Carotenoid Pigments and Colour of Hermaphrodite and Female Papaya Fruits ( Carica papaya L) cv Sunrise During Post-Harvest Ripening

The predominant carotenoids in extracts of female and hermaphrodite Papaya fruits (Carica papaya L) Solo cv Sunrise were determined by high-performance liquid chromatography on a C₁₈ reversed-phase column using a diode-array detector. Three classes of carotenoids were separated and identified from the papaya extract without saponification; these were xanthophylls, hydrocarbon carotenoids and carotenol fatty acid esters. The xanthophylls were identified as trans-zeaxanthin, cryptoflavin and β-cryptoxanthin; other xanthophyls were detected in very small quantities. The major hydrocarbon carotenoid was identified as lycopene. Carotenol fatty acid esters were identified as carotenol fatty acid esters of β-cryptoxanthin, cryptoxanthin-5,6-epoxide, lutein, zeaxanthin and violaxanthin. There were no qualitative differences among the carotenoid pattern of female and hermaphrodite papaya fruits. Changes in carotenoid composition during ripening in hermaphrodite and female papaya fruits (cv Sunrise) were investigated in three different stages of ripeness. These changes could be shown in terms of Hunter colour values.     

Thermal Diffusivity of Papaya Fruit (Carica papaya L., Var. Solo)

The thermal diffusivity of papaya pulp is measured to be 1.52 × 10^-3 cm²/s and found to be in agreement with the value predicted by the Riedel equation within the uncertainty of the measurement. The thermal diffusivity of papaya seeds is measured to be 1.60 × 10^-3 cm²/s.     

Influence of Edible Coating on the Drying and Quality of Papaya (Carica papaya)

The edible coating applied to food pieces prior to hot air drying is a technology that can improve the nutritional and sensory qualities of dehydrated products. The effects of the pectin coating technique on the drying efficiency and quality of papaya slices of the Formosa cultivar were investigated, determining the cell structure, color, and vitamin C contents of the fresh and dried fruits, with and without a pectin coating. The drying kinetics was evaluated based on Fick’s Law. The analytical solution for a plane sheet was used to estimate the water effective diffusion coefficients, and, in order to take into account shrinkage during drying, the average and variable thicknesses were considered in an approximate manner. Diffusion modeling presented a better fit when considering the thickness of the slices as variable. Regarding fruit quality, the coating applied to papaya slices before drying enhances vitamin C retention in comparison to papaya dried without coating, showing that pectin coating efficiently prevented oxidation of this bioactive compound. In addition, the moisture diffusivity of the coated samples was higher than that of the non-coated slices, due to the hydrophilic nature of the pectin. Light and transmission electron microscopy images revealed intense rupturing of the cell membranes in the dried tissues. The cell tissue arrangement in the coated papaya slices was similar to that found in the fresh papaya slices, before and after drying.     

Chemical composition of papaya (Carica papaya) seeds

Defatted and undefatted seeds of papaya (Carica papaya) were analyzed for proximate composition, some toxicants, sugar composition, mineral content, physico-chemical properties of the seed oil and the fatty acid spectrum of the seed oil. The seed is a rich source of proteins (27·8% undefatted, 44·4% defatted), lipids (28·3% undefatted) and crude fibre (22·6% undefatted, 31·8% defatted). Of the toxicants estimated, glucosinolates occur in the highest proportion. The seed is low in free monosaccharides. Sucrose is the predominant sugar (75·0% of total sugars). Mineral content is generally low. However, Ca and P occur in appreciable quantities (17 340 μg/g and 10 250 μ/g, respectively). The seed oil is low in iodine value (74·8), free fatty acids (0·94%) and carotene (0·02 μg/g). The major fatty acid is C18:1 (79·1%).     

Stability of carotenoids in freeze dried papaya (Carica papaya)

Effect of water activity ( a _w) and storage temperature on the degradation of carotenoids in relation to keeping quality of freeze dried papaya is reported. Carotenoids were found to be most stable at 0.33 a _w and both below and above this level their rate of destruction was higher. Above 0.40 a _w browning limited the storage life. Freeze dried papaya has maximum stability between 0.22-0.33 a _w.     

Solar drying characteristics of papaya (Carica papaya) latex

Dripped, congealed and a mixture of dripped and congealed papaya latexes of varying charge sizes were dried in a rock-bed solar dryer over a temperature range of 40–60°C. The time taken for the fresh latex to dry from an initial moisture content of between 73 and 80% (wet basis) to an equilibrium moisture content of between 6 and 8% varied from about 1·5 to 36 h depending upon the charge size. The latex, whether dripped or congealed, dried as pale yellow flakes which could easily be powdered and had a proteolytic activity slightly higher than that of the fresh latex.     

