Frozen Blueberry-soy Dessert Quality

ABSTRACT: Lowbush or wild blueberries ( Vaccinium angustifolium Ait.) and soy protein offer many complementary health benefits; thus, combinations of these 2 foods may appeal to health-conscious consumers. Four frozen dessert formulations were prepared with soy protein isolate and different amounts of blueberry concentrate and puree. Fat content (3% or 10%) was adjusted with soybean oil and nondairy creamer. Consumers ( n = 40) from the campus community used a 9-point hedonic scale to assess acceptability. The 10% fat content and 8.6% blueberry concentrate formulation received the highest overall acceptability (6.63, P < 0.05), compared with formulations with 10% fat and 17.2% blueberry concentrate and 3% fat and 12.9% blueberry concentrate. More than 1 /3 of the panelists are trying to increase blueberry consumption, 20% want to increase soy, and 20% want to eat more of both foods. Development of palatable desserts combining lowbush blueberries and soy protein could lead to increased consumption of both healthy ingredients.     

Storage effects on anthocyanins, phenolics and antioxidant activity of thermally processed conventional and organic blueberries

BACKGROUND: Consumer demand for products rich in phytochemicals is increasing as a result of greater awareness of their potential health benefits. However, processed products are stored for long‐term and the phytochemicals are susceptible to degradation during storage. The objective of this study was to assess the storage effects on phytochemicals in thermally processed blueberries. Thermally processed canned berries and juice/puree were analysed for phytochemicals during their long‐term storage. RESULTS: The phytochemical retention of thermally processed blueberries during storage was not influenced by production system (conventional versus organic). During 13 months of storage, total anthocyanins, total phenolics and total antioxidant activity in canned blueberry solids decreased by up to 86, 69 and 52% respectively. In canned blueberry syrup, total anthocyanins and total antioxidant activity decreased by up to 68 and 15% respectively, while total phenolic content increased by up to 117%. Similar trends in phytochemical content were observed in juice/puree stored for 4 months. The extent of changes in phytochemicals of thermally processed blueberries during storage was significantly influenced by blanching. CONCLUSION: Long‐term storage of thermally processed blueberries had varying degrees of influence on degradation of total anthocyanins, total phenolics and total antioxidant activity. Blanching before thermal processing helped to preserve the phytochemicals during storage of blueberries. Copyright © 2011 Society of Chemical Industry     

Effects of Food Processing on Blueberry Antiproliferation and Antioxidant Activity

Cultivated highbush (Vaccinium corymbosum L.) and wild lowbush (Vaccinium angustifolium Ait.) blueberries are excellent sources of phytochemicals that are believed to have significant biological activity. The objective of this study was to determine whether incorporation of blueberries into food products affects their phenolic content or antioxidant and antiproliferation activity. Several blueberry fruit‐containing products including fresh, individually quick frozen (IQF), freeze‐dried, spray‐dried, heat‐dried, cooked, juice concentrate, pie filling, and jam were fractionated to remove sugars and isolate groups of phytochemicals based on solubility. The fractions were analyzed for total phenolics and assayed for ferric reducing antioxidant power (FRAP) antioxidant activity, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity, and hepa‐1c1c7 antiproliferative activities. For both cultivated and wild berries, fresh and IQF berries had the highest total phenols, antioxidant activity, and antiproliferation activity. Whole freeze‐dried wild blueberries also retained significant antiproliferative activity in 2 fractions eluted with acetone (fraction 4, 4% of control cell growth at 20 (μg/mL) and 50% aqueous acetone (fraction 5, 69% of control cell growth at 20 (μg/mL) and ranked close to the activities recorded for fresh (30% of control cell growth at 20 (μg/mL for fraction 5) and IQF whole fruit (27% of control cell growth at 20 (μg/mL for fraction 5). Products that were heat‐processed retained most of the antioxidant activity and total phenolics found in unprocessed whole fruit. However, the heat‐treated products lacked or had diminished antiproliferation activity, suggesting that although products may be high in phenolic compounds and antioxidant activity, some forms of bioactivity may be compromised by harsh processing methods.     

How Do Consumer Attitudes Influence Acceptance of a Novel Wild Blueberry–Soy Product?

