 °C for 20 min provided suitable films. There was a significant fat reduction (55.12 (±6.03)%db) between fried uncoated and coated discs of doughnut mix. The same films were used on potato fries. Some panellists observed a slight difference between the coated and uncoated fries but many preferred the coated fries over the uncoated ones. Penetration test on potato fries showed no significant difference between the texture of coated (SPI with gellan gum) and the uncoated fried samples. A solution of 10% SPI with 0.05% gellan gum is recommended for coating foods to reduce fat intake during deep‐fat frying. © 2000 Society of Chemical Industry     

油炸食品中潜在的几类危害物及其消减技术

油炸是一种传统的食品加工方式,被广泛应用于家庭烹饪与食品工业.油炸过程复杂且剧烈,若控制不当则极易产生一些加工危害物,从而对消费者健康造成不利影响.本文主要介绍油炸食品中几类典型危害物,包括反式脂肪酸、丙烯酰胺、多环芳烃、杂环胺的生成途径、影响因素、潜在危害及减控措施,以期为消费者饮食结构的合理调整、油炸食品工业的转型...     

可食性膜降低油炸鱼块含油量的研究

通过研究3 种可食性膜对降低油炸鱼块含油量的影响,探讨不同可食性膜、可食性膜在挂糊时的添加次序、可食性膜的质量分数以及不同比例的混合可食性膜复配后对油炸鱼块含油量的影响及其抑油效果。研究表明：3 种可食性膜与对照组相比均有显著的抑油效果(P ＜ 0.05),其中羧甲基纤维素钠(CMC-Na)效果最好,海藻酸钠次之,阿拉伯胶最小,其质量分数2% 的抑油率分别达到21.33%、16.97% 和9.99%;3 种可食性膜均在挂糊中添加的抑油效果最好;复配后按照CMC-Na:海藻酸钠=1:2 的比例配制的挂糊液抑油效果最好,其1% 质量分数的抑油率达到34.54%。     

多糖类可食性膜的研究进展

可食性膜是目前食品包装领域研究的重要方向,其中,多糖类可食性膜因具有均匀、透明等特点而备受青 睐。目前,多糖类可食性膜的研究主要集中在改善其应用性能的同时,赋予其抗氧化性、抑菌性等更多的生物活 性,因此展现出良好的应用前景。本文在简要介绍多糖类可食性膜的主要组成、性能的基础上,对其成膜机理、生 物活性及应用发展进行了综述。     

Structure and Texture Properties of Fried Potato Products

Potatoes are the fourth most important vegetable crop in the world, and in 2003, it was a 2.7 billion dollar business in the US alone. Nearly one-third of the potato production is processed into par-fried frozen potatoes and fried chips (snacks). Frying imparts desirable taste and textural properties to these products, the latter described usually by the sensorial term crispness. Frying is reviewed as a structuring process, and methodologies to determine texture in fried potato products are discussed. It is demonstrated that the histological and microstructural heterogeneity of potato tubers have hampered clear interpretation of experimental data and a rigorous modeling of frying. Moisture uptake during post-frying is critical in the loss of crispness (limpness) of fries and in softening of potato chips. Methods to evaluate these changes and alternatives to prolong the shelf life are discussed.     

Structure and Texture Properties of Fried Potato Products

Potatoes are the fourth most important vegetable crop in the world, and in 2003, it was a 2.7 billion dollar business in the US alone. Nearly one-third of the potato production is processed into par-fried frozen potatoes and fried chips (snacks). Frying imparts desirable taste and textural properties to these products, the latter described usually by the sensorial term crispness. Frying is reviewed as a structuring process, and methodologies to determine texture in fried potato products are discussed. It is demonstrated that the histological and microstructural heterogeneity of potato tubers have hampered clear interpretation of experimental data and a rigorous modeling of frying. Moisture uptake during post-frying is critical in the loss of crispness (limpness) of fries and in softening of potato chips. Methods to evaluate these changes and alternatives to prolong the shelf life are discussed.     

Initial Interfacial Tension and Oil Uptake by Deep-fat Fried Foods

Fundamental theory of surface chemistry was utilized to develop an equation for calculating initial interfacial tension between a product and liquid. The relationship provides a practical approach to overcome the complexity of quantitatively determining interfacial tension of foods. The range of interfacial tension between a restructured potato product and the frying medium was 0.01 to 5.23–10^?3 N/m. This range was determined using various frying media or additives. A power relationship was found between the initial interfacial tension and uptake of oil or other frying media. A model of capillary rise in porous media was implemented to explain the linear relationship between uptake and contact angle.     

可食性膜的研究进展

本文从可食性膜的分类及其特点、应用以及发展趋势等几个方面对可食性膜近几年来国内外研究进展进行了综述。     

Relationships Between Edible Coatings and Garlic Skin

Porous garlic skin was coated with cross-linked sodium alginate. Penetration of the hydrocolloid and cross-linking agents into the skin were detected by Fourier-Transform Infra-red, X-ray analysis, Inductively Coupled Plasma Atomic Emission Spectrometry and chemical micro-analysis. The skin structure, its wax coating and pores were studied to elucidate the means by which coating agents penetrate the skin. Pathways of skin penetration by gum were hypothesized. Gum penetrates by three pathways: through skin discontinuities, from beneath where the roots are found and directly through the skin. The coating adhered to the outer garlic skin and conformed to its shape.     