Organic Acid Changes During Ripening of Processing Peaches

Organic acids and their changes during peach (Prunus persica L. Batsch) fruit ripening were quantified by HPLC for clingstone culti-vars,‘Babygold 5’and‘Babygold 7′, and a freestone cultivar,‘Cresthaven’. At full maturity,‘Babygold 5’and‘Babygold 7’had about 60% malic, 20% citric and 19% quinic acid; whereas‘Cresthaven’had similar amounts of all three organic acids (37, 3.5 and 28%, respectively). During fruit ripening,‘Babygold 5’and‘Babygold 7’increased in malic acid and decreased in citric and quinic acids, whereas,‘Cresthaven’showed little change in these organic acids.     

Pectinesterase and Polygalacturonase Activities and Textural Properties of Rubbery Papaya (Carica papaya Linn.)

: Comparisons in color of flesh, pectin composition, pectinesterase (PE), polygalacturonase, cellulase activities, and textural properties of normal green papaya (NGP), rubbery papaya (RP), and normal yellow and ripe papaya (NYRP) were conducted. RP contained about 9.7% pectin with a degree of esterification of 53.1%, while NYRP contained about only 1.2% pectin with a degree of esterification of about 23.4%. PE activity (13.6 unit/g fresh weight) than in RP was significantly lower (18.0 unit/g fresh weight) in NYRP (P < 0.05), whereas polygalacturonase activity (46.9 unit/g fresh weight) in RP was higher (27.0 unit/g FW) than in NYRP. Therefore, in combination with the fact that water extract from RP displayed an inhibitory ratio of 36.0% on papaya PE activity, we suggest the presence of certain substances with strong PE inhibitory activity in RP.     

Mineral composition of the papaya (Carica papaya variety sunrise) from Tenerife island

In this study we have determined the contents of macroelements (Na, K, Ca, Mg and P) and microelements (Fe, Cu, Zn, Mn and B) in papaya samples (Carica papaya) obtained and consumed on the island of Tenerife, Canary Islands. The analysis shows the existence of significant differences in mineral content in the papaya samples. The papaya coming from MercaTenerife (wholesaler) presents higher K, P and Mn concentration levels than the papaya coming from the South Area of Tenerife. On the other hand, Na concentration levels are higher in the samples coming from the South Area of the island. There are differences between the mineral contents of this fruit shown in some food composition data tables and those analyzed in this work. The former are lower in Na, K, Ca and higher in Fe. In the same way, it is appreciated that the levels of Na concentration found in this work are greater than those found by other authors, and lower in Fe. When we compare the results obtained in this work and the recommended daily intakes or daily estimated demands of mineral elements proposed by different institutions or authors we realize that papaya is an important source of certain mineral elements, mainly K, Mg and B.     

金华火腿加工过程中肌肉肌内脂的水解变化研究

研究了金华火腿股二头肌 (bicepsfemoris)肌内脂肪在加工过程中不同时期的水解变化情况。肌内脂使用氯仿 甲醇溶液提取 ,采用固相萃取法将中性脂 (主要为甘油脂 )、游离脂肪酸和磷脂分离 ,用毛细管气相色谱分别分析甘油脂、游离脂肪酸和磷脂脂肪酸的种类与比例。通过比较不同时期样品的色谱结果 ,发现在金华火腿原料中磷脂脂肪酸的不饱和脂肪酸百分含量较高 ,尤其是多不饱和脂肪酸的含量高达 4 9 2 2 %。且在金华火腿成熟过程中 ,磷脂水解作用显著 ,而甘油脂脂肪酸百分比例比较稳定 ,说明甘油脂水解作用相对较弱。     

超声辅助酶法提取虾黄油脂及其脂肪酸组成分析

以克氏原鳌虾虾黄为原料,研究超声辅助酶法提取其油脂的工艺,并运用气相色谱（gas chromatography,GC）法分析其脂肪酸组成。虾黄油脂提取的优化条件为水料比3∶1 （ mL/g）、添加质量分数0.6%的复合蛋白酶、在52 ℃条件下、用150 W的超声波处理125 min,虾黄油脂的提取率可以达到77.86%。提取的虾黄油脂经GC分析,检测出从C14～C24共26 种脂肪酸,其中饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸占脂肪酸总量的相对含量分别为40.67%、31.47%和27.92%,ω-3和ω-6系列脂肪酸占脂肪酸总量的9.68%。     

Physicochemical Changes in Seven Tomato (Lycopersicon esculentum) Cultivars During Ripening

Seven tomato cultivars were studied for compositional changes during ripening at green, breaker, turner, and ripe stages. Result indicated changes in total soluble solids (4.15 to 6.62 g/100 g), acidity (0.36 to 0.54 g/100 g), reducing sugars (0.76 to 4.04 g/100 g), total sugars (1.67 to 5.52 g/100 g), lycopene in skin (0.07 to 14.28 mg/100 g), and in pulp (0.04 to 6.73 mg/100 g) during ripening from green to red ripe stage. Cultivar UC-828 was found superior with respect to total soluble solids (6.62 g/100 g), reducing sugars (4.04 g/100 g), and total sugars (5.52 g/100 g) where as cultivar 8–2–1–2–5 was found superior with respect to lycopene in skin (14.28 mg/100 g) and in pulp (6.73 mg/100 g). Hunter color values showed a change from negative value of ‘a’ (greenness) to positive values (redness) where as ‘b’ decreased. The (b/a) and tan^?1 (b/a) showed a similar pattern of first increased and then decreased. The puncture resistance was decreased from 10.5 to 2.3 N indicating softening during ripening. Correlation studies showed that lycopene content best correlated with Hunter ‘a’ values during ripening (R² = 0.84 to 0.93). Intercultivar variation in physicochemical parameters at all stages of ripening revealed that Castle Rock was the best cultivar.     

