山药罐头加工中护色条件的研究

目的 研究山药罐头加工中最佳的护色条件。方法用柠檬酸、维生素C及氯化钙为护色剂进行护色实验。结果最佳护色条件为：0．5％柠檬酸＋1．0％维生素C＋0．25％氯化钙。结论3种护色剂配合处理后可防止山药褐变，提高山药罐头质量。     

马铃薯丝加工中的褐变因素及其控制

研究了马铃薯中多酚氧化酶的最适温度，最佳ｐＨ值及热稳定性等多方面的特性。筛选了以亚硫酸氢钠，抗坏血酸，柠檬酸，氯化钙为主剂的护色剂，提出了马铃薯丝在加工与贮存过程中抑制其褐变的工艺流程与技术要点。     

柠檬酸亚锡二钠对双孢菇罐头的护色作用

研究柠檬酸亚锡二钠(DSC)对双孢菇罐头的护色作用。在双孢菇切片预处理和罐头汤汁中添加DSC与其他常用护色剂及其正交复合护色剂,测定产品的PPO残余酶活和褐变度BD等质量指标。在预处理阶段,较之植酸、柠檬酸、VC,DSC对双孢菇酶促褐变有更佳的抑制作用,预煮前以最佳复合护色剂(质量分数)0.2%柠檬酸,0.03%DSC,0.02%植酸,0.03%VC护色液浸泡预处理可有效防止菇片褐变;DSC用于双孢菇罐头汤汁比其他护色剂有更显著的褐变抑制效果,汤汁复合护色剂的最佳参数组合为(质量分数):0.03%DSC,0.02%植酸,0.3%CaCl2和0.1%柠檬酸,各因素对其影响程度为:DSC>植酸>氯化钙。DSC复合护色剂可有效抑制双孢菇罐头褐变,效果可与焦亚硫酸钠媲美,可作为蘑菇罐头中替代焦亚硫酸钠的新型安全高效护色剂。     

双孢菇干制的非硫护色剂研究

为解决双孢菇干制过程中的褐变问题,选用柠檬酸、氯化钙、氯化钠、抗坏血酸、乙二胺四乙酸二钠、L-半胱氨酸和六偏磷酸钠7种护色剂对双孢菇进行护色处理。单因素实验表明:不同护色剂对双孢菇褐变都有一定的抑制作用,其中氯化钙、抗坏血酸、L-半胱氨酸和六偏磷酸钠护色效果明显。通过响应面优化实验得出非硫复合护色剂的最佳组合为:抗坏血酸0.053%,L-半胱氨酸0.021%,六偏磷酸钠0.047%,氯化钙0.061%。该复合护色剂重复使用25次仍有很好的护色效果。     

川明参无硫护色工艺

为解决川明参加工处理后产生的褐变问题,采用新鲜川明参为原料,以L*、b*值及褐变度为评价指标,通过单因素试验研究柠檬酸、氯化钙、氯化钠、L-半胱氨酸、抗坏血酸5种不同浓度的护色剂对川明参的护色效果,通过正交试验筛选适宜川明参加工的护色剂种类及添加量。结果表明,单一护色剂中柠檬酸、氯化钙、氯化钠护色效果较好;川明参在最佳复合护色剂柠檬酸浓度0.5%,氯化钙浓度0.2%,氯化钠浓度1.6%中浸泡60 min,所得L*值为62.03, b*值为18.20,褐变度为0.135。     

茶多酚在抑制板栗褐变中的应用

本研究比较了茶多酚同抗坏血酸和NaHSO3抑制板栗预煮褐变的效果．结果表明：茶多酚与柠檬酸和EDTA共用时，可以非常有效地抑制板栗预煮褐变，其效果明显优于抗坏血酸或NhHSO3与柠檬酸和EDTA共用的效果，并确定了预煮液的最佳配方为0.01％茶多酚 0.2％柠檬酸 0．2％EDTA．     

山药罐头加工中护色条件的研究

目的研究山药罐头加工中最佳的护色条件。方法用柠檬酸、维生素C及氯化钙为护色剂进行护色实验。结果最佳护色条件为:0.5%柠檬酸 1.0%维生素C 0.25%氯化钙。结论3种护色剂配合处理后可防止山药褐变,提高山药罐头质量。     

响应曲面法优化花生芽菜护色剂配方

以花生芽菜为原料,选取三种护色剂氯化钠、柠檬酸及抗坏血酸进行护色试验。单因素试验结果表明三种护色剂均对花生芽菜具有良好的护色效果。在单因素试验基础上,采用响应曲面法,以褐变抑制率为评价指标,分析不同护色剂配方对花生芽菜褐变抑制率的影响。结果表明:三种护色剂对花生芽菜褐变抑制率的影响顺序为抗坏血酸>氯化钠>柠檬酸,最佳配方为氯化钠0.31g/100mL、柠檬酸0.93g/100mL、抗坏血酸0.57g/100mL,在此条件下褐变抑制率为73.13%。     