Preventing Moisture Transfer in a Composite Food Using Edible Films: Experimental and Mathematical Study

ABSTRACT: Water barrier properties of various edible films: acetylated monoglycerides (AMG), dark chocolate (DC), and wheat gluten (WG) were evaluated through water sorption isotherm, diffusivity, and permeability measurements. Diffusivity and sorption isotherm were then used in a mathematical model for predicting moisture transfer evolution in composite foods. It was successfully validated in agar gel/sponge-cake systems with the studied films at the interface. Using model predictions and relevant permeability measurement comparisons, AMG appeared to be the most efficient water vapor barrier films. Acetylation of monoglycerides seemed to be favorable to improve their water vapor transfer resistance mainly by reducing water solubility and despite a slight increase of water vapor diffusivity.     

植物提取物对油炸和焙烤类食品中丙烯酰胺抑制效果的研究进展

丙烯酰胺是一种在高温下加工的食品中美拉德反应的副产物,常见于油炸和焙烤类食品中,已被认为是潜在的致癌物。越来越多的研究表明,可以通过添加从植物中提取的天然活性成分来抑制食品加工过程中丙烯酰胺的形成,由于天然植物天然环保、取材易、成本低,因此是一种符合工业需求的添加剂。本文着重对香辛料提取物、水果提取物、叶茎类提取物和谷豆类提取物抑制丙烯酰胺的效果研究进行了综述,结合抑制效果和对产品的感官影响,得出较为可行的抑制剂为茴香提取物、竹叶提取物、葡萄副产品和黑花生衣提取物。针对目前的研究现状对未来的潜在方向提出了展望,以期为食品工业中抑制丙烯酰胺提供更多的方法。     

油炸与油炸食品中的反式脂肪酸产生、危害及消减

反式脂肪酸(trans fatty acids,TFA)一般天然存在于反刍动物体内,或在油脂精炼、加热、氢化加工过程中产生。不恰当的加工方式,如高温加热或油炸等,也会产生一定量的TFA,且不同加工条件对TFA生成量的影响程度不同。TFA对人体健康的影响是多方面的,因此更需要在油脂烹调过程中对其加以控制。本文从TFA的结构、来源、不同加工条件对其形成的影响、危害和消减措施等方面做出阐述,对我国目前暴露量进行分析并提出相关的建议。     

琼脂-麦芽糊精共混物的成膜特性研究

将琼脂与不同水解程度的麦芽糊精按一定比例分别混合,考察共混液的黏度以及所成膜的透明度、机械性能和透湿性。结果表明:琼脂-麦芽糊精共混液的黏度主要取决于琼脂的质量分数,琼脂质量分数小于3%,有利于流延成膜。低DE值的麦芽糊精与琼脂共混膜的机械性能、阻湿性优于高DE值的麦芽糊精与琼脂形成的共混膜,但高DE值的麦芽糊精-琼脂共混膜的透明度较高,并且膜面较为光滑平整。     

煎炸食品的品质和风险因子研究最新进展

如何让煎炸食品更美味、更健康是食品科学不断追求的目标.主要对影响煎炸食品风味、口感(质构)、吸油等品质和新风险因子等方面2019—2022的最新研究进展进行综述;系统阐述其"宽钟罩"型的风味曲线的来源、演变及物质关系;介绍口感(质构)的物理表征和影响机制,以及煎炸食品的吸油机理和降低含油率的新技术;并进一步对煎炸过程的...     

改性淀粉基可食性膜的制备及性能研究

以改性淀粉为成膜基材,采用溶液流延法制备可食性膜.研究了改性淀粉种类及浓度、增塑剂种类、甘油添加量、增强剂种类、普鲁兰多糖添加量对膜性能的影响.结果表明,采用羟丙基交联淀粉为基材,淀粉浓度为5 g/100 mL,增塑剂甘油添加的质量分数为30％,增强剂普鲁兰多糖添加的质量分数为淀粉质量的10％,制备的淀粉膜综合性能较好...     

Physical, Morphological, and Barrier Properties of Edible Casein Films with Wax Applications

ABSTRACT:  The overall research objective was to investigate the effects of wax application to casein films on the physical, morphological, mechanical, and water barrier properties of the films. Casein films were prepared by cross-linking with zein hydrolysate using transglutaminase. Wax was either incorporated into the film-forming solution or coated onto the casein films. The physical, morphological, and mechanical properties of wax-incorporated or wax-coated casein films were characterized. The wax-casein films exhibited darker color than casein film, and the film thickness ranged from 0.2 to 0.4 mm. Wax application significantly decreased the tensile strengths and Young's Modulus of casein films. The wax-incorporated films exhibited a greater reduction in tensile strength and Young's Modulus than the wax-coated films. The microstructures of wax-casein films were relatively smooth and uniform when observed under a scanning electron microscope. Wax applications significantly decreased the water vapor permeability (WVP) of the casein films, and the wax-coated casein films exhibited a greater decrease in WVP than the wax-incorporated films.     

食用油中脂肪伴随物的营养与功能

我国油脂营养和食用油消费领域存在片面强调脂肪酸平衡而忽视脂肪伴随物营养与功能的误区.本文从法国悖论、地中海式饮食、爱斯基摩人膳食的角度出发,阐述了脂肪伴随物与人体健康的密切关系.并且采用饱和脂肪与心血管病之间关系、脂肪摄入与乳腺癌的相关性、高脂膳食氧化应激与抗氧化剂的干预作用等营养学的最新研究结果,表明饱和脂肪酸与心血管疾病之间不存在显著的相关性,摄入富含有益脂肪伴随物、营养全面的食用油是油脂营养的关键所在.     

氯化钙改性谷朊粉可食性复合膜的研究

本文研究了交联剂氯化钙对小麦谷朊粉复合膜性能的影响，应用综合评分法得出，氯化钙的最佳添加浓度为0．67％，此时综合得分为最高达120．99，在此条件下制得的复合膜，其拉伸强度提高了13．4％，水蒸气透过系数（WVP）降低了7．3％。应用氯化钙交联可以明显提高可食陛膜的强度，改善复合膜的机械幽抱。