## 1 Introduction  
Orange (_Citrus cinensis_) juice is undoubtedly one of the most consumed products worldwide and this is mainly due to its nutritional value, as it is a source of vitamin C and other antioxidant compounds [1], but is also due to its distinguishing sensory characteristics, which can be attributed to the presence of a variety of aldehydes, esters, ketones, terpenes and alcohols. Plus, orange juice is the most widespread among fruit juices, representing almost 45% of the market worldwide [2].  
Due to its global distribution, the need has emerged for increasing shelf life of orange juice, because fresh squeezed orange juice was estimated to have a shelf life of ~7 days due to microbiological and physicochemical deterioration [3]. For that reason, thermal pasteurization of citrus juices, which mainly focuses on enzyme inactivation and deteriorative microflora, is the most applied technique globally [4]. Although with thermal pasteurization of citrus juices safety is guaranteed, there is a significant impact on the sensory characteristics of the end product and more specifically on color, odor and taste, so proper selection of time and temperature combination in thermal processing is important [5].  
Although it is very easy nowadays to evaluate with laboratory techniques how compromised is the microbiological quality of a product, evaluation of sensory deterioration is still challenging, but the correlation between microbiological and sensory quality, and more specifically safety and sensory shelf life, is extremely important [6; 7]. Accelerated shelf-life testing (ASLT) is a reliable tool for establishing a product's shelf life without the need for extensive time or tools, using temperature as an acceleration factor [8; 9; 10].  
When accelerated shelf-life tests are used, products are typically stored under a variety of temperatures, and at distinctive time periods, measures are taken in order to evaluate possible defects of the products. Different types of pasteurized fruit juices, including orange, were evaluated sensorially stored at different temperatures in order to specify the threshold where the defect appears and the nature of it [11; 12; 13; 14; 15; 16].  
Balanced incomplete block designs (BIBDs) are essentially innovative short-term sensory test techniques that include untrained assessors and provide reliable results. More specifically, BIBDs are recommended when a large number of samples under testing induce sensory fatigue, leading to compromised results. For the use of BIBDs, a number of prerequisites need to be met such as: (1) at each sensory session, the panelists only evaluate a fraction (k) of the total number of samples (t), (2) all samples are evaluated the same number of times (r), (3) the number of encounters of a similar pair of samples is the same for every other pair, defined as (\(\lambda\)), (4) the number of blocks (b) each including a different fraction of samples, which is also equivalent to the number of participants, needed to run an overall cycle of the experiment [17; 18; 19].  
So far, however, there has not been a large-scale sensory experiment using untrained consumers, which is the target group of the market, for the evaluation of the sensory shelf life of orange juice stored under different temperatures, and also the correlation between sensory and microbiological shelf life has not been investigated. Thus, the present study aims mainly to assess the consumer acceptance rate of pasteurized orange juice stored under different temperature levels and secondly to investigate whether rejections of orange juices based on sensory defects perceived by consumers appear within the microbiological safety limits. Due to the innovative character of the present work and the methodology used, literature regarding its content is scarce.