Harvest and use

Harvesting rhubarb |

When can I harvest? : Before harvesting your first harvest, you will have to wait. The year after planting, you will be able to harvest only a few stems. Usually, in the third year, the harvests will be more abundant. When the leaves are at their full length, you can take the stems. Harvest about 2/3 of the stems to allow the plant to regenerate. So you could even have a second harvest in the fall. On the other hand, the taste will possibly be more bitter.

Should we cut or pull out the stems? :
Rhubarb should be pulled out and not cut as this does not encourage the regrowth of new stems.

Here are two techniques that make it easier to remove the stems:

Either by gripping the base of the stem and pulling sharply sideways on the stem.
Always grip the base of the rod but this time we turn 1/4 turn while pulling on the rod.

Rhubarb harvest by Hélène Laurendeau

Harvesting rhubarb by Marthe Laverdière

Storing rhubarb |

Preservation in water: Once cut the stems can be preserved by filling a glass jar halfway with water and placing the rhubarb stems, base down, in the water . Cover with a plastic bag and refrigerate until ready to use. Rhubarb preserved in this way is intended to be used within a few days. If you don't have room to store the stalks upright, you can also keep the rhubarb stalks wrapped loosely in a plastic bag.

Preserving in aluminum foil: Arrange the rhubarb stalks on a large piece of aluminum foil. Wrap the foil around the rhubarb stalks loosely but snugly, gently squeezing the ends (you don't want it to be airtight) and place in the refrigerator until needed. Rhubarb should be kept like this for at least a month, sometimes more.

Store in the freezer: Rinse the rhubarb stalks with water and dry. Cut the washed rhubarb into 2cm pieces and arrange in a single layer on a baking sheet; freeze until solid, about 3 to 4 hours. Transfer the frozen rhubarb pieces to resealable plastic freezer bags and store in the freezer for up to a year, or up to three years if vacuum-packed.

Use of rhubarb in cooking |

It is the Anglo-Saxons who know best how to exploit its taste treasures: jam, chutney, compote, tart, soufflé, not to mention the savory version, with fatty meats to which it brings a welcome acidity. Rhubarb can be baked, pan-fried, simmered, poached or pureed. It can also be made into a very tangy juice, delicious in cocktails. Take a look at the flavor pairings with rhubarb.

rhubarb juice can very well replace lemon juice in recipes such as for making mayonnaise or vinaigrette or a cake . It is most often seen in jam, compote, pie or in rhubarb butter, but it can also be used in other types of desserts, and even in savory dishes, such as salads.

Culinary qualities of rhubarb: Color and juice of red cultivars |

Crop Diversification Center South analyzed eight cultivars for their culinary qualities. In terms of moisture content, all registered varieties have a moisture content between 92.2 and 94 percent. The pH, or measure of acidity, ranges from a low 4.87 for Cherry Red to a high of 3.94 for Valentine. Sucrose readings average nearly 5 percent across all varieties.

Juice content and red color intensity varied more. The following table lists the varieties with a red color from most intense to least intense and the corresponding juice yield.

Variety from most intense to least intense	Juice yield %
Valentine	76.6
Cherry Red	79.4
Early Sunrise	82.6
Cherry Wine	79.7
Mcdonald	77.7
Canada Red	79.7
German Wine	82.5
Strawberry	81.2

Source: Agdex, August 2002

Effect of different cooking methods on rhubarb polyphenols |

Polyphenolic compounds, such as anthraquinones and stilbenes, from Rheum species have been shown to exhibit diverse bioactivities relevant to human health. The article describes the polyphenolic composition of edible rhubarb (Rheum rhapontigen) petioles and the effects of common cooking methods on total polyphenol content, anthocyanin content, and total antioxidant capacity.

Most cooking methods (rapid simmering, slow simmering, and baking), with the exception of blanching, increased total polyphenol content and overall antioxidant capacity compared to the raw material. Variations in anthocyanin content and total polyphenol content between different cooking methods suggest a balance between two processes: cooking facilitates the release of rhubarb polyphenolic compounds but also induces their degradation.

