I mash the grapes, strain the juice, make sure it is blended and then look through the refractometer to measure brix or I put it in a hydrometer
There are many factors I take into consideration when determining when to harvest. I like to evaluate the grapevines, the grape clusters, the seeds and then evaluate the color, smell and taste of the grape juice. Then I have to take into account the weather before and during proposed harvest, labor available and set the date for harvest. Weekends are generally a better time to harvest because more volunteers can help. Next I need to make sure the winery side of everything is ready to process and ferment the grapes. In other words, when I am not running around the vineyard yelling at birds, I am inventorying the wine making materials, ordering yeast and looking at the maintenance of the pump, crusher and de-stemmer. It has been said a million times, “great wines are made in the vineyard”. If I don’t get this first part correct, then I may as well just go home! Nothing is more frustrating than working with substandard wines.
Last night I took a good look at the grapes in Three Texans vineyard. I collected grapes samples and processed them this afternoon. Looks like Tempranillo is still winning the ripeness race. In testing, I found them to have 22 degrees Brix and pH 3.65. Good color, a little light on taste, but definitely in the mellow plum direction. Starting to feel that bit of zing that tannins can add to the wine. Some grapes were still a bit harder, and some were soft and ripe. Same with the seeds, some beige and a few green. In the vineyard I saw some rachis and peduncle browning, but these grapes could definitely hang for another week or two. So harvesting on Saturday, August 9th would be a great idea, but looking at the long-range forecast, they are calling for an 80% chance of rain on Friday, August 8! So I think that these grapes should be harvested on Wednesday or Thursday August 6-7.
Next I examined the Malbec. These grapevines look a bit riper in the vineyard. The grapes have almost no green left in them. They were easy to pull off, soft, juicy and easy to mush. I thought maybe they had jumped ahead of the Tempranillo in ripeness, but when I looked at the sugar, I got 20.8 degrees Brix and pH 3.51. It still had a bit a of apple cider like tartness and had a few green seeds, so it needs a couple more weeks. I am predicting August 16 for these grapes.
Then the Cabernet Sauvignon from Three Texans. Cab seems to be the worst variety for uneven ripeness and had many green grapes still sprinkled about. I did see a bit of peduncle and rachis browning. For flavors I was tasting a very cherry or raspberry note which indicates that it needs more time. (see https://winegrapes.tamu.edu/grow/ripening.pdf for reference) I was surprised to see 20.4 degrees Brix, but the pH was only 3.26, so I would like to see these grapes hang 3 more weeks to ripeness. A good ripe Cabernet Sauvignon will make a better wine and fetch a higher price. If it is harvested too early, it might as well become Rootin’ Tootin’.
This morning I took a good look at my vineyard. First I sampled the Chardonnay. The grapes are starting to become translucent with a light golden hue. Starting to see brown peduncles and rachis. When I smashed the grapes, I had great brown seeds. So I was surprised to only measure 20.4 ° brix and pH 3.55. Given the state of the vines, the taste of the juice (starting to get mango) the darkness of the seeds, I will probably plan to harvest these grapes just before next week’s rain. In other words, I will harvest them on August 6-7.
The Merlot in my vineyard is starting to look ripe as well, but I have some problems with uneven ripening on the ends. I saw some peduncle browning and so I was disappointed to see how many green seeds I still had and to have only 18.7 °brix and pH 3.38. The taste was also a bit unripe. So this will probably wait until August 13-17, assuming that rain is going to fall on August 8th and that there isn’t much rain after that.
I couldn’t detect much difference between the aromas of the wine grapes, but there is quite a bit of difference in color and flavor of the juice.
Tempranillo, a few more green seeds than we want to see
chardonnay on the right–nice brown ripe seeds
Tempranillo, Malbec, Cabernet Sauvignon second row is Chardonnay then Merlot
Big differences in color, small variation in aromas