ABSTRACT:  Acceptance of healthful foods by consumers is not yet well understood. In this study, 3 formulations of frozen dessert bars were prepared containing both soy and wild blueberries. Soy content was controlled to provide an amount of soy protein that qualified for the health claim for soy and reduced risks for cardiovascular disease. Consumers were asked to complete the Health and Taste Attitude Scales (HTAS) and then evaluate the acceptability of the 3 frozen bar types using a 9-point hedonic scale. One week after the 1st session, the participants returned. Approximately half were given information to read regarding the health benefits of soy protein, the other participants were given no information. The samples were then presented a 2nd time and labeled with their soy protein content. Changes in hedonic scores between sessions were compared and correlated with HTAS ratings. Nutrition information generally did not affect acceptability scores.     

响应面法优化胡萝卜-发酵蓝莓奶片的工艺研究

以脱脂奶粉、胡萝卜粉、发酵蓝莓冻干粉为原料制备胡萝卜-发酵蓝莓奶片,并进行相关工艺优化。通过正交试验确定发酵蓝莓的最佳条件,用总抗氧化能力进行鉴定,采取真空冷冻干燥的方法将蓝莓发酵液制成冻干粉。以奶片感官评分为响应值,通过单因素实验和响应面法优化奶片工艺。结果表明,发酵蓝莓的最佳条件为发酵温度35 ℃、菌种添加量5%、发酵时间25 h,此条件下蓝莓发酵液的总抗氧化能力为230.158 U/mL,较蓝莓汁发酵前提高了33.18%。奶片的最佳制备工艺配方为奶粉:果蔬粉=2:1、麦芽糖醇添加量7.5%、柠檬酸添加量0.3%、硬脂酸镁添加量0.5%,此条件下的感官评分为95分。本产品保有蓝莓的营养价值,具有较好的市场应用前景。     

Recent progress of soybean protein foods: Chemistry,technology, and nutrition

Abstract

The most important chemical reactions during the process of soybean protein foods are the intermolecular reactions among the residues exposed on the surface of the protein molecules through the denaturation process. In native soybean protein molecules, most amino acid residues responsible for the reactions—such as cysteine (‐SH), cystine (S‐S), and hydrophobic amino acid residues—are buried in the inside region of the molecule, inaccessible to water. These residues become reactable with each other through the exposure from the inside by heat denaturation during processing. The unique textures of soybean protein foods, such as tofu, kori‐tofu, yuba, and texturized products produced by extruder, etc., are the results of both the intermolecular interchange reaction between the exposed ‐SH and S‐S groups and the intermolecular hydrophobic reaction among the exposed hydrophobic amino acid residues. The exposure of amino acid residues is also important for the hydrolysis of soybean proteins by enzymes, through which soy sauce is produced, because the cleavage of the peptide bonds is carried out after binding between the active sites of the enzymes and the enzyme‐specific amino acid residues exposed through denaturation. These facts indicate the importance of the three‐dimensional structures of soybean protein molecules in the technology of soybean protein foods. Recently great progress has been made in the manufacturing techniques of soybean protein foods, such as soy milk, tofu, abura‐age, textured protein products, and soy sauce. The quality of soy milk and tofu was very much improved by controlling the action of the biologically active substances such as lipoxygenases and β‐glucosidases which are contained in soybeans and responsible for the production of off‐flavor. A new abura‐age, whose texture does not deteriorate during frozen storage or drying, was developed by using soybean protein isolate and oil as materials. A new type of textured protein product was also developed: a deep‐fat‐fried nugget with unique texture and flavor. This product is textured through a twin‐type extruder. For soy sauce manufacturing new biotechnology has been applied on the pilot‐plant scale. This is a system of continuous fermentation through bioreactors with the immobilized whole cells of microorganisms, by which the fermentation term is shortened strikingly. New and important discoveries were made on the nutrition of soybean proteins. According to recent experiments using human beings, the amino acid score of soybean proteins is 100 for persons more than 2 years old, indicating that the nutritive value of soybean proteins is equal to animal proteins. Further, it was elucidated that soybean proteins have cholesterol‐lowering action. A discussion is presented on the future of the soybean protein foods.     