In general, total polyphenol levels were higher in cooked rhubarb samples than in raw rhubarb samples. The highest concentrations were observed after slow cooking for 30 minutes, followed closely by cooked rhubarb at 20 minutes. Blanching appeared less effective, with polyphenol concentrations decreasing after 20 and 30 minutes, but it is likely that some components were lost as the blanching water was not retained. However, a decrease in total polyphenols was observed.

Liquid chromatography–mass spectrometry (LC–MS) analysis identified more than 40 polyphenolic compounds in raw rhubarb, including anthraquinone, stilbene, anthocyanin, and flavonol derivatives. Cooking had selective effects on the stability of the various polyphenolic compounds. Initially, the yield of all compounds increased, but the relative stability of the anthraquinone aglycones decreased significantly with increasing cooking time. Initial evidence of the turnover of other anthraquinone derivatives was obtained.

Source : Effect of different cooking methods on rhubarb polyphenols, Gordon J. McDougall, Pat Dobson, Nikki Jordan-Mahy, 2009
Rhubarb Juice as a Natural Antibrowning Agent |
Afin de rechercher des agents anti-brunissement naturels, le jus de rhubarbe a été testé sur des tranches de pommes fraîchement coupées et s'est avéré efficace. Des tranches de pommes Liberty ont été traitées avec différentes concentrations de jus de rhubarbe (5 % à 100 %), et le taux de décoloration à température ambiante a été mesuré à l'aide d'un colorimètre Hunter. Les tranches de pommes traitées avec la solution à 5 % à 10 % ont montré une activité brunissante avec des valeurs dL de 2,3 à 2,5 après deux heures. Cependant, les concentrations de jus de rhubarbe supérieures à 20 % ont inhibé efficacement le brunissement des pommes, sans modification de la valeur L pendant plusieurs heures.

La teneur en acide oxalique du jus de rhubarbe analysé dans cette étude était de 334 mg/100 g de jus. Sur la base de ce résultat, le jus à 10 % contenait environ 0,03 % d'acide oxalique et le jus à 20 % contenait 0,07 % d'acide oxalique. La valeur de 0,07 % d'acide oxalique dans le jus à 20 %, la concentration minimale approximative requise pour inhiber le brunissement, est proche de la concentration minimale de 0,05 % déterminée dans une étude précédente (Son et al. 1999). Par conséquent, l'activité anti-brunissement de la rhubarbe semble être principalement due à l'acide oxalique dans le jus de rhubarbe. L'activité anti-brunissement a également été testée après pasteurisation du jus de rhubarbe (pH 5 4,3) à 80 8C pendant 5 min. Le traitement thermique du jus de rhubarbe n'a pas affecté l'activité anti-brunissement sur les tranches de pomme (p , 0,05). De plus, le jus de rhubarbe a été traité au charbon actif pour obtenir un liquide incolore et inodore. Cette solution limpide s'est également révélée aussi active que le jus de rhubarbe non traité (p = 0,05). Nous concluons que le jus de rhubarbe est un agent anti-brunissement naturel très efficace pour les fruits et légumes frais coupés, et qu'il présente un fort potentiel commercial car il est facile à obtenir, peu coûteux, sûr, naturel et exempt de contraintes réglementaires.

Source : Rhubarb Juice as a Natural Antibrowning Agent, S.M. SON, K.D. MOON, AND C.Y. LEE, Journal Of Food Science, Vol. 65, No. 7, 2000
Rhubarb Measure Conversions |
2 to 4 stalks: 240 ml (1 cup) cooked rhubarb
1 pound of rhubarb = 3 cups chopped rhubarb
3 cups chopped rhubarb = 2 cups cooked rhubarb
15 medium stalks of rhubarb = 6 cups chopped rhubarb (approximately)
Note that these conversions have been rounded to standard measurements.
Looking for rhubarb recipes? |

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