Hi, Im a professional private chef. For several summers I worked in a lake house of a Jewish family whose members keep varying degrees of kosher. Within the house, they all seem respectful, eating only meat and pareve at those meals, only dairy and pareve at those meals, only pareve at those meals. The house has several ovens, sinks and stove tops, including ovens and sinks that are designated pareve - its a large house and kitchen. Whatever happens outside the kitchen and home isnt my business though Ill sometimes be told where someone ate or see the not kosher leftovers brought inside from the car to the garbage. No judgment. I had to say it because of my question. I have top quality knives and blenders I use. I was told the family members are afraid of the knives and blades and wouldnt use the knives and have no use for the blenders when Im at around. The blenders are of a horsepower in which any hard, raw food can be pulverized into a cream, a dressing, a soup, an ice cream or a drink. The blender technically "cooks" food as it quickly blends, unless its frozen for a smoothie or pareve ice cream so theres less heat. If its a little bit of whole apples, leafy greens and lemons to make a drink, theres a bit of "cooking. The food isnt necessarily hot, its never hot unless its a soup I already cooked and want to puree while its still warm or hot, or something similar, but its known that food that must keep its nutritional integrity can only be pulse blended in these blenders for a very small amount of time or put in with some frozen fruit or ice, if making a dressing or drink because it could otherwise heat up. Im not sure what temperature the food becomes and whether "cooking" here is applicable to the Jewish law of cooking. Ive only used pareve food with the knives and blenders so theres no concern about anything I did. Its all been pareve, used with pareve equipment and cleaned in the pareve sink. I left one of these blenders, with a label clearly marked pareve on the blender jar, in the home for a few weeks while I was away. Its on an easily accessible shelf. I also left the knives, marked pareve on each knife, on the first box theyre sealed in and on the box its stored in. Theyre in a safe, lower drawer, so they dont fall on anyone, with a childproof protection. Im back and as far as I know, no one touched the blender or the knives, though Im a little concerned because over time I learned that the family tends to be quick to give answers without asking around and will often reply with what they think I want to hear instead of making it easier by telling the truth. The concern is that they have guests who possibly used the items and not necessarily following Jewish law. The guests are known to enjoy cooking and dont follow or know the law. I was told that absolutely no one, from the family to the guests used any of my equipment and that Im the only one who uses it. Everything looks clean but they would have cleaned it. But again, they have a way with their answers about many issues throughout the years, not necessarily Jewish law, which has me concerned. The guests left last week. As I use these items to cook for people who keep kosher, in that family and others, Im asking for a little clarity about what to do because I would never want to use potentially not kosher equipment or not kosher equipment for any Jewish person. Thank you so much.

ב"ה Shalom I will answer you similarly to another question, I was recently asked. If the blender was possibly used for non-kosher use, it may be made fit again for Kosher use, by simply making the blender Kosher again. This is done by immersing the blender container and its blade into bubbling boiling water , after they have been thoroughly cleaned. Another simple solution to avoid any doubts is to just lock your equipment, keeping a key only with you when your are not present in the home. All the best