FORMULATION OF BEVERAGES CONTAINING BYPRODUCTS OF OSMOTIC DEHYDRATION OF LOWBUSH BLUEBERRIES

The manufacture of osmotically dehydrated lowbush blueberries, Vaccinium angustifolium, produces a liquid byproduct, blueberry extract (BE), containing sugar and blueberry juice. The unique blueberry color and flavor in BE were utilized in a simple beverage containing spring water, 30% or 50% BE (w/v), and 0.1% or 0.2% citric acid. The beverages with 50% BE had significantly higher (p ≤ 0.001) brix and were significantly (p ≤ 0.001) darker, less red, and more blue. Fifty consumers rated the beverages containing 50% BE as significantly more acceptable in color (p ≤ 0.001) and fruit flavor (p ≤ 0.05), but least acceptable (p ≤ 0.001) for sweetness. Samples with 0.2% citric acid were significantly higher (p ≤ 0.001) in overall acceptability. BE can be used to provide flavor and color in fruit beverages while reducing a waste disposal problem for blueberry processors.     

Effect of thermal treatments on phytochemicals in conventionally and organically grown berries

BACKGROUND: Consumer demand for organic foods is increasing despite a lack of conclusive evidence of nutritional superiority of organically grown produce. The objective of this investigation was to evaluate the effects of thermal treatments on phytochemicals in conventionally and organically grown berries. Two cultivars of conventionally and organically grown red raspberries and blueberries were analysed for total anthocyanins, total and specific phenolic compounds and total antioxidant activity. Fresh berries were thermally processed into cans and juice/puree with and without blanching, and the changes in phytochemicals were monitored. RESULTS: Total anthocyanin and phenolic contents of berries were not influenced by the agricultural production system. Total antioxidant activity of berries was also not influenced by the production system, but antioxidant activity varied significantly between cultivars. After canning, total anthocyanins decreased by up to 44%, while phenolic contents and antioxidant activity of both berries generally increased by up to 50 and 53% respectively. The level of changes in phytochemicals during berry puree/juice processing was influenced by blanching and type of berries. CONCLUSION: Phenolic contents and antioxidant activities of berries increased while total anthocyanins decreased during canning. Blanching prior to puree/juice processing improved the retention of phytochemicals in blueberries. Copyright © 2010 Society of Chemical Industry     

CONSUMER PREFERENCE AND MECHANICAL PROPERTY ASSESSMENT OF MAINE WILD BLUEBERRIES FOR THE FRESH PACK MARKET1

Maine wild fresh blueberries were purchased from a cooperative twice (tests 1 and 2) during the 1997 field season and used to determine the relationship of consumer preference and textural properties. Berry diameter was used to establish 3 size classes and a consumer panel evaluated teaspoon-sized samples and indicated their opinion of flavor, texture and overall quality attributes using a 9-point hedonic scale. Ranked preference for size was conducted in a separate area following the acceptability evaluation. At the same time the consumer samples were drawn, three berries were subsampled and subjected to a compression test. Two replications of the test were made to evaluate texture/sensory interactions of Maine wild blueberries throughout the harvest period; test 1, one week into the four-week harvest. Based on size class, there were no significant differences in acceptability attributes; however, differences were detected in the mechanical tests. Slight differences in consumer preference were detected in test 2, which took place three weeks into the harvest cycle, and significant differences were also found in the mechanical tests. Differences between test 1 and 2 can be attributed to blueberry maturity. These results compare with previously published data on Maine wild blueberries.     

Effect of soy flour addition and heat-processing method on nutritional quality and consumer acceptability of cassava complementary porridges

BACKGROUND: The nutritional quality of cassava complementary porridge was improved through extrusion cooking and compositing with either defatted or full fat soy flour (65:35 w/w), and product acceptability by mothers with children of the target population was evaluated. RESULTS: The protein digestibility‐corrected amino acid score (PDCAAS) of extrusion‐ and conventionally cooked composite porridges was within the recommendations for complementary foods. The kinetics of starch digestibility showed that all porridges had a rapid rate of starch digestibility, but the rate was lower when defatted soy flour was added and lowest when full fat soy flour was added. The formation of amylase‐lipid complexes as shown by X‐ray diffraction and differential scanning calorimetry can be attributed to the lower digestibility of extrusion‐cooked porridge with full fat soy flour. If fed thrice per day, extrusion‐cooked porridge with defatted or full fat soy flour would meet the energy, protein and available lysine requirements of a child aged 6–8 months receiving low or average nutrients from breast milk. All porridges were well received by Mozambican mothers who use cassava as a staple food. The mean scores for sensory liking of all porridges were 3 and above on a five‐point hedonic scale. CONCLUSION: Extrusion‐cooked cassava/soy flour porridges have good potential for use as high‐energy/high‐protein complementary foods and have acceptable sensory properties. Copyright © 2012 Society of Chemical Industry     