鲜切莲藕片的防褐变研究

按照采用均匀设计的要求，分别设计出以不同浓度的柠檬酸、抗坏血酸，氯化钙和焦磷酸钠的7种组合来处理鲜切莲藕。研究了莲藕在贮藏期间的褐变度、可溶性固形物、多酚氧化酶、总酚含量等指标的变化，确定出了0．2％柠檬酸＋0．7％Vc＋0．3％-0．4％氯化钙＋0．2％焦磷酸钠的组合，可以有效抑制鲜切莲藕的褐变，在5℃下货架期达16d。为鲜切莲藕的后续加工提供了依据。     

鲜切雪莲果护色保鲜工艺的研究

以雪莲果为试材,研究鲜切雪莲果防酶促褐变的工艺.实验中将物理方法和化学方法结合起来,采用正交实验筛选出鲜切雪莲果的最佳组合护色剂,从而确定雪莲果最优组合防褐变的工艺.结果表明:抗坏血酸、柠檬酸、EDTA-Na2和NaC1都有抑制褐变的效果,但组合抑制剂的护色效果比单元抑制剂好.且最佳组合护色剂为:0.15%抗坏血酸+O.10%柠檬酸+0.05%EDTA-Na2+1.5%NaC1.     

响应面法优化兰州百合干无硫护色剂配方

为有效解决兰州百合干制过程的褐变问题,开发兰州百合干无硫护色技术,选取护色剂抗坏血酸、柠檬酸、L-半胱氨酸、氯化钠为影响因子,以百合干色泽（L*值）为响应值。在单因素试验的基础上,采用Box-Behnken试验设计构建二次多项式回归方程的模型,进行响应面分析。结果表明：护色剂复合作用对百合干色泽的影响程度依次为：L-半胱氨酸＞抗坏血酸＞氯化钠＞柠檬酸,复合护色剂的最优配方（质量分数）为：0.65%氯化钠、0.3%抗坏血酸、0.3% L-半胱氨酸、0.8%柠檬酸,在此条件下,加工的百合干色泽L*值为78.69,护色效果好。     

褐变抑制剂对干制香蕉片护色效果的影响

为了提高香蕉片干制后的颜色品质,获得最佳护色方法,以褐变度和L*值为考察指标,研究植酸、抗坏血酸、氯化钠、EDTA、柠檬酸5种褐变抑制剂对干制香蕉片颜色品质影响,并优选出提高干制香蕉片颜色品质的护色方法。结果表明:单一护色剂护色效果依次为植酸柠檬酸EDTA氯化钠抗坏血酸,将鲜切香蕉片放入植酸(质量分数为0.9%)和柠檬酸(质量分数为0.3%)组成的复合护色液中浸泡20 min,干制后的香蕉片L*值达65.93,褐变抑制率达84.4%。     

低糖无硫南瓜脯加工工艺研究

以果葡糖浆代替部分蔗糖,通过对南瓜护色、浸胶、真空渗糖等方面研究,确定了低糖无硫南瓜脯的最适加工工艺。结果表明:非硫护色剂组合为NaCl1.5%,柠檬酸0.6%,抗坏血酸0.1%;提高南瓜脯饱满度的试剂及质量分数为明胶0.7%,羧甲基纤维素钠0.8%;糖液组成包括蔗糖、果葡糖浆、安赛蜜,其质量分数分别为35%、25%、0.02%,真空渗糖工艺参数为真空度0.09MPa,温度50℃,维持真空时间20min,破除真空时间20min,抽真空次数为3次。     

Bisulfite Atlernatives in Processing Abrasion-Peeled Russet Burbank Potatoes

Whole, abrasion-pecled Russet Burbank potatoes were dipped in a solution containing 3% D-araboascorbic acid (erythorbic acid), 0.25% sodium acid pyrophosphate and 2% sodium chloride or water. They were drained and packed in 0.2% citric acid, 0.2% sorbic acid and 0.25% calcium chloride or water, sealed in plastic bags and stored at 3.8°C. Potatoes packed in the citric acid mixtures maintained a lower microbial load after 6 days storage when compared to bisulfite-treated or water-dipped potatoes. All potatoes maintained acceptable color through 18 days storage. Treatments did not alter shear force measurements of raw, peeled potatoes or perceived flavor and texture of cooked, mashed potatoes.     