The component acids of Carica papaya (caricaceae) seed oil

By the application of reversed-phase partition column chromatography, the oil from the seeds of Carica papaya was found to contain the following acids: lauric, 0.4%; myristic, 0.4%; palmitic, 16.2%; stearic, 5.0%; arachidic, 0.9%; behenic, 1.6%; hexadecenoic, 0.8%; oleic, 74.3%; and linoleic, 0.4%.     

Carotenoids in yellow‐ and red‐fleshed papaya (Carica papaya L)

Vitamin A deficiency is a disorder of public health importance in Sri Lanka. A recent national survey revealed that 36% of preschool children in Sri Lanka have vitamin A deficiency (serum retinol <0.2 µg ml^?1). In view of its well‐established association with child morbidity and mortality, this is a reason for concern. One of the main fruits which has been recommended for prevention of vitamin A deficiency in Sri Lanka is papaya (Carica papaya L). In this study the carotenoid profiles of yellow‐ and red‐fleshed papaya were analysed by medium‐pressure liquid chromatography (MPLC) and UV‐vis spectrophotometry. A section of yellow‐fleshed papaya showed small carotenoid globules dispersed all over the cell, whereas in red‐fleshed papaya the carotenoids were accumulated in one large globule. The major carotenoids of yellow‐fleshed papaya were the provitamin A carotenoids β‐carotene (1.4 ± 0.4 µg g^?1 dry weight (DW)) and β‐cryptoxanthin (15.4 ± 3.3 µg g^?1 DW) and the non‐provitamin A carotenoid ζ‐carotene (15.1 ± 3.4 µg g^?1 DW), corresponding theoretically to 1516 ± 342 µg kg^?1 DW mean retinol equivalent (RE). Red‐fleshed papaya contained the provitamin A carotenoids β‐carotene (7.0 ± 0.7 µg g^?1 DW), β‐cryptoxanthin (16.9 ± 2.9 µg g^?1 DW) and β‐carotene‐5,6‐epoxide (2.9 ± 0.6 µg g^?1 DW), and the non‐provitamin A carotenoids lycopene (11.5 ± 1.8 µg g^?1 DW) and ζ‐carotene (9.9 ± 1.1 µg g^?1 DW), corresponding theoretically to 2815 ± 305 µg kg^?1 DW mean RE. Thus the carotenoid profile and organisation of carotenoids in the cell differ in the two varieties of papaya. This study demonstrates that carotenoids can be successfully separated, identified and quantified using the novel technique of MPLC. Copyright © 2003 Society of Chemical Industry     

Changes in Numbers and Kinds of Lactic Acid Bacteria During Ripening of Kefalotyri Cheese

Changes in lactic acid bacteria in ripening Kefalotyri cheese were studied. Throughout ripening lactobacilli and enterococci counts were high (lactobacilli 10⁶-10⁹/g, enterococci 10⁴-10⁷/g). Leuconostocs, lactic streptococci and betabacteria disappeared early in ripening. Leuconostoc lactis and Streptococcus thermophilus prevailed intitially (23% and 13%, respectively). Enterococcus faecium, Lactobacillus casei and L. plantarum became predominant with ripening. After 4 months ripening, E. faecium were dominant (35.5%) followed by L. plantarum (18.4%) and L. casei subsp. casei (15.8%). Results suggested that a starter consisting of both lactic acid bacteria that disappeared early and lactic acid bacteria that survived throughout ripening should be preferable for the production of Kefalotyri cheese.     

The storage and drying characteristics of papaya (Carica papaya L.) latex

A range of latex storage and air drying conditions were studied with regard to the proteolytic activity of the dried latex (‘crude papain’). The optimum drying temperature is between 50–55°C, activity losses on drying can be restricted to about 7% under these conditions. The activity of crude papain is the same if it is derived either from exuded latex or from that portion (about 20% of latex yield) which coagulates on the fruit surface on tapping. Latex storage at tropical ambient for 2–24 h prior to drying (with or without exposure to sunlight) causes maximum losses of about 20% in the proteolytic activity of the crude papain. Sodium chloride addition has an anti-coagulating effect on latex and accelerates the later stages of drying. Contrary to earlier reports, this causes a decreased activity in the product, which may be related to changes in latex pH. Addition of EDTA or sodium bisulphite, singly or in combination, protects the latex activity (increases of 20–25% relative to controls).