苦瓜营养豆腐的研制

以苦瓜和大豆为原料研制了苦瓜营养豆腐,其最佳工艺参数:豆浆料水质量比为1∶6,葡萄糖酸内酯添加量0.25%,豆浆苦瓜汁体积比为6∶2。该产品呈淡绿色,具有一定的苦瓜香和纯正的豆香味,并有保健和美容作用,发展前景广阔。     

不同品种蓝莓和菌种酿制蓝莓酒的香气成分分析

分别以速冻野生和种植蓝莓为原料,以酵母菌株QD-1、QD-2酿造蓝莓酒。采用气相色谱-质谱联用(GC-MS)技术对蓝莓果汁及蓝莓酒的香气成分进行分析和比较。实验结果表明,野生蓝莓和种植蓝莓果汁中分别检测出12种、7种香气成分;由菌株QD-1酿造野生蓝莓酒和种植蓝莓酒中分别检测出39种、40种香气成分;由菌株QD-2酿成野生蓝莓酒和种植蓝莓酒中分别检测出39种、27种香气成分。通过对比分析得知,不同品种蓝莓和菌种对酿制的蓝莓酒香气成分都有很大的影响。     

常见大豆制品中蛋白质的体外消化特性

本研究以常见大豆制品（大豆分离蛋白（soy protein isolate,SPI）、微波大豆、水煮大豆、豆浆、氯化钙豆腐和氯化镁豆腐）为研究对象,采用标准的静态体外消化模型——INFOGEST 2.0,测定不同时间点胃肠消化产物的完整蛋白、分子质量分布、游离氨基浓度和粒径大小,以探究大豆蛋白的消化特性。结果表明,不同加工方式均能促进大豆蛋白的消化。经过胃消化阶段后,几种大豆制品中部分蛋白被消化。而肠消化后,大豆蛋白均被彻底消化为短肽。相较于SPI,大豆经微波和水煮处理后,大豆蛋白的游离氨基浓度明显增加,但微波加热后大豆蛋白消化得更彻底;豆浆中大豆蛋白的消化程度低于氯化钙豆腐和氯化镁豆腐,两种豆腐中大豆蛋白的消化程度没有明显差异。总之,不同加工方式处理大豆均能不同程度地促进大豆蛋白的消化。本研究有助于更好地了解不同加工方式得到的大豆制品中大豆蛋白的消化特性,为人们摄取植物蛋白提供参考。     

9种大豆制品中转基因成分定性PCR检测

本研究从豆粕、豆粉、豆腐等9种大豆产品中提取到高质量的DNA,在对内标准基因Lectin进行扩增的基础上,设计相应的特异性引物,建立了稳定的定性PCR反应体系,对35S启动子基因、外源目的基因Cp4-epsps基因进行了扩增,发现豆粕、豆奶粉、豆腐、豆皮、豆豉中含有转基因成分,而其它产品中未发现转基因成分存在.     

Antioxidant activity,anthocyanins, and phenolics of rabbiteye blueberry (Vaccinium ashei) fluid products as affected by fermentation

Frozen rabbiteye blueberries (Vaccinium ashei) were processed into juice (BJ), wines made without (BW1) or with (BW2) skin contact fermentation, and vinegars made from BW1 (JV), BW2 (WV) or blueberries (BV). Total phenolics, total anthocyanins, antioxidant activities (beta-carotene bleaching assay and ferric thiocyanate assay), and antiradical activity (DPPH radical-scavenging method) of these fluid products were determined. The differences in total anthocyanin contents of all blueberry products were significant. The BW2 had the highest content of anthocyanins and polyphenols and the highest beta-carotene bleaching activity and antiradical activity. Acetification decreased total anthocyanin content, total polyphenols and antioxidant activities. Correlations indicate that anthocyanins made significant contributions than did phenolics to antioxidant activities of products. The abilities of BJ, BW1 (wine from blueberry juice), and BW2 to inhibit linoleic acid peroxidation were high (∼95%). The abilities of vinegar products to inhibit linoleic acid peroxidation were low. The results indicate that skin-contact fermentation is a better method for obtaining higher antioxidant activity of blueberry products. Also, acetification significantly decreased anthocyanins and antioxidant activities.     