INFLUENCE OF CHEMICAL TREATMENT ON QUALITY OF CUT APPLE (cv. JONAGORED)

The quality of a new variety of apple, ‘Jonagored’, after peeling and cutting was evaluated during ten days of storage in air at 4C. The objective was to evaluate the shelf-life of apple cubes by detecting the limiting parameter and to test the influence of different chemical dips on the cut apple quality with the aim of extending shelf-life. Color, i.e. browning at the cut surface, was found to be the critical quality parameter determining the shelf-life of the cut apple to less than three days. There were no significant differences between the dip treatments in measurements of CIE values. When apple cubes were treated with ascorbic acid, ascorbic acid plus calcium chloride or ascorbic acid plus calcium chloride and citric acid, the 0.75% ascorbic acid dip was found to be the most effective preservation treatment in terms of reducing color change of the cut surface. Both 0.75% ascorbic acid and 0.75% ascorbic acid plus 0.75% calcium chloride inhibited the loss of firmness of apple cubes. When citric acid was added to the dip treatment, there were color changes similar to those of the control.     

Effect of Pretreatments and Air‐Frying,a Novel Technology,on Acrylamide Generation in Fried Potatoes

This paper investigated the effect of air‐frying technology, in combination with a pretreatment based of soaking the samples in different chemical agent solutions (citric acid, glycine, calcium lactate, sodium chloride, or nicotinic acid [vitamin B3]), on the generation of acrylamide in fried potatoes. The influence of reducing sugars on the development of surface's color was also analyzed. The experiments were conducted at 180 °C by means of air‐frying and deep‐oil‐frying, as a reference technology. Based on the evolution of color crust with frying time, it could be concluded that the rate of Maillard reaction decreased as the initial reducing sugars content increased in the raw material, and was also lower for deep‐oil‐frying than for air‐frying regardless of pretreatments applied. Air‐frying reduced acrylamide content by about 90% compared with conventional deep‐oil‐frying without being necessary the application of a pretreatment. However, deep‐oil fried potatoes pretreated with solutions of nicotinic acid, citric acid, glycine at 1%, and NaCl at 2% presented much lower acrylamide levels (up to 80% to 90% reduction) than nonpretreated samples.     

即食香菇方便食品生产工艺研究

本实验通过L9(34)正交试验对即食香菇方便食品加工工艺的硬化和护色操作进行了系统研究,用0.1%氯化钙和1.0%氯化钠混合溶液硬化处理25min为硬化工艺的最佳条件;而护色工艺的最佳条件则为0.3%柠檬酸和0.05%抗坏血酸混合溶液烫漂处理5min。并采用梯度升温干燥工艺,开发出具有浓郁川味特色的香菇休闲食品。     

Effect of preservative agents on the respiration rate of minimally processed potato (Solanum tuberosum cv. Monalisa)

ABSTRACT:  The shelf life of minimally processed potatoes (MPP) is limited by enzyme-catalyzed browning reactions, with the increase in respiration being another factor that affects quality retention of this product. Sulfites are commonly used as effective preservative agents in minimally processing potatoes, but ascorbic acid and citric acid are considered natural sulfite substitutes and more accepted by consumers. The aim of this study was to study the effect of combinations of the preservative agents cited above (sodium metabisulfite 0.1% and 0.5%; citric acid 0.1% and 0.5%; ascorbic acid 0.5%) on the respiration rate of MPP (cv. Monalisa) processed at both ambient and refrigerated temperatures. The results have revealed that there is a significant effect of dipping treatment and temperature on respiration rate of MPP. Sodium metabisulfite (SM) reduces respiratory activity up to 0.8 mL/kg/h. The addition of either citric or ascorbic acid enhanced the effect of SM on the reduction of the respiration rate of MPP. The strongest effect (up to 3.3 mL/kg/h) was observed when a combination of all 3 agents at the higher concentrations was employed at a temperature of 18 °C.     

POLYPHENOLOXIDASE ACTIVITY OF MINIMALLY PROCESSED 'JONAGORED' APPLES (MALUS DOMESTICA)

The influence of three chemical dips using ascorbic acid (AA), citric acid (CA) and calcium chloride (CC) on the polyphenoloxidase (PPO) activity and on the total phenolic content of minimally processed (MP) apple (Malus domestica, cv. Jonagored) during cold storage was evaluated and a potential relationship with enzymatic browning was investigated. An ascorbic acid dip (42.6 mM) of 5 min duration was the most efficient chemical treatment in reducing the PPO activity of apple cubes. A 92% inhibition was achieved after 7 days of storage at 4C. All treatments were advantageous in comparison to the control in reducing color changes. Color changes, determined by absorbance at 420 nm (soluble pigments) and lightness (L) (insoluble pigments) of apple cubes treated with ascorbic acid were correlated with total phenolic content. No correlation was observed between PPO activity and tristimulus color parameters, browning index or total phenolic content of AA‐treated apple cubes.