Processed Tart Cherry Products—Comparative Phytochemical Content,in vitro Antioxidant Capacity and in vitro Anti‐inflammatory Activity

Abstract: Processing of fruits and vegetables affects their phytochemical and nutrient content. Tart cherries are commercially promoted to possess antioxidant and anti‐inflammatory activity. However, processing affects their phytochemical content and may affect their related health benefits. The current study compares the in vitro antioxidant capacity and anti‐inflammatory cyclooxygenase activity of processed tart cherry (Prunus cerasus) products—cherry juice concentrate, individually quick‐frozen cherries, canned cherries, and dried cherries. Cherry products were analyzed for total anthocyanin and proanthocyanidin content and profile. On a per serving basis, total anthocyanins were highest in frozen cherries and total proanthocyanidins were highest in juice concentrate. Total phenolics were highest in juice concentrate. Juice concentrate had the highest oxygen radical absorbance capacity (ORAC) and peroxynitrite radical averting capacity (NORAC). Dried cherries had the highest hydroxyl radical averting capacity (HORAC) and superoxide radical averting capacity (SORAC). Processed tart cherry products compared very favorably to the U.S. Dept. of Agriculture‐reported ORAC of other fresh and processed fruits. Inhibition of in vitro inflammatory COX‐1 activity was greatest in juice concentrate. In summary, all processed tart cherry products possessed antioxidant and anti‐inflammatory activity, but processing differentially affected phytochemical content and in vitro bioactivity. On a per serving basis, juice concentrate was superior to other tart cherry products. Practical Application: Processing of fruits and vegetables affects their chemical and nutrient content and perhaps their related health benefits. Comparative studies are valuable to ascertain the effects of processing on fruit and vegetable chemical content and bioactivity. Here we present tart cherries as a model for this type of detailed comparison.     

Consumer Acceptability of Low Fat Foods Containing Inulin and Oligofructose

Inulin and oligofructose were used as fat replacers in Anzac cookies, blueberry muffins, carrot cake, chocolate cake, lemon cheesecake, ice cream, and beef sausages at levels ranging from 4 to 13g/100g, achieving a significant reduction in fat content (20% to 80% relative). These foods were rated as acceptable by an untrained taste panel, but scored consistently lower than their full‐fat counterparts (controls). Regression analysis showed that, unlike the controls, texture was more important than flavor in determining overall acceptability of the low‐fat foods. Inulin and oligofructose are readily incorporated into bakery and meat formulations, but their use might be limited by adverse physiological effects when consumed at high levels.     

二次浆渣共熟制浆工艺优化研究

该试验通过对二次浆渣共熟制浆工艺进行优化,以期提高大豆蛋白质的提取率及豆浆中多糖的含量,使豆腐的品质得到提高。结果表明,优化后的最佳工艺条件为一浆和二浆配比6∶2（V∶V）,一渣和水配比1∶2（g∶mL）,混合豆浆加热温度95 ℃,混合豆浆加热时间3 min。在此条件下,制得的豆腐感官评分为（79.33±0.47）分,蛋白质含量为（7.43±0.05） g/100 g,其他指标均良好。     

Effect of Formulation on Physicochemical Properties and Water Status of Nutritionally Enriched Fresh Pasta

A standard fresh pasta formulation (STD, the control sample) was modified by introducing soy and carrot ingredients both in dry and in liquid forms (soy and carrot flour and soy milk and carrot juice) to obtain eight nutritionally enriched fresh pasta samples with different formulations. The effect of formulation on selected physicochemical properties and water status of fresh pasta were studied. Colour, texture (force at rupture and extensibility), and cooking loss were found significantly affected by the formulation. Soy and carrot decreased the force at rupture and extensibility of fresh pasta and increased the solids loss during cooking. Improper gluten network development due to either a steric hindrance of soy and carrot solids or improper water availability for gluten hydration due to different water–solid interaction developed were hypothesized. Soy and carrot ingredients significantly altered the water dynamics in the pasta matrix at different space-time levels (macroscopic, moisture content and water activity; macromolecular, frozen water content; molecular, proton nuclear magnetic resonance relaxometry) of fresh pasta in a manner dependent upon the physical state of the added ingredient. Soy flour increased both the frozen water content and the overall proton mobility (¹H FID, ¹H T ₁ and T ₂) of fresh pasta while these parameters did not markedly differed from STD when soy milk was used. The presence of both carrot flour and carrot juice decreased significantly the frozen water content of fresh pasta but, at a molecular level, carrot flour altered the proton molecular mobility, while carrot juice did not.